CN110081323B

CN110081323B - LED filament and LED bulb

Info

Publication number: CN110081323B
Application number: CN201910371440.0A
Authority: CN
Inventors: 江涛; 徐卫洪; 斎藤幸广; 鳗池勇人; 熊爱明; 徐俊锋
Original assignee: Jiaxing Super Lighting Electric Appliance Co Ltd
Current assignee: Jiaxing Super Lighting Electric Appliance Co Ltd
Priority date: 2018-05-23
Filing date: 2019-05-06
Publication date: 2021-08-31
Anticipated expiration: 2039-05-06
Also published as: CN110145698A; CN110145698B; CN110081323A

Abstract

An LED bulb lamp comprises a lamp shell; the lamp holder is connected with the lamp shell to form an accommodating space, and the lamp holder comprises a driving circuit; at least two conductive supports; the LED module comprises a light-emitting part and a light-emitting component, wherein the light-emitting part comprises a light conversion coating for coating a plurality of LED chip units, conductor sections and at least two electrodes which are respectively connected with the conductive support, each LED chip unit comprises at least two LED chips which are connected through a lead, and the LED chip units are electrically connected in the light-emitting part through the conductor sections; a portion of each of the electrodes is exposed outside of the light conversion coating; the electrode is connected with the LED chip unit through a first lead, and the conductor section is connected with the LED chip unit through a second lead; paste on LED filament base plate and have copper foil and LED chip, every LED chip reaches the first wire that is connected with the LED chip and second wire independently wraps up with first photoconversion layer, has increased heat radiating area, has promoted radiating effect and luminous efficiency.

Description

LED filament and LED bulb

Technical Field

The invention relates to the field of illumination, in particular to an LED filament and an LED bulb lamp using the same.

Background

Incandescent light bulbs have been widely used for decades for illumination in homes and businesses, however, incandescent light bulbs are generally less efficient in their energy usage, with approximately 90% of the energy input going to be dissipated as heat. And because incandescent bulbs have a very limited life (about 1,000 hours), they need to be replaced often. These conventional lamps are gradually replaced by other more efficient lamps, such as fluorescent lamps, high intensity discharge lamps, Light Emitting Diodes (LEDs), etc. Among these lamps, LED lamps are the most attractive lighting technology. The LED lamp has the advantages of long service life, small volume, environmental protection and the like, so the application of the LED lamp is continuously increased.

In recent years, an LED bulb lamp with an LED filament is available on the market. The LED bulb lamp using the LED filament as a luminous source in the market at present still has the following problems to be improved:

first, an LED hard filament is used having a substrate (e.g., a glass substrate) and a plurality of LED chips on the substrate. However, the lighting effect of the LED bulb lamp can be better only by combining a plurality of hard filaments, and the lighting effect of a single hard filament cannot meet the general demand in the market. Traditional ball bubble lamps and lanterns have the tungsten filament, can produce even light-emitting because the nature of the nature bendable of tungsten filament, however the effect of this kind of even light is difficult to reach to the hard filament of LED. There are many reasons why it is difficult to achieve this effect for the LED filament, except for the foregoing inflexibility, one of them is that the substrate can block the light emitted by the LED, and the light generated by the LED is a point light source, which can lead to light concentration. In contrast, a uniform light distribution results in a uniform illumination effect, while a concentrated light distribution results in an uneven and concentrated illumination effect.

In addition, there is also a soft filament of LED, which is similar to the above filament structure, and the glass substrate is partially replaced by a flexible substrate (hereinafter referred to as FPC), so that the filament can have a certain degree of bending. However, the soft filament made of the FPC has a thermal expansion coefficient different from that of the silica gel coating the filament, and the displacement and even the degumming of the LED chip are caused by long-term use; or the FPC is not favorable for flexible change of the process conditions and the like. In addition, the stability of the metal routing between the chips of the filament structure during bending is challenged, when the chips in the filament are arranged compactly, if the adjacent LED chips are connected in a metal routing mode, the stress is easily concentrated on the specific part of the filament due to the bending of the filament, so that the metal routing for connecting the LED chips is damaged or even broken,

in addition, the LED filament is generally disposed in the LED bulb, and in order to present an aesthetic feeling in appearance and to make an illumination effect of the LED filament more uniform and wide, the LED filament may be bent to present various curves. However, the LED filament has LED chips arranged therein, and the LED chips are relatively hard objects, so that the LED filament is difficult to bend into a desired shape. Further, the LED filament is also prone to cracking due to stress concentration during bending.

The existing LED bulb lamp is provided with a plurality of LED lamp filaments in order to increase aesthetic feeling in appearance and enable illumination effect to be more uniform, and the LED lamp filaments are set to be different placing angles. However, since a plurality of LED filaments need to be installed in a single LED bulb, and the LED filaments need to be individually fixed, the manufacturing process is more complicated, and the production cost is increased.

In addition, the driving requirement of the LED filament for lighting is substantially different from that of the traditional tungsten filament lamp. For an LED bulb, it is a design consideration how to design a power circuit to provide a stable current to make the ripple of the LED filament low enough when the LED filament is turned on, so that a user does not feel flickering. Secondly, due to the limitation of space, it is also a significant concern how to design a power circuit that is simple enough and can accommodate the space of the lamp holder on the premise of realizing the required lighting effect and the driving requirement.

Patent No. CN202252991U discloses that the upper and lower surfaces of a chip or the periphery thereof are coated with fluorescent powder respectively, the chip is fixed on a flexible PCB and is bonded and packaged by an insulating glue, the insulating glue is epoxy resin glue; the electrodes of the chip are connected with the circuit on the flexible PCB board through gold wires; the flexible PCB board is transparent or semitransparent, and the flexible PCB board is printed circuit preparation on polyimide or polyester film base plate and forms, adopts the flexible PCB board to replace aluminium base board support lamp radiating part, improves the heat dissipation. Patent publication No. CN105161608A discloses an LED filament light-emitting strip and a manufacturing method thereof, in which non-overlapping chip light-emitting surfaces are arranged in a face-to-face manner, so as to improve light-emitting uniformity and heat dissipation. Patent publication No. CN103939758A discloses that a transparent and heat-conducting heat dissipation layer is formed between the bearing surface of the carrier and the bonding surface of the LED chip for heat exchange with the LED chip. The aforesaid patent adopts PCB board, adjustment chip to arrange or form the heat dissipation layer respectively, though can improve the filament heat dissipation to a certain extent, nevertheless because of the radiating efficiency is low, and the heat is easy to be gathered. Finally, patent publication No. CN204289439U discloses a full-circle light-emitting LED filament, which includes a substrate mixed with phosphor, electrodes disposed on the substrate, at least one LED chip mounted on the substrate, and a packaging adhesive covering the LED chip. Through the base plate that contains the silicone resin of phosphor powder formed, avoided glass or sapphire as the cost of base plate, use the filament of base plate preparation has avoided glass or sapphire to the influence of chip light-emitting, has realized 360 degrees light-emitting, and light-emitting homogeneity and light efficiency improve greatly. However, the substrate is formed of silicone resin, which has a disadvantage of poor heat resistance.

Disclosure of Invention

It is specifically noted that the present disclosure may actually encompass one or more inventive aspects that may or may not have been presently claimed, and that several of the inventive aspects that may be present herein may be collectively referred to as "the invention" during the course of writing the description to avoid obscuring the unnecessary distinction between such possible inventive aspects.

This summary describes many embodiments relating to the "invention". The term "present invention" is used herein to describe only some embodiments disclosed in the specification (whether or not in the claims), and not a complete description of all possible embodiments. Certain embodiments of various features or aspects described below as "the invention" may be combined in different ways to form an LED bulb or portion thereof.

According to one embodiment of the invention, the LED filament comprises LED chips, electrodes and a first light conversion layer, and is characterized by further comprising a PI film and a copper foil, wherein the copper foil and the LED chips are pasted on the upper surface of the PI film, and the copper foil is positioned between two adjacent LED chips; the electrodes are configured corresponding to the LED chips, and the LED chips are electrically connected with the copper foil and the LED chips and the electrodes through leads; the LED chip is provided with a p-junction surface and an n-junction surface, the conducting wires comprise first conducting wires connected with the p-junction surface of the LED chip and second conducting wires connected with the n-junction surface of the LED chip, the first light conversion layers cover the first conducting wires and the second conducting wires connected with the LED chip, and the number of the first light conversion layers is the same as that of the LED chips.

Optionally, the first light conversion layer covers two ends of the copper foil, the area and the average thickness of the two ends of the copper foil covered by the first light conversion layer are equal or unequal, and the first light conversion layer covers 30-40% of the area of the upper surface of the copper foil.

Optionally, the first light conversion layer covers the copper foil, the area and the average thickness of the two ends of the copper foil covered by the first light conversion layer are not equal to the area and the average thickness of the middle of the copper foil covered by the first light conversion layer, and the thickness of the middle of the copper foil covered by the first light conversion layer is 30-50 um.

Optionally, the electrodes are copper foils located at the head and tail ends of the filament and extending beyond the PI film.

Optionally, the lower surface of the PI film covers a second light conversion layer, the second light conversion layer has an inclined side surface or an inclined side surface with an arc shape, and the upper surface of the PI film corresponds to the lower surface thereof.

According to another embodiment of the invention, an LED filament is disclosed, which includes LED segments, conductor segments, at least two electrodes and a light conversion layer, wherein the conductor segments are located between two adjacent LED segments, the electrodes are disposed corresponding to the LED segments and electrically connected to the LED segments, the conductor segments are located between two adjacent LED segments, and the conductor segments are electrically connected to the LED segments through wires.

Optionally, the LED segment includes at least two LED chips, and the LED chips are electrically connected to each other through a wire.

Alternatively, the conductor segments may comprise a wavy concave structure, a wavy convex structure or a spiral structure.

Optionally, the LED filament may comprise an auxiliary strip, the auxiliary strip extending through the conductor section.

Optionally, the conductor in the conductor section has a wave-like structure.

Optionally, the LED segment and the conductor segment have different particles, respectively, or the light conversion layer of the LED segment and the conductor segment is made of different materials.

According to another embodiment of the present invention, a composition suitable for manufacturing a filament substrate or a light conversion layer is provided, which at least comprises a host material, a modifier and an additive. The main material is organic silicon modified polyimide, the modifier is a thermal curing agent, and the additive is microparticles added in the main material and can contain fluorescent powder, heat dissipation particles and a coupling agent.

According to another embodiment of the present invention, the present invention provides a composition suitable for manufacturing a filament substrate or a light conversion layer, wherein the main material of the composition is an organosilicon modified polyimide which is a siloxane-containing polyimide, wherein the organosilicon modified polyimide comprises a repeating unit represented by the general formula (i):

optionally, in the general formula (I), Ar¹Is a 4-valent organic group having a benzene ring or alicyclic hydrocarbon structure, Ar²Is a 2-valent organic group, R is independently selected from methyl or phenyl, and n is 1-5.

Optionally, wherein Ar is¹Is a 4-valent organic group having a monocyclic alicyclic hydrocarbon structure or an alicyclic hydrocarbon structure containing a bridged ring.

Alternatively, according to another embodiment of the present invention, wherein Ar is Ar²Is a 2-valent organic group having a monocyclic alicyclic hydrocarbon structure.

Due to the adoption of the technical scheme, the invention can at least achieve one of the following beneficial effects or any combination thereof: (1) the copper foil and the LED chips are adhered on the LED filament substrate, and each LED chip and the first lead and the second lead which are connected with the LED chip are independently wrapped by the first light conversion layer, so that the heat radiation area is increased, and the heat radiation effect and the light emitting efficiency are improved; (2) the filament can be bent and lightened, the falling probability of the lead is reduced, and the reliability of the product is improved; (3) the LED filament structure is divided into the LED section and the conductor section, so that stress is easily concentrated on the conductor section when the LED filament is bent, and the probability of breakage of gold wires connected with adjacent chips in the LED section is reduced when the gold wires are bent, so that the overall quality of the LED filament is improved; in addition, the conductor section adopts a copper foil structure, so that the metal routing length is reduced, and the probability of metal routing fracture of the conductor section is further reduced; (6) the organic silicon modified polyimide resin composition prepared by adding a thermal curing agent into organic silicon modified polyimide serving as a main body has excellent heat resistance, mechanical strength and light transmittance; the organic silicon modified polyimide resin composition is used as the filament substrate, and the filament has good flexibility, so that the filament presents various shapes, and 360-degree full-circumference illumination is realized; (7) the LED bulb lamp comprises a single LED filament, and the LED filament has a symmetrical characteristic, so that the symmetrical characteristic is beneficial to generating uniform and wide light distribution, and the LED bulb lamp can generate the effect of full-cycle light; and (9) the power supply circuit can provide stable current to ensure that the ripple of the LED filament is low enough when the LED filament is lighted, so that a user does not feel flickering.

Drawings

Fig. 1A and 1B are schematic diagrams illustrating an LED bulb according to an embodiment of the invention;

FIGS. 2A to 2E are schematic perspective partial cross-sectional views of an LED filament according to an embodiment of the present invention;

FIGS. 3A to 3E are schematic structural views of various embodiments of the segmented LED filament of the present invention;

FIG. 4 is a graph showing a distribution of sizes of heat dissipating particles of different specifications;

FIG. 5A is a SEM image of a composite film of the silicone modified polyimide resin composition of the present invention;

FIGS. 5B and 5C are schematic cross-sectional views showing examples of composite films of silicone-modified polyimide resin compositions according to the present invention;

fig. 6A is a schematic diagram of another LED bulb using the LED filament of the present invention;

FIG. 6B shows a front view of the LED bulb of FIG. 6A;

FIG. 6C shows a top view of the LED bulb of FIG. 6A;

FIG. 6D is the LED filament of FIG. 6B as it would appear in a two-dimensional coordinate system defined with four quadrants;

FIG. 6E is the LED filament of FIG. 6C as it would appear in a two-dimensional coordinate system defined by four quadrants;

fig. 7A to 7C are schematic diagrams of LED filament circuits according to an embodiment of the invention;

Detailed Description

The present disclosure provides a new LED filament and an LED bulb using the same, which will be described in the following embodiments with reference to the accompanying drawings. The following description of various embodiments of the present invention has been presented for the purposes of illustration and example only and is not intended to be exhaustive or limited to the precise forms disclosed.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a" and "an" are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed terms and may be abbreviated as "/".

Terms such as "about" or "approximately" may reflect dimensions, orientations, or arrangements that vary only in a relatively minor manner and/or in a manner that does not significantly alter the operation, function, or structure of certain components. For example, a range from "about 0.1 to about 1" may encompass, for example, a range of 0% -5% deviation about 0.1 and 0% to 5% deviation about 1, particularly if such deviations maintain the same effect as the listed range.

Referring to fig. 1A and 1B, fig. 1A and 1B are schematic structural diagrams of a first embodiment and a second embodiment of the present invention. As can be seen from the figure, the LED bulb lamps 1a and 1b include a lamp housing 12, a lamp cap 16 connected to the lamp housing 12, at least two

conductive brackets

51a and 51b disposed in the lamp housing 12, a driving circuit 518 disposed in the lamp cap and electrically connecting the

conductive brackets

51a and 51b and the lamp cap 16, and a single light emitting portion 100 disposed in the lamp housing 12, where the light emitting portion 100 may be an LED filament including an LED chip.

