CN114552840A - Insulating sheet, method for producing same, and rotating electrical machine - Google Patents

Insulating sheet, method for producing same, and rotating electrical machine Download PDF

Info

Publication number
CN114552840A
CN114552840A CN202111374190.XA CN202111374190A CN114552840A CN 114552840 A CN114552840 A CN 114552840A CN 202111374190 A CN202111374190 A CN 202111374190A CN 114552840 A CN114552840 A CN 114552840A
Authority
CN
China
Prior art keywords
insulating
thermosetting resin
sheet
resin layer
mass
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202111374190.XA
Other languages
Chinese (zh)
Inventor
保田直纪
名取诗织
长谷川和哉
江头康平
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Publication of CN114552840A publication Critical patent/CN114552840A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K3/00—Details of windings
    • H02K3/32—Windings characterised by the shape, form or construction of the insulation
    • H02K3/34—Windings characterised by the shape, form or construction of the insulation between conductors or between conductor and core, e.g. slot insulation
    • H02K3/345—Windings characterised by the shape, form or construction of the insulation between conductors or between conductor and core, e.g. slot insulation between conductor and core, e.g. slot insulation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B29/00—Layered products comprising a layer of paper or cardboard
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B29/00—Layered products comprising a layer of paper or cardboard
    • B32B29/002—Layered products comprising a layer of paper or cardboard as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B29/005—Layered products comprising a layer of paper or cardboard as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to another layer of paper or cardboard layer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B3/00—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form
    • B32B3/26—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids ; characterised by an apertured layer
    • B32B3/266—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids ; characterised by an apertured layer characterised by an apertured layer, the apertures going through the whole thickness of the layer, e.g. expanded metal, perforated layer, slit layer regular cells B32B3/12
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B33/00—Layered products characterised by particular properties or particular surface features, e.g. particular surface coatings; Layered products designed for particular purposes not covered by another single class
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B32B37/12—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by using adhesives
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/02—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by structural features of a fibrous or filamentary layer
    • B32B5/022—Non-woven fabric
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/02—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by structural features of a fibrous or filamentary layer
    • B32B5/028—Net structure, e.g. spaced apart filaments bonded at the crossing points
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/22—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed
    • B32B5/24—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer
    • B32B5/26—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer another layer next to it also being fibrous or filamentary
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/04—Interconnection of layers
    • B32B7/12—Interconnection of layers using interposed adhesives or interposed materials with bonding properties
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
    • C08J7/04—Coating
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D163/00—Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D163/00—Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins
    • C09D163/10—Epoxy resins modified by unsaturated compounds
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D167/00—Coating compositions based on polyesters obtained by reactions forming a carboxylic ester link in the main chain; Coating compositions based on derivatives of such polymers
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D171/00—Coating compositions based on polyethers obtained by reactions forming an ether link in the main chain; Coating compositions based on derivatives of such polymers
    • C09D171/08—Polyethers derived from hydroxy compounds or from their metallic derivatives
    • C09D171/10—Polyethers derived from hydroxy compounds or from their metallic derivatives from phenols
    • C09D171/12—Polyphenylene oxides
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
    • C09D7/40—Additives
    • C09D7/60—Additives non-macromolecular
    • C09D7/61—Additives non-macromolecular inorganic
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B17/00—Insulators or insulating bodies characterised by their form
    • H01B17/56—Insulating bodies
    • H01B17/60—Composite insulating bodies
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B19/00—Apparatus or processes specially adapted for manufacturing insulators or insulating bodies
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K3/00—Details of windings
    • H02K3/30—Windings characterised by the insulating material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B32B37/14—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers
    • B32B37/24—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers with at least one layer not being coherent before laminating, e.g. made up from granular material sprinkled onto a substrate
    • B32B2037/243—Coating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2255/00—Coating on the layer surface
    • B32B2255/02—Coating on the layer surface on fibrous or filamentary layer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2255/00—Coating on the layer surface
    • B32B2255/12—Coating on the layer surface on paper layer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2255/00—Coating on the layer surface
    • B32B2255/26—Polymeric coating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00—Properties of the layers or laminate
    • B32B2307/20—Properties of the layers or laminate having particular electrical or magnetic properties, e.g. piezoelectric
    • B32B2307/206—Insulating
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2367/00—Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
    • C08J2367/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2463/00—Characterised by the use of epoxy resins; Derivatives of epoxy resins
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2463/00—Characterised by the use of epoxy resins; Derivatives of epoxy resins
    • C08J2463/10—Epoxy resins modified by unsaturated compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2467/00—Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2471/00—Characterised by the use of polyethers obtained by reactions forming an ether link in the main chain; Derivatives of such polymers
    • C08J2471/08—Polyethers derived from hydroxy compounds or from their metallic derivatives
    • C08J2471/10—Polyethers derived from hydroxy compounds or from their metallic derivatives from phenols
    • C08J2471/12—Polyphenylene oxides
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/64—Electric machine technologies in electromobility

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Wood Science & Technology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Power Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Textile Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Laminated Bodies (AREA)
  • Insulation, Fastening Of Motor, Generator Windings (AREA)
  • Organic Insulating Materials (AREA)
  • Insulating Bodies (AREA)

Abstract

An insulating sheet, a method of manufacturing the same, and a rotating electrical machine. The insulating sheet of the present invention comprises a sheet-like base material having pores, voids or meshes, and an insulating resin layer composed of a thermosetting resin composition provided on one or both surfaces of the base material; the base material is formed by a laminated sheet formed by laminating any one single-layer sheet or a plurality of sheets in insulating paper, an insulating film, non-woven fabrics and gridding cloth; the insulating resin layer is in an uncured or semi-cured state; the thermosetting resin composition has a first thermosetting resin which is solid at 25 ℃, a second thermosetting resin which is liquid at 25 ℃, and a latent curing agent which is reactive inert at 60 ℃ or lower; the mass part of the first thermosetting resin is in the range of 10 to 90 mass parts, assuming that the total mass of the first thermosetting resin and the second thermosetting resin is 100 mass parts.

