CN111712380B

CN111712380B - Resin structure and method for producing resin structure

Info

Publication number: CN111712380B
Application number: CN201980012833.0A
Authority: CN
Inventors: 森冈聪子; 箕浦洁; 和田惠太
Original assignee: Toray Industries Inc
Current assignee: Toray Industries Inc
Priority date: 2018-02-16
Filing date: 2019-02-06
Publication date: 2022-08-30
Anticipated expiration: 2039-02-06
Also published as: JP7234917B2; JPWO2019159792A1; KR20200123087A; TW201945170A; CN111712380A; WO2019159792A1

Abstract

The present invention provides a resin structure having excellent liquid repellency and excellent durability such that the liquid repellency is not reduced by external conditions. The resin structure of the present invention is a liquid-repellent structure including a base layer and a fiber layer made of a plurality of fibers, wherein the fiber layer is made up of substantially vertical portions and substantially parallel portions, the substantially vertical portions are present on a side close to the base layer, the fibers in the substantially vertical portions extend in a state substantially perpendicular to a surface of the base layer, the substantially parallel portions are present on a side away from the base layer, the fibers in the substantially parallel portions extend in a state substantially parallel to the surface of the base layer, and all of the fibers constituting the fiber layer are bonded to the surface of the base layer and extend from the surface of the base layer.

Description

Resin structure and method for producing resin structure

Technical Field

The present invention relates to a resin structure having a fiber layer composed of a plurality of fibers on the surface thereof to exhibit a liquid repellent effect, and a method for producing the resin structure.

Background

Conventionally, as a method for exhibiting a liquid repellent effect on the surface of a structure, a method of applying a resin having low surface energy such as a fluorine-based polymer to the structure has been widely used. However, in the case of only coating, the liquid repellency is limited, and the expected liquid repellency cannot be obtained. Therefore, a method of adding a fine structure to the surface of a structure to obtain a liquid repellency at a level equal to or higher than the liquid repellency obtained by the coating method has been proposed (patent document 1).

Further, as a fine structure exhibiting a liquid repellent effect, a composite shape in which a projection having anisotropy is directed in a direction other than a direction perpendicular to the surface of a structure body and a convex portion having a concavo-convex shape has a fiber shape has been proposed (patent documents 2 and 3).

As a method for improving the water-and oil-slipperiness, a method has been proposed in which a wet synovial fluid is contained in a mesh structure interlaced in three-dimensional directions (patent document 4).

Documents of the prior art

Patent literature

Patent document 1: japanese patent laid-open publication No. 2004-170935

Patent document 2: international publication No. 2015/159825

Patent document 3: japanese patent laid-open publication No. 2016-155258

Patent document 4: japanese patent laid-open publication No. 2016-11375

Disclosure of Invention

Problems to be solved by the invention

However, the techniques described in patent documents 1 to 4 have a problem that the liquid repellency is insufficient, liquid droplets remain in a state of being adhered to a film as a structure, and a desired liquid repellency effect cannot be obtained, or a problem in durability is caused such that the shape of a fine structure is broken by an external force or the like to reduce the liquid repellency.

In addition, in the technique described in patent document 4, since it is necessary to change the lubricating liquid depending on the type of liquid, there is a problem that the type of liquid is limited and the liquid repellency is low.

Means for solving the problems

(1) The resin structure of the present invention for solving the above problems is a resin structure comprising a base layer and a fiber layer composed of a plurality of fibers,

the fiber layer is composed of a substantially vertical portion and a substantially parallel portion, the substantially vertical portion is present on a side close to the base layer, the fibers in the substantially vertical portion extend substantially perpendicularly to a surface of the base layer, the substantially parallel portion is present on a side away from the base layer, and the fibers in the substantially parallel portion extend substantially parallel to the surface of the base layer,

all of the fibers constituting the fiber layer are bonded to the surface of the base layer and extend from the surface of the base layer.

(2) Further, the resin structure of the present invention for solving the above problems is a resin structure comprising a base layer and a fiber layer composed of a plurality of fibers,

fibers constituting the fiber layer are bonded to and extend from the surface of the base layer, the area of the portion of the surface of the base layer to which the fibers are bonded is 5 to 40% of the surface area of the surface of the base layer on which the fiber layer is formed,

when the resin structure is observed from the surface on the fiber side, the ratio of the area occupied by the fibers is 80% or more of the surface area of the base layer.

(3) A manufacturing method of the present invention for manufacturing a resin structure that solves the above problems is a method for manufacturing a resin structure, the manufacturing method including:

a step of disposing a resin composition on a surface of a mold having a plurality of fine holes formed on the surface thereof,

a step of heating and pressing the mold and the resin composition to press a part of the resin composition into the hole,

a step of cooling the resin composition in a state where a part of the resin composition is present in the hole, and

a step of forming a resin structure composed of a fiber layer composed of the fibers and a base layer not containing the fibers by drawing the resin composition present in the holes and simultaneously peeling the resin composition from the die to form a plurality of fibers in which the resin composition is drawn,

the respective steps are sequentially performed to form a resin structure in which the fiber layer is composed of substantially vertical portions and substantially parallel portions, the substantially vertical portions are present on a side close to the base layer, the fibers in the substantially vertical portions extend substantially perpendicularly to the surface of the base layer, the substantially parallel portions are present on a side away from the base layer, and the fibers in the substantially parallel portions extend substantially parallel to the surface of the base layer.

(4) A manufacturing method of the present invention for manufacturing a resin structure that solves the above problems is a method for manufacturing a resin structure, the manufacturing method including the steps of:

a step of pressing the mold and the resin composition while heating the mold and pressing a part of the resin composition into the hole,

a step of cooling the resin composition in a state where a part of the resin composition is present in the hole,

a step of forming a resin structure composed of a fiber layer composed of the fibers and a base layer not containing the fibers by forming a plurality of fibers obtained by drawing the resin composition while drawing the resin composition present in the holes and peeling the resin composition from the die, and a method for manufacturing a resin structure

A step of applying pressure to the resin structure from a direction substantially perpendicular to the fiber layer so that the fiber layer is composed of substantially perpendicular portions and substantially parallel portions, the substantially perpendicular portions being present on a side close to the base layer, the fibers in the substantially perpendicular portions extending substantially perpendicular to a surface of the base layer, the substantially parallel portions being present on a side away from the base layer, the fibers in the substantially parallel portions extending substantially parallel to the surface of the base layer,

in the above production method, the above steps are performed in this order.

ADVANTAGEOUS EFFECTS OF INVENTION

In the resin structure of the present invention, the fiber layer composed of a plurality of fibers forms an air layer between the liquid droplets and the base layer when the liquid droplets are attached, so that the contact area between the liquid droplets and the air is increased, and the liquid-repellent function can be significantly improved by the surface tension of the liquid droplets. Further, since the tips of the fibers extend substantially parallel to the surface of the base layer, the liquid repellency can be maintained even when the shape is deformed by an external force.

Further, even when liquid intrudes between the fibers, the intrusion of liquid can be suppressed by the air layer formed by the fibers on the side close to the base layer extending substantially vertically, and liquid repellency can be maintained. Further, since the liquid is repelled by the tips of the fibers on the side away from the base layer, the liquid is less likely to come into contact with the base layer due to dripping, and the liquid repellency is suppressed from decreasing, so that the liquid repellency and the stain-proofing effect having high effects can be exhibited more stably.

Drawings

FIG. 1 is a schematic cross-sectional view of a film as a resin structure of the present invention.

Fig. 2 is a schematic perspective view of a film as a resin structure of the present invention.

FIG. 3 is a schematic surface view of a film as a resin structure of the present invention.

FIG. 4 is a schematic view showing the structure of the base layer surface of a film as a resin structure of the present invention.

FIG. 5 is a schematic cross-sectional view showing an example of an apparatus for producing a film as a resin structure of the present invention.

Fig. 6 is a schematic plan view of a peeling unit in an apparatus for manufacturing a film as a resin structure of the present invention from the width direction of the film.

FIG. 7 is a schematic cross-sectional view showing another example of an apparatus for producing a film as a resin structure of the present invention.