The conductive supports 51a and 51b are used to electrically connect the two electrodes 506 of the light-emitting portion 100, and also to support the weight of the light-emitting portion 100. The driving circuit 518 is electrically connected to the

conductive brackets

51a and 51b and the lamp head 16, when the lamp head 16 is connected to a lamp socket of a conventional bulb lamp, the lamp socket provides power to the lamp head 16, and the driving circuit 518 is used for driving the light-emitting portion 100 to emit light after receiving power from the lamp head 16. Due to the symmetrical characteristics of the light emitting parts 100 of the LED bulb lamps 1a and 1b in terms of structure, shape, contour, curve, or the like, or the symmetrical characteristics of the light emitting parts 100 in the light emitting direction (the direction in which the light emitting surface of the LED filament faces in the present invention) (described in detail later), the LED bulb lamps 1a and 1b can generate all-round light. In the present embodiment, the driving circuit 518 is disposed inside the LED bulb. However, in some embodiments, the driver circuit 518 is disposed external to the LED bulb.

In the embodiment of fig. 1A, two conductive brackets 51A and 51b of the LED bulb lamp 1A are taken as an example, but not limited thereto, and the number of the conductive brackets is increased according to the conductive or supporting requirement of the light emitting part 100.

In the embodiment shown in fig. 1A and 1B, the LED bulbs 1A and 1B further include a stem 19 and a heat dissipation assembly 17, the stem 19 is disposed in the lamp housing 12, and the heat dissipation assembly 17 is located between the lamp cap 16 and the lamp housing 12 and is connected to the stem 19. In this embodiment, the base 16 is indirectly connected to the lamp housing 12 through the heat dissipation assembly 17. In other embodiments, the base 16 may be directly attached to the lamp envelope 12 without the heat sink assembly 17. The light emitting section 100 is connected to the stem 19 via the

conductive brackets

51a, 51 b. The stem 19 can be used for replacing air in the LED bulb lamp 1b with a mixture of nitrogen and helium. The stem 19 can also provide a heat conducting function, which conducts heat from the light emitting part 100 connected to the stem 19 to the outside of the lamp envelope 12. The heat sink 17 may be a hollow cylinder surrounding the opening of the lamp housing 12, and connects the stem 19 and the base 16 to conduct heat therefrom to the outside of the LED bulb 1 b. The driving circuit 518 may be installed inside the heat sink 17, and the outside of the heat sink 17 may be in contact with the external air to conduct heat. The material of the heat dissipation assembly 17 can be selected from metal, ceramic or high thermal conductivity plastic with good thermal conductivity. The heat dissipation assembly 17 (together with the opening/screw of the LED bulb) may also be made of a ceramic material with a good heat conduction effect, and the heat dissipation assembly 17 may also be an integrally formed assembly with the ceramic stem 19, so that the heat resistance of the heat dissipation path of the light emitting part 100 due to the fact that the lamp cap of the LED bulb needs to be glued with the heat dissipation assembly 17 can be avoided, and a better heat dissipation effect is achieved.

The

LED chip units

102 and 104, or referred to as

LED segments

102 and 104, may be a single LED chip, or two LED chips, or may include a plurality of LED chips, i.e., equal to or greater than three LED chips.

Fig. 2A to 2E are schematic perspective partial cross-sectional views of an LED filament according to an embodiment of the invention. As shown in fig. 2A, the

LED chip units

102 and 104,

electrodes

110 and 112, and wires are included. Unlike the previous embodiment, the light conversion coating of the present embodiment is divided into a first light conversion layer 121 and a base layer 122, the upper surface of the base layer 122 is attached with a plurality of copper foils 116 and

LED chip units

102 and 104, and the copper foils 116 are located between two adjacent

LED chip units

102 and 104; the

electrodes

110 and 112 are configured corresponding to the

LED chip units

102 and 104, and the

LED chip units

102 and 104 are electrically connected to the copper foil 116, and the

LED chip units

102 and 104 are electrically connected to the

electrodes

110 and 112 through wires; each of the LED chips in the

LED chip units

102, 104 has a p-junction and an n-junction, the wires include first wires 141 connecting the

electrodes

110, 112 and the LED chip units and second wires 142 connecting the copper foil 116 and the LED chip units, the first light conversion layer 121 covers the first wires 141 and the second wires 142 connecting the individual LED chip units and the LED chip units, and the number of the first light conversion layers 121 is the same as the number of the LED chip units. By adopting the design, the heat radiation area is increased, and the heat radiation effect and the light emitting efficiency are improved; the filament can be bent and lightened, the probability of wire falling or wire breakage is reduced, and the reliability of the product is improved.

According to the present embodiment, the single

LED chip units

102 and 104 may include two LED chips, or may include a plurality of LED chips, i.e., equal to or greater than three LED chips. The shape of the LED chip may be, but is not limited to, a long strip shape, and the long strip shape may have fewer electrodes, so as to reduce the chance of shielding light emitted from the LED chip. The

electrodes

110, 112 are disposed at two ends of the

LED chip units

102, 104 after being connected in series, a portion of each

electrode

110, 112 is exposed outside the first light conversion layer 121, each surface of the six faces of the LED chip in the

LED chip units

102, 104 is covered with the first light conversion layer 121, that is, the six faces of the

LED chip units

102, 104 are covered by the first light conversion layer 121, and the covering or wrapping may be, but is not limited to, direct contact, and preferably, in this embodiment, each surface of the six faces of the LED chip in the

LED chip units

102, 104 is directly contacted with the first light conversion layer 121. However, in practice, the first light conversion layer 121 may cover only at least one of the six surfaces of the LED chip of each

LED chip unit

102, 104, i.e. the first light conversion layer 121 directly contacts the surface, which may be the top surface. Also, the first light conversion layer 121 may directly contact at least one surface of the two

electrodes

110, 112 or the copper foil 116.

The lead is gold wire or aluminum wire, and the combination of the copper foil 116 and the gold wire brings a stable and flexible conductive structure for the filament. The copper foil 116 may be replaced by other materials with good conductivity, and the width or/and length of the opening of the copper foil 116 is larger than the

LED chip units

102 and 104 to define the positions of the

LED chip units

102 and 104, and at least two or more surfaces of the six surfaces of the

LED chip units

102 and 104 are in contact with each other and are covered by the first light conversion layer 121. The plurality of

LED chip units

102, 104 are connected to the copper foil 116 through wires to form a series circuit, a parallel circuit, a series circuit and then a series circuit, or a parallel circuit and then a parallel circuit, and then the

LED chip units

102, 104 at the front end and the rear end of the circuit are respectively connected to two

electrodes

110, 112 fixed on the base layer 122, and the

electrodes

110, 112 can be connected to a power supply to provide the power supply for lighting the

LED chip units

102, 104.

The first light conversion layer 121 covers both ends of the copper foil 116, the area and average thickness of both ends of the copper foil 116 covered by the first light conversion layer 121 are equal or unequal, and the area of the upper surface of the copper foil 116 covered by the first light conversion layer 121 is 30-40%. In an embodiment, as shown in fig. 2B, two adjacent first light conversion layers may cover the entire copper foil 116 located between the two adjacent first light conversion layers, the area and the average thickness of the two ends of the copper foil 116 covered by the first light conversion layers 121 are not equal to the area and the average thickness of the middle of the copper foil 116 covered by the first light conversion layers 121, and the thickness of the middle of the copper foil 116 covered by the first light conversion layers 121 is 30-50 um. The surface of the first light conversion layer 121 is arc-shaped, the height of the arc is gradually reduced from the middle to the two sides, and the included angle between the two sides of the arc and the base layer 122 is an acute angle or an obtuse angle.

The first light conversion layer 121 includes a phosphor paste or a phosphor film, at least a portion of each of the six surfaces of the

LED chip units

102 and 104 directly contacts the first light conversion layer 121 and/or one or both surfaces of the

LED chip units

102 and 104 are bonded to the first light conversion layer 121 through a die bond paste, which is also equivalent to the concept that the six surfaces are covered by the first light conversion layer 121 and/or the

LED chip units

102 and 104 directly contact the first light conversion layer 121.

As shown in fig. 2C, the difference from the above embodiment is that the lower surface of the base layer 122 is covered with the second light conversion layer 123 having a uniform thickness, and the upper surface and the lower surface of the base layer 122 are opposite to each other. As shown in fig. 2D, the second light conversion layer 123 covering the lower surface of the base layer 122 has an inclined side or an inclined side with an arc shape. The second light conversion layer 123 covers the lower surface of the base layer 122, so that more yellow fluorescence can be generated to reduce blue light, and thus the color temperature difference of light emitted from the front and back surfaces of the

LED chip units

102 and 104 can be reduced, and the color temperature of light emitted from both surfaces of the

LED chip units

102 and 104 can be closer.

In an embodiment, as shown in fig. 2E, the first light-converting layer 121 covers two adjacent

LED chip units

102 and 104, the copper foil 116 located between the two

LED chip units

102 and 104, and the first and

second wires

141 and 142 connected to the two

LED chip units

102 and 104. In one embodiment, the copper foil 116 has a silver coating 118 on its top surface, and the copper foil 116, which is located at the ends of the filament and extends beyond the base layer 122, serves as the

electrodes

110, 112. The silver coating 118 not only provides good conductivity, but also has the effect of increasing light reflection; a solder mask layer (not shown) is selectively arranged on the surface of the silver-plated layer, the thickness of the solder mask layer is 30-50 um, the solder mask layer is obtained by using an OSP (organic solder resist precursors) process, and the solder mask layer has oxidation resistance, thermal shock resistance and moisture resistance.

Referring to fig. 3A to 3E, fig. 3A to 3E are schematic diagrams of various embodiments of a segmented LED filament, and fig. 3A to 3C and fig. 3D to 3E are cross-sectional views of the LED filament along an axial direction thereof. As shown in fig. 3A to 3E, the LED filament can be divided into different segments in the axial direction of the LED filament, for example, the LED filament can be divided into LED segments (i.e. the LED chip units in the foregoing embodiments) 102 and 104 and a conductor segment 130, but not limited thereto. The number of the

LED segments

102, 104 and the conductor segments 130 in a single LED filament may be one or more, respectively, and the

LED segments

102, 104 and the conductor segments 130 are arranged along the axial direction of the LED filament. The

LED segments

102 and 104 and the conductor segment 130 can have different structural features to achieve different effects, as described in detail later.

As shown in fig. 3A, the LED filament 100 includes

LED segments

102 and 104, a conductor segment 130, at least two

electrodes

110 and 112, and a light conversion layer 120, wherein the conductor segment 130 is located between two

adjacent LED segments

102 and 104, the

electrodes

110 and 112 are disposed corresponding to the

LED segments

102 and 104 and electrically connected to the

LED segments

102 and 104, the two

adjacent LED segments

102 and 104 are electrically connected to each other through the conductor segment 130, in this embodiment, the conductor segment 130 includes a conductor 130a connecting the

LED segments

102 and 104, a length of the conducting wire 140 is smaller than a length of the conductor 130a, or a shortest distance between two LED chips respectively located in the two

adjacent LED segments

102 and 104 is larger than a distance between two adjacent LED chips in the single LED segment 102/104. In addition, in other preferred embodiments of the present invention, each

LED segment

102, 104 includes at least two LED chips 142, the LED chips 142 are electrically connected to each other, and the electrical connection is performed through a wire 140; the invention is not limited thereto. The conductor 130a in the conductor segment 130 is not in the form of a wire, but in the form of a sheet or film. In some embodiments, the conductor 130a may be a copper foil, a gold foil, or other material that can be electrically conductive.

The light-converting layer 120 covers the

LED segments

102 and 104, the conductor segment 130, and the

electrodes

110 and 112, and exposes a portion of each of the two

electrodes

110 and 112. In this embodiment, each of the six faces of the LED chips 142 in the

LED segments

102, 104 is covered by the light conversion layer 120, that is, the six faces are covered by the light conversion layer 120 and can be referred to as the light conversion layer 120 enveloping the LED chips 142, and this covering or enveloping can be, but is not limited to, direct contact, and preferably, in this embodiment, each of the six faces of the LED chips 142 is in direct contact with the light conversion layer 120. In various embodiments, the light conversion layer 120 may be an encapsulant without light conversion function, for example, the light conversion layer 120 of the conductor segment 130 may be a transparent encapsulant with good flexibility.

In some embodiments, the LED filaments 100 are disposed in the LED bulbs, and each LED bulb has only a single LED filament to provide sufficient illumination. Moreover, in order to present aesthetic feeling in appearance, the illumination effect of a single LED filament can be more uniform and wide, and even the effect of full-circle light is achieved, so that the LED filament in the LED bulb lamp can present diversified curves through bending and flexing, the light emitting direction of the LED filament faces all directions through the diversified curves, or the overall light emitting shape of the LED bulb lamp is adjusted by the diversified curves. In order to make it easier for the LED filament to be bent into such a curved structure, and the LED filament can also bear the bending stress, the conductor section 130 of the LED filament does not have any LED chip therein, but only has the conductor 130 a. The conductor 130a (e.g. a metal wire or a metal coating) is easier to bend with respect to the LED chip, i.e. the conductor segment 130 without any LED chip will be correspondingly easier to bend with respect to the

LED segments

102, 104 with LED chips.

As shown in fig. 3B, in the present embodiment, both the

LED segments

102, 104 and the conductor segment 130 of the LED filament 100 have different structural features. In the present embodiment, the conductor segment 130 further includes a wavy concave structure 132a, and the wavy concave structure 132a is disposed on the surface edge of the conductor segment 130 and surrounds the conductor segment 130 with the axial direction of the LED filament 100 as the center. In the present embodiment, the recessed structure 132a is recessed from the surface of the conductor segment 130. The plurality of concave structures 132a are arranged at intervals along the axial direction, and are parallel to each other, and present a continuous wave shape.

When the LED filament is bent, the conductor segment 130 can be used as a main bent part, and the conductor segment 130 is easy to extend and compress due to the wavy concave structure 132a of the conductor segment 130, and is more beneficial to being bent. For example, the conductor segment 130 extends outside and compresses inside the bend, and the wavy concave structure 132a improves the extension and compression. The extended recessed structure 132a becomes looser and smoother, i.e., the height drop becomes smaller and the distance between adjacent peaks or valleys becomes larger; the compressed recessed structure 132a becomes tighter and more recessed, i.e., the height drop becomes larger and the pitch between adjacent peaks or valleys becomes smaller. The conductor segment 130 is more easily bent due to the wave-like recess 132a providing a margin of extension and compression.

As shown in fig. 3C, in the present embodiment, both the

LED segments

102, 104 and the conductor segment 130 of the LED filament 100 have different structural features. In the present embodiment, the conductor segment 130 further includes a wavy protruding structure 132b, and the wavy protruding structure 132b is disposed on the surface edge of the conductor segment 130 and surrounds the conductor segment 130 with the axial direction of the LED filament as the center. In the present embodiment, the protruding structure 132b is a structure protruding from the surface of the conductor segment 130. The plurality of protruding structures 132b are arranged at intervals along the axial direction, and are parallel to each other, and present a continuous wave shape.

When the LED filament 100 is bent, the conductor segment 130 can be used as a main bending part, and the conductor segment 130 is easy to extend and compress due to the wavy convex structure 132b of the conductor segment 130, and is more beneficial to being bent. For example, the conductor segment 130 extends outside and compresses inside the bend, and the wave-like protrusion 132b compensates for the extension and compression. The extended raised structures 132b become looser and flatter, i.e., the height drop becomes smaller and the spacing between adjacent peaks or valleys becomes larger; the compressed protrusion 132b becomes tighter and more convex, i.e. the height difference becomes larger and the distance between adjacent peaks or valleys becomes smaller. The conductor segment 130 is more easily bent due to the wave-shaped protrusion 132b providing a margin for extension and compression.