Description

Insulating sheet, method for producing same, and rotating electrical machine
Technical Field
The invention relates to an insulating sheet, a method of manufacturing the same, and a rotating electrical machine.
Background
A rotating electric machine including a motor, a generator, a compressor, and the like includes a rotor and a stator, and the stator includes a stator core and a stator coil. In rotating electric machines, downsizing and high output power are being carried out. A rotating electrical machine includes an insulating member inside, and with the miniaturization and high output of the rotating electrical machine, an insulating material used for the insulating member is required to have excellent insulation properties, heat resistance, and heat dissipation properties. When an insulating member is disposed between members to be insulated of a rotating electrical machine, for example, in a gap between a stator core and a stator coil, if an air layer partially remains in the gap, the insulating property, heat radiation property, and vibration resistance are reduced. Conventionally, when a stator coil is housed in a slot of a stator core, an insulating paper is inserted into a gap between an inner wall of the slot and the stator coil, and the stator coil is impregnated with a liquid insulating varnish.
However, as the volume occupancy of the stator coil increases, the respective gaps of the slot inner wall, the stator coil, and the insulating paper, and the gap in the stator coil become narrow. Therefore, there is a problem that the insulating varnish does not sufficiently permeate the stator coil and is partially fixed. Further, if a low-viscosity varnish is used as the insulating varnish to improve permeability, most of the varnish dropped onto the coil end leaks out to the end face of the core portion, and therefore, there is a problem that the amount of adhesion inside the stator coil is insufficient. As a result, if the stator coil fixing performance is lowered, the long-term insulation reliability of the rotating electrical machine is adversely affected. In particular, in the case of a rotating electric machine for an automobile, a reduction in the fixing performance of a stator coil is a factor that deteriorates Noise, Vibration, and Harshness (NVH characteristics, hereinafter) which are one of the criteria for evaluating the comfort of the automobile.
Further, since the heat generation temperature of the stationary coil tends to increase with an increase in output power, it is necessary to improve the heat radiation performance of the stator coil in view of durability of the rotating electric machine. However, if the insulating varnish is not sufficiently attached to the stator coil and an air layer is included between the stator coil and the stator core, there is a problem that heat of the stator coil cannot be efficiently dissipated to the stator core.
In order to solve the problems caused by the insulating varnish, a method of fixing the stator coil and the stator core in an insulated manner without performing an insulating varnish impregnation treatment on the stator coil is disclosed (for example, see patent document 1). Since the insulating sheet in which the thermosetting resin in a semi-cured state is laminated on both surfaces of the insulating film base is disposed between members to be insulated of the rotating electrical machine, the insulating fixing resin obtained by curing the thermosetting resin in a semi-cured state can be filled between the insulating film base and the stator coil and between the insulating film base and the inner wall of the groove.
Documents of the prior art
Patent document
Patent document 1 Japanese patent laid-open No. 2009-33889
Disclosure of Invention
Technical problem to be solved by the invention
The above-mentioned patent document 1 can insulate and fix the stator coil without performing the insulating varnish impregnation treatment on the stator coil. However, although the thermosetting resin in a semi-cured state is composed of an epoxy resin or the like, and the insulating film base material is composed of a resin such as polyethylene naphthalate, polyethylene terephthalate, polyimide or the like, there is no description about the detailed composition and physical properties of these materials, and the properties of the thermosetting resin with respect to flexibility and fluidity are not evaluated, so that there is a problem that it is unclear whether or not the thermosetting resin has a property that the thermosetting resin flows and penetrates into fine portions between members when heated.
Accordingly, an object of the present invention is to obtain an insulating sheet having a property that a thermosetting resin flows when heated and penetrates into a fine portion of a gap of a member to be insulated, and a method for manufacturing the same. Further, an object is to obtain a rotating electric machine with improved insulation reliability, heat dissipation, and vibration resistance.
Technical scheme for solving technical problem
The disclosed insulating sheet comprises a sheet-like base material having pores, voids or meshes, and an insulating resin layer composed of a thermosetting resin composition provided on one or both surfaces of the base material; the base material is formed by a single layer sheet of any one of insulating paper, an insulating film, non-woven fabric and mesh cloth or a laminated sheet formed by laminating a plurality of sheets selected from the insulating paper, the insulating film, the non-woven fabric and the mesh cloth; the insulating resin layer is in an uncured or semi-cured state; the thermosetting resin composition has a first thermosetting resin which is solid at 25 ℃, a second thermosetting resin which is liquid at 25 ℃, and a latent curing agent which is reactive inert at 60 ℃ or lower; the mass part of the first thermosetting resin is in the range of 10 to 90 mass parts, assuming that the total mass of the first thermosetting resin and the second thermosetting resin is 100 mass parts.
The disclosed rotating electrical machine includes an insulating sheet and a stator, wherein the insulating sheet includes a sheet-like base material having a hole, a void, or a mesh, and an insulating resin layer made of a thermosetting resin composition provided on one surface or both surfaces of the base material, and the stator includes a cylindrical stator core and a stator coil disposed in a slot formed in the stator core with the insulating sheet obtained by curing the insulating resin layer interposed therebetween; the insulating sheet insulates between the stator core and the stator coil, and fixes the stator core and the stator coil.
The method for producing an insulating sheet disclosed by the present invention is a method for producing an insulating sheet comprising a sheet-like base material having pores, voids or meshes and an insulating resin layer comprising a thermosetting resin composition provided on one or both surfaces of the base material, the method comprising: a first step of stirring and mixing a first thermosetting resin which is solid at 25 ℃, a second thermosetting resin which is liquid at 25 ℃, a latent curing agent which is reactive at 60 ℃ or lower, a plurality of granular inorganic fillers having a maximum particle diameter smaller than the thickness of the insulating resin layer and an average particle diameter smaller than 0.5 times the thickness of the insulating resin layer, and an organic solvent for dilution to prepare a slurry of a thermosetting resin composition; and a second step of applying the slurry prepared in the first step to one or both surfaces of a base material formed of a single-layer sheet of any one of insulating paper, an insulating film, a nonwoven fabric and a mesh cloth, or a laminated sheet in which a plurality of sheets selected from the insulating paper, the insulating film, the nonwoven fabric and the mesh cloth are laminated, and then drying the slurry to an uncured or semi-cured state; in the thermosetting resin composition in the first step, the mass part of the first thermosetting resin is in the range of 10 to 90 parts by mass, assuming that the total mass of the first thermosetting resin and the second thermosetting resin is 100 parts by mass.
Effects of the invention
In the insulating sheet disclosed in the present invention, the sheet-like base material having the holes, voids or meshes is formed of a single-layer sheet of any one of insulating paper, an insulating film, a nonwoven fabric and a mesh fabric or a laminated sheet in which a plurality of sheets selected from the insulating paper, the insulating film, the nonwoven fabric and the mesh fabric are laminated, the insulating resin layer is in an uncured or semi-cured state, the thermosetting resin composition comprises a first thermosetting resin which is solid at 25 ℃, a second thermosetting resin which is liquid at 25 ℃, and a latent curing agent which is reactive inert at 60 ℃ or lower, and the mass part of the first thermosetting resin is in the range of 10 to 90 parts by mass when the total mass of the first thermosetting resin and the second thermosetting resin is taken as 100 parts by mass, it is therefore possible to obtain an insulating sheet having a characteristic that a thermosetting resin flows when heated to penetrate into a minute part of the gap of a member as an insulating object. Further, since the thermosetting resin penetrates into a minute part of the gap between the members, the members can be insulated from each other and fixed.
A rotating electrical machine according to the present invention includes the insulating sheet according to the present invention, and a stator including a cylindrical stator core and a stator coil arranged in a slot formed in the stator core with the insulating sheet obtained by curing an insulating resin layer interposed therebetween, and therefore an air layer between the stator coil and the stator core is eliminated, and insulation reliability, heat radiation performance, and vibration resistance of the rotating electrical machine can be improved.
The method for manufacturing an insulating sheet disclosed by the invention comprises the following steps: a first step of stirring and mixing a first thermosetting resin, a second thermosetting resin, a latent curing agent, a plurality of granular inorganic fillers, and a diluent to prepare a slurry of a thermosetting resin composition; and a second step of drying the slurry prepared in the first step to an uncured or semi-cured state after coating the slurry on one or both surfaces of the base material 2; in the thermosetting resin composition in the first step, the mass part of the first thermosetting resin is in the range of 10 to 90 parts by mass, assuming that the total mass of the first thermosetting resin and the second thermosetting resin is 100 parts by mass; therefore, the insulating sheet 1 having the property that the thermosetting resin flows when heated and penetrates into a minute part of the gap of the member to be insulated can be manufactured. Further, since the thermosetting resin penetrates into a fine portion of the gap between the members, the members can be insulated from each other and fixed.
Drawings
Fig. 1 is a cross-sectional view showing an outline of an insulating sheet according to embodiment 1.
Fig. 2 is a cross-sectional view showing an outline of an insulating sheet according to embodiment 1.
Fig. 3 is a cross-sectional view schematically showing another insulating sheet according to embodiment 1.
Fig. 4 is a cross-sectional view schematically showing another insulating sheet according to embodiment 1.
Fig. 5 is a diagram illustrating a change in storage shear modulus with respect to temperature of the insulating resin layer of the insulating sheet of embodiment 1.
Fig. 6 is a diagram illustrating a change in loss modulus with respect to temperature of the insulating resin layer of the insulating sheet of embodiment 1.
Fig. 7 is a diagram illustrating a change in complex viscosity of the insulating resin layer of the insulating sheet of embodiment 1 with respect to temperature.
Fig. 8 is a diagram showing a process for producing an insulating sheet according to embodiment 1.
Fig. 9 is a diagram showing another manufacturing process of the insulating sheet of embodiment 1.
Fig. 10 is a perspective view showing an outline of a stator of a rotating electric machine according to embodiment 2.
Fig. 11 is a cross-sectional view schematically showing a stator of a rotating electric machine according to embodiment 2.
Fig. 12 is a main part sectional view showing an outline of a stator of a rotating electric machine according to embodiment 2.
Fig. 13 is a sectional view of the stator cut at a sectional position a-a of fig. 12.
Fig. 14 is an enlarged cross-sectional view of a portion shown in B of fig. 12.
FIG. 15 is a table showing the formulation of the thermosetting resin composition of the example.
FIG. 16 is a table showing the formulation of a thermosetting resin composition of a comparative example.
FIG. 17 is a table showing the evaluation results of examples.
Fig. 18 is a table showing the evaluation results of the comparative example.
Detailed Description
An insulating sheet, a method for manufacturing the insulating sheet, and a rotating electrical machine according to an embodiment of the present invention will be described below with reference to the drawings. In the drawings, the same or corresponding members and portions are denoted by the same reference numerals.
Embodiment 1.
FIG. 1 is a sectional view showing the outline of an insulating sheet 1 according to embodiment 1, FIG. 2 is a sectional view showing the outline of an insulating sheet 1 different from that of FIG. 1, FIG. 3 is a cross-sectional view showing an outline of another insulating sheet 1 according to embodiment 1, namely, a composite insulating sheet 10, fig. 4 is a cross-sectional view showing an outline of the composite insulating sheet 10 different from fig. 3, fig. 5 is a view explaining a change in storage shear modulus of the insulating resin layer 3 of the insulating sheet 1 with respect to temperature, fig. 6 is a graph illustrating a change in loss modulus with respect to temperature of the insulating resin layer 3 of the insulating sheet 1, FIG. 7 is a graph illustrating a change in complex viscosity of the insulating resin layer 3 of the insulating sheet 1 with respect to temperature, fig. 8 is a diagram showing a manufacturing process of an insulating sheet 1 according to embodiment 1, and fig. 9 is a diagram showing another manufacturing process of the insulating sheet 1. The insulating sheet 1 is a sheet that is disposed between members to be insulated, insulates the members from each other, and fixes the members.
< insulating sheet 1>
The insulating sheet 1 includes a sheet-like base material 2 having pores, voids, or meshes, and an insulating resin layer 3 made of a thermosetting resin composition provided on one surface or both surfaces of the base material 2. In the example of the insulating sheet 1 shown in fig. 1, the insulating resin layer 3 is formed on one surface of the base material 2, and in the example of the insulating sheet 1 shown in fig. 2, the insulating resin layers 3 are formed on both surfaces of the base material 2. The base material 2 is formed of a single-layer sheet of any one of insulating paper, an insulating film, a nonwoven fabric, and a mesh fabric. The insulating resin layer 3 is in an uncured or semi-cured state. Through-holes 4 penetrating both surfaces of the base material 2 are formed from the holes, voids, or meshes of the base material 2. The inside of the through-hole 4 is filled with a thermosetting resin composition constituting the insulating resin layer 3 as an in-hole insulating resin 3 a. In the preparation of the insulating sheet 1, there is no problem even if the inside of the through-holes 4 is not completely filled with the hole-inside insulating resin 3 a. In the curing treatment step of the insulating resin layer 3, the insulating resin layer 3 flows, and therefore the inside of the through-hole 4 is filled with the hole-inside insulating resin 3 a. In the following description, the base material 2 will be referred to as "base material 2" unless the material of the base material 2 such as insulating paper or insulating film is specifically distinguished.
Another insulating sheet 1, i.e., a composite insulating sheet 10 will be explained. The composite insulating sheet 10 includes a sheet-like base material 2 having pores, voids, or meshes, and an insulating resin layer 3 made of a thermosetting resin composition provided on one surface or both surfaces of the base material 2. In the example of the composite insulating sheet 10 shown in fig. 3, the insulating resin layer 3 is formed on one surface of the base material 2, and in the example of the composite insulating sheet 10 shown in fig. 4, the insulating resin layer 3 is formed on both surfaces of the base material 2. The base material 2 is composed of a laminated sheet in which a plurality of sheets 2a selected from insulating paper, an insulating film, a nonwoven fabric, and a mesh fabric are laminated with an adhesive 5 interposed therebetween. Through-holes 4 penetrating both surfaces of the base material 2 are formed from the holes, voids, or meshes of the base material 2. In the composite insulating sheet 10, the through-holes 4 are formed in the substrate 2 after the sheets 2a are laminated, and the through-holes 4 are also formed in the adhesive 5 portion. The inside of the through-hole 4 is filled with a thermosetting resin composition constituting the insulating resin layer 3 as an in-hole insulating resin 3 a. In the preparation of the insulating sheet 1, there is no problem even if the inside of the through-holes 4 is not completely filled with the hole-inside insulating resin 3 a. In the curing step of the insulating resin layer 3, the insulating resin layer 3 flows, and therefore the inside of the through-hole 4 is filled with the hole insulating resin 3 a. The adhesive 5 may be the insulating resin layer 3. Since the insulating resin layer 3 has flexibility and has high adhesion strength with the sheets 2a, the sheets 2a can be adhered to each other by heat and pressure bonding.
The plurality of sheets 2a constituting the substrate 2 may be made of the same material or different materials. In the composite insulating sheet 10 shown in fig. 3 and 4, the base material 2 is constituted by 3 sheets 2a, but the number of sheets 2a is not limited thereto. However, if the number of sheets 2a increases, the thickness of the composite insulating sheet 10 increases, and therefore the number of sheets 2a is preferably about 3.
< substrate 2>
The material of the insulating paper, insulating film, nonwoven fabric, and mesh fabric constituting the base material 2 is resin fiber having insulating properties, silica fiber, or the like. When the thermosetting resin composition constituting the insulating resin layer 3 contains a plurality of inorganic fillers in a granular form, the size of the pores, voids, and meshes in the direction parallel to the surface of the substrate 2 is larger than the minimum particle diameter of the plurality of inorganic fillers. In the thermosetting resin composition, the thermal conductivity of the thermosetting resin composition can be improved by the kind of the inorganic filler to be incorporated or the amount of the inorganic filler to be incorporated. When an insulating film or insulating paper having no through-hole 4 is used as the base material 2, the insulating film or insulating paper having low thermal resistance hinders heat dissipation from the stator coil to the stator core. By using, as the base material 2, an insulating film or an insulating paper having pores, voids, and meshes whose sizes are larger than the minimum particle diameter of the inorganic filler, a nonwoven fabric having voids, or a mesh fabric having meshes, the thermosetting resin composition can fill the interiors of the pores, voids, and meshes. Therefore, the thermal conductivity of the thermosetting resin composition can effectively function also in the base material 2, and the inhibition of heat dissipation by the base material 2 can be suppressed.
In addition, in the case where it is necessary to increase the thermal conductivity of the insulating sheet 1 and it is not necessary to form the thick insulating resin layer 3, the inorganic filler may not be incorporated into the thermosetting resin composition. Even when the thermosetting resin composition does not contain an inorganic filler, in order to effectively reflect the heat dissipation property of the thermosetting resin composition on the substrate 2 of the insulating sheet 1, it is necessary to use the substrate 2 of insulating paper, insulating film, nonwoven fabric, or mesh fabric having pores, voids, or meshes in the insulating sheet 1. In this case, the size of the holes, voids, and meshes in the direction parallel to the surface of the base material 2 is preferably 1 μm or more in order to fill the through-holes 4 with the thermosetting resin composition.
In the case of using insulating paper or an insulating film as the substrate 2, since the insulating paper and the insulating film do not have a void, the through-hole 4 is provided in the insulating paper and the insulating film, and a void is formed in the insulating paper and the insulating film. The shape of the pores is not limited, but when the thermosetting resin composition contains a plurality of inorganic fillers in a granular form, the dimension of the pores in the direction parallel to the surface of the substrate 2 is larger than the minimum particle diameter of the plurality of inorganic fillers, and the porosity of the pores is preferably in the range of 20% to 95%. From the viewpoint of heat dissipation properties of the substrate 2 and strength of the substrate 2, in order to fill the through-holes 4 with the thermosetting resin composition, the size of the holes in the direction parallel to the surface of the substrate 2 is 1 μm or more and larger than the average particle diameter of the inorganic filler, and the porosity of the holes is more preferably in the range of 30% to 90%. The shape and size of the pores distributed in the base material 2 may be the same or different. The pores may be uniformly distributed in the substrate 2, or may be unevenly distributed or partially arranged.