Fig. 8 is a cross-sectional photograph taken with a scanning electron microscope, a power spectrum obtained by fourier transform, and an example of an angle distribution pattern of a fiber, of the resin structure of the present invention used for determining a substantially vertical portion and a substantially parallel portion of a fiber layer.

FIG. 9 is a surface photograph of a resin structure (thin film) of example 1 taken by a scanning electron microscope.

FIG. 10 is a photograph of a cross section of a resin structure (thin film) of example 1 taken with a scanning electron microscope.

FIG. 11 is a surface photograph of a resin structure (thin film) of example 2 taken by a scanning electron microscope.

FIG. 12 is a photograph of a cross section of the resin structure (thin film) of example 2 taken with a scanning electron microscope.

FIG. 13 is a surface photograph of a resin structure (thin film) of example 3 taken by a scanning electron microscope.

FIG. 14 is a photograph of a cross-section of a resin structure (thin film) of example 3 taken by a scanning electron microscope.

FIG. 15 is a surface photograph of the resin structure (thin film) of comparative example 1 taken by a scanning electron microscope.

FIG. 16 is a photograph of a cross-section of a resin structure (thin film) of comparative example 1 taken by a scanning electron microscope.

Detailed Description

[ resin Structure ]

The resin structure of the present invention is a structure including a base layer and a fiber layer made of a plurality of fibers, wherein the fiber layer is made up of a substantially vertical portion and a substantially parallel portion, the substantially vertical portion is present on a side close to the base layer, the fibers in the substantially vertical portion extend substantially perpendicularly to a surface of the base layer, the substantially parallel portion is present on a side away from the base layer, the fibers in the substantially parallel portion extend substantially parallel to the surface of the base layer, and all of the fibers constituting the fiber layer are bonded to the surface of the base layer and extend from the surface of the base layer.

The resin structure of the present invention is a resin structure including a base layer and a fiber layer composed of a plurality of fibers, the fibers constituting the fiber layer being bonded to the surface of the base layer and extending from the surface of the base layer, the area of a portion of the surface of the base layer where the fibers are bonded being 5 to 40% of the surface area of the surface of the base layer where the fiber layer is formed, and the ratio of the area occupied by the fibers when the resin structure is viewed from the surface on the fiber side being 80% or more of the surface area of the base layer.

An embodiment of a resin structure having fibers on the surface according to the present invention will be described with reference to the drawings. Fig. 1 is a schematic cross-sectional view of a film as a resin structure of the present invention, and fig. 2 is a schematic perspective view.

The resin structure 10 is composed of a base layer 11 and a fiber layer 14 composed of a plurality of fibers 13. The fibers 13 present on the surface 12 of the base layer 11 are bonded to the surface 12 of the base layer 11 and extend from the surface 12. Here, the fibers 13 mean portions having a shape convex with respect to the surface 12 of the base layer 11 as shown in fig. 1 of the schematic cross-sectional view, and the fibers 13 are preferably present independently and discretely. The shape of the fiber 13 may be any shape, but is preferably tapered, and a bulge may be present at the tip of the fiber 13. The fiber layer 14 composed of the plurality of fibers 13 is composed of a substantially vertical portion 15 and a substantially parallel portion 16, the substantially vertical portion 15 is present on the side close to the surface 12 of the base layer 11, the fibers 13 in the substantially vertical portion extend in a state substantially perpendicular to the surface 12 of the base layer 11, the substantially parallel portion 16 is present on the side far from the surface 12 of the base layer 11, and the fibers 13 in the substantially parallel portion extend in a state substantially parallel to the surface 12 of the base layer 11. Note that the phrase "the fibers 13 are substantially perpendicular to the surface 12 of the base layer 11" means that the substantially perpendicular portions 15 extend at an angle of 60 ° to 120 ° with respect to the surface 12 of the base layer 11, and the phrase "the fibers 13 are substantially parallel to the surface 12 of the base layer 11" means that the substantially parallel portions 16 extend at angles of 0 ° to 30 ° and 150 ° to 180 ° with respect to the surface 12 of the base layer 11.

Whether the fibers 13 extend substantially perpendicularly to the surface 12 of the base layer 11 or substantially parallel thereto is determined using a power spectrum obtained by image analysis of a cross-sectional photograph of the fiber layer 14 by two-dimensional fourier transform. The detailed determination method is described in the "measurement method" described later.

The principle of image analysis by two-dimensional fourier transform is described in detail in, for example, the following references 1 to 3 and reference URL 1.

Reference 1: "the person who is doing business before Jiangqian", "the person who is doing business を using いた (person who uses image processing)" physical property analysis method, pulp technology Times 48(11), 1-5(2005)

Reference 2: enomae, T.T., Han, Y.H.and Isogai, A., "Fiber orientation distribution of paper surface calculated by image analysis," Proceedings of International paper mapping and environmental Conference, Tianjin, P.R. China (May 12-14), book2,355-368(2004)

Reference 3: enomae, T.A., Han, Y.H.and Isogai, A., "Nondestructive determination of fiber orientation distribution of fiber surface by image analysis," Nordic Pump Research Journal 21(2):253-

Reference URL 1: htp:// www.enomae.com/FiberOri/index. htm (1 month in 2018)

Since the fibers 13 are substantially parallel in the substantially parallel portion 16, the interval between the fibers 13 is appropriately narrowed, and liquid droplets are less likely to enter between the fibers 13, thereby exhibiting liquid repellency. Since the fibers 13 are substantially vertical in the substantially vertical portion 15, an air layer is formed between the fibers 13 favorably, and the liquid repellency is improved. Here, if the fibers 13 in the substantially vertical portion 15 are inclined beyond the substantially vertical state, the fibers 13 are inclined at the root, and it becomes difficult to support the fibers 13 on the side away from the base layer 11 in a self-supporting manner. As a result, an air layer is hardly formed, and liquid repellency may be lowered.

When comparing the substantially vertical portion 15 and the substantially parallel portion 16, the fibers 13 in the substantially vertical portion 15 are relatively sparse, and the fibers 13 in the substantially parallel portion 16 are relatively dense in many cases. When the fibers 13 in the substantially vertical portions 15 are relatively sparse, an air layer is formed in the fiber layer 14 well, and liquid repellency is improved. Since the fibers 13 in the substantially parallel portions 16 become relatively dense, intrusion of liquid into the fiber layer 14 can be prevented, and liquid repellency is improved.

From another viewpoint, an embodiment of the resin structure of the present invention will be described below. Fig. 3 is a schematic surface view of a film as the resin structure 10 of the present invention, as viewed from the fiber-side surface, and fig. 4 is a schematic view showing the structure of the base layer surface of the film as the resin structure 10 of the present invention. Fig. 3 is a view of resin structure 10 of fig. 1 viewed from a direction a, and fig. 4 is a view of resin structure 10 of fig. 1 viewed from a B-B cross section.

As shown in fig. 3, one surface of the resin structure 10 is almost completely covered with a fiber layer 14 composed of a plurality of fibers 13. When resin structure 10 is viewed from the surface on the fiber layer 14 side, the ratio of the area occupied by fibers 13 is 80% or more of the surface area of base layer 11.

As shown in fig. 4, the ratio of the area of the portion bonded to the fibers 13 on the surface 12 of the base layer 11 is 5 to 40% of the surface area of the surface of the base layer 11 on which the fiber layer 14 is formed.

That is, almost the entire surface of the resin structure 10 is densely covered with the fibers 13, and liquid droplets are less likely to enter between the fibers 13, thereby exhibiting liquid repellency. Since the surface 12 of the base layer 11 has a larger proportion of air than the area of the portion bonded to the fibers 13, an air layer can be formed between the fibers 13, and the liquid repellency is improved.

The ratio of the area occupied by the fibers 13 when the resin structure 10 is observed from the surface on the fiber layer 14 side can be obtained by obtaining an observation photograph of the surface of the resin structure 10 using a scanning electron microscope and using a binarized image thereof.

The ratio of the area of the portion of the surface 12 of the base layer 11 to which the fibers 13 are bonded can be determined by the following method (i) or (ii).

(i) The fiber layer 14 is cut in parallel to the base layer 11 immediately above the base layer 11 of the resin structure 10, and a photograph of the cut section is obtained using a scanning electron microscope, and a binarized image of the photograph is obtained using the section.