As shown in fig. 3D, in the present embodiment, the light-converting layers 120 of the

LED segments

102, 104 and the light-converting layer 120 of the conductor segment 130 of the LED filament respectively include particles distributed therein. The

LED segments

102 and 104 and the conductor segment 130 may have different structures, different materials, different effects, or different distribution densities of particles, because the

LED segments

102 and 104 and the conductor segment 130 have different functions, and the light conversion layers 120 of the

LED segments

102 and 104 and the conductor segment 130 may have different types of particles to achieve different effects. For example, the light-converting layer 120 of the

LED segments

102, 104 can include phosphor 124a, while the conductor segment 130 light-converting layer 120 includes light-guiding particles 124 b. The phosphor 124a can absorb the light emitted from the LED chip 142 and convert the wavelength of the light to reduce or increase the color temperature, and the phosphor 124a also has the effect of light diffusion, so the phosphor 124a disposed on the light conversion layer 120 of the

LED segments

102 and 104 is helpful to change the color temperature of the light and also can make the light more uniformly dispersed. The conductor segment 130 has no LED chip, and the conductor segment 130 is used as a main bent portion of the LED filament, so the light guide particles 124b are disposed in the light conversion layer 120 of the conductor segment 130, and the light guide particles 124b have the effects of light diffusion and light conduction, which are helpful for conducting the light in the

adjacent LED segments

102 and 104 to the conductor segment 130, and further uniformly diffuse in the conductor segment 130.

The light guide particles 124b are, for example, but not limited to, particles made of polymethyl methacrylate (PMMA) or resin. In some embodiments, the particles included in the conductor segment 130 may also have excellent plastic deformation performance, such as particles made of plastic, which can improve the bending performance of the conductor segment 130 and enhance the support of the LED filament 100 during bending.

As shown in fig. 3E, in the present embodiment, the light conversion layer 120 of the

LED segments

102, 104 of the LED filament 100 includes light diffusing particles, such as the phosphor 124a, while the light conversion layer 120 of the conductor segment 130 does not include particles. In the present embodiment, the

LED segments

102 and 104 and the light conversion layer 120 of the conductor segment 130 are made of, for example, silicone, and no particles exist in the light conversion layer 120 of the conductor segment 130, so that the bendability of the conductor segment 130 can be improved.

In some embodiments, the material of the light-converting layer 120 of the conductor segment 130 and the material of the light-converting layer 120 of the

LED segment

102, 104 may be different. For example, the light-converting layers 120 of the

LED segments

102, 104 are made of silicon gel, and the light-converting layers 120 of the conductor segments 130 are made of a light-conducting material, such as PMMA, resin, or a combination thereof, but not limited thereto. Because the material of the light conversion layer 120 of the conductor segment 130 is different from the material of the light conversion layer 120 of the

LED segments

102 and 104, the conductor segment 130 and the

LED segments

102 and 104 can have different properties, for example, the conductor segment 130 and the

LED segments

102 and 104 can have different elastic coefficients, so that the

LED segments

102 and 104 have better support to protect the LED chip 142, and the conductor segment 130 has better flexibility, so that the LED filament 100 can be bent to present diversified curves.

In the present embodiment, each conductor segment 130 forms a smooth transition surface curve between the

adjacent LED segments

102 and 104, and the conductor segment 130 gradually tapers from one end of the

adjacent LED segments

102 and 104 toward the middle of the conductor segment 130, that is, the connection between the conductor segment 130 and the

LED segments

102 and 104 presents a smooth curve, so that when the LED filament is bent, the stress can be dispersed, and the stress will not concentrate between the conductor segment 130 and the

LED segments

102 and 104, thereby reducing the chance of cracks or even cracks in the light conversion layer 120. In other embodiments, the conductor segment 130 may be thicker than the

LED segments

102 and 104, and the light conversion layers 120 of the

LED segments

102 and 104 and the light conversion layers 120 of the conductor segment 130 may be made of different materials, for example, the light conversion layers 120 of the

LED segments

102 and 104 may be configured to be relatively rigid and have good support, and the light conversion layer 120 of the conductor segment 130 may be a flexible transparent package, for example, a package made of PMMA, resin, or other single material or composite material.

The embodiments shown in fig. 3A to 3E may be implemented individually or in combination. For example, the LED filament 100 shown in fig. 3B can be used in combination with the LED filament 100 shown in fig. 3D, that is, the conductor segment 130 of the LED filament 100 has the wavy concave structure 132a, and the particles distributed in the

LED segments

102 and 104 of the LED filament and the particles distributed in the conductor segment 130 have different sizes, different materials and/or different densities, so that the LED filament not only helps to be bent and bent, but also can make the light distribution more uniform, thereby enhancing the whole-cycle illumination effect.

The material content of the inventive LED filament with respect to the base layer is explained next. Materials suitable for manufacturing the flexible LED filament substrate or the light conversion layer must have characteristics such as excellent light transmittance, good heat resistance, excellent thermal conductivity, appropriate refractive index, excellent mechanical properties, and difficulty in warping. These properties can be satisfied by adjusting the kinds and content ratios of the main material, the modifier and the additive contained in the silicone-modified polyimide composition. The invention provides a filament substrate or a light conversion layer formed by a composition containing organic silicon modified polyimide, which can meet the characteristics, and can also adjust the characteristics of the filament substrate or the light conversion layer by adjusting the types and the contents of a main material, a modifier and an additive in a specific or partial composition so as to meet special requirements and environments. The adjustment of each characteristic is as follows.

Blending mode of organic silicon modified polyimide

The organic silicon modified polyimide provided by the invention comprises a repeating unit represented by the following general formula (I):

in the general formula (I), Ar¹Is a 4-valent organic group. The organic group may have a benzene ring or an alicyclic hydrocarbon structure, and the alicyclic hydrocarbon structure may be a monocyclic alicyclic hydrocarbon structure or an alicyclic hydrocarbon structure having a bridged ring. The organic group may be a benzene ring structure or an alicyclic hydrocarbon structure containing an active hydrogen functional group, and the active hydrogen functional group may be any one or more of a hydroxyl group, an amino group, a carboxyl group, an amide group, or a thiol group.

Ar²Is a 2-valent organic group, and the organic group can have an alicyclic hydrocarbon structure of a monocyclic system, or a 2-valent organic group containing an active hydrogen functional group, wherein the active hydrogen functional group is any one or more of a hydroxyl group, an amino group, a carboxyl group, an amide group or a thiol group.

Each R is independently selected from methyl or phenyl.

n is 1-5, preferably n is 1 or 2 or 3 or 5.

The number average molecular weight of the general formula (I) is 5000 to 100000, preferably 10000 to 60000, and more preferably 20000 to 40000. The number average molecular weight is a polystyrene conversion value based on a calibration curve prepared by a Gel Permeation Chromatography (GPC) apparatus using standard polystyrene. When the number average molecular weight is 5000 or less, it is difficult to obtain good mechanical properties after curing, and particularly, the elongation tends to decrease. On the other hand, when it exceeds 100000, the viscosity becomes too high, making the resin difficult to form.

Ar¹Is a component derived from a dianhydride comprising an aromatic acid anhydride and an aliphatic acid anhydride, and the aromatic acid anhydride includes an aromatic acid anhydride containing only a benzene ring, a fluorinated aromatic acid anhydride, an amide group-containing aromatic acid anhydride, an ester group-containing aromatic acid anhydride, an ether group-containing aromatic acid anhydride, a sulfur group-containing aromatic acid anhydride, a sulfone group-containing aromatic acid anhydride, a carbonyl group-containing aromatic acid anhydride, and the like.

Examples of the aromatic acid anhydride containing only a benzene ring include pyromellitic anhydride (PMDA), 2,3,3',4' -biphenyltetracarboxylic dianhydride (bpda), 3,3',4,4' -biphenyltetracarboxylic dianhydride (sBPDA), 4- (2, 5-dioxotetrahydrofuran-3-yl) -1,2,3, 4-tetrahydronaphthalene-1, 2-dicarboxylic anhydride (TDA), and the like; fluorinated aromatic anhydrides such as 6FDA 4,4' - (hexafluoroisopropylene) diphthalic anhydride; aromatic acid anhydrides containing an amide group include N, N ' - (5,5' - (perfluoropropyl-2, 2-diyl) bis (2-hydroxy-5, 1-phenylene)) bis (1, 3-dioxo-1, 3-dihydroisobenzofuran) -5-carboxamide) (6FAP-ATA), N ' - (9H-fluoren-9-ylidene-di-4, 1-phenylene) bis [1, 3-dihydro-1, 3-dioxo-5-isobenzofurancarboxamide ] (FDA-ATA), and the like; the aromatic acid anhydride containing an ester group includes p-phenyl bis (trimellitate) dianhydride (TAHQ), etc.; the aromatic acid anhydride containing an ether group includes 4,4' - (4,4' -isopropyldiphenoxy) bis (phthalic anhydride) (BPADA), 4' -oxydiphthalic anhydride (sODPA), 2,3,3',4' -diphenylether tetracarboxylic dianhydride (aODPA), 4' - (4,4' -isopropyldiphenoxy) bis (phthalic anhydride) (BPADA), etc.; the sulfur-group-containing aromatic acid anhydride includes 4,4' -bis (phthalic anhydride) sulfide (TPDA), etc.; sulfone group-containing aromatic acid anhydrides include 3,3',4,4' -diphenylsulfone tetracarboxylic acid dianhydride (DSDA) and the like; the carbonyl group-containing aromatic acid anhydride includes 3,3',4,4' -benzophenonetetracarboxylic dianhydride (BTDA) and the like.

Alicyclic acid anhydrides include 1,2,4, 5-cyclohexane tetracarboxylic dianhydride abbreviated as HPMDA, 1,2,3, 4-Butanetetracarboxylic Dianhydride (BDA), tetrahydro-1H-5, 9-methanopyrano [3,4-d ] oxanone-1, 3,6,8(4H) -Tetraone (TCA), hexahydro-4, 8-ethylene-1H, 3H-benzo [1, 2-C: 4,5-C' ] difuran-1, 3,5, 7-tetraone (BODA), cyclobutanetetracarboxylic dianhydride (CBDA), 1,2,3, 4-cyclopentanetetracarboxylic dianhydride (CpDA), etc., or an alicyclic acid anhydride having an olefin structure such as bicyclo [2.2.2] oct-7-ene-2, 3,5, 6-tetracarboxylic dianhydride (COeDA). If an acid anhydride having an ethynyl group such as 4,4' - (acetylene-1, 2-diyl) diphthalic anhydride (EBPA) is used, the mechanical strength of the light conversion layer can be further ensured by post-curing.

From the viewpoint of solubility, 4,4 '-oxydiphthalic anhydride (sODPA), 3',4,4 '-benzophenonetetracarboxylic dianhydride (BTDA), cyclobutanetetracarboxylic dianhydride (CBDA), and 4,4' - (hexafluoroisopropylidene) diphthalic anhydride (6FDA) are preferable. The above dianhydrides can be used singly or in combination of two or more.

Ar²And a component derived from a diamine which can be classified into an aromatic diamine and an aliphatic diamine, and the aromatic diamine includes an aromatic diamine containing only a benzene ring structure, a fluorinated aromatic diamine, an aromatic diamine containing an ester group, an aromatic diamine containing an ether group, an aromatic diamine containing an amide group, an aromatic diamine containing a carbonyl group, an aromatic diamine containing a hydroxyl group, an aromatic diamine containing a carboxyl group, an aromatic diamine containing a sulfone group, an aromatic diamine containing a sulfur group, and the like.

Aromatic diamines having only a benzene ring structure include m-phenylenediamine, p-phenylenediamine, 2, 4-diaminotoluene, 2, 6-diamino-3, 5-diethyltoluene, 4 '-diamino-3, 3' -dimethylbiphenyl, 9-bis (4-aminophenyl) Fluorene (FDA), 9-bis (4-amino-3-tolyl) fluorene, 2-bis (4-aminophenyl) propane, 2-bis (3-methyl-4-aminophenyl) propane, 4 '-diamino-2, 2' -dimethylbiphenyl (APB); fluorinated aromatic diamines including 2,2' -BIS (trifluoromethyl) diaminobiphenyl (TFMB), 2-BIS (4-aminophenyl) hexafluoropropane (6FDAM), 2-BIS [4- (4-aminophenoxy) phenyl ] Hexafluoropropane (HFBAPP), 2-BIS (3-amino-4-tolyl) hexafluoropropane and the like) (BIS-AF) and the like; the aromatic diamine containing an ester group includes [4- (4-aminobenzoyl) oxyphenyl ] -4-Aminobenzoate (ABHQ), di-p-aminophenyl terephthalate (BPTP), p-aminobenzoate (APAB), etc.; the aromatic diamine containing an ether group includes 2, 2-bis [4- (4-aminophenoxy) phenyl ] propane) (BAPP), 2 '-bis [4- (4-aminophenoxy phenyl) ] propane (ET-BDM), 2, 7-bis (4-aminophenoxy) -naphthalene (ET-2,7-Na), 1, 3-bis (3-aminophenoxy) benzene (TPE-M), 4' - [1, 4-phenylbis (oxy) ] bis [3- (trifluoromethyl) aniline ] (p-6FAPB), 3,4 '-diaminodiphenyl ether, 4' -diaminodiphenyl ether (ODA), 1, 3-bis (4-aminophenoxy) benzene (TPE-R), 1, 4-bis (4-aminophenoxy) benzene (TPE-Q), 4,4' -bis (4-aminophenoxy) biphenyl (BAPB), and the like; the aromatic diamine containing an amide group includes N, N ' -bis (4-aminophenyl) benzene-1, 4-dicarboxamide (BPTPA), 3,4' -diaminobenzanilide (m-APABA), 4' -Diaminobenzanilide (DABA), etc.; the aromatic diamine containing carbonyl group includes 4,4 '-diaminobenzophenone (4,4' -DABP), bis (4-amino-3-carboxyphenyl) methane (or referred to as 6,6 '-diamino-3, 3' -methylene dibenzoic acid), etc.; the hydroxyl group-containing aromatic diamine includes 3,3' -dihydroxybenzidine (HAB), 2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (6FAP), etc.; the aromatic diamine containing carboxyl group includes 6,6 '-diamino-3, 3' -methylene dibenzoic acid (MBAA), 3, 5-diaminobenzoic acid (DBA), etc.; the sulfone group-containing aromatic diamine includes 3,3' -diaminodiphenyl sulfone (DDS), 4' -diaminodiphenyl sulfone, bis [4- (4-aminophenoxy) phenyl ] sulfone (BAPS) (or 4,4' -bis (4-aminophenoxy) diphenyl sulfone), 3' -diamino-4, 4' -dihydroxydiphenyl sulfone (ABPS); the sulfur group-containing aromatic diamine includes 4,4' -diaminodiphenyl sulfide.

The aliphatic diamine is diamine without aromatic structure (such as benzene ring), the alicyclic diamine includes monocyclic alicyclic diamine, straight chain aliphatic diamine, the straight chain aliphatic diamine includes silicon oxygen type diamine, linear alkyl diamine, and linear aliphatic diamine containing ether group, the monocyclic alicyclic diamine includes 4,4' -diaminodicyclohexylmethane (PACM), 3-dimethyl-4, 4-diaminodicyclohexylmethane (DMDC); the silicone type diamine (also called amino modified silicone) includes alpha, omega- (3-aminopropyl) polysiloxane (KF8010), X22-161A, X22-161B, NH15D, 1, 3-bis (3-aminopropyl) -1,1,3, 3-tetramethyldisiloxane (PAME), etc.; the number of carbon atoms of the linear alkyl diamine is 6-12, and the linear alkyl diamine without a substituent is preferred; the ether group-containing linear aliphatic diamine includes ethylene glycol di (3-aminopropyl) ether and the like.