When a nonwoven fabric is used as the substrate 2, the nonwoven fabric may be any of general-purpose nonwoven fabrics, microfiber nonwoven fabrics, and nanofiber nonwoven fabrics. When the thermosetting resin composition contains a plurality of inorganic fillers in a granular form, the size of the voids in the nonwoven fabric in the direction parallel to the surface of the substrate 2 is larger than the minimum particle diameter of the plurality of inorganic fillers, and the void ratio of the voids is preferably in the range of 20% to 95%. In order to fill the through-hole 4 formed by the voids with the thermosetting resin composition, the size of the voids in the direction parallel to the surface of the substrate 2 is 1 μm or more and is larger than the average particle diameter of the inorganic filler, and the void ratio of the voids is more preferably in the range of 30% to 90% from the viewpoint of the heat radiation property of the substrate 2 and the strength of the substrate 2. The voids distributed in the base material 2 may be the same or different in shape and size. The in-plane distribution of the voids in the base material 2 may be uniform, or may be non-uniform or partially arranged.
When a mesh fabric is used as the base material 2 and the thermosetting resin composition contains a plurality of inorganic fillers in a granular form, the dimension of the mesh fabric in the direction parallel to the surface of the base material 2 is larger than the minimum particle diameter of the plurality of inorganic fillers, and the mesh ratio of the mesh fabric is preferably in the range of 20% to 95%. From the viewpoint of heat dissipation properties of the substrate 2 and strength of the substrate 2, in order to fill the through-holes 4 formed by the mesh with the thermosetting resin composition, the size of the mesh in the direction parallel to the surface of the substrate 2 is 1 μm or more and is larger than the average particle diameter of the inorganic filler, and the mesh ratio of the mesh is more preferably in the range of 30% to 90%. The shape and size of the mesh openings distributed in the base material 2 may be the same or different. The mesh openings may be uniformly distributed in the plane of the base material 2, or may be non-uniformly or locally arranged.
The material of the insulating paper, insulating film, nonwoven fabric, and mesh fabric forming the base material 2 is a material having insulating properties, and a known material may be appropriately selected depending on the application of the target properties such as flexibility, or a combination of a plurality of materials may be used. The material of the substrate 2 is, for example, an insulating resin material made of engineering plastic or super engineering plastic, an inorganic insulating material made of silica, alumina, or glass, or a material containing a fibrous insulating resin material or a fibrous inorganic insulating material. The insulating resin material is flexible and thus can be favorably molded, and the inorganic insulating material has a high thermal conductivity and thus can improve heat dissipation from the stator coil generating heat to the stator core. Specific examples thereof include fluororesin such as aramid paper, kraft paper, creped paper, polyacetal, polyamide, polycarbonate, modified polyphenylene ether, polybutylene terephthalate, polyethylene naphthalate, polysulfone, polyethersulfone, polyphenylene sulfide, polyether ether ketone, polyimide, polyetherimide, polytetrafluoroethylene, tetrafluoroethylene-ethylene copolymer, polyvinylidene fluoride, polyester, polyethylene, polypropylene, nylon 6, vinylon, ethylene vinyl acetate, polyacrylonitrile, polyolefin, rayon, teflon (registered trademark) or polyvinylidene fluoride, liquid crystal polymer, cellulose, vinylon, glass, silica and alumina.
The substrate 2 may be formed of a laminated sheet as shown in fig. 3 or 4. When the substrate 2 is a laminated sheet, the substrate 2 is formed by laminating either or both of an insulating paper and an insulating film, for example. The thickness of the substrate 2 can be freely selected by lamination. Further, by laminating an insulating paper and an insulating film in combination, the substrate 2 can be formed which fully exhibits the respective characteristics. When the base material 2 is formed of a plurality of sheets of insulating paper, the base material 2 is a composite insulating paper. When the substrate 2 is formed of a plurality of insulating films, the substrate 2 is a composite insulating film. When the substrate 2 is a laminated sheet, the substrate 2 includes a plurality of sheets laminated with the insulating resin layer 3 or an adhesive interposed therebetween, for example. The strength of the base material 2 can be improved by the insulating resin layer 3 or the adhesive. In addition, when the inorganic filler is incorporated into the adhesive, the thermal conductivity of the adhesive can be increased, and thus the heat dissipation effect of the base material 2 can be improved. When the plurality of sheets are bonded to each other with an adhesive interposed therebetween, the adhesive used is, for example, an acrylic or epoxy-based general-purpose adhesive or a high thermal conductivity adhesive containing a filler. In the case of an insulating sheet 1 for a rotating electrical machine, which requires high heat resistance and insulation properties, a substrate 2 formed by laminating highly heat-resistant aramid paper, polyethersulfone, polyphenylene sulfide, polyetheretherketone, polyethylene naphthalate, polyimide, or the like is preferable. In the case of the substrate 2 including the insulating paper and the insulating film and not having the through-holes 4, the through-holes 4 are provided, and holes are formed in the insulating paper and the insulating film.
< insulating resin layer 3>
The thermosetting resin composition constituting the insulating resin layer 3 has a thermosetting resin (a) as a first thermosetting resin which is solid at 25 ℃, a thermosetting resin (B) as a second thermosetting resin which is liquid at 25 ℃, and a latent curing agent which is reactive inert at 60 ℃ or less. The thermosetting resin composition may further have various inorganic fillers in a granular form. The maximum particle diameters of the plurality of inorganic fillers are smaller than the thickness of the insulating resin layer 3, and the average particle diameter is smaller than 0.5 times the thickness of the insulating resin layer 3. When the maximum particle diameter of the inorganic filler is equal to or larger than the thickness of the insulating resin layer 3, or when the average particle diameter of the inorganic filler is equal to or larger than 0.5 times the thickness of the insulating resin layer 3, the insulating sheet 1 cannot obtain surface flatness when the slurry for forming the insulating resin layer 3 is applied on the substrate 2. Further, since the compression of the insulating resin layer 3 is stopped by the high-elasticity inorganic filler, the insulating resin layer 3 cannot be efficiently compressed, the insulating resin layer 3 cannot be sufficiently filled in a fine portion of the gap where the insulating sheet 1 is arranged, and the insulating sheet 1 cannot be compressed and fixed to the stator in some cases when the stator core is formed into a cylindrical shape. The thermosetting resin composition contains a curing accelerator, a film-forming agent, a tackiness agent, an adhesion agent, and the like as required. In the following description, when both the thermosetting resin (a) and the thermosetting resin (B) are referred to without particular distinction, or when a mixed resin thereof is referred to, it is simply referred to as "thermosetting resin". Further, the normal temperature is about 25 ℃.
First, a thermosetting resin will be explained. As the thermosetting resin, known thermosetting resins such as epoxy resin, phenol resin, unsaturated polyester resin, polyurethane resin, diallyl phthalate resin, and silicone resin can be used. The thermosetting resin particularly preferably contains at least one of unsaturated polyester resins such as epoxy resin, phenol resin, or vinyl ester resin, which are widely used as insulating varnish. They are conventionally used materials and therefore can be easily used, and productivity of the insulating sheet 1 can be improved.
Specific examples of the thermosetting resin include bisphenol a type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, brominated bisphenol a type epoxy resin, brominated bisphenol F type epoxy resin, brominated bisphenol AD type epoxy resin, alicyclic epoxy resin, brominated alicyclic epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, brominated phenol novolac type epoxy resin, brominated cresol novolac type epoxy resin, hydrogenated bisphenol a type epoxy resin, triglycidyl isocyanurate, hydantoin type epoxy resin, heterocyclic epoxy resin, aralkyl type epoxy resin having a biphenyl skeleton, dicyclopentadiene type epoxy resin, phenol novolac resin, resol type epoxy resin, epoxy (meth) acrylate resin (vinyl ester resin), urethane (meth) acrylate resin, polyether (meth) acrylate resin, epoxy resin, epoxy resin, polyester (meth) acrylate resins, and the like. These resins may also be used alone as a thermosetting resin. In addition, two or more kinds may be mixed and used as the thermosetting resin.
The thermosetting resin (A) is solid at ordinary temperature, and has a softening temperature of a melting point or a glass transition temperature of 150 ℃ or lower. More preferably, the softening temperature is 125 ℃ or lower. When the softening temperature is higher than 150 ℃, the polymerization reaction with the thermosetting resin (B) is difficult to proceed during heating, and the heating temperature in the curing treatment step needs to be increased to more than 200 ℃. Therefore, deterioration of the member to be insulated or the insulating film is induced, which is not preferable.
The thermosetting resin (a) must be dissolved in at least one of the liquid thermosetting resin (B) and the organic solvent for dilution (hereinafter referred to as a diluent). When not dissolved, a state in which the resin component is uniformly dissolved cannot be obtained in the slurry preparation step described below, and therefore, a uniform insulating resin layer 3 cannot be formed.
When the thermosetting resin (a) is an epoxy resin, from the viewpoint of improving the adhesion to the member to be insulated, an epoxy resin having an epoxy equivalent of 200 or more and a softening point in the range of 50 to 160 ℃ (hereinafter, when the lower limit and the upper limit of such a numerical value or ratio are shown, these values are referred to as "50 to 160 ℃). When the thermosetting resin (a) is an unsaturated polyester resin such as a vinyl ester resin, an unsaturated polyester resin having a softening point of 50 to 160 ℃ is also preferable. These resins are excellent in handling properties when premixed with other raw materials at normal temperature and are easily melted by heating, so that the homogeneity when mixed with other raw materials is improved.
When the thermosetting resin (a) is an epoxy resin, the thermosetting resin (B) is preferably an epoxy resin that is liquid at room temperature in order to improve the adhesion to the member to be insulated, and a bisphenol a type epoxy resin or a bisphenol F type epoxy resin is more preferably used in order to improve the dissolving power of the thermosetting resin (a). In the case where the thermosetting resin (a) is an unsaturated polyester resin, the thermosetting resin (B) is preferably a low-viscosity low-molecular-weight product of an oligomer or a monomer of the unsaturated polyester resin in order to increase the dissolving power of the thermosetting resin (a).
By using the thermosetting resin (a) and the thermosetting resin (B) which are different in state at room temperature and adjusting the mass ratio, the surface tackiness (viscosity), mechanical strength (toughness), adhesiveness, fluidity during heating, and the like of the insulating resin layer at room temperature can be controlled. The mass part of the thermosetting resin (a) is in the range of 10 to 90 mass parts, more preferably 15 to 85 mass parts, with the total mass of the thermosetting resin (a) and the thermosetting resin (B) being 100 mass parts.
The mass ratio (A/B) of the thermosetting resin (A) to the thermosetting resin (B) is preferably in the range of 10/90 to 90/10, when the ratio of the thermosetting resin (A) to the thermosetting resin (B) is considered from the viewpoint of the mass ratio. When the mass ratio (a/B) is less than 10/90, since a large amount of liquid resin is present, a stable insulating resin layer 3 cannot be obtained after drying, and thus cannot be peeled from the release substrate. When the mass ratio (a/B) is higher than 90/10, the toughness (material adhesion strength) of the insulating resin layer 3 is lowered because the amount of solid resin is large. Therefore, the insulating resin layer 3 is likely to be cracked or chipped at the time of drying or peeling from the release substrate, and the handling property of the insulating sheet 1 is deteriorated.
In order to produce the insulating resin layer 3 having high toughness and stability, the mass ratio (A/B) is preferably in the range of 15/85 to 85/15. In addition, in order to ensure adhesiveness and fluidity during heating, which can facilitate the adhesion to the member to be insulated, the mass ratio (A/B) is preferably in the range of 15/85-50/50. On the other hand, when the adhesiveness of the surface of the insulating resin layer 3 is not required (for example, when the adhesiveness deteriorates the workability of the insulating sheet 1), the mass ratio (a/B) is preferably in the range of 50/50 to 85/15 in order to reduce the surface adhesiveness. In this case, since the thermosetting resin (a) which is solid at normal temperature is contained in a large amount, the fluidity during heating is lowered. When it is necessary to reduce the surface tackiness while securing the fluidity during heating, the insulating resin layer 3 in the semi-cured state in which the curing reaction is slightly progressed may be formed by a formulation in which the proportion of the thermosetting resin (B) which is liquid at normal temperature is increased, or by increasing the drying temperature or by extending the drying time.
Next, a curing agent such as a latent curing agent contained in the thermosetting resin composition will be described. The thermosetting resin composition contains a curing agent for curing the thermosetting resin in addition to the thermosetting resin (a) and the thermosetting resin (B). The curing agent is not particularly limited, and a known curing agent can be appropriately selected depending on the type of the thermosetting resin. As the curing agent, amines, phenols, acid anhydrides, imidazoles, polythiol curing agents, polyamide resins, and the like can be used.
Specific examples of the curing agent include alicyclic acid anhydrides such as methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride and nadic anhydride, aliphatic acid anhydrides such as dodecenylsuccinic anhydride, aromatic acid anhydrides such as phthalic anhydride and trimellitic anhydride, dicyandiamide, aromatic diamines such as 4, 4' -diaminodiphenylsulfone, organic dihydrazides such as adipic acid dihydrazide, boron halide amine complexes such as boron trifluoride, boron trichloride and boron tribromide, tris (dimethylaminomethyl) phenol, dimethylbenzylamine, 1, 8-diazabicyclo (5,4,0) undecene and derivatives thereof, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 1-cyanoethyl-2-methylimidazole and the like, bisphenol A, bisphenol F, and imidazole, Polyhydric phenol compounds such as bisphenol S, phenol novolac resin, cresol novolac resin, and p-hydroxystyrene resin, and organic peroxides.
Among the above curing agents, typical examples of the boron halide amine complex include boron trifluoride monoethylamine complex, boron trifluoride diethylamine complex, boron trifluoride isopropylamine complex, boron trifluoride chloroaniline complex, boron trifluoride-triallylamine complex, boron trifluoride benzylamine complex, boron trifluoride aniline complex, boron trichloride monoethylamine complex, boron trichloride phenol complex, boron trichloride piperidine complex, boron trichloride dimethylsulfide complex, boron trichloride N, N-dimethyloctylamine complex, boron trichloride N, N-dimethyldodecylamine complex, and boron trichloride N, N-diethyldioctylamine complex. These curing agents may be used alone or in combination of 2 or more.
The amount of the curing agent to be incorporated may be appropriately adjusted depending on the types of the thermosetting resin and the curing agent to be used. In general, the mass part of the curing agent is preferably 0.1 to 200 parts by mass, based on 100 parts by mass of the thermosetting resin.
When an epoxy resin is used as the thermosetting resin, a latent curing agent which is inert to reaction at 60 ℃ or lower is suitable as the curing agent from the viewpoint of storage stability of the insulating resin layer 3, curability, physical properties of the cured resin, and the like. Specific examples of the latent curing agent include halogenated boron amine complexes such as boron trifluoride-amine complexes, and aromatic diamines such as dicyandiamide, organic acid hydrazide, and 4, 4' -diaminodiphenylsulfone. By heating the insulating sheet 1 having these latent curing agents at a temperature lower than the reaction activity initiation temperature, the fluidized insulating resin layer 3 enters the gap between the stator coil and the stator core, and the fixation and heat dissipation properties of the member to be insulated can be effectively improved. These latent curing agents may be used alone or in combination of 2 or more. The amount of the latent curing agent to be incorporated is 0.3 to 2.0 in terms of equivalent ratio to the epoxy resin as the thermosetting resin, and is more preferably 0.5 to 1.5 in terms of stability of the cured product characteristics.
In the case of using an unsaturated polyester resin as the thermosetting resin, an organic peroxide exemplified as a specific example of the curing agent is used as a reaction initiator for initiating the polymerization reaction. The organic peroxide is not particularly limited as long as the 10-hour half-life temperature is 40 ℃ or higher, and any organic peroxide known in the art can be used. Specific examples of the organic peroxide include peroxides such as ketone peroxides, peroxy ketals, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxyesters, and peroxydicarbonates. These organic peroxides may be used alone or in combination of 2 or more.
By selecting an organic peroxide having a high activation temperature, the usable time of the insulating resin layer 3 (i.e., the usable time of the insulating sheet 1) can be increased. The 10-hour half-life temperature of the organic peroxide is preferably 80 ℃ or higher from the viewpoint of ensuring a usable time of the insulating resin layer 3 suitable for the immersion treatment of the stator coil. In order to efficiently cure the insulating resin layer 3, the 10-hour half-life temperature of the organic peroxide is preferably equal to or lower than the set temperature of the curing oven used to cure the insulating resin layer 3.
Specific examples of the organic peroxide having such a 10-hour half-life temperature include 1, 1-di (t-butylperoxy) cyclohexane, 1-di (t-hexylperoxy) -3,3, 5-trimethylcyclohexane, 1-di (t-butylperoxy) -2-methylcyclohexane, 2-di (4, 4-di (t-butylperoxy) cyclohexyl) propane, n-butyl-4, 4-di (t-butylperoxy) valerate, 2-di (t-butylperoxy) butane, t-hexylperoxyisopropyl monocarbonate, t-butylperoxymaleic acid, t-butylperoxy-3, 5, 5-trimethylhexanoic acid, t-butylperoxylauric acid, t-butylperoxyisopropyl monocarbonate, 1-di (t-butylperoxy) cyclohexane, 1-di (t-hexylperoxy) cyclohexane, 1, 4-di (t-butylperoxy) n-butyl-pentanoic acid, n-butyl-isopropyl monocarbonate, tert-butyl peroxyl, tert-butyl peroxyisopropyl monocarbonate, and tert-butyl peroxyl, T-butylperoxybenzoate, t-butylperoxyacetate, t-hexylperoxybenzoate, 2, 5-dimethyl-2, 5-di (benzoylperoxy) hexane, t-butylperoxy 2-ethylhexyl monocarbonate, di (2-t-butylperoxyisopropyl) benzene, dicumyl peroxide, di-t-hexylperoxide, 2, 5-dimethyl-2, 5-di (t-butylperoxy) hexane, di-t-hexylperoxide, t-butylcumyl peroxide, di-t-butylperoxy) hexanePeroxide, 2, 5-dimethyl-2, 5-di (tert-butylperoxy) hex-3-yne, p-xylene
Figure BDA0003363490960000141
Alkyl hydroperoxides, t-butylperoxyallyl monocarbonate, methyl ethyl ketone peroxide, 1,3, 3-tetramethylbutyl hydroperoxide, t-butyl hydroperoxide, cumin hydroperoxide, diisopropylbenzene hydroperoxide, and the like. These may be used alone or in combination of 2 or more.
The amount of the organic peroxide to be incorporated is not particularly limited, but is usually 0.1 to 10 parts by mass when the total mass of the polyester resin as the thermosetting resin is 100 parts by mass. More preferably 0.5 to 5 parts by mass. If the amount of the organic peroxide to be incorporated is less than 0.1 part by mass, the crosslinking density decreases, and curing may be insufficient. On the other hand, if the amount of the organic peroxide to be incorporated is more than 10 parts by mass, the usable time of the insulating resin layer 3 tends to be significantly shortened.
Next, various particulate inorganic fillers that the thermosetting resin composition can have will be described. The thermosetting resin composition may contain an inorganic filler from the viewpoint of improving the thermal conductivity and mechanical strength, increasing the film thickness of the insulating resin layer 3, and the like. Since the maximum particle size of the plurality of inorganic fillers is smaller than the thickness of the insulating resin layer 3 and the average particle size is smaller than 0.5 times the thickness of the insulating resin layer 3, the inorganic fillers do not protrude from the insulating resin layer 3 and the inorganic fillers can be easily dispersed and disposed inside the insulating resin layer 3. The inorganic filler is not particularly limited, and a known inorganic filler can be appropriately selected according to the purpose. The inorganic filler may or may not be surface-treated with a silane coupling agent, a titanate coupling agent, or the like.
Specific examples of the inorganic filler include crystalline silica, fused silica, alumina, talc, clay, calcium carbonate, calcium silicate, titanium dioxide, silicon nitride, aluminum hydroxide, aluminum nitride, boron nitride, glass, barium sulfate, magnesium oxide, beryllium oxide, mica, and magnesium oxide. The shape of the filler is suitably a flake or a sphere, but may be a subsphaeroidal shape, a flake, a fiber, a milled fiber, a whisker, or the like. These fillers may be used alone or in combination of 2 or more.