(ii) Each of the cross sections obtained by cutting the resin structure 10 in the cross sections in the two directions perpendicular and orthogonal to the surface of the resin structure 10 was observed by using a scanning electron microscope. The number of fibers 13 present in each cross section and the average cross-sectional width of the fibers 13 are determined from the observation photograph of each cross section, and the ratio of bonding of the fibers 13 per unit length of the base layer 11 in each cross section is determined from the product of these. Further, the product of the ratio of the fibers 13 bonded to each cross section is obtained, and this value is defined as the ratio of the area of the portion of the surface 12 of the base layer 11 to which the fibers 13 are bonded. This method can be more easily obtained than the method (i) above.

In the present invention, the value measured by the method (i) is used as the ratio of the area of the portion of the surface 12 of the base layer 11 to which the fibers 13 are bonded. However, when the fibers are very fine, such as fibers having a fiber diameter of 1 μm or less, and even if the fiber layer 14 is cut by the method (i) above, the fibers 13 are inclined by the edge of the cutting blade, and it becomes difficult to cut the fiber layer 14, the value measured by the method (ii) above is used as the ratio of the area of the portion of the surface 12 of the base layer 11 to which the fibers 13 are bonded.

In the surface of the resin structure 10, when the fiber diameter is 0.05 μm or more and 3 μm or less, an air layer is easily formed in the space between the fibers, and the contact area between the liquid droplets and the air is increased, whereby the liquid repellency is improved, which is preferable. More preferably, the fiber diameter is 0.1 μm or more and 0.5 μm or less. When the fiber diameter is 0.05 μm or more, the fiber is less likely to be broken or deformed, and the durability is improved. Further, since the fibers 13 are not easily broken when the resin forming the fibers 13 is stretched, a sufficient fiber layer 14 can be formed. In particular, when the fiber diameter is 0.1 μm or more, the fibers 13 are less likely to fall down on the surface of the base layer when the resin forming the fibers 13 is stretched, and a sufficient substantially vertical portion is easily formed. When the fiber diameter is 3 μm or less, an air layer can be sufficiently formed between the fibers, and a liquid repellent effect is exhibited. In particular, when the fiber diameter is 0.5 μm or less, the fibers 13 are easily intertwined with each other when the resin is drawn to form the fibers 13, and a sufficient substantially parallel portion is easily formed on the side away from the base layer. Here, the fiber diameter means an observation photograph of the surface obtained by using a scanning electron microscope, and the fiber diameter is determined by selecting arbitrary 30 fibers 13 and measuring the maximum width of each of the fibers, removing 5 fibers from the fibers having the maximum width, removing 5 fibers from the fibers having the small width, and taking the average of the maximum widths of the middle 20 fibers 13.

The number of fibers 13 is 10000 μm on the surface 12 of the base layer 11 ² In the root system, more than 2000 and 3 × 10 ⁶ The following is preferable because the liquid droplets present on the surface of the resin structure 10 are easily supported by the fibers 13, and the contact area between the liquid droplets and the air increases, thereby improving the liquid repellency. 10000 μm ² The number of the fibers 13 in (A) is 3X 10 ⁶ At the time of droplet deposition, since a sufficient air layer can be present between the fibers 13, the contact area with air is sufficient, and a liquid repellent effect is exhibited. 10000 μm of the surface 12 of the base layer 11 ² When the number of the fibers 13 in (2) is 2000 or more, the intervals between the fibers 13 are appropriately narrowed, and liquid droplets are hard to enter between the fibers 13, and liquid repellency is exhibited without causing contact between the surface of the base layer 11 and the liquid droplets. In particular, when the fiber diameter is 0.5 μm or less, 10000 μm of the surface 12 of the base layer 11 is formed ² When the number of fibers 13 in (2) is 10000 or more, droplets present on the surface of the resin structure 10 are easily supported by the fibers 13, which is more preferable. Here, regarding the number of fibers 13, a scanning electron microscope is used to obtain an observation photograph of a cross section obtained by cutting the resin structure 10 parallel to the base layer 11 from immediately above the base layer 11 of the resin structure 10, and the number of fibers 13 can be read from the photograph. Alternatively, a mold of the surface of the resin structure 10 may be obtained from liquid silicone rubber or the like, and an image may be read from the surface of the mold. When the resin structure 10 is peeled from the cured liquid silicone rubber, the surface of the liquid silicone rubber is a surface on which many holes corresponding to the bottom surfaces of the fibers 13 (surfaces bonded to the surface 12 of the base layer 11) are opened. A scanning electron micrograph of the surface was taken, and the number of fibers 13 was determined. In addition, as a simple method, it is also possible to form a cross section in two directions perpendicular and perpendicular to the surface of the resin structure 10Each cross section obtained by cutting the resin structure 10 was observed by a scanning electron microscope to determine the number of fibers 13 per 100 μm in each cross section, and the product of the numbers was determined for each 10000 μm ² The number of fibers 13.

The thickness of the fiber layer 14 is preferably 5 μm or more and 50 μm or less. Here, the thickness of the fiber layer 14 is a thickness of the fiber layer 14 obtained by measuring 10 positions where the distance from the surface 12 of the base layer 11 to the outermost surface is large, by taking an average value of the 10 positions as an observation photograph of a cross section obtained by cutting the structure in a cross section perpendicular to the surface of the resin structure 10, using a scanning electron microscope. When the fiber layer 14 is 5 μm or more, an air layer can be formed between the fiber 13 and the liquid droplets when the liquid droplets are attached, and thus a liquid repellent effect can be obtained. When the fiber layer is 50 μm or less, it takes no time to obtain the fiber 13. Further, the fibers 13 are less likely to fall down, deform, and the like, and have sufficient durability.

The resin structure 10 of the present invention can be suitably used in the form of a film, but is not limited to a film, and may be in any shape as long as it can be thermoformed into a surface, and a film is preferable from the viewpoint of productivity and cost.

Further, the material of the resin structure 10 may be any material as long as it can form the fibers 13, and a fluororesin, a silicone-based resin, a polyester-based resin such as polyethylene terephthalate, polyethylene 2, 6-naphthalate, polypropylene terephthalate, polybutylene terephthalate, a polyolefin-based resin such as polyethylene, polystyrene, polypropylene, polyisobutylene, polybutylene, polymethylpentene, a polyamide-based resin, a polyimide-based resin, a polyether-based resin, a polyesteramide-based resin, a polyether-based resin, an acrylic-based resin, a polyurethane-based resin, a polycarbonate-based resin, a polyvinyl chloride-based resin, or the like is preferably used. In particular, a fluorine-based resin or a silicone-based resin having a low surface energy, a polyolefin-based resin such as polyethylene, polystyrene, polypropylene, polyisobutylene, polybutene, and polymethylpentene, or the like is preferably used. The material of the resin structure 10 preferably contains these resins as a main component. The main component is a component that accounts for 50 mass% or more of the total resin constituting the resin structure when the total resin is 100 mass%. The main component is preferably 50% by mass or more, and more preferably 80% by mass or more.

Further, various additives can be added to the material of the resin structure 10 of the present invention during or after polymerization. Examples of additives that can be added and blended include organic fine particles, inorganic fine particles, dispersants, dyes, fluorescent brighteners, antioxidants, weather resistance agents, antistatic agents, mold release agents, tackifiers, plasticizers, pH adjusters, and salts. In particular, as the release agent, a small amount of a low surface tension carboxylic acid such as a long-chain carboxylic acid or a long-chain carboxylate and/or a derivative thereof, a long-chain alcohol and/or a derivative thereof, a low surface tension alcohol compound such as a modified silicone oil, and the like are preferably added at the time of polymerization.

In the resin structure 10, another layer may be laminated on the side of the base layer 11 opposite to the side on which the fiber layer 14 is laminated. In this case, the above-described materials may be used only in the base layer 11 and the fiber layer 14. By forming the other layers with a resin having higher strength and heat resistance than the resin forming the base layer 11, the planarity is improved during molding, and deformation and wrinkles of the resin structure 10 can be suppressed.

The resin structure 10 may be a continuous body or a single body. The thickness of the resin structure 10 is not particularly limited.