The diamine can also be selected from diamine containing fluorenyl, wherein fluorenyl has huge free volume and rigid condensed ring structure, and can ensure that polyimide has good heat resistance, thermal oxidation stability, mechanical property, optical transparency and good solubility in organic solvent, and the diamine containing fluorenyl, such as 9, 9-bis (3, 5-difluoro-4-aminophenyl) fluorene, which can be obtained by the reaction of 9-fluorenone and 2, 6-dichloroaniline. The fluorinated diamine can also be 1, 4-bis (3 '-amino-5' -trifluoromethylphenoxy) biphenyl, the diamine is meta-substituted fluorine-containing diamine with a rigid biphenyl structure, the meta-substituted structure can block charge flow along the molecular chain direction, and the intermolecular conjugation effect is reduced, so that the absorption of visible light to light is reduced, and the diamine or anhydride with an asymmetric structure can improve the transparency of the organic silicon modified polyimide resin composition to a certain extent. The above diamines may be used alone or in combination of two or more.

Examples of the diamine having an active hydrogen include diamines having a hydroxyl group such as 3,3 '-diamino-4, 4' -dihydroxybiphenyl, 4 '-diamino-3, 3' -dihydroxy-1, 1 '-biphenyl (or referred to as 3,3' -dihydroxybiphenylamine) (HAB), 2-bis (3-amino-4-hydroxyphenyl) propane (BAP), 2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (6FAP), 1, 3-bis (3-hydroxy-4-aminophenoxy) benzene, 1, 4-bis (3-hydroxy-4-aminophenyl) benzene, 3 '-diamino-4, 4' -dihydroxydiphenyl sulfone (ABPS) can be exemplified, as the diamine having a carboxyl group, 3, 5-diaminobenzoic acid, bis (4-amino-3-carboxyphenyl) methane (otherwise known as 6,6 '-diamino-3, 3' -methylenedibenzoic acid), 3, 5-bis (4-aminophenoxy) benzoic acid, 1, 3-bis (4-amino-2-carboxyphenoxy) benzene are exemplified. Diamines having an amino group include, for example, 4' -Diaminobenzanilide (DABA), 2- (4-aminophenyl) -5-aminobenzimidazole, diethylenetriamine, 3,3' -diaminodipropylamine, triethylenetetramine, and N, N ' -bis (3-aminopropyl) ethylenediamine (or N, N-bis (3-aminopropyl) ethylethylamine). Diamines containing thiol groups, for example 3, 4-diaminobenzenethiol. The above diamines may be used alone or in combination of two or more.

The organic silicon modified polyimide can be synthesized by a known synthesis method. Dianhydrides and diamines can be produced by dissolving them in an organic solvent for imidization in the presence of a catalyst, examples of which include acetic anhydride/triethylamine type, valerolactone/pyridine type, etc., preferably, water generated by an azeotropic process in imidization, and removal of water is promoted by using a dehydrating agent such as toluene.

In other embodiments, a small portion of amic acid can be present in the main chain of the polyimide, for example, the ratio of amic acid to imide in the polyimide molecule is 1-3: 100, and there is an interaction force between amic acid and epoxy resin, so that the substrate has superior performance. In other embodiments, the substrate can also be obtained by adding solid materials (such as thermal curing agent, inorganic heat-dissipating particles and phosphor) in the state of polyamic acid. In addition, the alicyclic anhydride and the diamine can be directly heated and dehydrated to obtain the solubilized polyimide, and the solubilized polyimide is used as a glue material, has good light transmittance and is liquid, so that other solid substances (such as inorganic heat dissipation particles and fluorescent powder) can be more fully dispersed in the glue material.

In the reaction of the anhydride and the diamine, when the main chain of the anhydride contains carbon-carbon triple bonds, the bonding force of the carbon-carbon triple bonds can strengthen the molecular structure of the anhydride; or a diamine containing a vinyl siloxane structure.

The molar ratio of dianhydride to diamine is 1: 1. Wherein the molar fraction of the diamine containing active hydrogen functional groups in the whole diamine is 5-25%.

The silicone-modified polyimide can be classified into two types, i.e., fluorinated aromatic silicone-modified polyimide and aliphatic silicone-modified polyimide. The fluorinated aromatic silicone-modified polyimide is synthesized from a silicone-type diamine, an aromatic diamine having a fluorine (F) group (or referred to as an F-substituted aromatic diamine), and an aromatic dianhydride having a fluorine (F) group (or referred to as an F-substituted aromatic anhydride); the aliphatic organosilicon modified polyimide is synthesized by dianhydride, silicon-oxygen type diamine and at least one diamine (also called aliphatic diamine) without aromatic structures (such as benzene rings), or the diamine (one diamine is silicon-oxygen type diamine) and at least one dianhydride (also called aliphatic anhydride) without aromatic structures (such as benzene rings), the aliphatic organosilicon modified polyimide comprises semi-aliphatic organosilicon modified polyimide and full-aliphatic organosilicon modified polyimide, and the full-aliphatic organosilicon modified polyimide is synthesized by at least one aliphatic dianhydride, silicon-oxygen type diamine and at least one aliphatic diamine; at least one aliphatic dianhydride or aliphatic diamine is used in the raw materials for synthesizing the semi-aliphatic organic silicon modified polyimide. The raw materials required for synthesizing the organic silicon modified polyimide and the silicon oxygen content of the organic silicon modified polyimide have certain influence on the transmittance, the color change performance, the mechanical performance, the warping degree and the refractive index of the base material.

The silicone-modified polyimide of the present invention has a siloxane content of 20 to 75 wt%, preferably 30 to 70 wt%, a glass transition temperature of 150 ℃ or lower, and the glass transition temperature (Tg) is measured by using TMA-60 manufactured by shimadzu corporation, a thermal curing agent, and the test conditions are as follows: loading: 5 g; temperature rise rate: 10 ℃/min; measuring the atmosphere: a nitrogen atmosphere; nitrogen flow rate: 20 ml/min; measurement temperature range: -40 to 300 ℃. When the siloxane content is less than 20%, a film made of the silicone-modified polyimide resin composition may become very hard and brittle due to the filling of the phosphor and the thermally conductive filler, and also warp after drying and curing, resulting in low processability; in addition, the resistance to thermal discoloration is reduced; when the siloxane content is more than 75%, the film made of the silicone-modified polyimide resin composition becomes cloudy, the light transmittance decreases, and the tensile strength of the film decreases. The content of siloxane in the invention is the weight ratio of silicon-oxygen type diamine (the structural formula is shown as formula (A)) to organic silicon modified polyimide, and the weight of the organic silicon modified polyimide is the sum of the weight of diamine and dianhydride used for synthesizing the organic silicon modified polyimide minus the weight of water generated in the synthesis process.

R in the formula (A) is selected from methyl or phenyl; r is preferably methyl, and n is 1-5, preferably 1,2,3, 5.

The organic solvent required for synthesizing the silicone-modified polyimide may be one that can dissolve the silicone-modified polyimide and ensure affinity (wettability) with the phosphor or filler to be added, but a large amount of the solvent is not left in the product, and the solvent is generally used in an amount of 1mol when the number of moles of the solvent is equal to the number of moles of water formed from the diamine and the acid anhydride, for example, 1mol of water formed from 1mol of the diamine and 1mol of the acid anhydride. In addition, the boiling point of the selected organic solvent at normal atmospheric pressure is 80 ℃ or higher and less than 300 ℃, more preferably 120 ℃ or higher and less than 250 ℃. Since drying and curing at a low temperature are required after coating, if the temperature is lower than 120 ℃, during the implementation of the coating process, it may not be well coated because the drying speed is too fast. If the boiling temperature of the organic solvent is selected to be higher than 250 deg.C, drying at a low temperature may be delayed. Specifically, the organic solvent is an ether organic solvent, an ester organic solvent, dimethyl ether, a ketone organic solvent, an alcohol organic solvent, an aromatic hydrocarbon solvent or the like. The ether organic solvent comprises ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether and propylene glycol monoethyl ether; the ester organic solvent comprises acetate, the acetate comprises ethylene glycol monoethyl ether acetate and diethylene glycol monobutyl ether acetate, and the ester solvent can also be methyl lactate, ethyl lactate and butyl ester; dimethyl ether solvents include triglyme or tetraglyme; the ketone solvent comprises methyl butyl ketone, methyl isobutyl ketone, cyclopentanone or 2-heptanone; the alcohol solvent comprises butanol, isobutanol, 3-methyl-3-methoxybutanol or diacetone alcohol; the aromatic hydrocarbon solvent includes toluene or xylene; other solvents include gamma-butyrolactone, N-methylpyrrolidone, N-dimethylacetamide or dimethylsulfoxide.

The invention provides an organic silicon modified polyimide resin composition which comprises the organic silicon modified polyimide and a thermal curing agent, wherein the thermal curing agent is epoxy resin, isocyanate or a bisoxazoline compound. In one embodiment, the amount of the thermal curing agent is 5 to 12% of the weight of the silicone modified polyimide based on the weight of the silicone modified polyimide. The organic silicon modified polyimide resin composition can further comprise heat dissipation particles and fluorescent powder.

Light transmittance

Factors affecting the light transmittance of the silicone-modified polyimide resin composition are at least the type of the main material, the type of the modifier (thermal curing agent), the type and content of the heat-dissipating particles, and the siloxane content. The light transmittance refers to the transmittance of light in the vicinity of the main light-emitting wavelength range of the LED chip, for example, in the vicinity of 450nm in the main light-emitting wavelength range of a blue LED chip, the absorbance of the composition or polyimide in the vicinity of 450nm is low enough or even not absorbed, so that most or all of the light can be ensured to pass through the composition or polyimide. In addition, when light emitted by the LED chip passes through the interface of the two substances, the closer the refractive indexes of the two substances are, the higher the light extraction efficiency is, the refractive index of the substance (such as the solid crystal glue) contacting with the filament substrate (or the base layer) is, so that the refractive index of the organic silicon modified polyimide composition is 1.4-1.7, preferably 1.4-1.55. The organic silicon modified polyimide resin composition is used for a filament substrate, and needs to have good light transmittance at the peak wavelength of InGaN of a blue excitation white LED. In order to obtain good transmittance, the raw materials for synthesizing the organic silicon modified polyimide, the thermal curing agent and the heat dissipation particles can be changed, and since the fluorescent powder in the organic silicon modified polyimide resin composition has a certain influence on the transmittance test, the organic silicon modified polyimide resin composition for measuring the transmittance does not contain the fluorescent powder, and the transmittance of the organic silicon modified polyimide resin composition is 86-93%, preferably 88-91%, or preferably 89-92%, or preferably 90-93%.

The acid anhydride and the diamine react to form the polyimide, wherein the acid anhydride and the diamine can be respectively selected from different compositions, namely, the polyimides formed by the reaction of different acid anhydrides and different diamines have different light transmittances. The aliphatic organic silicon modified polyimide resin composition comprises aliphatic organic silicon modified polyimide and a thermal curing agent, and the F-type aromatic organic silicon modified polyimide resin composition comprises F-type aromatic organic silicon modified polyimide and a thermal curing agent. The aliphatic silicone-modified polyimide resin composition has a high light transmittance because the aliphatic silicone-modified polyimide has an alicyclic structure. In addition, the fluorinated aromatic, semi-aliphatic and fully aliphatic polyimides have good light transmittance for blue LED chips. The fluorinated aromatic silicone-modified polyimide is synthesized from a silicone-type diamine, an aromatic diamine having a fluorine (F) group (or referred to as an F-substituted aromatic diamine), and an aromatic dianhydride having a fluorine (F) group (or referred to as an F-substituted aromatic anhydride), that is, Ar¹And Ar²Both of which have fluorine (F) groups. The semi-aliphatic and full-aliphatic organosilicon modified polyimide is synthesized by dianhydride, silicon-oxygen type diamine and at least one diamine (or called aliphatic diamine) without aromatic structures (such as benzene rings), or synthesized by diamine (one of which is silicon-oxygen type diamine) and at least one dianhydride (or called aliphatic anhydride) without aromatic structures (such as benzene rings), namely Ar¹And Ar²At least one of the two is an alicyclic hydrocarbon structure.

Although the main emission wavelength of the blue LED chip is 450nm, the blue LED chip may emit a small amount of light with a short wavelength of about 400nm due to the difference in the process conditions of the chip and the influence of the environment. The absorption rates of fluorinated aromatic, semi-aliphatic and fully aliphatic polyimides are different for light with a short wavelength of 400nm, and the absorption rate of the fluorinated aromatic polyimide for light with a short wavelength of about 400nm is about 20%, that is, the light transmittance of light with a wavelength of 400nm through the fluorinated aromatic polyimide is about 80%. The absorbance of the semi-aliphatic and fully aliphatic polyimides at a short wavelength of 400nm is lower than that of the fluorinated aromatic polyimides at a short wavelength of around 400nm, and the absorbance is only about 12%. Therefore, in one embodiment, if the LED chip used in the LED filament has a uniform quality and emits less blue light with a short wavelength, the fluorinated aromatic silicone modified polyimide can be used to fabricate the filament substrate or the light conversion layer. In another embodiment, if the LED chips used in the LED filament have different qualities and emit more blue light with short wavelength, the filament substrate or the light conversion layer can be made of semi-aliphatic or full-aliphatic silicone modified polyimide.

The addition of different thermal curing agents has different effects on the light transmittance of the organic silicon modified polyimide. Table 1-1 shows the effect of adding different thermal curing agents on the light transmittance of the all-aliphatic silicone modified polyimide, and under the condition that the main light-emitting wavelength of a blue LED chip is 450nm, the light transmittance of the all-aliphatic silicone modified polyimide is not significantly different by adding different thermal curing agents, but under the condition that the main light-emitting wavelength is 380nm, the light transmittance of the all-aliphatic silicone modified polyimide is affected by adding different thermal curing agents. The transmittance of the silicone-modified polyimide itself for light having a short wavelength (380nm) is inferior to that for light having a long wavelength (450nm), but the degree of difference varies depending on the addition of different thermosetting agents. For example, when the full-aliphatic silicone modified polyimide is added with the thermal curing agent KF105, the degree of decrease in light transmittance is small, but when the full-aliphatic silicone modified polyimide is added with the thermal curing agent 2021p, the degree of decrease in light transmittance may be large. Therefore, in one embodiment, if the LED chip used for the LED filament has a uniform quality and emits less blue light with a short wavelength, the thermal curing agent BPA or 2021p may be added. In contrast, in an embodiment, if the LED filament has different LED chip qualities and emits more blue light with short wavelength, the thermal curing agent KF105 may be optionally added. Tables 1-1 and 1-2 were each subjected to a light transmittance test using Shimadzu UV-1800. It has light transmittance at wavelengths of 380nm, 410nm and 450nm, respectively, according to the light emission of the white LED.

TABLE 1-1

Even if the same thermosetting agent is added, the light transmittance is affected differently when the amount of the thermosetting agent added is different. Tables 1-2 show that the light transmittance is improved when the addition amount of the heat-curing agent BPA of the all-aliphatic silicone-modified polyimide is increased from 4% to 8%. However, when the addition amount is further increased to 12%, the light transmittance is hardly exhibited. It was shown that the light transmittance became better as the amount of the heat-curing agent added increased, but when the amount was increased to a certain extent, the effect of adding more heat-curing agent on the light transmittance was considerably limited.

Tables 1 to 2

TABLE 2

Different heat-dissipating particles have different transmittances, and if the heat-dissipating particles with low transmittances or low light reflectivities are used, the light transmittance of the organic silicon modified polyimide resin composition is reduced. The heat-dissipating particles in the silicone-modified polyimide resin composition of the present invention are preferably transparent powders, or particles with high transmittance, or particles with high light reflectance, because the LED soft filament is mainly used for light emission, and thus the filament substrate needs to have good transmittance. In the case where two or more types of heat-dissipating particles are mixed, particles having high transmittance and particles having low transmittance are used in combination, and the proportion of the particles having high transmittance is made larger than that of the particles having low transmittance. For example, in one embodiment, the weight ratio of the particles with high transmittance to the particles with low transmittance is 3-5: 1.