In addition, in order to improve crack resistance and impact resistance of the insulating resin layer 3 after curing, a resin filler such as a thermoplastic resin, a rubber component, or various oligomers may be added to the insulating resin layer 3. Specific examples of the thermoplastic resin include butyral resins, polyvinyl acetal resins, polyamide resins, aromatic polyester resins, phenoxy resins, MBS resins (methyl methacrylate-butadiene-styrene copolymers), ABS resins (acrylonitrile-butadiene-styrene copolymers), acrylic resins, and the like, and can be modified with silicone oils, silicone resins, silicone rubbers, fluororubbers, and the like. In addition, various plastic powders, various engineering plastic powders, and the like may be added.
The amount of the filler to be incorporated is not limited as long as the thermosetting resin composition can be uniformly mixed, and is usually 70% by volume or less based on the total amount of the thermosetting resin composition, and more preferably 65% by volume or less in view of the workability of mixing. If the amount of the filler is more than 70 vol%, the filler cannot be uniformly mixed with the resin composition, and the reproducibility of the characteristics of the insulating resin 3 tends not to be obtained. When the insulating sheet 1 is used by being bent, the flexibility needs to be improved, and therefore, it is more preferably 50% by volume or less. In addition, in the case where it is necessary to increase the thermal conductivity of the insulating sheet 1 and it is not necessary to form the thick insulating resin layer 3, a filler may not be incorporated into the thermosetting resin composition. Even in the case where no filler is incorporated, in order to effectively reflect the heat dissipation property of the thermosetting resin composition on the base material 2 of the insulating sheet 1, it is necessary to use the base material 2 of insulating paper, insulating film, nonwoven fabric, or mesh fabric having pores, voids, or meshes in the insulating sheet 1.
The insulating sheet 1 is inserted into a gap portion formed between members to be insulated (for example, between a stator coil and a stator core) and serves as phase-to-phase insulation. Therefore, the maximum particle diameter of the inorganic filler in the thermosetting resin composition is preferably smaller than the size obtained by subtracting the thickness of the base material 2 of the insulating sheet 1 from the size of the gap, and the average particle diameter is preferably smaller than 0.5 times the size. For example, when the actual measurement size obtained by subtracting the thickness of the base material 2 from the size of the gap is 10 μm to 100 μm inclusive of the tolerance, an inorganic filler having a maximum particle diameter of 10 μm or less and an average particle diameter of 5 μm or less is selected. When the maximum particle diameter of the inorganic filler is equal to or larger than a size obtained by subtracting the thickness of the base material 2 of the insulating sheet 1 from the size of the gap, or when the average particle diameter of the inorganic filler is equal to or larger than 0.5 times the size, the insulating sheet 1 cannot have surface flatness, and the workability in the process of inserting the insulating sheet 1 into the gap is lowered. Further, since the compression of the insulating resin layer 3 is stopped by the high-elasticity inorganic filler, the insulating resin layer 3 cannot be efficiently compressed, the insulating resin layer 3 cannot be sufficiently filled in a fine portion of the gap where the insulating sheet 1 is arranged, and the insulating sheet 1 cannot be compressed and fixed to the stator in some cases when the stator core is formed into a cylindrical shape.
Next, a curing accelerator, a film-forming property-imparting agent, a tackiness-imparting agent, an adhesion-imparting agent, and the like which the thermosetting resin composition may have as necessary will be described.
In order to accelerate the curing reaction, the thermosetting resin composition may have a curing accelerator. The curing accelerator is not particularly limited, and a known curing accelerator can be appropriately selected depending on the type of the thermosetting resin. Specific examples of the curing accelerator include tertiary amines, imidazoles, and amine adducts. From the viewpoint of storage stability of the insulating resin layer, curability, physical properties of the cured resin, and the like, a curing accelerator which is reactive at 60 ℃ or lower is more preferable. The amount of the curing accelerator to be incorporated is usually 0.01 to 10 parts by mass, more preferably 0.02 to 5.0 parts by mass, based on 100 parts by mass of the total mass of the thermosetting resin. When the curing accelerator is less than 0.01 part by mass, the effect of accelerating the curing reaction is poor, and when it is more than 10 parts by mass, the pot life tends to be shortened.
The thermosetting resin composition may have a film-forming property-imparting agent for the purpose of improving film-forming properties such as thickness uniformity and surface smoothness. The film-forming property-imparting agent may be, for example, a thermoplastic resin. The thermosetting resin composition has a thermoplastic resin with a weight average molecular weight within a range of 10,000-100,000, and the thermoplastic resin is within a range of 1-100 parts by mass when the total mass of the thermosetting resin (A) and the thermosetting resin (B) is 100 parts by mass. The content is more preferably in the range of 5 to 80 parts by mass so as not to impair the curing properties of the thermosetting resin. When the thermosetting resin composition has the thermoplastic resin defined as above, the film forming properties such as the uniformity of thickness and the surface smoothness of the thermosetting resin composition can be effectively improved. The thermoplastic resin is not particularly limited, and a known thermoplastic resin can be appropriately selected depending on the kind of the thermosetting resin. Specific examples of the thermoplastic resin include phenoxy resins and saturated polyester resins. These film-forming property-imparting agents may be used alone or in combination of 2 or more.
When the weight average molecular weight of the thermoplastic resin is less than 10,000, improvement of film-forming properties cannot be achieved. When the weight average molecular weight of the thermoplastic resin is more than 100,000, the dispersibility in the liquid thermosetting resin (B) is poor, and a slurry cannot be prepared. The amount of the film-forming property-imparting agent incorporated is usually 1 to 40 parts by mass, more preferably 5 to 30 parts by mass, based on 100 parts by mass of the total mass of the thermosetting resin (a) and the thermosetting resin (B), from the viewpoints of curing acceleration, physical properties of the cured resin, and the like. If the amount of the film-forming property-imparting agent is less than 1 part by mass, the effect of improving the film-forming property is poor, and if the amount is more than 40 parts by mass, the dispersibility in the liquid thermosetting resin (B) is poor, and a slurry cannot be prepared.
In order to improve the surface tackiness of the insulating resin layer 3, the thermosetting resin composition may have a tackiness imparting agent. The adhesion imparting agent is not particularly limited as long as it has a weight average molecular weight of 10,000 to 200,000, and a known adhesion imparting agent can be appropriately selected depending on the type of the thermosetting resin. Specific examples of the tackiness imparting agent include terpene resins, rosin resins, natural rubbers, styrene elastomers, polyvinyl acetal resins, polyvinyl formal resins, and polyvinyl butyral resins. These adhesion-imparting agents may be used alone or in combination of 2 or more.
When the weight average molecular weight of the tackiness-imparting agent is less than 10,000, improvement of tackiness cannot be achieved. When the weight average molecular weight of the tackiness-imparting agent is greater than 200,000, the dispersibility of the tackiness-imparting agent in the liquid thermosetting resin (B) is poor, and a slurry cannot be prepared. The amount of the adhesion-imparting agent incorporated is usually 1 to 20 parts by mass, more preferably 2 to 10 parts by mass, based on 100 parts by mass of the total mass of the thermosetting resin, from the viewpoints of curing acceleration, physical properties of the cured resin, and the like. If the amount of the adhesion-imparting agent is less than 1 part by mass, the effect of improving the surface adhesion is poor, and if the amount is more than 20 parts by mass, the dispersibility in the liquid thermosetting resin (B) is poor, and a slurry cannot be prepared.
The thermosetting resin composition may have an adhesion-imparting agent in order to improve the adhesion at the interface between the thermosetting resin and the inorganic filler or at the interface between the insulating resin layer 3 and the member to be insulated. The adhesion-imparting agent is not particularly limited, and a known adhesion-imparting agent can be appropriately selected depending on the type of the thermosetting resin or the inorganic filler. Specific examples of the adhesion-imparting agent include silane coupling agents such as γ -glycidoxypropyltrimethoxysilane, N- β (aminoethyl) γ -aminopropyltriethoxysilane, N-phenyl- γ -aminopropyltrimethoxysilane and γ -mercaptopropyltrimethoxysilane. These adhesion imparting agents may be used alone or in combination of 2 or more. The amount of the adhesion-imparting agent to be incorporated may be appropriately set in accordance with the type of the thermosetting resin or the adhesion-imparting agent to be used, and is preferably 0.01 to 5 parts by mass, based on 100 parts by mass of the total mass of the thermosetting resin.
The thermosetting resin composition may further contain an anti-settling agent or a dispersant for inhibiting settling of solid powder such as an inorganic filler in the thermosetting resin, an antifoaming agent for preventing generation of voids, an anti-blocking agent or a slip property improving agent such as polymer beads for preventing blocking between the insulating resin layers 3, a coating material fixing agent, an antioxidant, a flame retardant, a colorant, a thickener, a surfactant, and the like.
< Properties of insulating resin layer 3>
The characteristics of the insulating resin layer 3 will be explained. The insulating resin layer 3 preferably has high surface smoothness and flexibility. The in-plane distribution of the thickness of the insulating resin layer 3 is within ± 30% of the average value of the thickness of the insulating resin layer 3, for the purpose of good adhesion to the member to be insulated and no air layer being generated between the cured insulating resin layer 3 and the member to be insulated.
The insulating resin layer 3 has flexibility such that cracking does not occur even when bent 180 degrees at 25 ℃. If the insulating resin layer 3 is dried by excessive heating, the curing reaction of the thermosetting resin proceeds in addition to the volatilization of the diluent, and the flexibility of the insulating resin layer 3 may be lost. When the flexibility of the insulating resin layer 3 is lost, the insulating resin layer 3 does not have flexibility conforming to the surface shape of the members, and therefore, when the insulating sheet 1 is disposed in the gap between the members, the insulating resin layer 3 may be cracked. Alternatively, after the insulating resin layer 3 is cured by heating, the insulating resin layer 3 may not be bonded and fixed to the member.
If the thickness of the insulating resin layer 3 is too large, the internal stress is high, and cracking may occur at 180-degree bending. The thickness of the insulating resin layer 3 is preferably 1 μm to 500 μm, and more preferably 5 μm to 300 μm in order to completely fill the gap between the members to be insulated. When the thickness is less than 1 μm, it is difficult to form the insulating resin layer 3 having no pin hole. When the thickness is more than 500. mu.m, the possibility of cracking in the 180-degree bending test is high.
The thickness of the insulating resin layer 3 is formed to fall within a range of 1.1 to 2.0 times the difference between the gap in which the insulating sheet 1 is disposed and the thickness of the substrate 2. More preferably, it is formed to fall within a range of 1.3 times to 1.7 times. By forming the thickness of the insulating resin layer 3 within the predetermined range, the insulating resin layer 3 can be sufficiently filled in the minute part of the gap where the insulating sheet 1 is arranged. In addition, when the insulating sheet 1 is disposed in a rotating electrical machine, deterioration in the assembling property of the rotating electrical machine can be suppressed. Specifically, when the size obtained by subtracting the thickness of the base material 2 from the size of the gap is 100 μm, the thickness of the insulating resin layer 3 is preferably 110 to 200 μm, and more preferably 130 to 170 μm. When the thickness is less than 110 μm, the heated insulating resin layer 3 cannot sufficiently fill the minute part of the gap. When the thickness is more than 200 μm, a gap is generated between the slots when the stator of the rotating electric machine is formed, and therefore, the stator cannot be formed into a cylindrical shape, and the assembling property of the stator may be deteriorated.
The thickness (total thickness) of the insulating resin layer 3 provided on the insulating sheet 1 is compressed by 10% or more at 25 ℃ under a pressure of 25MPa, and if dimensional tolerances of gaps between members configuring the insulating sheet 1 are taken into consideration, the thickness is more preferably compressed by 20% or more. The nonvolatile content of the insulating resin layer 3 is 97 parts by mass or more, assuming that the total mass of the thermosetting resin composition is 100 parts by mass. Since the nonvolatile content of the insulating resin layer 3 is 97 parts by mass or more, if the resin layer is completely cured, the volume shrinkage is 3% to 10%. Since the substrate 2 of the insulating sheet 1 is hardly compressed under a pressure of 25MPa depending on the kind, the thickness of the insulating resin layer 3 needs to be larger than the dimension obtained by subtracting the thickness of the substrate 2 from the dimension of the gap by 10% or more. When the thickness of the insulating sheet 1 is compressed by less than 10% at 25 ℃ and 25MPa, even if the gap is filled when the insulating sheet 1 is disposed, a minute gap may be generated by curing shrinkage of the insulating resin layer 3.
When the insulating sheet 1 is used by being stuck to a member in advance, the insulating resin layer 3 having surface tackiness (tackiness) at 25 ℃ is preferable. On the other hand, if the insulating sheet 1 is previously adhered to a member, the workability is deteriorated, and the surface tackiness of the insulating resin layer 3 can be lost while maintaining flexibility and compressibility by the mass ratio of the thermosetting resin and the drying conditions. As an index of no surface tackiness, it was determined that no tackiness was observed even when the member was pressed against an insulating object at 40 ℃ under a pressure of 2 MPa. When the insulating sheet 1 is adhered under such a condition, the surface adhesiveness is increased by the operation environment temperature (25 to 35 ℃), and the operability of the insulating sheet 1 may be deteriorated.
The insulating resin layer 3 must have flexibility that can be compressed at 25 ℃, and must flow and penetrate into fine parts between members (for example, the protruding shape and the recessed shape of the stator coil and the stator core, etc.) when heated. To obtain such characteristics, it is important that the insulating resin layer 3 be in a dried state. Flexibility can be easily judged by not cracking even when bent by 180 degrees. As a method for more quantitatively determining these properties of flexibility and fluidity, there is an elastic modulus evaluation based on a viscoelasticity measurement.
Fig. 5 shows a specific example of the viscoelasticity measurement obtained from the insulating resin layer 3 alone, and shows the change in storage shear modulus (G') with respect to temperature. Storage shear modulus at 25 ℃ (indicated as A in FIG. 5) at 1.0X 103Pa～5.0×104Pa, in the range of Pa. The storage shear modulus decreases with an increase in temperature, and the lowest value (indicated by B in FIG. 3) is from 10Pa to 2.0X 10Pa in the range of 80 ℃ to 150 DEG C3Pa, in the range of Pa. By setting the storage shear modulus within the range thus defined, the insulating resin layer 3 can obtain a predetermined compression ratio, and the insulating resin layer 3 can be made to permeate into the minute portions between the members. The insulating resin layer 3 which does not satisfy the above value does not have a predetermined compression ratio at the time of pressing, and does not have permeability into a minute portion between members.
When the minimum value of the storage shear modulus is in the range of less than 80 ℃, the insulating resin layer 3 reacts at room temperature, and the flexibility of the insulating resin layer 3 is likely to be lowered. On the other hand, if the lowest value is in the range of 150 ℃ or higher, the heating temperature required for complete curing is high, and thus the base material 2 may be deteriorated. From the viewpoint of maintaining the shape of the insulating resin layer 3 and allowing the insulating resin layer 3 to exhibit fluidity at a heating temperature, it is more preferable that the storage shear modulus at 25 ℃ is 3.0 × 103Pa～3.0×104Pa, and a lowest value of storage shear modulus in the range of 80 ℃ to 150 ℃ of 1.0 x 102Pa～5.0×102Pa is less than one tenth of the value of storage shear modulus at 25 ℃. In addition, the energy storage shearing die is above 180 DEG CThe amount was 1.0X 10 due to the influence of curing5And saturated at Pa or higher (indicated by C in FIG. 3).
Fig. 6 shows a specific example of the viscoelasticity measurement obtained from the insulating resin layer 3 alone, and shows the change in loss modulus (G ″) with respect to temperature. Loss modulus at 25 ℃ (indicated as A in FIG. 6) at 1.0X 103Pa～5.0×104Pa, in the range of Pa. The loss modulus decreases with an increase in temperature, and the lowest value (indicated by B in FIG. 6) is 10Pa to 2.0X 10Pa in the range of 80 ℃ to 150 DEG C3Pa, in the range of Pa. The maximum value of the loss tangent (tan delta) is in the range of 1.0 to 3.5 at 80 ℃ to 150 ℃. The insulating resin layer 3 having a loss modulus and a loss tangent that do not satisfy the above values does not have a predetermined compressibility during pressurization, and does not have permeability into fine portions between members.
When the lowest loss modulus or the maximum loss tangent is in the range of less than 80 ℃, the insulating resin layer 3 reacts under room temperature, and the flexibility of the insulating resin layer 3 is likely to be lowered. On the other hand, when the lowest value of the loss modulus or the maximum value of the loss tangent is in the range of 150 ℃ or more, the heating temperature required for complete curing is high, and thus the base material 2 may be deteriorated. From the viewpoint of maintaining the shape of the insulating resin layer 3 and allowing the insulating resin layer 3 to exhibit fluidity at a heating temperature, it is more preferable that the loss modulus at 25 ℃ is 3.0 × 103Pa～3.0×104Pa, and a loss modulus in the range of 80 ℃ to 150 ℃ of 1.0X 102Pa～1.0×103Pa is less than one fifth of the value at 25 ℃. The loss modulus at 180 ℃ or higher is 5.0X 10 due to the influence of curing3Pa or more (indicated by C in fig. 6), and a loss tangent of 0.2 or less.
The flexibility and fluidity of the insulating resin layer 3 can also be evaluated by complex viscosity. Fig. 7 shows a specific example of the measurement of dynamic viscoelasticity from the insulating resin layer 3 alone, and shows the change of complex viscosity with respect to temperature. Complex viscosity (indicated as A in FIG. 7) at 25 ℃ of 6.0X 102Pa·s～1.0×104Pa · s. The complex viscosity decreases with increasing temperature, and the lowest value (indicated by B in FIG. 7) is 5.0X 10 in the range of 80 ℃ to 150 ℃2Pa · s or less. By setting the complex viscosity within the above-specified range, the insulating resin layer 3 can have a predetermined compressibility, and the insulating resin layer 3 can be made to penetrate into minute portions between members. The insulating resin layer 3 having a complex viscosity not satisfying the above-mentioned value does not have a predetermined compressibility during pressurization, and does not have permeability into a fine portion between members.
In addition, from the viewpoint of maintaining the shape of the insulating resin layer 3 and allowing the insulating resin layer 3 to exhibit fluidity at a heating temperature, it is more preferable that the complex viscosity at 25 ℃ is 1.0 × 103Pa·s～5.0×103The lowest value of complex viscosity in the range of Pa.s and 80-150 ℃ is 1 Pa.s-5.0 x 102Pa · s is within a range of one tenth or less of the value at 25 ℃. The complex viscosity at 180 deg.C or above is 1.0 × 10 due to the influence of curing4And saturated at Pa · s or more (indicated by C in fig. 7).
< Properties of insulating sheet 1>
The properties of the insulating sheet 1 will be explained. The insulating sheet 1 is disposed in a gap portion formed between members to be insulated (for example, between a stator coil and a stator core), and then is heated and cured in a curing process. The heating temperature and the heating time in the curing step are different depending on the kinds of the curing agent and the curing accelerator, and are set to a heating temperature and a heating time at which the member to be insulated is not deteriorated. Specifically, the heating temperature is preferably 100 to 200 ℃, more preferably 130 to 190 ℃. The heating time is preferably 1 minute to 6 hours, more preferably 3 minutes to 2 hours.
When the heating temperature is lower than 100 ℃ or the heating time is less than 1 minute, the insulating resin layer 3 is insufficiently cured and cannot be bonded and fixed to the member. The member is rarely deteriorated even when it exceeds 6 hours at a low temperature of 100 to 170 ℃, and the member is sometimes deteriorated when it exceeds 6 hours at 170 ℃ or more, or when it is heated at a high temperature of 200 ℃ or more. Further, since the insulating sheet 1 contains almost no solvent, it can be cured by induction heating, energization heating, or the like, and when induction heating or energization heating is used, the curing process can be simplified.