[ method for producing resin Structure ]

The method for producing the resin structure of the present invention includes the steps of: a step of disposing a resin composition on a surface of a mold having a plurality of fine holes formed in a surface thereof, the surface having the fine holes formed therein, a step of pressing the mold and the resin composition while heating to press a part of the resin composition into the holes (hereinafter, referred to as a "pressing step"), a step of cooling the resin composition in a state in which a part of the resin composition is present in the holes (hereinafter, referred to as a "cooling step"), and a step of forming a plurality of fibers in which the resin composition is drawn by drawing the resin composition present in the holes and peeling the resin composition from the mold to form a resin structure composed of a fiber layer composed of the fibers and a base layer not including the fibers (hereinafter, and a peeling step) of sequentially performing the steps to form a resin structure in which the fiber layer is composed of substantially vertical portions and substantially parallel portions, the substantially vertical portions are present on a side close to the base layer, the fibers in the substantially vertical portions extend substantially perpendicularly to a surface of the base layer, the substantially parallel portions are present on a side away from the base layer, and the fibers in the substantially parallel portions extend substantially parallel to the surface of the base layer.

In the case where a resin structure having a desired shape cannot be formed by only the above steps, the following step (hereinafter, referred to as "pressing step") may be performed after the peeling step: and applying a pressure to the resin structure from a direction substantially perpendicular to the fiber layer so that the fiber layer is composed of substantially perpendicular portions and substantially parallel portions, the substantially perpendicular portions being present on a side close to the base layer, the fibers in the substantially perpendicular portions extending substantially perpendicular to a surface of the base layer, the substantially parallel portions being present on a side away from the base layer, and the fibers in the substantially parallel portions extending substantially parallel to the surface of the base layer and being interlaced with each other.

The film as one embodiment of the resin structure 10 of the present invention can be produced, for example, by the steps of the apparatus shown in fig. 5, 6, and 7.

Fig. 5 and 7 are schematic cross-sectional views of

manufacturing apparatuses

50 and 70 for manufacturing a resin structure 10 (film) having a fiber layer 14 on a surface 12 of a base layer 11. Fig. 6 is a schematic cross-sectional view showing an operation of peeling the resin structure 10 (film) from the mold in the manufacturing apparatus 50.

In the example shown in fig. 5, in the unwinding unit 52, the film 10 ' of the material is drawn out from the unwinding roller 51 in advance, and then the heated die 53 having fine holes formed on the surface thereof is pressed against the intermittently fed film 10 ' in the pressing unit 54 and pressed, and then cooled while maintaining the contact state, so that a fine projection structure corresponding to the fine holes of the die 53 is formed on the surface of the film 10 '.

The molding section is composed of a pressing means 54 for forming a predetermined fine projection structure and a peeling means 55, and the peeling means 55 is a means for peeling the film 10 ″ which is stuck to the mold 53 by pressing and has a fine projection structure formed on the surface thereof, from the mold 53. The peeling unit 55 is composed of a pair of peeling rollers 55A and a peeling auxiliary roller 55B arranged in parallel to hold the peeled film 10 in an S-shape. One surface of the intermittently fed film 10' is thermoformed by the die 53 in the pressing unit 54, and a film 10 ″ having a fine protrusion structure formed on the surface thereof is obtained. After thermoforming, as shown in fig. 6, the peeling unit 55 is moved toward the upstream side, and the film 10 ″ stuck to the mold 53 is sequentially peeled from the mold 53, whereby the film 10 having the fiber layer 14 on the surface 12 of the base layer 11 can be obtained. Then, the film 10 is wound on the winding roll 56.

In fig. 5,

reference numerals

57 and 58 denote pressing plates, and

reference numerals

59 and 60 denote buffer units provided to smoothly perform intermittent conveyance of the film 10' in the die 53 portion.

In fig. 6, the diameter of the fiber 13 and the thickness of the fiber layer 14 formed by drawing the molded fine protrusion structure can be changed by adjusting the distance 55H between the peeling roller 55A and the die 53 and the temperature of the die 53 at the time of peeling. For example, a method of setting the temperature of the mold 53 at the melting point of the resin composition as the material of the film 10 or higher at the molding time and setting the temperature of the mold 53 at the glass transition temperature of the resin composition as the material of the film 10 or higher at the peeling time may be mentioned.

When the drawn fibers 13 themselves have no rigidity, the drawn fibers 13 fall in a nonuniform direction due to the tip ends of the fibers 13 being separated from the die 53, and the fibers 13 are entangled with each other. At this time, since the fibers 13 are interlaced from the portion where the fibers 13 are separated from the mold 53 last, that is, the tip portion of the fibers 13, in the portion of the film 10 separated from the surface 12 of the base layer 11, the fibers 13 interlaced with each other are dense, and the substantially parallel portion 16 extending substantially parallel to the base layer 11 is formed. On the other hand, since the fibers 13 that are first peeled off from the die 53 at the time of peeling hardly intertwine in the portion immediately above the base layer 11, the substantially perpendicular portions 15 in which the fibers 13 extend in a state substantially perpendicular to the surface 12 of the base layer 11 are formed on the side closer to the base layer 11 than the substantially parallel portions 16.

When the rigidity of the drawn fibers 13 is high and the entanglement of the fibers 13 is small, the density of the fiber layer 14, the inclination angle of the fibers 13, and the thickness of the fiber layer 14 can be adjusted by applying pressure with the nip roller 62 of fig. 5. For example, when the pressure is increased, the fiber layer 14 becomes thin, the fibers 13 on the tip side are inclined to be substantially parallel, and the density of the fibers 13 in the substantially parallel portion 16 is increased.

In the example shown in fig. 7, the film 10' is drawn from the unwinding roll 73, and is supplied onto a heated endless belt-shaped die 76 having a fine pore structure formed on the surface thereof through a heating roll 75.

On the outer surface of the mold 76, fine holes are formed in an independent and discrete arrangement, and are heated by a heating roller 75 immediately before contacting the film 10'. The continuously fed film 10 'is pressed against the surface of the mold 76 where the fine pore structure is formed by the nip roller 77, and a fine protrusion structure corresponding to the fine pore structure of the mold 76 is formed on the surface of the film 10'. In order to sufficiently insert the surface of the film 10 'into the fine holes of the mold 76, the temperature at which the film 10' is pressed against the surface of the mold 76 in which the fine hole structure is formed is preferably not lower than the glass transition temperature of the film 10 ', and more preferably not lower than the melting temperature of the film 10'.

Then, the film 10 ″ having the fine projection structure formed on the surface thereof is conveyed to the outer surface position of the cooling roll 78 in a state of being in close contact with the surface of the mold 76. The film 10 ″ is cooled by heat conduction through the mold 76 by the cooling roll 78, and then the molded fine protrusion structure is stretched by the peeling roll 79 and peeled from the mold 76, thereby obtaining the film 10 having the fiber layer 14 on the surface 12 of the base layer 11. The film 10 is wound onto a winding roll 82. Through such a process, the film 10 on which the fibers 13 are formed can be continuously thermoformed with high productivity.

The diameter of the fiber 13 and the thickness of the fiber layer 14 formed by drawing the molded fine protrusion structure can be changed by adjusting the distance 79H between the peeling roller 79 and the die 76 and the temperature of the cooling roller 78.

Further, by applying pressure by the nip roller 81, the density of the fiber layer 14, the inclination angle of the fibers 13, and the thickness of the fiber layer 14 can be adjusted. For example, when the pressure is increased, the fiber layer 14 becomes thin, the fibers 13 on the tip side are inclined to be substantially parallel, and the density of the fibers 13 in the substantially parallel portion 16 increases.