Different siloxane contents also have an effect on light transmission. As can be seen from Table 2, the light transmission was only 85% at a siloxane content of only 37% by weight, but the light transmission was shown at a level of more than 94% as the siloxane content increased to more than 45%.

Heat resistance

Factors affecting the heat resistance of the silicone-modified polyimide resin composition are at least the type of main material, the silicone content, and the type and content of a modifier (thermal curing agent).

The organic silicon modified polyimide resin composition synthesized by organic silicon modified polyimide with fluorinated aromatic, semi-aliphatic and full aliphatic has excellent heat resistance, and is suitable for manufacturing filament substrates or light conversion layers. If carefully distinguished again, it was found that the fluorinated aromatic silicone-modified polyimide had better heat resistance properties than the aliphatic silicone-modified polyimide in the accelerated heat aging test (300 ℃ C.. times.1 hr). Therefore, in one embodiment, if the LED filament uses a high-power and high-brightness LED chip, the filament substrate or the light conversion layer can be made of fluorinated aromatic silicone modified polyimide.

The high or low siloxane content in the silicone-modified polyimide can affect the thermochromic resistance of the silicone-modified polyimide resin composition. The resistance to thermal discoloration means that the sample was left to stand at 200 ℃ for 24 hours, and the transmittance at a wavelength of 460nm of the sample after the standing was measured. As can be seen from Table 2, the transmittance after 200 ℃ C.. times.24 hours was only 83% when the siloxane content was only 37% by weight, the transmittance after 200 ℃ C.. times.24 hours was gradually increased as the siloxane content was increased, and the transmittance after 200 ℃ C.. times.24 hours was as high as 95% when the siloxane content was 73% by weight, so that increasing the siloxane content was effective in improving the thermal discoloration resistance of the silicone-modified polyimide.

When the organosilicon modified polyimide and the thermal curing agent are subjected to crosslinking reaction, the thermal curing agent only needs to have an organic group capable of reacting with an active hydrogen functional group in the polyimide, and the dosage and the type of the thermal curing agent have certain influence on the color change performance, the mechanical performance and the refractive index of the substrate, so that some thermal curing agents with better heat resistance and transmittance can be selected, and examples of the thermal curing agent comprise epoxy resin, isocyanate, bismaleimide or bisoxazoline compounds. The epoxy resin may be a bisphenol A type epoxy resin, such as BPA, and may also be a silicone type epoxy resin, such as KF105, X22-163, X22-163A, and may also be an alicyclic epoxy resin, such as 3, 4-epoxycyclohexylmethyl 3, 4-epoxycyclohexylformate (2021P), EHPE3150 CE. Through the bridging reaction of the epoxy resin, a three-dimensional bridging structure is formed between the organic silicon modified polyimide and the epoxy resin, and the structural strength of the rubber material is improved. In one embodiment, the amount of the thermal curing agent used can also be determined according to the molar amount of the thermal curing agent reacting with the active hydrogen functional groups in the silicone modified polyimide. In one embodiment, the molar amount of active hydrogen functional groups reacted with the thermal curing agent is equal to the molar amount of the thermal curing agent, e.g., 1mol of active hydrogen functional groups reacted with the thermal curing agent, the molar amount of the thermal curing agent is 1 mol.

Thermal conductivity

Factors influencing the thermal conductivity of the organic silicon modified polyimide resin composition include at least the type and content of fluorescent powder, the type and content of heat dissipation particles and the addition and type of coupling agent. Among them, the particle size and particle size distribution of the heat dissipating particles also affect the thermal conductivity.

The organic silicon modified polyimide resin composition may further contain a phosphor for obtaining a desired light emitting characteristic, and the phosphor may convert the wavelength of light emitted from the light emitting semiconductor, for example, a yellow phosphor may convert blue light into yellow light, and a red phosphor may convert blue light into red light. Yellow phosphors, e.g. (Ba, Sr, Ca)₂SiO₄:Eu、(Sr,Ba)₂SiO₄Eu (barium orthosilicate (BOS)) and the like transparent phosphor, Y₃Al₅O₁₂Ce (yttrium aluminum garnet) and Tb₃Al₃O₁₂Silicate phosphors having a silicate structure such as Ce (yttrium aluminum garnet) and oxynitride phosphors such as Ca-. alpha. -SiAlON. Red wineThe color phosphor comprises a nitride phosphor, such as CaAlSiN₃:Eu、CaSiN₂Eu. Green phosphors such as rare earth-halide phosphors, silicate phosphors, and the like. The content ratio of the phosphor in the silicone-modified polyimide resin composition can be arbitrarily set according to the desired light emission characteristics. In addition, since the thermal conductivity of the phosphor is much higher than that of the silicone-modified polyimide resin, the thermal conductivity of the entire silicone-modified polyimide resin composition is also improved as the content ratio of the phosphor in the silicone-modified polyimide resin composition is improved. Therefore, in one embodiment, on the premise of satisfying the light emitting characteristics, the content of the phosphor can be moderately increased to increase the thermal conductivity of the silicone modified polyimide resin composition, which is beneficial to the heat dissipation property of the filament substrate or the light conversion layer. When the silicone-modified polyimide resin composition is used as a filament substrate, the content, shape, and particle size of the phosphor in the silicone-modified polyimide resin composition also have a certain influence on the mechanical properties (e.g., elastic modulus, elongation, tensile strength) and the degree of warpage of the substrate. In order to make the base material have better mechanical property, thermal conductivity and small warping degree, the fluorescent powder contained in the organic silicon modified polyimide resin composition is granular, the shape of the fluorescent powder can be spherical, plate-shaped or needle-shaped, and the shape of the fluorescent powder is preferably spherical; the phosphor has a maximum average length (average particle diameter in a spherical shape) of 0.1 μm or more, preferably 1 μm or more, more preferably 1 to 100 μm, and still more preferably 1 to 50 μm; the amount of the phosphor is not less than 0.05 times, preferably not less than 0.1 times, and not more than 8 times, and preferably not more than 7 times the weight of the silicone-modified polyimide, for example, the weight of the silicone-modified polyimide is 100 parts by weight, the amount of the phosphor is not less than 5 parts by weight, preferably not less than 10 parts by weight, and not more than 800 parts by weight, and preferably not more than 700 parts by weight, and when the amount of the phosphor in the silicone-modified polyimide resin composition exceeds 800 parts by weight, the mechanical properties of the silicone-modified polyimide resin composition may not reach the strength required as a filament base layer, resulting in an increase in the fraction defective of the product. In one embodiment, two phosphors are added simultaneously in proportionWhen the red phosphor and the green phosphor are simultaneously added, the addition ratio of the red phosphor to the green phosphor is 1: 5-8, and the addition ratio of the red phosphor to the green phosphor is preferably 1: 6-7. In another embodiment, two phosphors are added simultaneously, for example, when red phosphor and yellow phosphor are added simultaneously, the ratio of red phosphor to yellow phosphor is 1: 5-8, preferably 1: 6-7. In other embodiments, three or more phosphors may be added simultaneously.

The purpose of adding the heat dissipation particles is mainly to increase the heat conductivity of the organic silicon modified polyimide resin composition, maintain the luminous color temperature of the LED chip and prolong the service life of the LED chip. Examples of the heat dissipating particles include silica, alumina, magnesia, magnesium carbonate, aluminum nitride, boron nitride, diamond, or the like. From the viewpoint of dispersibility, silica, alumina, or a combination of both thereof is preferably used. The heat dissipating particles may be spherical or block-like, and the spherical shape includes a shape similar to the spherical shape, and in one embodiment, spherical and non-spherical heat dissipating particles may be used to ensure the dispersibility of the heat dissipating particles and the thermal conductivity of the base material, and the weight ratio of the spherical to non-spherical heat dissipating particles is 1: 0.15-0.35.

Table 3-1 shows the relationship between the content of heat dissipating particles and the thermal conductivity of the silicone modified polyimide resin composition, and the thermal conductivity of the silicone modified polyimide resin composition increases with the increase of the content of heat dissipating particles, but when the content of heat dissipating particles in the silicone modified polyimide resin composition exceeds 1200 parts by weight, the mechanical properties of the silicone modified polyimide resin composition may not reach the strength required as a filament base layer, resulting in an increase in the fraction defective of the product. In one embodiment, high-content and high-transmittance or high-reflectivity heat-dissipating particles (e.g., SiO) can be added₂、Al₂O₃) The light transmittance of the silicone-modified polyimide resin composition can be maintained, and the heat dissipation of the silicone-modified polyimide resin composition can be improved. Tables 3-1 and 3-2 show the obtained silicone-modified polyimide resin composition cut into a film thickness of 300. mu.m, a diameter of 30mmThe circle of (a) was used as a test piece, and the thermal conductivity was measured by a thermal conductivity measuring apparatus DRL-III manufactured in Hunan science, under the following test conditions: hot plate temperature: 90 ℃; cold electrode temperature: 20 ℃; loading: 350N.

TABLE 3-1

The weight ratio is [ wt%]

0.0％

37.9％

59.8％

69.8％

77.6％

83.9％

89.0％

The volume ratio is [ vol%]

0.0％

15.0％

30.0％

40.0％

50.0％

60.0％

70.0％

Thermal conductivity [ W/m.K ]]

0.17

0.20

0.38

0.54

0.61

0.74

0.81

TABLE 3-2

Specification of	①	②	③	④	⑤	⑥	⑦
								Average particle diameter [ mu ] m]	2.7	6.6	9.0	9.6	13	4.1	12
Particle size distribution [ mu m ]]	1～7	1～20	1～30	0.2～30	0.2～110	0.1～20	0.1～100
								Thermal conductivity [ W/m.K ]]	1.65	1.48	1.52	1.86	1.68	1.87	2.10

For the influence of the particle size and distribution of the heat dissipating particles on the thermal conductivity of the silicone modified polyimide resin composition, please refer to table 3-2 and fig. 4. Tables 3-2 and fig. 4 show the results of adding 7 kinds of heat dissipating particles with different specifications in the same ratio to the silicone modified polyimide resin composition and the influence on the thermal conductivity thereof. The particle size of the heat-dissipating particles suitable for addition to the silicone-modified polyimide resin composition can be roughly classified into a small particle size (less than 1 μm), a medium particle size (1 to 30 μm), and a large particle size (greater than 30 μm).

The first specification, the second specification and the third specification are compared, and the first specification, the second specification and the third specification are all only added with heat dissipation particles with medium particle size and are different from each other in average particle size. The results show that the average particle size of the heat-dissipating particles does not significantly affect the thermal conductivity of the silicone-modified polyimide resin composition when only the heat-dissipating particles having a medium particle size are added. Comparison of the specification (c) and (c) shows that the addition of the specification (c) having a small particle size and a medium particle size under the condition of similar average particle sizes exhibits a thermal conductivity significantly superior to the addition of the specification (c) having only a medium particle size. Comparison of the specifications (a) and (b) shows that, in the case where both the small particle size and the medium particle size are added, the average particle size of the heat-dissipating particles is different, but there is no significant influence on the thermal conductivity of the silicone-modified polyimide resin composition. Comparison of the specifications (c) and (c) shows that the specification (c) of adding a large-sized heat dissipating particle in addition to a small-sized heat dissipating particle and a medium-sized heat dissipating particle has the most excellent thermal conductivity. The specifications are compared with the specification of the fifth part and the seventh part, and although the heat dissipation particles with large, medium and small particle sizes are added in the specifications of the fifth part and the seventh part, the average particle size is similar, the thermal conductivity of the specification of the seventh part is obviously superior to that of the specification of the fifth part, and the reason for the difference is related to the proportion of particle size distribution. Referring to the particle size distribution of fig. 4, the curve of the specification (c) is smooth, the slope is mostly very small, and it is shown that the specification (c) includes not only each particle size, but also each particle size content has a proper proportion, and the particle size distribution is normal, for example, the small particle size content is about 10%, the medium particle size content is about 60%, and the large particle size content is about 30%. Reversely viewing the specification, the curve of the specification has two areas with large slopes, the areas are respectively in the particle size of 1-2 μm and the particle size of 30-70 μm, which means that most of the particle size of the specification is distributed in the particle size of 1-2 μm and the particle size of 30-70 μm, only a small amount of heat dissipation particles with the particle size of 3-20 μm are contained, and the two areas are distributed.

Therefore, the degree of influence of the particle size distribution of the heat dissipating particles on the thermal conductivity is larger than the average particle size of the heat dissipating particles, and the silicone modified polyimide resin has the best thermal conductivity when the heat dissipating particles with three kinds of particle sizes, namely large, medium and small, are added, and the content of the small particle size is about 5-20%, the content of the medium particle size is about 50-70%, and the content of the large particle size is about 20-40%. Because the heat dissipation particles are densely packed and contacted to form an efficient heat dissipation path in the same volume under the condition of three kinds of particle sizes, namely large, medium and small particle sizes.

In one embodiment, for example, alumina with a particle size distribution of 0.1-100 μm and an average particle size of 12 μm or alumina with a particle size distribution of 0.1-20 μm and an average particle size of 4.1 μm is used, wherein the particle size distribution is within the particle size range of alumina. In another embodiment, the average particle size is 1/5 to 2/5, preferably 1/5 to 1/3, of the thickness of the substrate in view of the smoothness of the substrate. The amount of the heat dissipation particles is 1-12 times of the weight (amount) of the organosilicon modified polyimide, for example, 100 parts by weight of the organosilicon modified polyimide, 100-1200 parts by weight of the heat dissipation particles, preferably 400-900 parts by weight of the heat dissipation particles, two kinds of heat dissipation particles are simultaneously added, for example, silicon dioxide and aluminum oxide are simultaneously added, and the weight ratio of the aluminum oxide to the silicon dioxide is 0.4-25: 1, preferably 1-10: 1.

When the organic silicon modified polyimide resin composition is synthesized, the adhesion between solid substances (such as fluorescent powder and heat dissipation particles) and a glue material (such as organic silicon modified polyimide) can be improved by adding a coupling agent (such as a silane coupling agent), the dispersion uniformity of the whole solid substances can be improved, and further the heat dissipation performance and the mechanical strength of a light conversion layer can be improved. The amount of the coupling agent is related to the amount of the heat dissipating particles added and the specific surface area thereof, and the amount of the coupling agent is (the amount of the heat dissipating particles is the specific surface area of the heat dissipating particles)/the minimum coating area of the coupling agent, for example, an epoxy titanate coupling agent is used, and the amount of the coupling agent is (the amount of the heat dissipating particles is the specific surface area of the heat dissipating particles)/331.5.

In other embodiments of the present invention, in order to further improve the properties of the silicone-modified polyimide resin composition in the synthesis process, additives such as a defoaming agent, a leveling agent or an adhesive may be optionally added during the synthesis process of the silicone-modified polyimide resin composition, as long as they do not affect the optical rotation resistance, mechanical strength, heat resistance and discoloration of the product. The defoaming agent is used for eliminating bubbles generated at the time of printing, coating and curing, and for example, an acrylic or silicone based surfactant is used as the defoaming agent. The leveling agent is used to eliminate irregularities on the surface of the coating film generated during printing and coating. Specifically, the composition preferably contains 0.01 to 2 wt% of a surfactant component, can suppress bubbles, can smooth a coating film by using a leveling agent such as an acrylic or silicone type, and preferably contains no ionic impurities. Examples of the binder include imidazole compounds, thiazole compounds, triazole compounds, organoaluminum compounds, organotitanium compounds, and silane coupling agents. Preferably, these additives are used in an amount of not more than 10% by weight based on the silicone-modified polyimide. When the blending amount of the additive exceeds 10% by weight, the physical properties of the resulting coating film tend to be lowered, and there also arises a problem of deterioration in optical rotation resistance caused by volatile components.