In order to integrate members to be insulated and improve vibration resistance, the adhesion strength between the insulating sheet 1 and the members after curing is preferably 10N/m or more. In order to suppress the characteristic variation of vibration resistance, the adhesion force between the insulating sheet 1 and the member after curing is more preferably 20N/m or more. Therefore, when the insulating sheet 1 is used in a rotating electrical machine, the adhesion force between the stator core and the stator coil fixed by the insulating resin layer 3 is 20N/m or more. When the adhesive strength is less than 10N/m, sufficient vibration resistance cannot be obtained, and the long-term reliability of the device provided with the insulating sheet 1 is lowered.
When the insulating sheet 1 including the insulating resin layer 3 having the above-described characteristics is used, the insulating resin layer 3 can be efficiently compressed to a predetermined thickness by pressurization at normal temperature, and the insulating resin layer 3 flows by heating at the time of curing to permeate fine portions between members, so that the air layer is eliminated, and the gap between the members to be insulated can be practically filled, both of which are insulated, and both of which are fixed.
< method for producing insulating sheet 1>
A method for producing the insulating sheet 1 will be described with reference to fig. 8. An insulating sheet 1 comprising a sheet-like base material 2 having pores, voids or meshes and an insulating resin layer 3 made of a thermosetting resin composition provided on one or both surfaces of the base material 2 is produced by the following steps: a first step (S11) for preparing a slurry of a thermosetting resin composition; and a second step (S12) of applying the slurry prepared in the first step to the base material 2 and then drying the slurry to an uncured or semi-cured state.
The first step is a step of stirring and mixing a thermosetting resin (a) which is solid at 25 ℃, a thermosetting resin (B) which is liquid at 25 ℃, a latent curing agent which is reactive at 60 ℃ or less, a plurality of kinds of particulate inorganic fillers having a maximum particle diameter smaller than the thickness of the insulating resin layer 3 and an average particle diameter smaller than 0.5 times the thickness of the insulating resin layer 3, and a diluent to prepare a slurry of a thermosetting resin composition. The slurry is prepared by dissolving a solid resin and a liquid resin in a diluent (organic solvent) at normal temperature. Therefore, the preparation temperature of the slurry is normal temperature, and is within the range of 10 to 40 ℃ in consideration of the atmospheric temperature. In the thermosetting resin composition in the first step, the mass part of the thermosetting resin (a) is in the range of 10 to 90 parts by mass, assuming that the total mass of the thermosetting resin (a) and the thermosetting resin (B) is 100 parts by mass. The stirring and mixing are carried out by a stirrer. The diluent is added to the thermosetting resin composition to achieve a predetermined mixture viscosity, followed by stirring and mixing until the filler is uniformly dispersed without sedimentation.
The diluent dissolves the thermosetting resin. The diluent is evaporated or evaporated after the slurry is applied to the substrate 2 and almost completely disappears. The diluent is not particularly limited, and a known diluent can be appropriately selected depending on the type of the thermosetting resin, the inorganic filler, and the like used. Specific examples of the diluent include toluene and methyl ethyl ketone. These diluents may be used alone or in combination of 2 or more. The amount of the diluent to be incorporated is not particularly limited as long as the mixture viscosity can be kneaded, and is usually in the range of 20 to 200 parts by mass when the total mass of the thermosetting resin and the inorganic filler is 100 parts by mass.
The second step is a step of applying the slurry prepared in the first step to one or both surfaces of the base material 2 formed of a single-layer sheet of any one of insulating paper, an insulating film, a nonwoven fabric and a mesh cloth, or a laminated sheet in which a plurality of sheets selected from the group consisting of insulating paper, an insulating film, a nonwoven fabric and a mesh cloth are laminated, and then drying the slurry to an uncured or semi-cured state. The slurry is applied to the substrate 2 with a predetermined thickness by a sheet coater. The drying is carried out in a drying oven at a temperature of 80 ℃ to 160 ℃. The diluent is volatilized by drying to form the insulating resin layer 3.
The application of the slurry on the base material 2 in the second step is not limited to the application using a sheet coater. The insulating resin layer 3 may be formed by immersing the substrate 2 in the slurry prepared in the first step and volatilizing the diluent in a drying oven at a temperature of 80 to 160 ℃ while pulling up the substrate 2. At this time, the thickness of the insulating resin layer 3 is adjusted by the viscosity of the slurry. In addition, in the case of the substrate 2 having large through holes 4, the insulating resin layer 3 may not be formed in the hole portion, and therefore, it is preferable to prepare the insulating sheet 1 by a method of manufacturing the insulating sheet 1 using a sheet coater.
The nonvolatile content of the insulating resin layer 3 after drying is 97 parts by mass or more, and more preferably 99 parts by mass or more, based on 100 parts by mass of the total mass of the thermosetting resin composition. When the nonvolatile content is less than 97 parts by mass, it is difficult to release the insulating resin layer 3 from a release paper or the like as described below due to the remaining diluent. By setting the nonvolatile component within the above-specified range, the insulating resin layer 3 can be released from a release paper or the like. The insulating resin layer 3 may be in an uncured state in which only the diluent is volatilized, or may be in a semi-cured state by further heating for promoting a curing reaction after the diluent is volatilized. In the insulating sheet 1 thus produced, since adhesion (blocking) occurs in a state where the insulating resin layers 3 are in contact with each other, the surface of the insulating resin layer 3 is covered with a release film or a release paper and released at the time of use.
Another method for manufacturing the insulating sheet 1 will be described with reference to fig. 9. An insulating sheet 1 comprising a sheet-like base material 2 having pores, voids or meshes and an insulating resin layer 3 made of a thermosetting resin composition provided on one or both surfaces of the base material 2 is produced by the following steps: a first step (S111) of preparing a slurry of a thermosetting resin composition; a second step (S112) of applying the slurry produced in the first step to a release paper or a release film and then drying the slurry to an uncured or semi-cured state; and a third step (S113) of pressing and bonding the slurry dried in the second step to the base material 2. The first step (S111) is the same as the first step (S11) shown in fig. 8, and therefore, description thereof is omitted.
In the second step, the slurry is applied to a release paper or a release film with a predetermined thickness by a sheet coater. The drying of the slurry is carried out in a drying oven at a temperature of 80 to 160 ℃. The diluent is volatilized by drying to form the insulating resin layer 3.
The third step is a step of bonding the slurry dried in the second step to one surface or both surfaces of the base material 2 formed of a single-layer sheet of any one of insulating paper, an insulating film, a nonwoven fabric and a mesh cloth, or a laminated sheet in which a plurality of sheets selected from the insulating paper, the insulating film, the nonwoven fabric and the mesh cloth are laminated. The crimping is carried out at elevated temperature. In the third step, a device known in the art, such as a multifunction machine, may be used.
By this method for producing the insulating sheet 1, the insulating sheet 1 having the property that the thermosetting resin flows during heating and penetrates into a minute portion of the gap of the member to be insulated can be produced. Further, by the method of manufacturing the insulating sheet 1 shown in fig. 9, the insulating sheet 1 can be prepared by pressure-bonding and transferring the insulating resin layers 3 coated on the release paper or the release film in advance onto the base material 2, and therefore, in the case where insulating resin layers 3 having different characteristics are to be formed on both sides of the base material 2, or in the case where insulating resin layers 3 having different thicknesses are to be formed with good accuracy, these insulating sheets 1 can be easily manufactured.
As described above, in the insulating sheet of embodiment 1, the base material 2 is formed of one single-layer sheet of any one of the insulating paper, the insulating film, the nonwoven fabric and the mesh fabric or a laminated sheet in which a plurality of sheets selected from the insulating paper, the insulating film, the nonwoven fabric and the mesh fabric are laminated, the insulating resin layer 3 is in an uncured or semi-cured state, the thermosetting resin composition comprises the thermosetting resin (a) which is solid at 25 ℃, the thermosetting resin (B) which is liquid at 25 ℃ and the latent curing agent which is reactive inactive at 60 ℃ or lower, and when the total mass of the thermosetting resin (a) and the thermosetting resin (B) is 100 parts by mass, the amount of the thermosetting resin (A) is in the range of 10 to 90 parts by mass, it is therefore possible to obtain the insulating sheet 1 having the characteristic that the thermosetting resin flows when heated to penetrate into the minute part of the gap of the member as the object of insulation. Further, since the thermosetting resin penetrates into a minute part of the gap between the members, the members can be insulated from each other and fixed.
When the maximum particle diameter of the plurality of inorganic fillers is smaller than the thickness of the insulating resin layer 3 and the average particle diameter of the plurality of inorganic fillers is smaller than 0.5 times the thickness of the insulating resin layer 3, the inorganic fillers do not protrude from the insulating resin layer 3 and the inorganic fillers can be easily dispersed and disposed inside the insulating resin layer 3. Further, the insulating sheet 1 can be easily inserted into a gap portion formed between members of an insulating object (for example, between a stator coil and a stator core). When the dimensions of the pores, voids, and meshes in the direction parallel to the surface of the substrate 2 are larger than the minimum particle diameters of the plurality of inorganic fillers and the porosity of the pores, the porosity of the voids, and the mesh content of the meshes are in the range of 20% to 95%, the through-holes 4 formed by the pores, the voids, and the meshes can be easily filled with the thermosetting resin composition, and thus the substrate 2 can have heat radiation properties. Further, the base material 2 can secure strength.
When the material of the substrate 2 is an insulating resin material made of engineering plastic or super engineering plastic, an inorganic insulating material made of silica, alumina or glass, or a material containing a fibrous insulating resin material or a fibrous inorganic insulating material, the insulating resin material is flexible and can be favorably molded, and the inorganic insulating material has a high thermal conductivity and can improve heat dissipation from the heat-generating stator coil to the stator core. When the substrate 2 is a laminated sheet and the substrate 2 is formed by laminating either or both of insulating paper and an insulating film, the thickness of the substrate 2 can be freely selected by lamination. Further, by laminating an insulating paper and an insulating film in combination, the substrate 2 can be formed which fully exhibits the respective characteristics.
When the substrate 2 is a laminated sheet, and the substrate 2 includes a plurality of sheets laminated with the insulating resin layer 3 or an adhesive interposed therebetween, the strength of the substrate 2 can be improved. In addition, when the inorganic filler is incorporated into the adhesive, the thermal conductivity of the adhesive can be increased, and thus the heat dissipation effect of the base material 2 can be improved. When the thermosetting resin (a) and the thermosetting resin (B) have at least one of an epoxy resin, a phenol resin, and an unsaturated polyester resin, these are materials commonly used as insulating varnish, and therefore, they can be easily used, and the productivity of the insulating sheet 1 can be improved.
When the thermosetting resin (a) is an epoxy resin having a softening point in the range of 50 to 160 ℃, the handling property at the time of premixing with other raw materials at normal temperature is excellent, and the thermosetting resin (a) is easily melted by heating, so that the uniformity at the time of mixing with other raw materials can be improved. When the latent curing agent is any of boron trifluoride-amine complex, dicyandiamide, and organic acid hydrazide, the insulating sheet 1 having these latent curing agents is heated at a temperature lower than the reaction activity initiation temperature, and the fluidized insulating resin layer 3 enters the gap between the stator coil and the stator core, whereby the fixation and heat dissipation properties of the member to be insulated can be effectively improved.
The thermosetting resin composition has a thermoplastic resin having a weight average molecular weight in the range of 10,000 to 100,000, and when the total mass of the thermosetting resin (a) and the thermosetting resin (B) is set to 100 parts by mass, the thickness uniformity of the thermosetting resin composition can be effectively improved when the thermoplastic resin is in the range of 1 to 100 parts by mass. When the nonvolatile content of the insulating resin layer 3 is 97 parts by mass or more based on 100 parts by mass of the total amount of the thermosetting resin composition, the insulating resin layer 3 can be easily released from a release paper or the like.
The insulating resin layer 3 has a storage shear modulus of 1.0X 10 at 25 deg.C3Pa～5.0×104The lowest value of the storage shear modulus in the range of Pa and the range of 80-150 ℃ is 10 Pa-2.0 multiplied by 103In the range of Pa, the insulating resin layer 3 can have a predetermined compression ratio, and the insulating resin layer 3 can be impregnated into the minute portions between the members. The insulating resin layer has a complex viscosity of 6.0X 10 at 25 deg.C2Pa·s～1.0×104The lowest value of complex viscosity is 5.0 x 10 in the range of 80 ℃ to 150 ℃ in the range of Pa · s2When Pa · s or less, the insulating resin layer 3 can have a predetermined compressibility and the insulating resin layer 3 can penetrate into fine portions between members. The insulating resin layer 3 is formed to have a thickness falling on the insulating sheet 1In the case where the difference between the gap interval and the thickness of the substrate 2 is in the range of 1.1 to 2.0 times, the insulating resin layer 3 can be sufficiently filled in the minute part of the gap where the insulating sheet 1 is arranged. In addition, when the insulating sheet 1 is disposed in a rotating electrical machine, deterioration in the assembling property of the rotating electrical machine can be suppressed. Further, since the thermosetting resin penetrates into a minute part of the gap between the members, the members can be insulated from each other and fixed.
The method for producing the insulating sheet 1 according to embodiment 1 includes: a first step of stirring and mixing a thermosetting resin (A), a thermosetting resin (B), a latent curing agent, a plurality of granular inorganic fillers, and a diluent to prepare a slurry of a thermosetting resin composition; and a second step of drying the slurry prepared in the first step to an uncured or semi-cured state after coating the slurry on one or both surfaces of the base material 2; in the thermosetting resin composition in the first step, the mass part of the thermosetting resin (a) is in the range of 10 to 90 parts by mass, assuming that the total mass of the thermosetting resin (a) and the thermosetting resin (B) is 100 parts by mass; therefore, the insulating sheet 1 having the property that the thermosetting resin flows when heated and penetrates into a minute part of the gap of the member to be insulated can be manufactured.
Another method for producing an insulating sheet 1 according to embodiment 1 includes: a first step of stirring and mixing a thermosetting resin (A), a thermosetting resin (B), a latent curing agent, a plurality of granular inorganic fillers, and a diluent to prepare a slurry of a thermosetting resin composition; a second step of coating the slurry prepared in the first step on a release paper or a release film and then drying the slurry to an uncured or semi-cured state; and a third step of pressing and bonding the dried slurry obtained in the second step to one surface or both surfaces of the base material 2; in the thermosetting resin composition in the first step, the mass part of the thermosetting resin (a) is in the range of 10 to 90 parts by mass, assuming that the total mass of the thermosetting resin (a) and the thermosetting resin (B) is 100 parts by mass; accordingly, the insulating sheets 1 can be prepared by pressure-bonding and transferring the insulating resin layers 3 coated on the release paper or the release film in advance onto the base material 2, and therefore, in the case where insulating resin layers 3 having different characteristics are to be formed on both sides of the base material 2, or in the case where insulating resin layers 3 having different thicknesses are to be formed with good accuracy, these insulating sheets 1 can be easily manufactured.
Embodiment 2.
A rotating electric machine 100 according to embodiment 2 will be described. Fig. 10 is a perspective view showing an outline of a stator 20 of a rotating electric machine 100 according to embodiment 2, fig. 11 is a sectional view showing an outline of the stator 20 of the rotating electric machine 100, fig. 12 is a main portion sectional view showing one slot 14 of the stator 20 of the rotating electric machine 100 in an enlarged manner, fig. 13 is a sectional view of the stator 20 cut at a position of a section a-a in fig. 12, and fig. 14 is a sectional view showing a portion shown in B in fig. 12 in an enlarged manner. In these drawings, a rotor provided in the rotating electric machine 100 is omitted. The rotating electric machine 100 according to embodiment 2 is the rotating electric machine 100 having the insulating sheet 1 described in embodiment 1.
A rotating electric machine 100 including a motor, a generator, a compressor, and the like includes an insulating sheet 1 and a stator 20, the insulating sheet 1 is the insulating sheet 1 described in embodiment 1 in which the insulating resin layer 3 has been cured, and the stator 20 includes a cylindrical stator core 12 and a stator coil 11 disposed in a slot 14 formed in the stator core 12 with the insulating sheet 1 obtained by curing the insulating resin layer 3 interposed therebetween. As shown in fig. 11, the slots 14 are formed between the teeth 13 in a predetermined number in the circumferential direction. As shown in fig. 12, the insulating sheet 1 insulates the stator core 12 and the stator coil 11 from each other, and fixes the stator core 12 and the stator coil 11. In the rotating electrical machine 100 using the insulating sheet 1, since the air layer between the stator coil 11 and the stator core 12 is eliminated, the insulating performance of the stator coil 11 is high, and the deterioration of the insulation of the rotating electrical machine 100 is less likely to occur. Further, heat generated from the winding of the stator coil 11 can be efficiently radiated to the stator core 12 via the insulating sheet 1.
In the case where the insulating sheet 1 is previously attached to the stator coil 11 or the stator core 12, the insulating resin layer 3 is selected to have surface tackiness at 25 ℃. When the workability in inserting the stator coil 11 is deteriorated by sticking the insulating sheet 1 in advance, the insulating sheet 1 having no surface tackiness at 25 ℃ is selected.
In the example shown in fig. 12, the insulating sheet 1 in which the insulating resin layers 3 are formed on both surfaces of the substrate 2 is used, but the insulating sheet 1 in which the insulating resin layers 3 are formed on one surface of the substrate 2 may be used. When the insulating resin layer 3 has only one surface, or when the insulating resin layer 3 has no surface tackiness, the insulating sheet 1 may be attached to the stator coil 11 or the stator core 12 using a double-sided adhesive tape or the like.
A manufacturing process of the rotating electric machine 100 will be described. First, the insulating sheet 1 is inserted or bonded into a portion to be a gap between the stator core 12 and the stator coil 11, and the insulating sheet 1 is disposed on the stator 20. Next, the stator core 12 is cylindrically shaped, and the insulating sheet 1 is compressed and fixed to the stator 20. Finally, a curing treatment by heating is performed to cure the insulating resin layer 3 of the insulating sheet 1. Since the insulating sheet 1 contains almost no solvent, it can be cured not only by a general-purpose heating furnace but also by induction heating and electric heating. Further, since energy loss in the curing process is small, the curing time of the insulating resin layer 3 is short, and thus the manufacturing process of the rotating electrical machine 100 can be simplified.
The thickness of the insulating resin layer 3 is formed to fall within a range of 1.1 to 2.0 times the difference between the gap between the stator core 12 (the inner wall of the slot 14) and the stator coil 11 in which the insulating sheet 1 is disposed and the thickness of the base material 2. Therefore, the thickness of the insulating resin layer 3 is reduced by the pressure when the stator core 12 is formed into a cylindrical shape. As shown in fig. 13, the thickness of the insulating sheet 1 inside the slot 14 is smaller than the thickness of the insulating sheet 1 outside the slot 14.