The area ratio of the fine pores formed on the surface of the

mold

53 or 76 is almost the ratio of the area of the portion bonded to the fibers 13 on the surface of the base layer 11 of the film 10, and therefore the area ratio of the fine pores formed on the surface of the

mold

53 or 76 is preferably 5% to 40%. The diameter of the fine pores formed on the surface of the

molds

53 and 76 is preferably 0.05 to 3 μm, and more preferably 0.1 to 0.5. mu.m. When the diameter of the minute holes formed in the surfaces of the

molds

53 and 76 is 0.05 μm or more, a part of the thin film 10' is easily press-fitted in the press-fitting step. In addition, when the thickness is 0.1 μm or more, the fibers 13 stretched in the peeling step are less likely to fall down on the surface of the base layer, and a substantially vertical portion is likely to be formed. When the thickness is 0.5 μm or less, the tip end portions of the fibers 13 stretched in the peeling step are likely to fall down, and the fibers 13 are likely to be entangled with each other in the substantially parallel portions 16. When the thickness is 3 μm or less, the fiber 13 stretched in the separation step is easily deformed in the pressing step.

The depth of the minute holes formed on the surface of the

molds

53 and 76 is preferably 2.5 times or more the diameter of the holes. When the depth of the hole is 2.5 times or more the diameter of the hole, the area of the resin pressed into contact with the side surface of the hole of the

mold

53 or 76 in the press-fitting step is preferably 10 times or more the surface area of the hole portion, and the resin is easily stretched in the peeling step. The depth of the pores is more preferably 10 times or more as large as the pore diameter. The depth of the hole is not particularly limited to the upper limit of the hole diameter, but is preferably about 100 times as large as the hole diameter in view of the ease of forming the hole.

Examples of the method of manufacturing the dies 53 and 76 having a plurality of fine holes formed on the surface thereof include a method of directly cutting, laser processing, and electron beam processing the metal surface, a method of directly cutting, laser processing, and electron beam processing the plating film formed on the metal surface, and a method of manufacturing a fine hole shape by electroforming after forming a convex shape opposite to the fine hole by performing laser processing, electron beam processing, and the like on the metal surface and the plating film formed on the metal surface. Further, there is a method in which a resist is applied to a substrate, the resist is formed in a predetermined pattern by photolithography, the substrate is etched to form a shape, the resist is removed, and a fine pore structure is obtained by electroforming in accordance with the reverse pattern.

Further, by etching the surface of the mold, the

molds

53 and 76 having a fine pore structure on the surface can be manufactured. The material of the

molds

53 and 76 may be any material having strength and workability with required accuracy, such as a silicon wafer, various metal materials, glass, ceramics, plastics, or carbon material, and specifically may be Si, SiC, SiN, polycrystalline Si, glass, Ni, Cr, Cu, Al, Fe, Ti, C, or 1 or more kinds of materials including these. Alternatively, the surface of a mold having an amorphous structure containing the above-described material as a main component on the surface thereof may be etched with a strongly acidic liquid.

The shape of the fiber 13 can be controlled by adjusting the conditions of each of the press-fitting step, the cooling step, and the peeling step, in addition to the shape of the fine pores on the surface of the dies 53 and 76. For example, if the pore diameter of the fine pore shape on the surface of the dies 53 and 76 is reduced, the fiber diameter is reduced, and the fiber diameter and the thickness of the fiber layer 14 can be changed by changing the cooling temperature in the cooling step and the drawing speed in the peeling step.

In the pressing step, the pressure applied may be appropriately changed according to the form of the fibers 13, and the inclination angle, the degree of density, and the thickness of the fiber layer 14 can be changed by the pressure.

In the present invention, when it is desired to further increase the contact angle with water and further improve the liquid repellency, the surface of the fiber 13 obtained by the above operation is preferably coated with a functional group having a low surface energy, particularly a fluorine group.

The coating method is not particularly limited as long as the structure of the fiber 13 is not filled with the coating material, and examples thereof include a Langmuir Blodgett method (LB method), a physical deposition method (PVD method), a chemical deposition method (CVD method), a self-organization method, a sputtering method, a method of applying a coating liquid in which a single molecule is diluted with a solvent, and the like.

The fibers 13 can be formed by the above-described method after the liquid-repellent treatment of an arbitrary thickness is performed on the film 1O' on which the fibers 13 are formed using the above-described material.

The resin structure of the present invention can be suitably used for, for example, a biological device such as a cell culture sheet or a biochip, an optical device such as an optical film or an anisotropic film, a building material such as a liquid repellent sheet or an antifouling sheet, by utilizing the surface properties thereof.

The resin structure of the present invention has not only liquid repellency but also can be used for other applications such as a heat insulating sheet because an air layer is included in the vicinity of the base layer of the resin structure.

Examples

[ measurement method ]

[ determination of substantially vertical portion and substantially parallel portion ]

The presence or absence of the substantially perpendicular portion 15 in which the fibers 13 extend in a state substantially perpendicular to the surface 12 of the base layer 11 and the substantially parallel portion 16 in a state substantially parallel to each other in the film 10 molded in the example and the like is determined by the following procedure.

(1) A sample of 10 mm. times.10 mm was cut from an arbitrary position of the resin structure 10. 1 section was arbitrarily selected from the 4 sections of the sample. The right end portion of the selected cut section, which is observed when the fiber layer 14 is the upper side and the base layer 11 is the lower side, is an observation target.

(2) A cross-sectional observation photograph of the observation target of item (1) was taken using a scanning electron microscope. The observation magnification is 5000 times, the observation object range is 24.3um × 18.2um, the pixel number is 1280 pixel × 960 pixel, and the size of 1 pixel is 19.0nm × 19.0 nm. The obtained photograph was cut to become a photograph of only the fiber layer 14, and was divided into 3 parts in a direction parallel to the surface 12 of the base layer 11. In the divided portions, the sectional photographs of the portion farthest from the base layer 11 and the portion closest to the base layer 11 are subjected to image analysis by two-dimensional fourier transform, respectively, to obtain power spectrum images.

(3) The average brightness in all orientations is calculated from the obtained power spectrum image and plotted, and then fitted to an ellipse using the least square method.

(4) The average value of the amplitudes is plotted for each angle of 0 to 180 degrees formed with the surface 12 of the base layer 11 from the power spectrum image obtained by ellipse fitting with the direction parallel to the surface 12 of the base layer 11 being 0 degree, and the ellipse fitting inclination angle distribution of the fibers 13 is calculated.

(5) When the average value of the average amplitudes of the fibers 13 having the elliptical fit inclination angle distribution of 0 degrees to 30 degrees and 150 degrees to 180 degrees is larger than the average value of the average amplitudes of more than 30 degrees and less than 150 degrees, it is determined that the fibers 13 are in a substantially parallel state in the cross-sectional photograph. When the average value of the average amplitudes of the elliptical fit inclination angle distribution of the fibers 13 is greater than the average value of the average amplitudes of 0 to less than 60 degrees and greater than 120 to 180 degrees, the fibers 13 in the cross-sectional photograph are determined to be in a substantially vertical state.

(6) The same operations as in items (2) to (5) are performed with respect to the cut surface facing the cut surface selected in item (1) and also with respect to the right end portion observed when the fiber layer 14 is the upper side and the base layer 11 is the lower side as the observation target. Further, the same operations as in items (2) to (5) were carried out by cutting the sample parallel to the cut surface selected in item (1) through the center of the sample of 10mm × 10mm, and observing the left and right center portions of the cut surface.

(7) If any of the 3 observation targets is in a state where the fibers 13 are substantially parallel to 1 part by 3 farthest from the base layer 11, it is determined that the fiber layer 14 is in a substantially parallel part by 1 part by 3 farthest from the base layer 11. If any of the 3 observation targets is in a state where the fibers 13 are substantially perpendicular to the portion closest to 1/3 of the base layer 11, it is determined that the portion closest to 1/3 of the base layer 11 of the fiber layer 14 is a substantially perpendicular portion.

A cross-sectional photograph used for image analysis by two-dimensional fourier transform is shown in fig. 8 (a), a power spectrum obtained by the image analysis is shown in fig. 8 (b), and an angle distribution diagram of the fiber 13 is shown in fig. 8 (c). Fig. 8 shows an example in which the fibers 13 extend substantially parallel to the surface 12 of the base layer 11.