Mechanical strength

The factors influencing the mechanical strength of the organic silicon modified polyimide resin composition are at least the type of main material, the content of siloxane, the type of modifier (thermal curing agent), the content of fluorescent powder and the content of heat dissipation particles.

Different silicone-modified polyimide resins possess different properties, and table 4 shows the main properties of three silicone-modified polyimides, fluorinated aromatic, semi-aliphatic and fully aliphatic, respectively, at a siloxane content of about 45% (wt%). Fluorinated aromatics possess the best resistance to thermal discoloration, while full-aliphatic have the best light transmittance. The fluorinated aromatics have both higher tensile strength and elastic modulus. The mechanical strength test conditions shown in tables 4 to 6 were: the silicone-modified polyimide resin composition had a thickness of 50 μm and a width of 10mm, and the tensile properties of the film were measured using ISO527-3:1995 standard at a tensile rate of 10 mm/min.

TABLE 4

When the filament is manufactured, the LED chip and the electrode are fixed on the filament substrate formed by the organic silicon modified polyimide resin composition through the die bond adhesive, then the routing procedure is carried out, and the adjacent LED chip, the LED chip and the electrode are electrically connected through the conducting wire. In order to ensure the quality of die bonding and wire bonding and improve the product quality, the elastic modulus of the filament substrate should have a certain level to resist the downward pressure of the die bonding and wire bonding processes, so the elastic modulus of the filament substrate should be greater than 2.0Gpa, preferably 2-6 Gpa, and most preferably 4-6 Gpa. Table 5 shows the effect of varying siloxane content and the presence or absence of particle (phosphor and alumina) addition on the elastic modulus of silicone modified polyimide resin compositions. Under the condition that fluorescent powder and alumina particles are not added, the elastic modulus of the organic silicon modified polyimide resin composition is less than 2.0Gpa, and the elastic modulus is reduced along with the increase of the siloxane content, namely the organic silicon modified polyimide resin composition is softened. However, the elastic modulus of the organosilicon modified polyimide resin composition can be greatly improved and is more than 2.0GPa under the condition of adding the fluorescent powder and the alumina particles. Therefore, the increase in the siloxane content can soften the silicone-modified polyimide resin composition, facilitating the addition of more fillers, such as more phosphors or heat-dissipating particles. In order to provide the base material with excellent elastic modulus and thermal conductivity, the particle size distribution and mixing ratio of the heat dissipating particles may be appropriately selected so that the average particle size is in the range of 0.1 μm to 100 μm, or in the range of 1 μm to 50 μm.

In order to make the LED filament have better bending performance, the elongation at break of the filament substrate should be greater than 0.5%, preferably 1 to 5%, and most preferably 1.5 to 5%. Referring to table 5, the silicone modified polyimide resin composition has excellent elongation at break without adding phosphor and alumina particles, and the elongation at break increases with increasing siloxane content, and the elastic modulus decreases with decreasing, thereby reducing the occurrence of warpage. On the contrary, in the case where the phosphor and the alumina particles are added, the silicone-modified polyimide resin composition exhibits a decrease in elongation at break, an increase in elastic modulus, and an increase in warpage.

TABLE 5

The addition of the thermal curing agent can improve the heat resistance and glass transition temperature of the organic silicon modified polyimide resin, and can also improve the mechanical properties of the organic silicon modified polyimide resin, such as tensile strength, elastic modulus and elongation at break. And different heat curing agents are added, so that different promotion effects can be achieved. Table 6 shows the effect of the silicone-modified polyimide resin composition showing different tensile strength and elongation at break after the addition of different heat curing agents. The full aliphatic organic silicon modified polyimide has better tensile strength after the thermal curing agent EHPE3150 is added, and has better elongation when the thermal curing agent KF105 is added.

TABLE 6

Table 7: specific information of BPA

Table 8: 2021P details of

Table 9: specific information of EHPE3150 and EHPE3150CE

Table 10: the refractive index can be called refractive index, and the specific information of PAME, KF8010, X22-161A, X22-161B, NH15D, X22-163, X22-163A and KF-105.

The silicone-modified polyimide resin composition of the present invention can be used as a base material in the form of a film or attached to a support. The film formation process includes three steps, (a) a coating step: spreading the organic silicon modified polyimide resin composition on a stripping body, and coating to form a film; (b) a drying and heating procedure: heating and drying the film together with the peeling body to remove the solvent in the film; (c) stripping: after completion of the drying, the film was peeled from the peeled body to obtain a film-form silicone-modified polyimide resin composition. The peeling body may be a centrifugal film or other material that does not chemically react with the silicone-modified polyimide resin composition, and for example, a PET centrifugal film may be used.

As the coating method in the coating step, a roll-to-roll type coating apparatus such as a roll coater, a die coater, a knife coater, or the like, or a simple coating method such as a printing method, an ink jet method, a dispensing method, a spray method, or the like can be used.

The drying method corresponding to the above-mentioned heat drying step may be selected from a vacuum drying method, a heat drying method and the like. The heating method may be a heat radiation method in which heat is generated by heating a heat source such as an electric heater or a heat medium to generate indirect convection, or infrared rays emitted from the heat source are used for heating.

The above silicone-modified polyimide resin composition can be dried and cured after coating to obtain a high thermal conductive film (composite film) to obtain a film having the characteristics of any one or a combination of the following: excellent light transmission, chemical resistance, heat resistance, thermal conductivity, film mechanical properties and optical rotation resistance.

In one embodiment, the amidation reaction is performed in a nitrogen atmosphere, or a vacuum defoaming method or both methods are used during the synthesis of the organic silicon modified polyimide resin composition, so that the volume percentage of the cells in the organic silicon modified polyimide resin composition composite film is 5-20%, preferably 5-10%. As shown in fig. 5B, the silicone modified polyimide resin composition composite film was used as a substrate of an LED soft filament (as in the various LED filament examples described above), the substrate 420B had an upper surface 420B1 and an opposite lower surface 420B2, and fig. 5A shows the surface morphology of the substrate obtained by spraying gold on the surface of the substrate and observing it under a vega3 electron microscope of Tescan corporation. As can be seen from the SEM images of the substrate surfaces shown in fig. 5B and 5A, there are cells 4d in the substrate, the volume percentage of the cells 4d in the substrate 420B is 5-20%, preferably 5-10%, the cross section of the cells 4d is irregular, as shown in fig. 5B, the cross section of the substrate 420B is shown schematically, the dotted line in fig. 5B is a reference line, the upper surface 420B1 of the substrate includes a first region 4a and a second region 4B, the second region 4B includes the cells 4d, the surface roughness of the first region 4a is smaller than that of the second region 4B, light emitted from the LED chip is scattered by the cells of the second region, and the light emission is more uniform; the lower surface 420b2 of substrate includes third region 4c, the surface roughness of third region 4c is greater than the surface roughness of first region 4a, when the LED chip was placed first region 4a, because first region 4a is more level and smooth, therefore be favorable to subsequent fixed routing, when the LED chip was placed in second region 4b, when third region 4c, the contact area of solid crystal glue and substrate was big during the solid crystal, can increase the bonding strength of solid crystal glue and substrate, therefore, place the LED chip on upper surface 420b1, can guarantee the solid crystal routing and the bonding strength of solid crystal glue and substrate simultaneously. When the organic silicon modified polyimide resin composition is used as the LED soft filament substrate, light emitted by an LED chip is scattered through bubbles in the substrate, the light is emitted more uniformly, and the glare phenomenon can be further improved. In one embodiment, the surface of the base layer 420b may be treated with a silicone resin or titanate coupling agent, preferably a silicone resin containing methanol or titanate coupling agent containing methanol, or a silicone resin containing isopropyl alcohol, and the treated base layer has a cross-sectional view as shown in fig. 5C, the upper surface 420b1 of the base layer has a relatively uniform surface roughness, the lower surface 420b2 of the base layer includes a third region 4C and a fourth region 4e, and the surface roughness of the third region 4C is greater than that of the fourth region 4 e. The surface roughness of the upper surface 420b1 of the base layer may be equal to the surface roughness of the fourth region 4 e. The surface of the base layer 420b is treated to allow a highly reactive and strong substance to enter a part of the pores 4d, thereby enhancing the strength of the base layer.

When the organosilicon modified polyimide resin composition is prepared by a vacuum defoaming method, the vacuum degree during vacuum defoaming is-0.5 to-0.09 MPa, preferably-0.2 to-0.09 MPa.

According to the invention, the resin with excellent light transmittance, chemical resistance, heat discoloration resistance, thermal conductivity, film mechanical property and optical rotation resistance required by the LED soft filament substrate can be obtained. Further, the highly thermally conductive resin film can be formed by a simple coating method such as a printing method coating method, an ink-jet method, a dispensing method, or the like.

When organosilicon modified polyimide resin composition complex film was as filament substrate (or basic unit), the LED chip was six luminous bodies, and during the preparation of LED filament, at least biplanar of LED chip was wrapped up by the top layer, and current LED filament when lighting, can appear the inhomogeneous phenomenon of top layer and basic unit colour temperature, or granular sensation can appear in the basic unit, therefore the complex film as the filament substrate need possess excellent transparency.

Referring to fig. 6A and 6B, fig. 6A is a schematic view of an LED bulb lamp according to an embodiment of the invention, and fig. 6B is a front view (or a side view) of the LED bulb lamp of fig. 6A. As shown in fig. 6A and 6B, the LED bulb 20d includes a lamp housing 12, a base 16 connected to the lamp housing 12, at least two conductive brackets 51a and 51B disposed in the lamp housing 12, a cantilever 15, a stem 19, and a single LED filament 100. The stem 19 includes a stem bottom and a stem top, which are opposite to each other, the stem bottom is connected to the lamp head 16, and the stem top extends into the lamp housing 12 along an extending direction of the stem 19, for example, the stem top may be located at the center of the lamp housing 12. In this embodiment the stem 19 comprises a pole 19a, where the pole 19a is considered as an integral part of the stem 19, and thus the top end of the stem 19 is the top end of the pole 19 a.

Conductive brackets

51a, 51b connect the stems 19. The LED filament 100 includes a filament body and two electrodes 506, the two electrodes 506 are located at two opposite ends of the filament body, and the filament body is the other part of the LED filament 100 not including the electrodes 506. The two filament electrodes 506 are respectively connected with two

conductive supports

51a and 51b, and the filament body surrounds the stem 19. One end of the cantilever 15 is connected to the stem 19 and the other end is connected to the filament body.

Referring to fig. 6C, fig. 6C is a top view of the LED bulb 20d of fig. 6A. As shown in fig. 6C, the LED filament 100 body includes a primary light emitting surface Lm and a secondary light emitting surface Ls. Any section of the primary light emitting surface Lm faces the bulb 12 or the base 16 at any angle, i.e., faces the outside of the LED bulb 20d or faces the outside of the bulb 12, and any section of the secondary light emitting surface Ls faces the stem 19 or the top of the stem 19 at any angle, i.e., faces the inside of the LED bulb 20d or faces the center of the bulb 12. In other words, when a user views the LED bulb 20d from the outside, the main light emitting surface Lm of the LED filament 100 is seen at any angle. Based on this arrangement, the effect of illumination will be better.

The LED filaments 100 in the LED bulb (e.g., the LED bulb 20d) can be formed in different shapes or curves, and any of the LED filaments 100 can be configured to have symmetrical characteristics. The symmetrical characteristic is beneficial to generating uniform and widely distributed light rays, so that the LED bulb lamp can generate a full-cycle effect. The symmetry properties of the LED filament 100 are as follows.

The definition of the symmetrical characteristic of the LED filament 100 may be based on four quadrants as defined in a top view of the LED bulb. Four quadrants may be defined in a top view of the LED bulb, the origins of which may be defined as the centers of the stem or pole of the LED bulb in the top view (e.g., the top center of the pole of stem 19 of fig. 1A or the top center of pole 19a of fig. 6A). The LED filament of the LED bulb (e.g., fig. 1B) may exhibit an annular structure, shape, or contour in a top view. The LED filaments appearing in the four quadrants in the top view will have symmetry.

For example, when the LED filament is operated, the brightness of the LED filament in the first quadrant in the top view is symmetrical to the brightness of the LED filament in the second, third or fourth quadrant in the top view. In some embodiments, the structure of the portion of the LED filament in the first quadrant in the top view will be symmetrical to the structure of the portion of the LED filament in the second, third, or fourth quadrant in the top view. In addition, the light emitting direction of the part of the LED filament in the first quadrant in the top view is symmetrical to the light emitting direction of the part of the LED filament in the second quadrant, the third quadrant or the fourth quadrant in the top view.

In other embodiments, the arrangement of the LED chips in the portion of the LED filament in the first quadrant in the top view (e.g., the density variation of the LED chips in the portion of the LED filament in the first quadrant) may be symmetrical to the arrangement of the LED chips in the portion of the LED filament in the second, third, or fourth quadrant in the top view.

In other embodiments, the power arrangement of the LED chips with different powers of the LED filament in the portion of the first quadrant in the top view (e.g., the position distribution of the LED chips with different powers of the LED filament in the portion of the first quadrant) may be symmetrical to the power arrangement of the LED chips with different powers of the LED filament in the portion of the second quadrant, the third quadrant, or the fourth quadrant in the top view.

In other embodiments, when the LED filament is distinguishable as segments and the segments are defined by refractive indices that are distinguishable from one another, the refractive index of the segments of the LED filament in the first quadrant of the top view will be symmetric with respect to the refractive index of the segments of the LED filament in the second, third, or fourth quadrant of the top view.

In other embodiments, when the LED filament is distinguishable into segments and the segments are defined by surface roughness that is distinguishable from each other, the surface roughness of the segments of the LED filament in the first quadrant of the top view will be symmetrical to the surface roughness of the segments of the LED filament in the second, third or fourth quadrant of the top view.

The LED filaments present in the four quadrants of the top view may be point symmetric (e.g., symmetric according to the origin of the four quadrants) or line symmetric (e.g., symmetric according to one of the two axes of the four quadrants).

The symmetrical structure of the LED filament in the four quadrants of the top view may have an error of at most 20% -50%, for example, when the structure of the portion of the LED filament in the first quadrant is symmetrical to the structure of the portion of the LED filament in the second quadrant, the LED filament has a designated point on the portion of the first quadrant, and the LED filament has a symmetrical point symmetrical to the designated point on the portion of the second quadrant, the designated point has a first position, the symmetrical point has a second position, and the first position and the second position may be completely symmetrical or have an error of 20% -50%.

In addition, in a top view, when the LED filament is symmetrical in two quadrants, it can also be defined that the length of the part of the LED filament in one quadrant is substantially equal to the length of the part of the LED filament in the other quadrant. The lengths of the portions of the LED filament in the different quadrants may also have an error of 20% -50%. Wherein the length may be a length of the LED filament extending along an axial direction thereof.

The definition of the symmetrical characteristic of the LED filament 100 may be based on four quadrants defined by the LED bulb in side, front, or rear views. In the present embodiment, the side view of the LED bulb lamp includes a front view or a rear view. In a side view of an LED bulb (e.g., the LED bulb 20d of fig. 6A), four quadrants may be defined, in which case, an extension direction (from the lamp head 16 toward a top end of the lamp housing 12 away from the lamp head 16) of a stem or a rod (e.g., the rod 19a of the LED bulb 20d of fig. 6A) in the LED bulb may be defined as a Y-axis, and an X-axis may traverse a middle of the rod, where an origin of the four quadrants is defined as a middle of the rod, i.e., an intersection of the X-axis and the Y-axis. In various embodiments, the X-axis may traverse any point of the upright, for example, the X-axis may traverse a top end of the upright, a bottom end of the upright, or a point at a particular height of the upright (e.g., at 2/3).