The insulating resin layer 3 can permeate into a minute part of the gap between the stator core 12 and the stator coil 11 and the gap between the stator coils 11 by heating during the curing process, and therefore, an air layer can be eliminated and these gaps can be practically filled. Fig. 14 is a main part sectional view showing an outline of the stator 20 before the insulating sheet 1 is cured. As shown in fig. 14, since the thickness of the insulating resin layer 3 is increased at the bent portion of the insulating sheet 1, even if the gap size between the stator core 12 and the corner 11a of the stator coil 11 varies, the gap can be easily filled. Even if a gap remains in the corner portion 11a, the gap in the corner portion 11a can be filled with the thermosetting resin composition after the curing treatment. The adhesion force between the stator core fixed by the insulating resin layer 3 and the stator coil 11 is 20N/m or more. Since the adhesion force is 20N/m or more, stator coil 11 can be reliably fixed, and thus the mechanical strength of stator 20 can be maintained, and the NVH characteristics of rotating electric machine 100 can be improved.
As described above, since the rotating electric machine 100 according to embodiment 2 includes the insulating sheet 1 and the stator 20 described in embodiment 1, and the stator 20 includes the cylindrical stator core 12 and the stator coil 11 disposed in the slot 14 formed in the stator core 12 via the insulating sheet 1 obtained by curing the insulating resin layer 3, the air layer between the stator coil 11 and the stator core 12 is eliminated, and therefore, the insulation reliability, the heat radiation performance, and the vibration resistance of the rotating electric machine 100 can be improved. Further, since insulation reliability, heat radiation property, and vibration resistance of the rotating electric machine 100 are improved, downsizing and high output of the rotating electric machine 100 can be achieved. In addition, when the adhesion force between the stator core 12 and the stator coil 11 fixed by the insulating resin layer 3 is 20N/m or more, the stator coil 11 can be reliably fixed, and thus the mechanical strength of the stator 20 can be maintained.
Examples
The details of the present invention will be described below with reference to examples and comparative examples, but the present invention is not limited thereto. In examples and comparative examples, the following materials were mixed according to the formulations shown in fig. 15 and 16 to prepare thermosetting resin compositions. FIG. 15 is a table showing the formulation of a thermosetting resin composition of an example, and FIG. 16 is a table showing the formulation of a thermosetting resin composition of a comparative example. A diluent is added to these thermosetting resin compositions to prepare a slurry, and the slurry is applied to a base material 2, and the diluent is evaporated and dried to prepare an insulating resin layer 3 in an uncured or semi-cured state.
< thermosetting resin (A) in solid State >
(1-1) bisphenol A type epoxy resin (epoxy equivalent 2000, softening point 128 ℃ C.)
(1-2) bisphenol A type vinyl ester resin (polymerization average molecular weight 2500, softening point 95 ℃ C.)
< liquid thermosetting resin (B) >
(2-1) bisphenol A type epoxy resin (epoxy equivalent 190)
(2-2) neopentyl glycol diacrylate (viscosity at 25 ℃ C. 6 mPa. multidot.s)
< curing agent >
(3-1) dicyandiamide (reaction initiation temperature 160 ℃ C.)
(3-2) Phenyldimethylamine (having reactivity at ordinary temperature)
(3-3) tert-butylcumyl peroxide (10-hour half-life temperature 119.5 ℃ C.)
< curing accelerators >
(4-1) 1-cyanoethyl-2-phenylimidazole (reaction initiation temperature 125 ℃ C.)
(4-2)1, 8-diazabicyclo (5,4,0) undec-7-ene (reaction initiation temperature 100 ℃ C.)
(4-3) Zinc Octanoate
< thermoplastic resin >
(5-1) phenoxy resin (polymerization average molecular weight 20 ten thousand)
(5-2) polyester resin (polymerization average molecular weight 8 ten thousand)
< inorganic Filler >
(6-1) fused silica (maximum particle diameter 10 μm, minimum particle diameter 1 μm, average particle diameter 3 μm)
(6-2) crystalline silica (maximum particle diameter 30 μm, minimum particle diameter 5 μm, average particle diameter 15 μm)
(6-3) alumina (maximum particle diameter 6 μm, minimum particle diameter 2 μm, average particle diameter 3.5 μm)
(6-4) calcium carbonate (maximum particle diameter 15 μm, minimum particle diameter 3 μm, average particle diameter 6 μm)
(6-5) calcium carbonate (maximum particle diameter 100 μm, minimum particle diameter 10 μm, average particle diameter 50 μm)
< substrate >
(7-1) composite insulating paper: aramid paper/polyimide/aramid paper (thickness 0.15mm, pore size Φ 20 μm, porosity 50%)
(7-2) composite insulating film: polyphenylene sulfide/polyethylene terephthalate/polyphenylene sulfide (thickness 0.17mm, interlayer adhesive, pore size 50 μm □, porosity 65%)
(7-3) nanofiber nonwoven fabric: polyetheretherketone (thickness: 0.075mm, void size 3-20 μm, void fraction 70%)
(7-4) mesh cloth: alumina (thickness: 0.15mm, mesh size 100 μm, mesh rate 65%)
(7-5) aramid paper (thickness 0.18mm)
(7-6) insulating film: polyethylene terephthalate (thickness 0.1mm, pore size phi 0.8 mu m, porosity 70%)
(7-7) nonwoven Fabric: polyester (thickness: 0.12mm, void size 0.5 to 2 μm, void fraction 15%)
(7-8) mesh cloth: polyether Ether ketone (thickness: 0.07mm, mesh size 1 μm, mesh ratio 1.5%)
< evaluation items of examples and comparative examples >
Using the raw materials described in embodiment 1, 5 kinds of insulating sheets 1 shown in the example of fig. 15 were prepared according to the formulation set forth in embodiment 1. On the other hand, in the 4 types of insulating sheets 1 shown in the comparative example of fig. 16, the formulation of the raw material, the selection of the substrate 2, the coating conditions of the insulating resin layer 3 on the substrate 2, and the like do not meet the present invention, and the insulating sheet 1 shown in the present invention cannot be produced. The insulating sheet 1 and the insulating resin layer 3 (before curing) shown in fig. 15 and 16 were evaluated for surface smoothness, flexibility, compressibility, thermal conductivity, adhesiveness, cracks, nonvolatile components, gelation time, storage shear modulus, and complex viscosity of the insulating resin layer 3. Further, the insulating resin layer 3 after the curing treatment was evaluated for the adhesive strength and dielectric breakdown voltage. The evaluation results of the examples and comparative examples are shown in fig. 17 and fig. 18, respectively.
The contents of the evaluation will be described. The surface smoothness was judged by whether or not the in-plane distribution of the thickness of the insulating resin layer 3 was within. + -. 30% of the average value (good:. + -. 30%, poor:. + -. 30%). The measurement of flexibility and compressibility was performed 2 times, respectively immediately after the preparation of the insulating sheet 1 and after 30 days of storage at 40 ℃, to confirm the usable time of the insulating sheet 1. Flexibility was evaluated by the presence or absence of cracking or chipping when the insulating sheet 1 was bent 180 degrees at 25 ℃ (good: no occurrence, and good: no occurrence). The compressibility of the insulating resin layer 3 was calculated from the decrease in thickness of the insulating resin layer 3 when the insulating sheet 1 was placed on a rolled steel sheet and a pressure of 25MPa was applied at 25 ℃. Evaluation of compression ratio was judged by whether or not the compression ratio was 10% or more (good: 10% or more, x: less than 10%).
The thermal conductivity of the insulating sheet 1 was evaluated by calculating the value of (thermal conductivity of the insulating sheet 1)/(thermal conductivity of the insulating resin layer 3) to grasp whether or not the thermal conductivity of the insulating resin layer 3 is reflected on the thermal conductivity of the insulating sheet 1. By using the substrate 2 having the through holes 4 formed of voids, or meshes, the thermosetting resin composition is filled in the through holes 4, so that the heat radiation effect of the insulating resin layer 3 can be reflected on the insulating sheet 1 regardless of the material of the substrate 2. The thermal conductivity of the entire insulating sheet 1 composed of the insulating resin layer 3 and the substrate 2 is described as a ratio to the thermal conductivity of the insulating resin layer 3 alone. The closer the ratio is to 1, the more the thermal conductivity of the insulating resin layer 3 is reflected on the thermal conductivity of the insulating sheet 1. The ratio allows the influence of heat dissipation inhibition by the base material 2 to be grasped.
The adhesiveness was evaluated by placing the insulating sheet 1 on a rolled steel sheet, and whether or not the sheet was adhered when pressed at 40 ℃ under a pressure of 2MPa, 2 times, immediately after the production and 30 days after the storage at 40 ℃. In addition, since adhesiveness is preferable and non-adhesiveness is preferable depending on the use of the insulating sheet 1, it cannot be said that adhesiveness is better in any way. However, since it is not desirable that the tackiness change immediately after the production and after 30 days, the change in the presence or absence of tackiness was evaluated.
The cracking was confirmed to determine the occurrence of cracking (Japanese patent: クレージング) in order to examine the effect on the coating film of the enamel wire. An enameled wire (phi 1.0mm) having a polyester imide/polyamide imide coating was stretched by 5% to prepare a test piece bent in a U-shape, and an insulating sheet was attached to the surface of the coating at room temperature for 1 minute and then peeled off. When the insulating resin layer 3 has no surface tackiness and cannot be adhered to the enamel wire, the enamel wire is brought into contact with the insulating sheet 1 by fixing the insulating sheet 1 with a clip. After the peeling, an optical microscope observation and a pinhole test were performed to evaluate the presence or absence of the crack phenomenon. In the pinhole test, a test piece of a predetermined length (about 5m) was immersed in saline water based on JISC3003, and a dc voltage was applied at 12V for 1 minute with the liquid as a positive electrode and the test piece as a negative electrode to examine the number of pinholes generated at this time. In addition, the test piece cured at 150 ℃ for 1hr after the application was also observed by an optical microscope to see whether or not cracks or pinholes were generated on the film surface. As a result, it was judged that no crack or pinhole was generated and the insulation breakdown voltage was not lowered, and it was judged that no crack was generated and that crack was generated (good: no crack, good: crack).
The nonvolatile content was determined by calculating the change in weight of the insulating resin layer 3 before and after curing, and determining whether the weight after curing was 97% or more (o: 97% or more, x: less than 97%) relative to the weight before curing. The gelation time is measured by collecting the insulating resin layer 3 and measuring the gelation time at 150 ℃ by a hot plate method. The storage shear modulus and complex viscosity were measured by a dynamic viscoelasticity evaluation at a temperature rise rate of 5 ℃/min from room temperature using an insulating resin layer 3 having a thickness of 100 to 300 μm with a parallel plate jig. For storage shear modulus, pass whether at 25 ℃ 1.0X 103Pa～5.0×104Pa, the lowest value of which is within the range of 80-150 ℃ and is within the range of 10 Pa-2.0 x 103And Pa (good: in range, poor: out of range). For complex viscosity, the viscosity is determined by whether the temperature is 6.0X 10 at 25 DEG C2Pa·s～1.0×104Pa · s range, and whether the lowest value is in the range of 80 ℃ to 150 ℃ or not, 5.0X 102Pa s or less (good: in range, poor: out of range).
The adhesion strength was evaluated by manufacturing an adhesion test piece and using a tensile tester. The adhesion test piece was produced by pressure-bonding the insulating sheet 1 to an electromagnetic steel sheet subjected to the acetone degreasing surface treatment and curing at 150 ℃ for 1 hour. The tensile test was carried out at 25 ℃ under conditions of a peel angle of 180 degrees and a tensile speed of 10mm/min, and evaluated according to the criterion of an adhesive strength of 10N/m (O: an adhesive strength of 10N/m or more, X: an adhesive strength of less than 10N/m).
The dielectric breakdown voltage was evaluated by applying an insulating resin layer 3 to one side of a steel sheet, curing the sheet at 150 ℃ for 1 hour, applying a voltage at a constant voltage rise of 0.5 kV/sec in oil using a dielectric breakdown tester to obtain a test piece, and measuring the dielectric breakdown voltage using a standard for evaluation of the dielectric breakdown voltage of 8kV (good: the dielectric breakdown voltage is 8kV or more, and x: the dielectric breakdown voltage is less than 8 kV).
< evaluation results of examples and comparative examples >
First, the evaluation results of the examples will be described with reference to fig. 17. The 5 kinds of insulating sheets 1 shown in the example of fig. 17 are excellent in both flexibility and viscoelastic properties (storage shear modulus, complex viscosity), and have a compressibility of 10% or more. Therefore, when the insulating sheet 1 is disposed in the gap between the stator core 12 and the stator coil 11 of the rotating electric machine 100, the thickness of the insulating resin layer 3 is reduced by the pressure when the stator core 12 is formed into a cylindrical shape, and the insulating resin layer 3 flows and penetrates into a fine portion of the gap when heated. Further, since flexibility and compressibility were not changed after 30 days of storage at 40 ℃, the reaction proceeded slowly at room temperature, and the usable time of the insulating sheet 1 was long. In addition, high bonding strength and dielectric breakdown voltage were obtained.
Further, the thermal conductivity of the insulating sheet 1 was secured to be 0.85 times or more the thermal conductivity of the insulating resin layer 3, and it was found that by using the base material 2 having the through-holes 4, the insulating sheet 1 was less susceptible to the thermal resistance of the base material 2. In addition, with example 4, by using alumina mesh cloth having a higher thermal conductivity than the insulating resin layer 3 as the base material 2, higher thermal conductivity was ensured as the insulating sheet 1. Example 5 is an insulating sheet 1 using the formulation of example 1, containing no inorganic filler material. The resin component in example 5 was 100%, and thus the flexibility and adhesiveness were more excellent than those in example 1. On the other hand, the insulating resin layer 3 has a low thermal conductivity, which is about the same as that of the base material 2, and therefore the thermal conductivity of the single insulating sheet 1 is lower than that of example 1.
Next, the evaluation results of the comparative example will be described with reference to fig. 18. The formulation of the raw materials of the 4 kinds of insulating sheets 1 of the comparative examples, the selection of the substrate 2, the coating conditions of the insulating resin layer 3 on the substrate 2, and the like do not conform to the present invention, and thus the desired characteristics of the insulating sheet 1 cannot be obtained. Comparative example 1 is the formulation of example 1, using a substrate 2 without through-holes 4 formed by voids, voids or meshes. In comparative examples 2 to 4, a substrate 2 having through-holes 4 smaller in particle size than the inorganic filler contained in the thermosetting resin composition was used.
The raw material of the insulating resin layer 3 of comparative example 1 is the same in composition as that of example 1, and therefore the characteristics of the insulating resin layer 3 of comparative example 1 are the same as those of example 1. Therefore, the insulating sheet 1 of comparative example 1 has the same characteristics as example 1 except for the thermal conductivity. In comparative example 1, the thermal conductivity of the insulating sheet 1 was much lower than that of the insulating resin layer 3. By using the substrate 2 having no through-holes 4, the substrate 2 becomes thermal resistance, and the thermal conductivity of the insulating resin layer 3 cannot be reflected on the insulating sheet 1.
The raw material of the insulating resin layer 3 of comparative example 2 was the same in composition as in example 2. However, since the thermosetting resin composition is excessively dried after being applied to the substrate 2, the insulating resin layer 3 is close to a completely cured state and thus has no flexibility. Therefore, the insulating sheet 1 has a very low compression ratio, and cracks and separation occur in the insulating resin layer 3 due to bending, so that workability of the insulating sheet 1 is deteriorated. An insulating film having pores with a size of Φ 0.8 μm, which forms the through-holes 4, is used as the substrate 2, and the size is smaller than the particle size (maximum particle size 30 μm, minimum particle size 5 μm, average particle size 15 μm) of the inorganic filler contained in the insulating resin layer 3. Therefore, the thermosetting resin composition cannot permeate into the through-holes 4, and an air layer remains in the substrate 2, which significantly reduces the thermal conductivity of the insulating sheet 1.
Comparative example 3 is the formulation of example 3, with only the curing agent being different. Comparative example 3 contains a curing agent having reactivity at ordinary temperature. The insulating sheet 1 of comparative example 3 had a problem in working time because the reaction of the insulating resin layer 3 proceeded in a state of standing at room temperature and the physical properties of the insulating resin layer 3 changed with time. After 30 days, flexibility and adhesiveness were lost and the compressibility was reduced. Since the curing is performed at normal temperature, the fluidity during the heat curing is low, and the permeability into the minute gap is not obtained, and the adhesion to the member is poor. Further, the insulating resin layer 3 is cracked or peeled off by bending, and workability of the insulating sheet 1 is deteriorated. A nonwoven fabric having voids, wherein the size of the voids forming the through-holes 4 is 0.5 to 2 μm and is smaller than the particle size (maximum particle size 6 μm, minimum particle size 2 μm, average particle size 3.5 μm) of the filler of the insulating resin layer 3, is used as the base material 2. Therefore, the thermosetting resin composition cannot penetrate into the through-holes 4, and an air layer remains in the base material 2, which significantly reduces the thermal conductivity of the insulating sheet 1.
Comparative example 4 is the formulation of example 4, and the type and amount of inorganic filler are different. In comparative example 4, 73 vol% of an inorganic filler having a maximum particle diameter of 100 μm, a minimum particle diameter of 10 μm, and an average particle diameter of 50 μm was excessively filled. Comparative example 4 is an insulating sheet 1 having a total thickness of 220 μm in which insulating resin layers 3 having a thickness of 75 μm were formed on both sides of a substrate 2 having a thickness of 70 μm. Since the maximum particle size of the inorganic filler is larger than the thickness of the insulating resin layer 3, the inorganic filler protrudes from the surface of the insulating resin layer 3, and thus the surface smoothness is low. In addition, since the inorganic filler is excessively doped, there is no flexibility and the insulating resin layer 3 cannot be compressed. In addition, the storage shear modulus and the complex viscosity do not fall within the desired ranges. Therefore, the insulating sheet 1 of comparative example 4 cannot be inserted into the gap (240 μm) between the stator core 12 and the stator coil 11. Further, since the resin component ratio of the insulating resin layer 3 is small, the adhesion between the stator core 12 and the stator coil 11 and the insulating sheet 1 is poor, and a desired adhesive strength cannot be obtained. A mesh fabric having meshes is used as the substrate 2, wherein the size of the meshes forming the through holes 4 is 1 μm and is smaller than the particle diameter (maximum particle diameter 100 μm, minimum particle diameter 10 μm, average particle diameter 50 μm) of the inorganic filler of the insulating resin layer 3. Therefore, the thermosetting resin composition cannot penetrate into the through-holes 4, and an air layer remains in the base material 2, which significantly reduces the thermal conductivity of the insulating sheet 1.
As described above, the examples were good in all evaluation items. However, the comparative example performed poorly on some evaluation items. By preparing the insulating sheet 1 according to the formulation set forth in embodiment 1 from the raw materials described in embodiment 1, the insulating sheet 1 having the characteristic that the thermosetting resin flows when heated and penetrates into the minute portions of the gaps of the member to be insulated can be obtained.
Various exemplary embodiments and examples are described in the present application, but various features, forms, and functions described in one or more embodiments are not limited to only specific embodiments, and may be applied to the embodiments alone or in various combinations.
Therefore, countless modifications not exemplified are also considered to fall within the technical scope disclosed in the present specification. For example, the case where at least one constituent element is deformed, the case where at least one constituent element is added, or the case where at least one constituent element is omitted is included, and the case where at least one constituent element is extracted and combined with the constituent elements of other embodiments is also included.
Description of the symbols
1 insulating sheet, 2 base material, 2a sheet, 3 insulating resin layer, 3a hole insulating resin, 4 through holes, 5 adhesive, 10 composite insulating sheet, 11 stator coil, 11a corner, 12 stator core, 13 tooth, 14 slot, 20 stator, 100 rotating electrical machine.