In the present embodiment, for Fourier transformation of the basal plane dislocation image, Fiber organization Analysis Ver.8.03 developed by the authors of references 1 to 3 was used. The fourier transform software extracts luminance information of each point from the image data, performs fourier transform processing, and performs processing for obtaining a power spectrum and an average amplitude Aave (θ). The detailed procedures are described in the above references 1 to 3 and reference URL 1. In order to perform fourier transform processing on an image by this software, the image is bit mapped in advance to extract numerical information of luminance. Further, in order to perform the fast fourier transform, adjustment is performed in advance so that the number of pixels on one side of the image is an integral multiple of 4. When the fourier transform processing is performed on an image having an image pixel number of 3 or more, 5 original images are pasted in a direction in which the aspect ratio of the image to be subjected to the fourier transform processing becomes smaller, and the fourier transform processing is performed on 1 image.

Since the fourier transform process is a uniquely determined process, other software may be used as long as the same process can be performed. However, the present software developed for the orientation evaluation is characterized in that Aave (θ) can be obtained. When other software cannot automatically find ave. (θ), it is necessary to perform the same calculation using a power spectrum obtained by mapping the luminance to the (x, y) coordinate.

[ ratio of area occupied by fiber observed from surface on fiber layer side ]

The film 10 molded in example or the like was cut into a size of 10mm × 10mm, and the surface was observed by a scanning electron microscope (Chinesian VE-7800, Inc.) at a magnification of 10000 times by using a secondary electron image. The image size at this time was 12.1um × 9.1 um. The number of pixels is 1280 pixels × 960 pixels, and the size of 1 pixel is 9.4nm × 9.5 nm. The observation photograph was binarized into black and white, and the area of a bright portion (hereinafter referred to as "white portion") of the image as a whole was a ratio of the area of the fibers 13 observed from the surface on the fiber layer 14 side. The threshold for binarization was set to the following light value: a light amount value indicating the middle of two peaks of light amounts of a white portion and a dark portion (hereinafter, referred to as a "black portion"), and a light amount value indicating the minimum change in the ratio of the white portion to the black portion in binarization before and after the light amount value.

[ area of portion of the surface of the base layer to which fibers are bonded ]

Method (i) A film 10 molded in example or the like was cut into a size of 10mm × 10mm, a fiber layer 14 was cut parallel to the base layer 11 of the film 10 at a position within 1 μm from the base layer 11 of the film 10, and cut fibers 13 were removed from the cut cross section by wind. The surface 12 was observed by a secondary electron image at a magnification of 10000 times using a scanning electron microscope ((strain) kirnshi VE-7800). The image size at this time was 12.1. mu. m.times.9.1. mu.m. The number of pixels is 1280 pixels × 960 pixels, and the size of 1 pixel is 9.4nm × 9.5 nm. The observed photograph was binarized into black and white, and the area of a bright portion (hereinafter referred to as "white portion") of the image as a whole was defined as the area of the portion of the surface 12 of the base layer 11 to which the fibers 13 were bonded. The threshold for binarization was set to the following light value: a light amount value indicating the middle of two peaks of light amounts of a white portion and a dark portion (hereinafter, referred to as a "black portion"), and a light amount value indicating the minimum change in the ratio of the white portion to the black portion in binarization before and after the light amount value.

However, when the fiber layer 14 is cut by the above-described method (i), the fiber 13 is very thin, and the fiber 13 is inclined by the cutting edge of the cutting blade, and it is difficult to cut the fiber layer 14 from the base layer 11, the result is obtained by the following method (ii).

[ method (ii) ] the film 10 was cut in two directions perpendicular and perpendicular to the surface of the film 10, and each cross section was observed at a magnification of 5000 times using a scanning electron microscope ((product of Ltd.) -Keynshi VE-7800). The image size at this time was 24.3. mu. m.times.18.2. mu.m. The number of pixels is 1280 pixels × 960 pixels, and the size of 1 pixel is 19.0nm × 19.0 nm. The number of fibers 13 present in the cross section and the average cross-sectional width of the fibers 13 are obtained, and the ratio of the fibers 13 bonded per unit length of the base layer 11 in each cross section is obtained from the product of the numbers and the average cross-sectional widths. Further, the product of the ratio of the fibers 13 bonded to each cross section is obtained, and this value is defined as the ratio of the area of the portion of the surface 12 of the base layer 11 to which the fibers 13 are bonded.

[ measurement of fiber diameter ]

The film 10 molded in example or the like was cut into a size of 10mm × 10mm, and the surface was observed by a scanning electron microscope (Chinesian VE-7800, Inc.) at a magnification of 10000 times by using a secondary electron image. The image size at this time was 12.1. mu. m.times.9.1. mu.m. The number of pixels is 1280 pixels × 960 pixels, and the size of 1 pixel is 9.4nm × 9.5 nm. An arbitrary 30 fibers 13 were selected from the observation photograph, 5 fibers were removed from the wide fibers, 5 fibers were removed from the narrow fibers, and the average of the widths of the middle 20 fibers 13 was taken as the fiber diameter.

[ measurement of fiber count ]

The film 10 molded in example or the like was cut into a size of 10mm × 10mm, and the surface was observed by a scanning electron microscope (Chinesian VE-7800, Inc.) at a magnification of 10000 times by using a secondary electron image. The image size at this time was 12.1. mu. m.times.9.1. mu.m. The number of pixels is 1280 pixels × 960 pixels, and the size of 1 pixel is 9.4nm × 9.5 nm. The number of fibers 13 is read from the image. In the measurement of the number of fibers 13, the fibers 13 are marked with a sniping Tool and measured. The number of fibers obtained in the method is converted into 10000 μm ² The number of fibers in (1).

In the case where the fibers 13 are interlaced and it is difficult to read the number of fibers 13 from the surface photograph, a mold of the surface of the film 10 may be obtained from liquid silicone rubber or the like, and an image may be read from the surface of the mold. When the film 10 is peeled off from the cured liquid silicone rubber, the surface of the liquid silicone rubber becomes a surface on which many holes corresponding to the bottom surfaces of the fibers 13 are opened. A scanning electron micrograph of the surface was taken, and the number of fibers 13 was determined.

[ measurement of thickness of fiber layer ]

The film 10 molded in example and the like was cut in a direction perpendicular to the surface of the film 10, and the cross section thereof was observed at a magnification of 5000 times using a scanning electron microscope (e.g., kirschner VE-7800). The image size at this time was 24.3. mu. m.times.18.2. mu.m. The number of pixels is 1280 pixels × 960 pixels, and the size of 1 pixel is 19.0nm × 19.0 nm. In the observation photograph of the cross section, 10 points were measured for a portion having a large distance from the surface of the base layer 11 to the outermost surface, and the average value of the distances of the 10 points was taken as the thickness of the fiber layer 14.

When the film 10 is cut in a cross section perpendicular to the surface or when the film 10 is cut in parallel to the base layer 11 from immediately above the base layer 11 of the film 10, the film 10 and the fiber layer 14 can be fixed together with a cured resin, ice, or the like without damaging the structure of the fiber layer 14, and then cut, ground, or the like, in addition to cutting the film 10 alone. In the case where the film 10 has high liquid repellency and is difficult to hold resin, ice, or the like, hydrophilization may be performed by lyophilic treatment (corona discharge treatment, plasma treatment) in a range that does not damage the surface structure of the film 10, and then the film may be fixed with cured resin or ice and cut.

[ measurement of liquid repellency ]

A film 10 formed in example and the like was cut out to a size of 10 mm. times.30 mm, and the contact angle of a water droplet was measured by using a contact angle meter (CA-D model, manufactured by Kyowa Kagaku K.K.). Using pure water as a measurement solution, 1.41. mu.L of pure water was dropped onto the film surface. For the measurement, 10 spots in the film were measured, and the average value of 10 spots was taken as the contact angle.

[ non-adhesion test ]

The film 10 molded in example and the like was cut into pieces of 10mm × 30mm, and fixed to a fixing jig with the measurement surface facing upward. Then, 0.3ml of yogurt (Sendzein Behchends original flavor plus sugar type) was dropped while the fixing jig was tilted at 45 °, and the time from the dropping to the movement of 20mm was measured. In addition, the adhesion residue of yogurt was visually observed. The residue was evaluated as "good" except for the above-mentioned residue.