In addition, the parts of the LED filament in the first quadrant and the second quadrant (upper quadrant) in the side view are symmetrical in brightness (for example, line symmetry is formed for the Y axis); the LED filaments, which are positioned in the third and fourth quadrants (lower quadrants) in the side view, are symmetrical in brightness (e.g., line-symmetrical about the Y-axis). However, the brightness exhibited by the portion of the LED filament in the upper quadrant in side view is not symmetrical to the brightness exhibited by the portion of the LED filament in the lower quadrant in side view.

In some embodiments, the portions of the LED filaments in the first quadrant and the second quadrant (i.e., the upper two quadrants) are structurally symmetrical (e.g., line symmetry with the Y-axis as the line of symmetry). The portions of the LED filaments in the third and fourth quadrants (i.e., the lower two quadrants) are also structurally symmetrical (e.g., line symmetry with the Y-axis as the symmetry line). In addition, the light emitting direction of the part of the LED filament in the first quadrant in the side view is symmetrical to the light emitting direction of the part of the LED filament in the second quadrant in the side view; the light emitting direction of the part of the LED filament in the third quadrant in the side view is symmetrical to the light emitting direction of the part of the LED filament in the fourth quadrant in the side view.

In other embodiments, the arrangement of the LED chips on the portion of the LED filament in the first quadrant in side view may be symmetrical to the arrangement of the LED chips on the portion of the LED filament in the second quadrant in side view; the arrangement of the LED chips on the portion of the LED filament in the third quadrant in the side view will be symmetrical to the arrangement of the LED chips on the portion of the LED filament in the fourth quadrant in the side view.

In other embodiments, the power arrangement of LED chips with different powers of the LED filament on the part of the first quadrant in side view will be symmetrical to the power arrangement of LED chips with different powers of the LED filament on the part of the second quadrant in side view; the power arrangement of the LED chips with different powers of the LED filament on the part of the third quadrant in the side view will be symmetrical to the power arrangement of the LED chips with different powers of the LED filament on the part of the fourth quadrant in the side view.

In other embodiments, when the LED filament is distinguishable into segments and the segments are defined by refractive indices that are distinguishable from one another, the refractive index of the segments of the LED filament in the first quadrant portion in side view will be symmetric to the refractive index of the segments of the LED filament in the second quadrant portion in side view; the refractive index of the plurality of segments of the LED filament in the third quadrant of the side view will be symmetrical to the refractive index of the plurality of segments of the LED filament in the fourth quadrant of the side view.

In other embodiments, when the LED filament is distinguishable into segments and the segments are defined by surface roughnesses that are distinguishable from one another, the surface roughness of the segments of the LED filament in side view on the portion of the first quadrant is symmetrical to the surface roughness of the segments of the LED filament in side view on the portion of the second quadrant; the surface roughness of the plurality of segments of the LED filament in the third quadrant of the side view is symmetrical to the surface roughness of the plurality of segments of the LED filament in the fourth quadrant of the side view.

In addition, in a side view, the portions of the LED filament appearing in the upper two quadrants and the portions of the LED filament appearing in the lower two quadrants are asymmetrical in brightness. In some embodiments, the portions of the LED filament present in the first quadrant and the fourth quadrant are asymmetric in structure, in length, in light exit direction, in configuration of the LED chips, in power arrangement of the LED chips with different power, in refractive index, or in surface roughness, while the portions of the LED filament present in the second quadrant and the third quadrant are asymmetric in structure, in length, in light exit direction, in configuration of the LED chips, in power arrangement of the LED chips with different power, in refractive index, or in surface roughness. To meet the lighting objectives and requirements of a full-perimeter light fixture, more light should be emitted from the upper quadrant (the portion away from the base 16) than from the lower quadrant (the portion closer to the base 16) in side view. Therefore, the asymmetric characteristic between the upper quadrant and the lower quadrant of the LED filament of the LED bulb lamp can help to meet the requirement of full-cycle light by concentrating light rays in the upper quadrant.

The symmetrical configuration of the LED filament in the first and second quadrants of the side view may have an error (tolerance) of 20% -50%, for example, the LED filament has a designated point on the portion of the first quadrant and the LED filament has a symmetrical point symmetrical to the designated point on the portion of the second quadrant, the designated point has a first position, the symmetrical point has a second position, the first and second positions may be completely symmetrical or have an error of 20% -50%. The meaning of the error herein can be referred to the above description.

Further, in a side view, the length of the portion of the LED filament in the first quadrant may be substantially equal to the length of the portion of the LED filament in the second quadrant. In a side view, the length of the portion of the LED filament in the third quadrant will be substantially equal to the length of the portion of the LED filament in the fourth quadrant. However, in a side view, the length of the portion of the LED filament in the first quadrant or the second quadrant may be different from the length of the portion of the LED filament in the third quadrant or the fourth quadrant. In some embodiments, in a side view, the length of the portion of the LED filament in the third quadrant or the fourth quadrant may be less than the length of the portion of the LED filament in the first quadrant or the second quadrant. In a side view, the length of the portion of the LED filament in the first quadrant or the second quadrant or the length of the portion of the LED filament in the third quadrant or the fourth quadrant may also have an error of 20% -50%.

Referring to fig. 6D, fig. 6D shows the LED filament 100 of fig. 6B in a two-dimensional coordinate system defining four quadrants. The LED filament 100 of fig. 6D is identical to the LED filament 100 of fig. 6B, and fig. 6D is a front view (or side view) of the LED bulb 20D of fig. 6A. As shown in fig. 6B and 6D, the Y-axis is aligned with the leg 19a of the stem (i.e., the Y-axis is located in the extending direction of the leg 19a), and the X-axis crosses the leg 19a (i.e., the X-axis is perpendicular to the extending direction of the leg 19 a). As shown in fig. 6D, the LED filament 100 is divided into a first portion 100p1, a second portion 100p2, a third portion 100p3 and a fourth portion 100p4 by the X axis and the Y axis in a side view. The first portion 100p1 of the LED filament 100 is a portion appearing in a first quadrant in a side view, the second portion 100p2 of the LED filament 100 is a portion appearing in a second quadrant in a side view, the third portion 100p3 of the LED filament 100 is a portion appearing in a third quadrant in a side view, and the fourth portion 100p4 of the LED filament 100 is a portion appearing in a fourth quadrant in a side view.

As shown in fig. 6D, the LED filament 100 is line symmetric. The LED filament 100 is symmetrical with respect to the Y axis in a side view, that is, the geometries of the first portion 100p1 and the fourth portion 100p4 are symmetrical to the geometries of the second portion 100p2 and the third portion 100p 3. Specifically, the first portion 100p1 is symmetrical to the second portion 100p2 in side view, and further, the first portion 100p1 and the second portion 100p2 are symmetrical in structure with respect to the Y-axis in side view. In addition, the third portion 100p3 is symmetrical to the fourth portion 100p4 in side view, and further, the third portion 100p3 and the fourth portion 100p4 are symmetrical in structure with respect to the Y axis in side view.

In the present embodiment, as shown in fig. 6D, the first portion 100p1 and the second portion 100p2 located in the upper quadrant (i.e., the first quadrant and the second quadrant) in the side view and the third portion 100p3 and the fourth portion 100p4 located in the lower quadrant (i.e., the third quadrant and the fourth quadrant) in the side view are asymmetric. Specifically, the first portion 100p1 and the fourth portion 100p4 are asymmetrical in side view, and the second portion 100p2 and the third portion 100p3 are asymmetrical in side view. According to the asymmetric characteristic of the structure of the LED filament 100 in the upper quadrant and the lower quadrant in fig. 6D, the light emitted from the upper quadrant and passing through the upper lamp housing 12 (the portion far from the lamp cap 16) is more than the light emitted from the lower quadrant and passing through the lower lamp housing 12 (the portion near the lamp cap 16), so as to meet the illumination purpose and requirement of the full-circle light fixture.

Based on the symmetrical characteristic of the LED filament 100, the structure of the two symmetrical portions of the LED filament 100 in the side view (the first portion 100p1 and the second portion 100p2 or the third portion 100p3 and the fourth portion 100p4) may be completely symmetrical or symmetrical with errors in structure. The error (tolerance) between the structures of the two symmetrical portions of the LED filament 100 in the side view may be 20% -50% or less.

The error may be defined as a difference in coordinates (i.e., an x-coordinate and a Y-coordinate), for example, if the LED filament 100 has a designated point on the first portion 100p1 of the first quadrant and the LED filament 100 has a symmetrical point symmetrical to the designated point with respect to the Y-axis on the second portion 100p2 of the second quadrant, the absolute value of the Y-coordinate or the x-coordinate of the designated point may be equal to the absolute value of the Y-coordinate or the x-coordinate of the symmetrical point, or may have a difference of 20% with respect to the absolute value of the Y-coordinate or the x-coordinate of the symmetrical point.

For example, as shown in fig. 6D, one designated point (x1, Y1) of the LED filament 100 in the first portion 100p1 of the first quadrant is defined as a first position, one symmetric point (x2, Y2) of the LED filament 100 in the second portion 100p2 of the second quadrant is defined as a second position, and the second position of the symmetric point (x2, Y2) is symmetric to the first position of the designated point (x1, Y1) with respect to the Y axis. The first and second positions may be completely symmetrical or symmetrical with a 20% -50% error. In the present embodiment, the first portion 100p1 and the second portion 100p2 are completely symmetrical in structure, that is, x2 of the symmetrical points (x2, y2) is equal to negative x1 of the designated points (x1, y1), and y2 of the symmetrical points (x2, y2) is equal to y1 of the designated points (x1, y 1).

For example, as shown in fig. 6D, one designated point (x3, Y3) of the LED filament 100 in the third portion 100p3 of the third quadrant is defined as a third position, one symmetric point (x4, Y4) of the LED filament 100 in the fourth portion 100p4 of the fourth quadrant is defined as a fourth position, and the fourth position of the symmetric point (x4, Y4) is symmetric with respect to the Y axis to the third position of the designated point (x3, Y3). The third and fourth positions may be completely symmetrical or symmetrical with a 20% -50% error. In the present embodiment, the third portion 100p3 and the fourth portion 100p4 are symmetrical with respect to the structural error (for example, there may be an error smaller than 20% in coordinates), that is, the absolute value of x4 of the symmetrical point (x4, y4) is not equal to the absolute value of x3 of the designated point (x3, y3), and the absolute value of y4 of the symmetrical point (x4, y4) is not equal to the absolute value of y3 of the designated point (x3, y 3). As shown in fig. 6D, the vertical height of the designated point (x3, Y3) is slightly lower than the vertical height of the symmetry point (x4, Y4), and the designated point (x3, Y3) is closer to the Y-axis than the symmetry point (x4, Y4). Accordingly, the absolute value of y4 is slightly less than the absolute value of y3, while the absolute value of x4 is slightly greater than the absolute value of x 3.

As shown in fig. 6D, the length of the first portion 100p1 of the first quadrant of the LED filament 100 in side view is substantially equal to the length of the second portion 100p2 of the second quadrant of the LED filament 100 in side view. In this embodiment, the length is defined along the elongation of the LED filament 100 in a plan view (e.g., a side, front, or top view). For example, the first portion 100p1 is elongated in the first quadrant of the side view of fig. 6D to form an inverted "V" shape having two ends contacting the X-axis and the Y-axis, respectively, and the length of the first portion 100p1 is defined along the inverted "V" shape between the X-axis and the Y-axis.

Furthermore, the length of the third portion 100p3 of the third quadrant of the LED filament 100 in side view is substantially equal to the length of the fourth portion 100p4 of the fourth quadrant of the LED filament 100 in side view. Since the third portion 100p3 and the fourth portion 100p4 are in error-symmetrical with each other in structure with respect to the Y-axis, the length of the third portion 100p3 is slightly different from the length of the fourth portion 100p 4. This error may be 20% -50% or less.

As shown in fig. 6D, in the side view, the light exit direction of a specified point of the first portion 100p1 and the light exit direction of a point of symmetry of the second portion 100p2 are symmetrical in direction with respect to the Y axis. In this embodiment, the light emitting direction may be defined as a direction in which the LED chip faces. And the direction in which the LED chips face is defined as the direction in which the main light emitting surface Lm faces, the light outgoing direction can also be defined as the normal direction of the main light emitting surface Lm. For example, the light exit direction ED of a specified point (x1, y1) of the first portion 100p1 is upward in fig. 6D, and the light exit direction ED of a symmetrical point (x2, y2) of the second portion 100p2 is upward in fig. 6D. The light exit direction ED of the designated point (x1, Y1) and the light exit direction ED of the point of symmetry (x2, Y2) are symmetrical with respect to the Y axis. Further, the light outgoing direction ED of a specified point (x3, y3) of the third portion 100p3 is a lower left direction in fig. 6D, and the light outgoing direction ED of a symmetrical point (x4, y4) of the fourth portion 100p4 is a lower right direction in fig. 6D. The light exit direction ED of the designated point (x3, Y3) and the light exit direction ED of the point of symmetry (x4, Y4) are symmetrical with respect to the Y axis.

Referring to fig. 6E, fig. 6E shows the LED filament 100 of fig. 6C in a two-dimensional coordinate system defining four quadrants. The LED filament 100 of fig. 6E is identical to the LED filament 100 of fig. 6C, and fig. 6E is a top view of the LED bulb 20d of fig. 6A. As shown in fig. 6C and 6E, the origin of the four quadrants is defined as the center of the stem 19a of the LED bulb 20d in a top view (e.g., the top center of the stem 19a of fig. 6A). In this embodiment, the Y-axis is vertical in fig. 6E, and the X-axis is horizontal in fig. 6E. As shown in fig. 6E, the LED filament 100 is divided into a first portion 100p1, a second portion 100p2, a third portion 100p3 and a fourth portion 100p4 by the X axis and the Y axis in a top view. The first portion 100p1 of the LED filament 100 is a portion appearing in a first quadrant in a top view, the second portion 100p2 of the LED filament 100 is a portion appearing in a second quadrant in a top view, the third portion 100p3 of the LED filament 100 is a portion appearing in a third quadrant in a top view, and the fourth portion 100p4 of the LED filament 100 is a portion appearing in a fourth quadrant in a top view.

In some embodiments, the LED filament 100 in a top view may be point symmetric (e.g., symmetric according to the origin of the four quadrants) or line symmetric (e.g., symmetric according to one of the two axes of the four quadrants). In the present embodiment, as shown in fig. 6E, the LED filament 100 is line-symmetric in the top view, and particularly, the LED filament 100 is symmetric with respect to the Y axis in the top view, that is, the geometries of the first portion 100p1 and the fourth portion 100p42 are symmetric with respect to the geometries of the second portion 100p2 and the third portion 100p 3. Specifically, the first portion 100p1 is symmetrical to the second portion 100p2 in top view, and further, the first portion 100p1 and the second portion 100p2 are symmetrical in structure with respect to the Y-axis in top view. In addition, the third portion 100p3 is symmetrical to the fourth portion 100p4 in top view, and further, the third portion 100p3 and the fourth portion 100p4 are symmetrical in structure with respect to the Y axis in top view.

Based on the symmetrical characteristic of the LED filament 100, the structure of the two symmetrical portions of the LED filament 100 (the first portion 100p1 and the second portion 100p2 or the third portion 100p3 and the fourth portion 100p4) in the top view may be completely symmetrical or symmetrical with errors in structure. The error (tolerance) between the structures of the two symmetrical portions of the LED filament 100 in the top view may be 20% -50% or less.

For example, as shown in fig. 6E, one designated point (x1, Y1) of the LED filament 100 in the first portion 100p1 of the first quadrant is defined as a first position, one symmetric point (x2, Y2) of the LED filament 100 in the second portion 100p2 of the second quadrant is defined as a second position, and the second position of the symmetric point (x2, Y2) is symmetric to the first position of the designated point (x1, Y1) with respect to the Y axis. The first and second positions may be completely symmetrical or symmetrical with a 20% -50% error. In the present embodiment, the first portion 100p1 and the second portion 100p2 are completely symmetrical in structure, that is, x2 of the symmetrical points (x2, y2) is equal to negative x1 of the designated points (x1, y1), and y2 of the symmetrical points (x2, y2) is equal to y1 of the designated points (x1, y 1).

For example, as shown in fig. 6E, one designated point (x3, Y3) of the LED filament 100 in the third portion 100p3 of the third quadrant is defined as a third position, one symmetric point (x4, Y4) of the LED filament 100 in the fourth portion 100p4 of the fourth quadrant is defined as a fourth position, and the fourth position of the symmetric point (x4, Y4) is symmetric with respect to the Y axis to the third position of the designated point (x3, Y3). The third and fourth positions may be completely symmetrical or symmetrical with a 20% -50% error. In the present embodiment, the third portion 100p3 and the fourth portion 100p4 are symmetrical with errors in structure (for example, there may be an error less than 20% in coordinates), that is, x4 of the symmetrical point (x4, y4) is not equal to the negative value of x3 of the designated point (x3, y3), and y4 of the symmetrical point (x4, y4) is not equal to y3 of the designated point (x3, y 3). As shown in fig. 6E, the vertical height of the designated point (x3, Y3) is slightly lower than the vertical height of the symmetry point (x4, Y4), and the designated point (x3, Y3) is closer to the Y-axis than the symmetry point (x4, Y4). Accordingly, the absolute value of y4 is slightly less than the absolute value of y3, while the absolute value of x4 is slightly greater than the absolute value of x 3.

As shown in fig. 6E, the length of the first portion 100p1 of the first quadrant of the LED filament 100 in the top view is substantially equal to the length of the second portion 100p2 of the second quadrant of the LED filament 100 in the top view. In this embodiment, the length is defined along the elongation of the LED filament 100 in a plan view (e.g., top, front, or side view). For example, second portion 100p2 is elongated in the second quadrant of the top view of FIG. 6E to form an inverted "L" shape having two ends that contact the X-axis and Y-axis, respectively, and the length of second portion 100p2 is defined along the inverted "L" shape.

Furthermore, the length of the third portion 100p3 of the third quadrant of the LED filament 100 in top view is substantially equal to the length of the fourth portion 100p4 of the fourth quadrant of the LED filament 100 in top view. Since the third portion 100p3 and the fourth portion 100p4 are in error-symmetrical with each other in structure with respect to the Y-axis, the length of the third portion 100p3 is slightly different from the length of the fourth portion 100p 4. This error may be 20% -50% or less.

As shown in fig. 6E, in a top view, the light exit direction of a specified point of the first portion 100p1 and the light exit direction of a point of symmetry of the second portion 100p2 are symmetrical in direction with respect to the Y-axis. In this embodiment, the light emitting direction may be defined as a direction in which the LED chip faces. And the direction in which the LED chips face is defined as the direction in which the main light emitting surface Lm faces, the light outgoing direction can also be defined as the normal direction of the main light emitting surface Lm. For example, the light exit direction ED of a specified point (x1, y1) of the first portion 100p1 is rightward in fig. 6E, and the light exit direction ED of a symmetrical point (x2, y2) of the second portion 100p2 is leftward in fig. 6E. The light exit direction ED of the designated point (x1, Y1) and the light exit direction ED of the point of symmetry (x2, Y2) are symmetrical with respect to the Y axis. Further, the light outgoing direction ED of a specified point (x3, y3) of the third portion 100p3 is a lower left direction in fig. 6E, and the light outgoing direction ED of a symmetrical point (x4, y4) of the fourth portion 100p4 is a lower right direction in fig. 6E. The light exit direction ED of the designated point (x3, Y3) and the light exit direction ED of the point of symmetry (x4, Y4) are symmetrical with respect to the Y axis. In addition, in a top view, the light-emitting direction ED of any given point on the first portion 100p1 and the light-emitting direction ED of any corresponding symmetric point on the second portion 100p2, which is symmetric to the given point, are directionally symmetric with respect to the Y-axis. In a top view, the light-emitting direction ED of any given point on the third portion 100p3 and the light-emitting direction ED of any corresponding symmetric point on the fourth portion 100p4, which is symmetric to the given point, are symmetric in direction with respect to the Y-axis.

As described in the foregoing embodiments, in the side view (including the front view or the rear view) and/or the top view, the symmetrical characteristics of the LED filament 100 with respect to the symmetrical structure, the symmetrical light emitting direction, the symmetrical configuration of the LED chips 442, the symmetrical power arrangement of the LED chips 442, the symmetrical refractive index and/or the symmetrical surface roughness are helpful for generating uniformly distributed light, and the symmetrical design of the symmetrical power arrangement, the symmetrical refractive index and/or the symmetrical surface roughness of the LED chips 442 can be comprehensively considered by matching with the sectional characteristics of the LED filament, so that the LED bulb lamp with the LED filament 100 can generate full ambient light.

The definition of the full-cycle light depends on the area where the LED bulb lamp is used, and can change along with the time. According to different organizations and countries, the LED bulb lamp capable of providing full-cycle light is declared to be capable of meeting different standards. The american energy star project lamp qualification criteria, first edition (bulb) 24, defines eligibility criterion version1.0, which requires that the emitted light between 135 and 180 degrees should be at least 5% of the total luminous flux (lm) at a full perimeter lamp base up setting, while 90% of the luminance measurements are variable, but not more than 25% different from the average of the total luminance measurements over all planes. Luminance (cd) is measured in each vertical plane at a vertical angle of 5 degrees increase (maximum) between 0 and 135 degrees. In JEL801 specifications of japan, the LED lamp is required to have a luminous flux within 120 degrees of the optical axis, which is not less than 70% of the total luminous flux of the bulb lamp. Based on the arrangement of the LED filaments with the symmetrical characteristic in the embodiment, the LED bulb lamp with the LED filaments can meet different standards of a full-cycle light lamp.

The term "one LED filament" and "one LED filament" as used herein refers to a single LED filament structure which is formed by connecting the aforementioned conductor segments and LED segments together, has the same and continuous light conversion layer (including the same and continuously formed top layer or bottom layer), and has two conductive electrodes electrically connected to the bulb conductive support only at two ends.

In some embodiments, the LED filament 100 may have multiple LED segments, the LED chips in the same LED segment are connected in series, and the different LED segments are connected in parallel, wherein the anode of each LED segment may be used as the anode of the LED filament, and the cathode of each LED segment may be used as the cathode of the LED filament, and is respectively connected to two or more conductive brackets (e.g., 51A and 51b in fig. 1A), and is electrically connected to the power module (e.g., 518 in fig. 1A) through the conductive brackets. As shown in fig. 7A, fig. 7A is a schematic diagram of an LED filament circuit according to an embodiment of the present invention, in which the LED filament 100 has two LED

segments

402 and 404, each LED segment 402/404 may include one or more LED chips, the LED chips in the same LED segment 402/404 are connected in series, and the

LED segments

402 and 404 have independent current paths (i.e., are connected in a shunt manner) after being electrically connected to each other. More specifically, the anodes of the

LED segments

402 and 404 of the present embodiment are connected together and serve as the anode P1 of the LED filament 100, the cathode of the LED segment 402 serves as the first cathode N1 of the LED filament 100, and the cathode of the LED segment 402 serves as the second cathode N2 of the LED filament 100. The anode P1, the first cathode N1 and the second cathode N2 of the LED filament 100 are electrically connected to a power module, such as the

conductive brackets

51a and 51b shown in fig. 6A, through conductive brackets, respectively.

More specifically, the electrical connection relationship between the positive electrode P1, the first negative electrode N1, and the second negative electrode N2 of the LED filament 100 and the power module can be as shown in fig. 7B or fig. 7C, wherein fig. 7B and fig. 7C are schematic diagrams of the electrical connection relationship of the LED filament according to different embodiments of the present invention. Referring to fig. 7B, in the present embodiment, the anode P1 of the LED filament 100 is electrically connected to the first output terminal (or called positive output terminal) of the power module 518, and the first cathode N1 and the second cathode N2 of the LED filament 100 are electrically connected/short-circuited together and are commonly electrically connected to the second output terminal (or called negative output terminal) of the power module 518. In conjunction with fig. 7A, under the electrical connection relationship of fig. 7B, the

LED segments

402 and 404 can be regarded as being connected in parallel to the output terminal of the power module 518, and thus both the

LED segments

402 and 404 are driven by the driving voltage V1 between the first output terminal and the second output terminal. Under the condition that the number and configuration of the chips included in the

LED segments

402 and 404 are the same or similar, the driving current provided by the power module 518 is uniformly distributed to each of the

LED segments

402 and 404, so that the

LED segments

402 and 404 exhibit substantially uniform brightness and/or color temperature.

Referring to fig. 7C, in the present embodiment, the anode P1 of the LED filament 100 is electrically connected to the first output terminal (or called positive output terminal) of the power module 518, the first cathode N1 of the LED filament 100 is electrically connected to the second output terminal (or called first negative output terminal) of the power module 518, and the second cathode N1 of the LED filament 100 is electrically connected to the third output terminal (or called second negative output terminal) of the power module 518, wherein a driving voltage V1 output is formed between the first output terminal and the second output terminal of the power module 518, and another driving voltage V2 output is formed between the first output terminal and the third output terminal of the power module 518. In the electrical connection relationship of fig. 7C, as seen in fig. 7A, the LED segment 402 is electrically connected between the first output terminal and the second output terminal, and the LED segment 404 is electrically connected between the first output terminal and the third output terminal, so that the

LED segments

402 and 404 are considered to be driven by the driving voltages V1 and V2, respectively. With this configuration, the driving current provided by the power module 518 to the LED segment 402/404 can be independently controlled by modulating the output driving voltages V1 and V2, so that the

LED segments

402 and 404 can have corresponding brightness and/or color temperature, respectively. In other words, under the configuration of fig. 7C, the power supply module 518 can be designed and controlled to implement the step dimming function on a single LED filament.

In some embodiments, the second output terminal and the third output terminal of the power module 518 may be connected together through a resistor, and one of the second output terminal and the third output terminal is electrically connected/shorted to a ground terminal. By this configuration, the negative output terminals with different levels can be formed, thereby generating the driving voltages V1 and V2 with different levels. In some embodiments, the second output terminal and the third output terminal may also have their levels controlled by circuits, respectively, and the present invention is not limited to the above embodiments.

The features of the various embodiments of the invention described above may be combined and changed arbitrarily without being mutually exclusive and are not limited to a specific embodiment. Such as those described in the embodiment of fig. a, although features not described in the embodiment of fig. C may also be included in the embodiment of fig. a, it will be apparent to those of ordinary skill in the art that such features may be applied to fig. C without inventive faculty based on the description of fig. a; for another example, although the invention has been described with reference to an LED bulb lamp as an example, it is obvious that these designs can be applied to lamps of other shapes or types without creativity, such as LED candle lamps, etc., which are not listed here.

While the invention has been described in terms of preferred embodiments, it will be understood by those skilled in the art that the examples are intended in a descriptive sense only and not for purposes of limitation. It should be noted that equivalent variations and substitutions to those of the embodiments are intended to be included within the scope of the present invention. Therefore, the protection scope of the present invention is subject to the scope defined by the appended claims.

Claims

1. An LED bulb lamp, characterized by comprising:

a lamp housing;

the lamp holder is connected with the lamp shell to form an accommodating space, and the lamp holder comprises a driving circuit;

the conductive brackets are electrically connected with the driving circuit of the lamp holder and are arranged in the accommodating space; and

the LED light source comprises a light emitting part, a light emitting part and a light emitting part, wherein the light emitting part is in a single bent strip shape and comprises a light conversion coating, a plurality of LED chip units, conductor sections and at least two electrodes which are respectively connected with the conductive support, each LED chip unit comprises at least two LED chips which are connected through a lead, the LED chip units are electrically connected in the light emitting part through the conductor sections, the conductor sections comprise conductors, the conductors are metal wires, and the lengths of the metal wires in the length extending direction of the light emitting part are larger than the leads;

wherein a portion of each of the electrodes is exposed outside of the light conversion coating;

the electrode is connected with the LED chip unit through a first lead, and the conductor section is connected with the LED chip unit through a second lead;

the light conversion coating comprises a first light conversion layer and a base layer, wherein the upper surface of the base layer is pasted with a plurality of conductor segments and the LED chip units, the first light conversion layer covers two ends of the conductor segments and exposes one part of the conductor segments, and the materials of the first light conversion layer on the LED segments and the conductor segments are different;

the LED chip in each LED chip unit is connected in series, the anode of each LED chip unit is connected together to serve as the anode of the light-emitting part, the cathode of one LED chip unit serves as the first cathode of the light-emitting part, the cathode of the other LED chip unit serves as the second cathode of the light-emitting part, and the anode, the first cathode and the second cathode of the light-emitting part are electrically connected to the driving circuit through the conductive support respectively.

2. The LED bulb lamp according to claim 1, wherein the conductor segment is a copper foil, the conductor segment has an area covered by the first light conversion layer at both ends thereof, an average thickness thereof is equal to or different from each other, and an area covered by the first light conversion layer at the upper surface thereof is 30-40%.

3. The LED bulb according to claim 2, wherein the conductor segment comprises a wavy concave structure, and the wavy concave structure is disposed on a surface edge of the conductor segment and surrounds the conductor segment with an axial direction of the LED light-emitting portion as a center.

4. The LED bulb as claimed in claim 2, wherein the conductor segment includes a wavy convex structure, the wavy convex structure is disposed on a surface edge of the conductor segment and surrounds the conductor segment with an axial direction of the LED light-emitting portion as a center.

5. The LED bulb lamp according to claim 2, wherein a lower surface of the base layer is further covered with a second light conversion layer having a uniform thickness, the upper surface and the lower surface of the base layer are opposite, and the second light conversion layer has an inclined side or an inclined side with an arc shape.

6. The LED bulb lamp according to claim 2, wherein the first light-converting layers cover the first and second wires to which the single LED chip unit is connected, and the number of the first light-converting layers is the same as the number of the LED chip units.

7. The LED bulb lamp according to claim 5, wherein the first and second light conversion layers comprise light-diffusing particles and light-guiding particles, the light-diffusing particles are phosphor, and the light-guiding particles are polymethyl methacrylate (PMMA) or resin.

8. The LED bulb lamp according to claim 2, wherein the base layer is formed by coating and drying an organosilicon modified polyimide resin composition, the composition comprising an organosilicon modified polyimide containing a repeating unit represented by the following general formula (I), and a heat curing agent, a phosphor, and heat dissipating particles, the heat curing agent being an epoxy resin, an isocyanate, or a bisoxazoline compound;

in the general formula (I), Ar¹Is a 4-valent organic group having a benzene ring or alicyclic hydrocarbon structure, Ar²Is a 2-valent organic group, R is independently selected from methyl or phenyl, and n is 1-5.

9. The LED bulb lamp according to claim 8, wherein Ar is¹Is a 4-valent organic group with a benzene ring structure or an alicyclic hydrocarbon structure containing active hydrogen functional groups, wherein the active hydrogen functional groups are any one of hydroxyl, amino, carboxyl or thiol, and Ar is²The functional group is a 2-valent organic group containing active hydrogen, and the active hydrogen functional group is any one of hydroxyl, amino, carboxyl or thiol.

10. The LED bulb lamp of claim 8, wherein the driving circuit comprises a power module, the anode of the light-emitting portion is electrically connected to a first output terminal of the power module, the first and second cathodes of the light-emitting portion are electrically connected and commonly connected to a second output terminal of the power module, and wherein the first output terminal is different from the second output terminal.