Claims (18)

1. An insulating sheet comprising:
a sheet-like substrate having voids, voids or meshes, and
an insulating resin layer made of a thermosetting resin composition provided on one or both surfaces of the base material;
the base material is formed by a single-layer sheet of any one of insulating paper, an insulating film, non-woven fabric and mesh fabric or a laminated sheet formed by laminating a plurality of sheets selected from the insulating paper, the insulating film, the non-woven fabric and the mesh fabric;
the insulating resin layer is in an uncured or semi-cured state;
the thermosetting resin composition has a first thermosetting resin which is solid at 25 ℃, a second thermosetting resin which is liquid at 25 ℃, and a latent curing agent which is reactive inert at 60 ℃ or lower;
the mass part of the first thermosetting resin is in the range of 10 to 90 parts by mass, assuming that the total mass of the first thermosetting resin and the second thermosetting resin is 100 parts by mass.
2. The insulation sheet of claim 1,
the thermosetting resin composition has a plurality of inorganic fillers in a granular form;
the inorganic fillers have a maximum particle diameter smaller than the thickness of the insulating resin layer, and an average particle diameter smaller than 0.5 times the thickness of the insulating resin layer.
3. The insulation sheet of claim 2,
the size of the pores, voids, and meshes in a direction parallel to the surface of the base material is larger than the minimum particle diameter of the plurality of inorganic fillers;
the porosity of the pores, the porosity of the voids, and the mesh opening ratio of the mesh are in the range of 20% to 95%.
4. The insulation sheet according to any one of claims 1 to 3, wherein the material of the base is an insulation resin material made of engineering plastic or super engineering plastic, an inorganic insulation material made of silica, alumina, or glass, or a material containing the fibrous insulation resin material or the fibrous inorganic insulation material.
5. The insulation sheet according to any one of claims 1 to 4,
the substrate is the laminated sheet;
the base material is formed by laminating either or both of the insulating paper and the insulating film.
6. The insulation sheet according to any one of claims 1 to 5,
the substrate is the laminated sheet;
the substrate includes a plurality of the sheets stacked with the insulating resin layer or the adhesive interposed therebetween.
7. The insulation sheet according to any one of claims 1 to 6, wherein said first thermosetting resin and said second thermosetting resin have at least one of an epoxy resin, a phenol resin, and an unsaturated polyester resin.
8. An insulating sheet material as claimed in any of claims 1 to 6, characterised in that said first thermosetting resin is an epoxy resin having a softening point in the range 50 ℃ to 160 ℃.
9. The insulation sheet according to any one of claims 1 to 8, wherein the latent curing agent is any one of a boron trifluoride-amine complex, dicyandiamide, and organic acid hydrazide.
10. Insulating sheet material according to any one of claims 1 to 9,
the thermosetting resin composition has a thermoplastic resin with a weight average molecular weight in the range of 10,000-100,000;
the thermoplastic resin is in the range of 1 to 100 parts by mass, assuming that the total mass of the first thermosetting resin and the second thermosetting resin is 100 parts by mass.
11. The insulation sheet according to any one of claims 1 to 10, wherein a nonvolatile content of said insulation resin layer is 97 parts by mass or more with respect to 100 parts by mass of the total mass of said thermosetting resin composition.
12. Insulating sheet material according to any of claims 1 to 11,
the insulating resin layer has a storage shear modulus of 1.0 × 10 at 25 deg.C3Pa～5.0×104Pa range;
the lowest value of the storage shear modulus is within the range of 80-150 ℃ and between 10Pa and 2.0 multiplied by 103Pa, in the range of Pa.
13. Insulating sheet material according to any one of claims 1 to 12,
the insulating resin layer has a complex viscosity of 6.0 × 10 at 25 deg.C2Pa·s～1.0×104Pa · s range;
the lowest value of the complex viscosity is 5.0 x 10 in the range of 80 ℃ to 150 DEG C2Pa · s or less.
14. The insulation sheet according to any one of claims 1 to 13, wherein a thickness of the insulation resin layer is formed to fall within a range of 1.1 to 2.0 times a difference between a gap in which the insulation sheet is disposed and a thickness of the base material.
15. A rotating electrical machine comprising:
the insulating sheet as claimed in any one of claims 1 to 14, in which the insulating resin layer is cured, and
a stator including a cylindrical stator core and a stator coil arranged in a slot formed in the stator core via the insulating sheet obtained by curing the insulating resin layer;
the insulating sheet insulates between the stator core and the stator coil, and fixes the stator core and the stator coil.
16. The rotating electric machine according to claim 15, wherein the adhesion force between the stator core and the stator coil fixed by the insulating resin layer is 20N/m or more.
17. A method for producing an insulating sheet comprising a sheet-like base material having pores, voids or meshes and an insulating resin layer comprising a thermosetting resin composition provided on one or both surfaces of the base material, the method comprising:
a first step of stirring and mixing a first thermosetting resin which is solid at 25 ℃, a second thermosetting resin which is liquid at 25 ℃, a latent curing agent which is reactive at 60 ℃ or lower, a plurality of particulate inorganic fillers having a maximum particle diameter smaller than the thickness of the insulating resin layer and an average particle diameter smaller than 0.5 times the thickness of the insulating resin layer, and a diluent to prepare a slurry of the thermosetting resin composition; and
a second step of applying the slurry to one or both surfaces of the base material formed of a single-layer sheet of any one of insulating paper, an insulating film, a nonwoven fabric and a mesh fabric, or a laminated sheet in which a plurality of sheets selected from the insulating paper, the insulating film, the nonwoven fabric and the mesh fabric are laminated, and then drying the slurry to an uncured or semi-cured state;
the preparation temperature of the slurry is normal temperature;
in the thermosetting resin composition in the first step, the mass part of the first thermosetting resin is in the range of 10 to 90 parts by mass, assuming that the total mass of the first thermosetting resin and the second thermosetting resin is 100 parts by mass.
18. A method for producing an insulating sheet comprising a sheet-like base material having pores, voids or meshes and an insulating resin layer comprising a thermosetting resin composition provided on one or both surfaces of the base material, the method comprising:
a first step of stirring and mixing a first thermosetting resin which is solid at 25 ℃, a second thermosetting resin which is liquid at 25 ℃, a latent curing agent which is reactive at 60 ℃ or lower, a plurality of particulate inorganic fillers having a maximum particle diameter smaller than the thickness of the insulating resin layer and an average particle diameter smaller than 0.5 times the thickness of the insulating resin layer, and a diluent to prepare a slurry of the thermosetting resin composition;
a second step of drying the slurry to an uncured or semi-cured state after applying the slurry to release paper or a release film; and
a third step of bonding the slurry dried in the second step to one or both surfaces of the base material formed of a single-layer sheet of any one of insulating paper, an insulating film, a nonwoven fabric and a mesh fabric or a laminated sheet formed by laminating a plurality of sheets selected from the insulating paper, the insulating film, the nonwoven fabric and the mesh fabric;
the preparation temperature of the slurry is normal temperature;
in the thermosetting resin composition in the first step, the mass part of the first thermosetting resin is in the range of 10 to 90 parts by mass, assuming that the total mass of the first thermosetting resin and the second thermosetting resin is 100 parts by mass.
CN202111374190.XA 2020-11-25 2021-11-19 Insulating sheet, method for producing same, and rotating electrical machine Pending CN114552840A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2020194882A JP7058704B1 (en) 2020-11-25 2020-11-25 Insulation sheet and its manufacturing method, and rotary electric machine
JP2020-194882 2020-11-25