[ durability test ]

A film 10 molded in example or the like was cut into a size of 10mm × 30mm as a sample, the sample was fixed on a tray of 100mm × 100mm, 200ml of pure water was poured into the tray, and the tray was immersed for 24 hours. After 24 hours, the sample was taken out and dried at room temperature for 24 hours, and after drying, the contact angle of the water droplet was measured using a contact angle meter (CA-D type, manufactured by synechia interfacial science). Using pure water as a measurement liquid, 1.41. mu.L of pure water was dropped onto the sample surface. For the measurement, 10 points in the sample were measured, and the average value of the 10 points was taken as the contact angle after the durability test, and the change in the contact angle before and after the durability test was calculated. In addition, when the liquid droplets did not adhere to the sample surface and the contact angle could not be measured, the presence or absence of the change in the contact angle before and after the durability test was evaluated.

(example 1)

(1) Film(s)

A film comprising a polypropylene-based polymer (melting point: 144 ℃ C., glass transition temperature: 20 ℃ C.) and having a thickness of 100 μm was used.

(2) Die set

The surface of the stainless steel sheet is coated with a material mainly composed of Ni having a thickness of about 100 μm. Then, a fine pore structure having a diameter of about 0.3 to 0.6 μm and a depth of about 7 to 10 μm is formed on the entire surface of the mold by laser processing to produce a mold. The area in which the fine holes are formed is 20% with respect to the surface in which the fine holes are formed.

(3) Molding apparatus and conditions

As the apparatus, a molding apparatus 50 shown in fig. 5 was used. The pressurizing unit 54 is a device that pressurizes by a hydraulic pump, and has 2

pressurizing plates

57 and 58 vertically mounted inside thereof and connected to a heating device and a cooling device, respectively. The die 53 is provided on the upper surface of the lower pressing plate 57. In addition, a peeling unit 55 for peeling off the film 10 ″ attached to the mold 53 is provided in the pressing unit 54.

The mold temperature during molding was 160 ℃ and the pressure was set to 10MPa over the entire surface as a pressurizing force. The pressing time was 60 seconds. The mold temperature during peeling was 50 ℃. The separation distance between the peeling roller and the film was 0.3 mm. The peeled film was pressurized at 0.6MPa by a nip roll 62, and then conveyed to a winding unit 61 on the downstream side to be wound.

(4) Result of molding

Fig. 9 is a surface photograph by a scanning electron microscope ((co) yanshi VE-7800) of the fiber-forming surface of the film 10 molded in example 1, and fig. 10 is a cross-sectional photograph by a scanning electron microscope ((co) yanshi VE-7800) of the film 10 molded in example 1. The molded film 10 is composed of a base layer 11 and a fiber layer 14 in which a plurality of fibers 13 are formed. The fiber layer 14 is constituted by a substantially vertical portion 15 and a substantially parallel portion 16, the substantially vertical portion 15 being present on the side close to the base layer 11 and including the fibers 13 substantially perpendicular to the surface 12 of the base layer 11, the substantially parallel portion 16 being present on the side away from the base layer 11 and including the fibers 13 substantially parallel to the surface 12 of the base layer 11, and the fibers extending in a state of being interlaced with each other. The substantially vertical portion 15 has relatively thin fibers 13, and the substantially parallel portion 16 has relatively dense fibers 13. The fiber diameter was 0.3 μm and the thickness of the fiber layer 14 was 10.0. mu.m. 10000 μm ² The number of fibers 13 formed in (2) is 16700. The area of the portion of the surface 12 of the base layer 11 to which the fibers 13 are bonded is measured by method (ii). The measured values of the resulting fibers 13 are shown in table 1.

(5) Liquid repellency and liquid droplet migration Effect

1.41. mu.L of water was dropped onto the surface of the fiber layer 14 of the formed film 10, and the contact angle of the water drop was measured using a contact angle meter (CA-D, manufactured by Kyowa Kagaku Co., Ltd.). When a water droplet is dropped, the water droplet rolls on the surface of the film 10 and cannot stay at one place, and therefore the contact angle cannot be measured. 0.3ml of yogurt was dropped onto the surface of the film 10 inclined at 45 °, and the time taken for the droplets to move 20mm after dropping was 0.2s, so that no adhesion residue remained.

(6) Durability test

The molded film 10 was immersed in pure water for 24 hours, dried, and then 1.41. mu.L of water was dropped onto the surface of the fiber layer 14, and the contact angle of the water drop was measured using a contact angle meter (CA-D, manufactured by Kyowa Kagaku Co., Ltd.). When a water droplet is dropped, the water droplet rolls on the surface of the film 10 even after the durability test and cannot stay at one place, and therefore the contact angle cannot be measured.

(example 2)

(1) Film(s)

The same film as in example 1 was used.

(2) Die set

The same mold as in example 1 was used.

(3) Molding apparatus and conditions

A film was formed under the same conditions as in example 1, except that the same molding apparatus 50 as in example 1 was used and the mold temperature during molding was 150 ℃.

(4) Result of molding

FIG. 11 is a surface photograph taken by a scanning electron microscope (Kyowa VE-7800, Ltd.) of the fiber-forming surface of the film 10 molded in example 2, and FIG. 12 is a cross-sectional photograph taken by a scanning electron microscope (Kyowa VE-7800, Ltd.) of the film 10 molded in example 2. The formed film 10 is composed of a base layer 11 and a fiber layer 14 in which a plurality of fibers 13 are formed. The fiber layer 14 is constituted by a substantially vertical portion 15 and a substantially parallel portion 16, the substantially vertical portion 15 being present on the side close to the base layer 11 and including the fibers 13 substantially perpendicular to the surface 12 of the base layer 11, the substantially parallel portion 16 being present on the side away from the base layer 11 and including the fibers 13 substantially parallel to the surface 12 of the base layer 11, and the fibers extending in a state of being interlaced with each other. The fibers 13 are relatively sparse in the generally vertical portions 15 and the fibers 13 are relatively dense in the generally parallel portions 16. The fiber diameter was 0.6 μm and the thickness of the fiber layer was 5.0. mu.m. 10000 μm ² The number of the fibers 13 formed in (2) is 10300. The area of the portion of the surface 12 of the base layer 11 to which the fibers 13 are bonded is measured by method (i). The measured values of the resulting fibers 13 are shown in table 1.

(5) Liquid repellency and liquid droplet migration Effect

The contact angle of a water droplet was measured under the same conditions as in example 1. When a water droplet is dropped, the water droplet rolls on the surface of the film 10 and cannot stay at one place, and therefore the contact angle cannot be measured. 0.3ml of yogurt was dropped onto the surface of the film 10 inclined at 45 °, and the time taken for the droplets to move 20mm after dropping was 0.4s, so that no adhesion residue remained.

(6) Durability test

The contact angle of a water droplet was measured under the same conditions as in example 1. When a water droplet is dropped, the water droplet rolls on the surface of the film 10 even after the durability test and cannot stay at one place, and therefore the contact angle cannot be measured.

(example 3)

(1) Film(s)

The same film as in example 1 was used.

(2) Die set

The same mold as in example 1 was used.

(3) Molding apparatus and conditions

A film was formed under the same conditions as in example 1, except that the same molding apparatus 50 as in example 1 was used and the mold temperature at the time of peeling was 80 ℃.

(4) Result of molding

FIG. 13 is a surface photograph taken by a scanning electron microscope (Kyowa VE-7800, Ltd.) of the fiber-forming surface of the film 10 molded in example 3, and FIG. 14 is a cross-sectional photograph taken by a scanning electron microscope (Kyowa VE-7800, Ltd.) of the film 10 molded in example 3. The molded film 10 is composed of a base layer 11 and a fiber layer 14 in which a plurality of fibers 13 are formed. The fiber layer 14 is constituted by a substantially vertical portion 15 and a substantially parallel portion 16, the substantially vertical portion 15 being present on the side close to the base layer 11 and containing the fibers 13 substantially perpendicular to the base layer surface, the substantially parallel portion 16 being present on the side away from the base layer 11 and containing the fibers 13 substantially parallel to the base layer surface, and the fibers extending in a state of being interlaced with each other. The fibers 13 are relatively sparse in the generally vertical portions 15 and the fibers 13 are relatively dense in the generally parallel portions 16. The fiber diameter was 0.45 μm and the thickness of the fiber layer 14 was 6.0μm。10000μm ² The number of fibers 13 formed in (2) is 12700. The area of the portion of the surface 12 of the base layer 11 to which the fibers 13 are bonded is measured by method (ii). The measured values of the resulting fiber 13 are shown in table 1.

(5) Liquid repellency and liquid droplet migration Effect

The contact angle of a water droplet was measured under the same conditions as in example 1. When a water droplet is dropped, the water droplet rolls on the surface of the film 10 and cannot stay at one place, and therefore the contact angle cannot be measured. 0.3ml of yogurt was dropped onto the surface of the film 10 inclined at 45 °, and the time taken for the dropped yogurt to move 20mm was 0.3s, and no adhesion residue remained.

(6) Durability test

Comparative example 1

(1) Film(s)

A film comprising a polymer having cycloolefin as a main component (glass transition temperature 138 ℃ C.) and having a thickness of 100 μm was used.

(2) Die set

The surface of the stainless steel sheet is coated with a material mainly composed of Ni having a thickness of about 100 μm. Then, a fine pore structure having a diameter of 0.5 to 1.0 μm and a depth of about 3 to 5 μm is formed on the entire surface of the mold by laser processing to manufacture a mold. The area in which the fine holes were formed was 21% with respect to the surface.

(3) Molding apparatus and conditions

pressurizing plates

57 and 58 vertically mounted inside thereof and connected to a heating device and a cooling device, respectively. The mold 53 is provided on the upper surface of the lower pressing plate 57. In addition, a peeling unit 55 for peeling off the film 10 ″ attached to the mold 53 is provided in the pressing unit 54. The mold temperature during molding was 165 ℃ and a pressure of 5MPa was applied to the entire surface as a pressurizing force. The pressing time was 30 seconds. The mold temperature during the peeling was 80 ℃. The separation distance between the peeling roller 55A and the die 53 was 0.3 mm. The peeled film 10 is fed to the winding unit 61 on the downstream side and wound.

(4) Result of molding

FIG. 15 is a surface photograph of a scanning electron microscope ((Zhaynshi VE-7800, Ltd.)) of a molding surface of the film molded in comparative example 1, and FIG. 16 is a cross-sectional photograph of the scanning electron microscope ((Zhaynshi VE-7800, Ltd.)) of the film molded in comparative example 1. The formed film is composed of a base layer and a plurality of fibers formed on the entire surface of the base layer. The fibers had an average diameter of 0.35 μm and an average height of 1.2 μm, and were not drawn. 10000 μm ² The number of fibers formed in (1) is 14300. In addition, the range of the inclination angle of the fibers in the cross section obtained by cutting the film in the direction perpendicular to the surface of the base layer is within the range of 20 ° to 45 ° with respect to the direction perpendicular to the surface of the base layer, wherein 70% or more of the protrusions in the cross section are included. The fiber is drawn in a constant direction without a dense portion, and the fiber is not composed of a substantially parallel portion and a substantially perpendicular portion. The area of the portion of the surface of the base layer to which the fibers are bonded is measured by the method (ii). The measured values of the obtained fibers are shown in table 1.

(5) Liquid repellency and liquid droplet migration Effect

The contact angle of a water droplet was measured under the same conditions as in example 1. When a water droplet is dropped, the water droplet rolls on the surface of the film 10 and cannot stay at one place, and therefore the contact angle cannot be measured. When 0.3ml of yogurt was dropped onto the surface of the film 10 inclined at 45 °, the droplets stopped and did not move, and adhered to the surface.

(6) Durability test

The contact angle of a water droplet was measured under the same conditions as in example 1. When a water droplet was dropped, the contact angle after the durability test was 125 °, and the contact angle was decreased compared with that before the durability test.

[ Table 1]

Industrial applicability

The resin structure of the present invention is suitably used for products and parts requiring liquid repellency on the surface, such as microchannels, cell culture sheets, packaging materials, antifouling or waterproof sheets, recording materials, screens, diaphragms, ion exchange membranes, battery diaphragm materials, displays, and optical materials.

Description of the reference numerals

10: resin structure

11: base layer

12: surface of the substrate

13: fiber

14: fibrous layer

15: substantially vertical portion

16: substantially parallel portion

50: manufacturing apparatus

51: unwinding roller

52: unwinding unit

53: die set

54: pressurizing unit

55: stripping unit

55A: stripping roller

55B: stripping auxiliary roller

55H: the distance between the peeling roller 55A and the die 53

56: winding roller

57. 58: pressurizing plate

59. 60: buffer unit

61: winding unit

62: clamping roller

70: manufacturing apparatus

71: fiber forming surface

72: film(s)

73: unwinding roller

74: laminating device

75: heating roller

76: die set

77: clamping roller

78: cooling roller

79: stripping roller

79H, and (3): the stripping roller 79 is spaced from the die 76

80: transfer roll

81: clamping roller

82: winding roller

Claims

1. A resin structure comprising a base layer and a fiber layer composed of a plurality of fibers,

the fiber layer is constituted of a substantially vertical portion which exists on a side close to the base layer and in which the fibers extend in a state substantially perpendicular to a surface of the base layer, and a substantially parallel portion which exists on a side away from the base layer and in which the fibers extend in a state substantially parallel to the surface of the base layer,

the substantially perpendicular portions extend at an angle of 60 DEG to 120 DEG with respect to the surface of the base layer, the substantially parallel portions extend at an angle of 0 DEG to 30 DEG and 150 DEG to 180 DEG with respect to the surface of the base layer,

2. The resin structure according to claim 1, wherein the fibers constituting the fiber layer are bonded to and extend from the surface of the base layer, the area of the portion of the surface of the base layer to which the fibers are bonded is 5 to 40% of the surface area of the surface of the base layer on which the fiber layer is formed,

when the resin structure is viewed from the surface on the fiber side, the ratio of the area occupied by the fibers is 80% or more of the surface area of the base layer.

3. A method for producing a resin structure, the method comprising:

a step of disposing a resin composition on a surface of a mold having a plurality of fine holes formed on the surface thereof, the surface having the fine holes formed therein,

a step of pressing the mold and the resin composition while heating the mold and the resin composition to press a part of the resin composition into the hole,

a step of forming a resin structure comprising a fiber layer comprising the fibers and a base layer not comprising the fibers by drawing the resin composition present in the holes and simultaneously peeling the resin composition from the mold to form a plurality of fibers in which the resin composition is drawn,

forming a resin structure in which the fiber layer is composed of substantially vertical portions and substantially parallel portions, the substantially vertical portions being present on a side close to the base layer, the fibers in the substantially vertical portions extending substantially perpendicularly to the surface of the base layer, the substantially parallel portions being present on a side away from the base layer, and the fibers in the substantially parallel portions extending substantially parallel to the surface of the base layer,

the substantially perpendicular portions extend at an angle of 60 DEG to 120 DEG with respect to the surface of the base layer, and the substantially parallel portions extend at an angle of 0 DEG to 30 DEG and 150 DEG to 180 DEG with respect to the surface of the base layer.

4. A method for producing a resin structure, the method comprising:

a step of pressing the mold and the resin composition while heating to press a part of the resin composition into the hole,

a step of forming a resin structure comprising a fiber layer composed of the fibers and a base layer not containing the fibers by forming a plurality of fibers obtained by drawing the resin composition while drawing the resin composition present in the holes and peeling the resin composition from the mold, and a method for manufacturing a resin structure comprising a base layer not containing the fibers

A step of applying pressure to the resin structure from a direction substantially perpendicular to the fiber layer so that the fiber layer is composed of a substantially perpendicular portion and a substantially parallel portion, the substantially perpendicular portion being present on a side close to the base layer, and the fibers in the substantially perpendicular portion extending substantially perpendicular to a surface of the base layer, the substantially parallel portion being present on a side far from the base layer, and the fibers in the substantially parallel portion extending substantially parallel to the surface of the base layer,

in the manufacturing method, the above steps are performed in sequence,

5. The method for producing a resin structure according to claim 3 or 4, wherein the depth of the fine pores of the mold is 2.5 times or more the diameter of the pores, and the temperature of the mold when the resin composition is peeled from the mold is set to be equal to or higher than the glass transition temperature of the resin composition.