Publications (1)

Publication Number Publication Date
CN114552840A true CN114552840A (en) 2022-05-27

Family

ID=81291892

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111374190.XA Pending CN114552840A (en) 2020-11-25 2021-11-19 Insulating sheet, method for producing same, and rotating electrical machine

Country Status (2)

Country Link
JP (1) JP7058704B1 (en)
CN (1) CN114552840A (en)

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56159011A (en) * 1980-05-09 1981-12-08 Mitsubishi Electric Corp Electrically insulating tape
JP2732822B2 (en) * 1995-12-28 1998-03-30 デュポン帝人アドバンスドペーパー株式会社 Composite sheet and method for producing the same
JPH11299156A (en) * 1998-04-10 1999-10-29 Hitachi Ltd Electric rotating machine and insulating sheet for electrical machinery and apparatus
JP5956314B2 (en) * 2012-11-19 2016-07-27 日東電工株式会社 Electric insulating resin sheet for motor
JP5919185B2 (en) * 2012-12-17 2016-05-18 日東電工株式会社 Polyetherimide porous body and method for producing the same
JP2015074710A (en) * 2013-10-08 2015-04-20 株式会社日立製作所 Resin composition, method for producing resin composition, resin cured matter, and electrical equipment, electric wire, resin film laminated body and structure using the resin cured matter
JP6327980B2 (en) * 2014-07-04 2018-05-23 菱電化成株式会社 Manufacturing method of rotating electrical machine
JP6914309B2 (en) * 2019-10-31 2021-08-04 三菱電機株式会社 Sheet type insulating varnish and its manufacturing method, electrical equipment, and rotary electric machine
JP6824372B1 (en) * 2019-12-17 2021-02-03 三菱電機株式会社 Insulation sheet and its manufacturing method, and rotary electric machine

Also Published As

Publication number Publication date
JP2022083529A (en) 2022-06-06
JP7058704B1 (en) 2022-04-22

Similar Documents

Publication Publication Date Title
CN112992406B (en) Insulating sheet, method for producing same, and rotating electrical machine
CN112745742B (en) Thermosetting resin composition, sheet-type insulating varnish, method for producing same, electrical device, and rotating electrical machine
JP4691365B2 (en) Adhesive composition for semiconductor device and adhesive sheet for semiconductor device
JP4495772B1 (en) Insulating sheet and laminated structure
SG173402A1 (en) Resin composition, prepreg, laminate, and wiring board
WO2008145190A1 (en) Laminate for electrical machines
JP5584657B2 (en) Self-healing laminated structure and self-bonding insulated wire
WO2018168715A1 (en) Resin composition and resin sheet
KR20150132010A (en) Inorganic filler-containing epoxy resin cured product and laminate including the same
CN115506177B (en) Insulating sheet, method for manufacturing same, and rotating electrical machine
US20220251335A1 (en) Resin composition, cured product, composite molded product, semiconductor device
JP2009224109A (en) Insulation sheet and laminated structural body
JP2009231249A (en) Insulation sheet and laminated structural body
JP4691401B2 (en) Adhesive composition for semiconductor device and adhesive sheet for semiconductor device
CN114552840A (en) Insulating sheet, method for producing same, and rotating electrical machine
JP2008189815A (en) Dispersant, filler, heat-conductive resin composition and heat-conductive sheet
JP7383971B2 (en) Resin compositions, cured resin products and composite molded bodies
US20210206943A1 (en) Resin composition, resin cured product, and composite molded body
WO2023162068A1 (en) Sheet-type insulating varnish, method for manufacturing same, electric apparatus, and rotary electric machine
WO2022176071A1 (en) Insulating sheet, stator and method for producing stator
WO2019088079A1 (en) Laminate film and manufacturing method of laminate film
JP5449306B2 (en) Dispersant, heat conductive resin composition and heat conductive sheet
TW202402964A (en) Thermosetting resin composition, thermally conductive resin sheet, heat-dissipating layered product, heat-dissipating circuit board, semiconductor device and power module
TW202244184A (en) Resin composition, adhesive layer and adhesive sheet, and method for producing adhesive sheet
US20240010814A1 (en) Resin composition, cured product sheet, composite molded body, and semiconductor device

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination