JP7782148B2 - Manufacturing method of laminate - Google Patents

Description

The present invention relates to a method for manufacturing a laminate having an uneven surface.

2. Description of the Related Art Conventionally, techniques have been developed for forming minute irregularities on the surfaces of various materials.
For example, in packaging materials, it is known to form irregularities on the lid material or the inner surface of the container to prevent the contents from adhering to the material. Also, there is known a technique for forming minute irregularities on optical materials to increase the haze and suppress transmission or surface reflection.
For each of these applications, there is an optimum surface unevenness structure, and the unevenness structure is formed by controlling it.

Patent Document 1 discloses a water-repellent laminate comprising, in this order, a substrate, an organic solvent-resistant sealant film layer, and an anti-adhesion layer, wherein the anti-adhesion layer contains a thermoplastic resin, water-repellent fine particles, and bead particles having an average particle size larger than that of the water-repellent fine particles.
It has been shown that such a laminate has an anti-adhesion layer that contains two types of particles of different sizes, which forms a unique uneven structure on the surface, significantly improving the anti-adhesion and water repellency of viscous contents.

Japanese Patent Application Laid-Open No. 2017-226199

However, as disclosed in Patent Document 1, when unevenness is formed using particles, it is not possible to prevent particles present near the surface from falling off. For example, when used as a packaging material, it is easy for foreign matter to be mixed into the contents, making it difficult to apply the material to anything other than a lid material.
Furthermore, Patent Document 1 does not specifically disclose a method for controlling the uneven structure, and further improvements are required to control the uneven structure.
Furthermore, in the unevenness forming technology of Patent Document 1, a laminate is manufactured by a batch process, but for mass production, it is required to manufacture large areas continuously.

The present invention aims to provide a manufacturing method for continuously producing laminates with surface irregularities that can be controlled and that do not involve particle shedding.

The gist of the present invention is as shown in the following [1] to [20].
[1] A resin layer precursor forming step (A) of applying a curable resin composition to at least one surface of a substrate to obtain a substrate with a resin layer precursor;
a surface treatment step (B) of performing a surface treatment by a dry process on the semi-cured or uncured substrate with the resin layer precursor to obtain a laminate having irregularities on the outermost surface;
and (C) a winding step of winding the laminate into a roll.
[2] After the resin layer precursor forming step (A),
a winding step (X) of winding the substrate with the resin layer precursor into a roll;
an unwinding step (Y) of unwinding the substrate with the resin layer precursor from the roll;
The method for producing a laminate according to the above [1], further comprising the step of performing a surface treatment (B).
[3] The method for producing a laminate according to the above [2], wherein the surface treatment step (B) and the winding step (C) are carried out while transporting the substrate with the resin layer precursor.
[4] The method for producing a laminate according to the above [1], wherein the resin layer precursor forming step (A), the surface treatment step (B), and the winding step (C) are carried out continuously while transporting the substrate.
[5] After the resin layer precursor forming step (A),
A semi-curing step (P) is performed to semi-cure the resin layer precursor;
The method for producing a laminate according to any one of the above [1] to [4], further comprising the step of performing a surface treatment (B).
[6] The method for producing a laminate according to any one of the above [1] to [5], wherein the surface treatment is any one of chemical vapor deposition, physical vapor deposition, and plasma treatment.
[7] The method for producing a laminate according to any one of [1] to [6] above, wherein the temperature of the film in the surface treatment step (B) is 30°C or higher and 120°C or lower.
[8] The curable resin composition is a thermosetting resin composition,
[8] The method for producing a laminate according to any one of [1] to [7] above, wherein the ratio (number of isocyanate groups)/(number of hydroxyl groups) in the thermosetting resin composition is 10 or less.
[9] The method for producing a laminate according to any one of the above [1] to [8], wherein the unevenness on the outermost surface of the laminate includes a wrinkle structure.
[10] The method for producing a laminate described in any one of [1] to [9] above, wherein the wrinkle structure includes a primary wrinkle structure and a secondary wrinkle structure having a smaller undulation period than the primary wrinkle structure.
[11] The method for producing a laminate according to any one of the above [1] to [10], wherein the specific surface area (S/A) of the outermost surface of the laminate is 1.001 or more.
[12] The method for producing a laminate according to any one of [1] to [11] above, wherein the outermost surface of the laminate has an arithmetic mean roughness (Sa) of 20 nm or more.
[13] The method for producing a laminate according to any one of [1] to [12] above, wherein the outermost surface of the laminate has a maximum height Sz of 1000 nm or more.
[14] The method for producing a laminate according to any one of [1] to [13] above, wherein the absolute value of Ssk (degree of deviation) of the outermost surface of the laminate is 20 or less.
[15] The method for producing a laminate according to any one of the above [1] to [14], wherein the thickness (tb) of the resin layer is 0.1 μm or more and 15 μm or less.
[16] The method for producing a laminate according to any one of [1] to [15] above, wherein a cover layer is formed by the dry process.
[17] The method for producing a laminate according to the above [16], wherein the cover layer is either an inorganic substance-containing layer or a cover resin layer.
[18] The method for producing a laminate according to the above [17], wherein the inorganic substance-containing layer is formed from at least one selected from the group consisting of diamond-like carbon, metal, metal oxide, metal nitride, metal carbide, and composites thereof.
[19] The method for producing a laminate according to any one of [16] to [18] above, wherein the thickness (ta) of the cover layer is 5 nm or more and 300 nm or less.
[20] The method for producing a laminate according to any one of the above [16] to [19], wherein the ratio (ta/tb) of the thickness of the cover layer (ta, unit: nm) to the thickness of the resin layer (tb, unit: μm) is 0.1 or more and 3500 or less.

The present invention makes it possible to continuously produce laminates with surface irregularities that are controllable and do not involve particle shedding.

1 is a schematic diagram illustrating an example of a laminate manufacturing apparatus according to a first embodiment of the present invention. 1 is a schematic diagram illustrating an example of a laminate manufacturing apparatus according to a first embodiment of the present invention. 1 is a schematic cross-sectional view showing an example of a laminate of the present invention. 1 is a schematic cross-sectional view showing an example of a laminate of the present invention. 1 is a schematic diagram illustrating an example of a laminate of the present invention. 1 is a schematic diagram illustrating an example of a laminate of the present invention. 1 is an image of the outermost surface of the laminate having irregularities in Example 1, observed at a magnification of 10,000 times using a scanning electron microscope (SEM). 1 is an image of the outermost surface of the laminate having irregularities in Example 2, observed at a magnification of 10,000 times using a scanning electron microscope (SEM). 1 is an image of the outermost surface of the laminate having irregularities in Example 3 observed with a scanning electron microscope (SEM) at a magnification of 10,000 times. 1 is an image of the outermost surface of the laminate having irregularities in Example 4 observed with a scanning electron microscope (SEM) at a magnification of 10,000 times. 1 is an image of the outermost surface of the laminate having irregularities in Example 4, observed at a magnification of 50,000 times using a scanning electron microscope (SEM). 1 is an image of the outermost surface of the laminate having irregularities in Example 5, observed at a magnification of 10,000 times using a scanning electron microscope (SEM). 1 is an image of the outermost surface of the laminate having irregularities in Example 5, observed at a magnification of 50,000 times using a scanning electron microscope (SEM). 1 is an image of the outermost surface of the laminate having irregularities in Example 6, observed at a magnification of 10,000 times using a scanning electron microscope (SEM). 1 is an image of the outermost surface of the laminate having irregularities in Example 7, observed at a magnification of 10,000 times using a scanning electron microscope (SEM). 1 is an image of the outermost surface of the laminate having irregularities in Example 8, observed at 10,000 times magnification using a scanning electron microscope (SEM). 10 is an image of the outermost surface of the laminate having irregularities in Example 9, observed at 10,000 times magnification using a scanning electron microscope (SEM).

Next, the present invention will be described in detail based on the embodiments of the present invention. However, the present invention is not limited to the embodiments described below.

<<Method of manufacturing laminate>>
The method for producing a laminate of the present invention (hereinafter also referred to as "the present production method") includes at least a resin layer precursor forming step (A) of applying a curable resin composition to at least one surface of a substrate to obtain a substrate with a resin layer precursor; a surface treatment step (B) of performing a surface treatment by a dry process on the semi-cured or uncured substrate with the resin layer precursor to obtain a laminate having irregularities on the outermost surface; and a winding step (C) of winding up the laminate into a roll.
This manufacturing method can form a textured structure without using particles, eliminating the risk of particle shedding and enabling the laminate to be used in a wider range of applications. Furthermore, because the manufacturing method performs surface treatment continuously while the film is being transported, it offers higher productivity than conventional batch processing.

In the present manufacturing method, after the resin layer precursor forming step (A), a semi-curing step (P) of semi-curing the resin layer precursor may be carried out, and then the surface treatment step (B) may be carried out.
In the present manufacturing method, the cover layer is preferably formed by a dry process.

The materials for the substrate, resin layer, and cover layer used in the present invention, as well as each process, are described in detail below. Note that in the present invention, the resin layer prior to surface treatment by a dry process may be referred to as the "resin layer precursor."

<Base material>
The substrate in the present invention is not particularly limited as long as it is flexible and can be wound up, and examples of the material include organic substances such as resins, inorganic substances such as metals and metal oxides, and organic-inorganic composites. Examples of the substrate shape include sheets, films, and substrates. Among these, from the viewpoint of continuous productivity, the substrate shape is preferably a film, and a resin film is preferred because it is lightweight and easy to handle.

[Resin film]
The resin film used as the substrate is not limited in material and structure as long as it has necessary and sufficient rigidity. The resin film may have a single layer structure or a multilayer structure. When the resin film has a multilayer structure, it may have a two-layer or three-layer structure, or may have four or more layers as long as the effects of the present invention are not impaired.

Examples of resins used in the resin film include polyester, polyarylates, polyethersulfone, polycarbonate, polyetherketone, polysulfone, polyphenylene sulfide, polyester-based liquid crystal polymer, triacetyl cellulose, cellulose derivatives, polypropylene, polyamides, polyimide, polycycloolefins, etc. These resins may be used alone or in combination of two or more in the resin film.
When the resin film is multi-layered, the resins constituting the layers may be different from each other or may be the same as each other. The resin film may be a single layer or a multi-layered film, with each layer being constituted by a combination of two or more of the above resins.

Whether the resin film has a single layer structure or a multi-layer structure, it is preferably a polyester film in which the main component resin of each layer is polyester.
In this case, the term "main component resin" refers to the resin that is contained in the polyester film in the largest proportion, for example, a resin that accounts for 50% by mass or more, preferably 70% by mass or more, and more preferably 80% by mass or more (including 100% by mass) of the resins that constitute the polyester film.
As long as each layer of the resin film contains polyester as the main resin component, it may contain a resin other than polyester or a component other than resin.

The polyester may be a homopolyester or a copolymer polyester. In the case of a homopolyester, it is preferably one obtained by polycondensation of an aromatic dicarboxylic acid and an aliphatic glycol. Examples of the aromatic dicarboxylic acid include terephthalic acid and 2,6-naphthalenedicarboxylic acid. Examples of the aliphatic glycol include ethylene glycol, diethylene glycol, and 1,4-cyclohexanedimethanol.

On the other hand, examples of the dicarboxylic acid component of the copolymer polyester include one or more of isophthalic acid, phthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, and sebacic acid, and examples of the glycol component include one or more of ethylene glycol, diethylene glycol, propylene glycol, butanediol, 4-cyclohexanedimethanol, and neopentyl glycol.

Specific examples of polyester include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), and polybutylene naphthalate (PBN). Of these, PET and PEN are preferred, with PET being more preferred.

The resin film may contain particles for the purpose of forming a fine uneven structure on the film surface to impart various functions and for the main purpose of preventing scratches from occurring in each process.
The type of particles is not particularly limited as long as they are particles that can impart lubricity. Examples include inorganic particles such as silica, calcium carbonate, magnesium carbonate, barium carbonate, calcium sulfate, calcium phosphate, magnesium phosphate, kaolin, aluminum oxide, and titanium oxide, and organic particles such as acrylic resin, styrene resin, urea resin, phenolic resin, epoxy resin, and benzoguanamine resin. These may be used alone or in combination of two or more. Furthermore, precipitated particles obtained by precipitating and finely dispersing a part of a metal compound such as a catalyst in a process for producing a resin component such as polyester may also be used.
The shape of the particles is not particularly limited. For example, they may be spherical, lumpy, rod-like, flat, or the like. Furthermore, the hardness, specific gravity, color, and the like of the particles are also not particularly limited. Two or more types of these particles may be used in combination as needed.

The average particle size of the above particles is preferably 5 μm or less, more preferably 0.01 μm to 3 μm, and even more preferably 0.5 μm to 2.5 μm. Setting the particle size to 5 μm or less prevents the surface roughness of the resin film from increasing, making it less likely that problems will occur when forming the resin layer and cover layer.

The particle content is preferably 5% by mass or less, more preferably 0.0003% by mass or more and 3% by mass or less, and even more preferably 0.01% by mass or more and 2% by mass or less, based on 100% by mass of the resin film. By keeping the particle content within this range, it is possible to achieve both smoothness and transparency in the film.

There are no particular limitations on the method for adding particles to a resin film, and any conventionally known method can be used. For example, they can be added during the process of producing the resin component. For example, in the case of a polyester film, they can be added at any stage in the polyester production process. Preferably, they are added after the esterification or transesterification reaction is complete.

If necessary, conventionally known antioxidants, antistatic agents, heat stabilizers, lubricants, dyes, pigments, UV absorbers, etc. can be added to the resin film.

The thickness of the resin film is not particularly limited as long as it is within the range that allows it to be formed into a film, but it is preferably 12 μm or more and 250 μm or less, more preferably 25 μm or more and 250 μm or less, and even more preferably 50 μm or more and 200 μm or less.

Resin films can be formed, for example, by forming a resin composition into a film using a melt casting method or a solution casting method. In the case of a multilayer structure, co-extrusion may be used. Furthermore, the film may be uniaxially or biaxially stretched, with biaxially stretched films being preferred from the perspective of rigidity.

[Substrates other than resin]
The substrate other than resin is not particularly limited as long as the resin layer described below can be fixed onto the substrate, but examples thereof include metals, semi-metals, ceramics, and composite materials.
Examples of metals include aluminum, copper, silver, gold, iron, and nickel. These metals may be used alone or in the form of an alloy, and preferred examples include aluminum, copper, and SUS, a steel-based material.
Examples of semimetals include silicon and germanium, and these semimetals may be used alone or in the form of an alloy.
Examples of ceramics include inorganic solid materials such as oxides, carbides, nitrides, and borides, and preferably glass.
A composite material is a material that is an integral combination of two or more different materials, such as resin, metal, semi-metal, and ceramic, and examples thereof include glass fiber reinforced plastic, carbon fiber reinforced plastic, and nanocomposite material.

<Resin layer>
The resin layer in the present invention is a cured product formed by curing a curable resin composition. When the curable resin composition is cured, it can easily adhere to a substrate, a cover layer, etc. Furthermore, in this manufacturing method, if the resin layer is left in an uncured or semi-cured state and subjected to a surface treatment by a dry process, it can buckle in response to a compressive stress acting along the surface direction, forming a wrinkled structure.
The curable resin composition in the present invention is preferably a heat- or active energy ray-curable resin composition. A heat-curable resin composition is more preferable in that it is easy to control the uneven structure of the laminate. Furthermore, an active energy ray-curable resin composition is more preferable in that the semi-curing step (P) can be easily performed in a short time.

[Thermosetting resin composition]
When the curable resin composition is a thermosetting resin composition, the thermosetting resin composition preferably contains a binder resin, more preferably contains a binder resin and a curing agent. By containing the binder resin and the curing agent, the thermosetting resin composition ensures adhesion to a substrate, a cover layer, etc., and is prone to buckling when a compressive stress is applied, making it prone to forming a wrinkled structure.

(binder resin)
The binder resin is a thermosetting resin that can be cured by heating, and when the thermosetting resin composition contains a curing agent, it is a resin that cures in the presence of the curing agent.
Examples of the binder resin include polyester resin, urethane resin, acrylic resin, vinyl alcohol resin, ethylene vinyl alcohol resin, vinyl-modified resin, oxazoline group-containing resin, carbodiimide group-containing resin, epoxy group-containing resin, isocyanate group-containing resin, alkoxyl group-containing resin, modified styrene resin, and modified silicone resin, and these can be used alone or in combination of two or more. The binder resin may be reacted with another binder resin to form a resin layer.
Among these, from the viewpoints of adhesion to the substrate or to the substrate and the cover layer, and hot water resistance, it is preferable to use at least one resin selected from polyester resins, urethane resins, acrylic resins, epoxy group-containing resins, and alkoxyl group-containing resins, either alone or in combination of two or more, and acrylic resins are more preferable.
The binder resin may be any resin capable of thermal crosslinking, such as urethane curing or epoxy curing, and from the viewpoint of reactivity with an isocyanate compound that is preferably used as a curing agent, as described below, a resin having a hydroxyl group, a carboxyl group, or an amino group is preferred, and a resin having a hydroxyl group is more preferred.
Among these, polyols having two or more hydroxyl groups in one molecule are preferred, and acrylic polyols are particularly preferred.

Examples of acrylic resins include (meth)acrylic polymers obtained by polymerizing polymerizable monomers including (meth)acrylic monomers. The (meth)acrylic polymers may be homopolymers or copolymers, or may be copolymers with polymerizable monomers other than (meth)acrylic monomers.
The (meth)acrylic monomer is a monomer having a (meth)acryloyl group. The polymerizable monomer other than the (meth)acrylic monomer is a monomer having a polymerizable functional group, and the polymerizable functional group may be a functional group containing a carbon-carbon unsaturated bond other than a (meth)acryloyl group, such as a vinyl group.
In this specification, when the expression "(meth)acryloyl group" is used, it means one or both of "acryloyl group" and "methacryloyl group", and the same applies to other similar terms.

Examples of the polymerizable monomer include alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, amyl (meth)acrylate, isoamyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, pentadecyl (meth)acrylate, and dodecyl (meth)acrylate; cyclic alkyl (meth)acrylates such as cyclohexyl (meth)acrylate and isobornyl (meth)acrylate; and hydrocarbon (meth)acrylates in which the portion other than the polymerizable functional group is composed of a hydrocarbon, such as (meth)acrylates having an aromatic ring, such as phenyl (meth)acrylate.
Among these, alkyl (meth)acrylates or cyclic alkyl (meth)acrylates are preferred, with methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and cyclohexyl (meth)acrylate being more preferred, and methyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and cyclohexyl (meth)acrylate being even more preferred.
In the (meth)acrylic polymer, the hydrocarbon (meth)acrylate-derived structural unit preferably accounts for, for example, 20% by mass or more and 90% by mass or less, or 30% by mass or more and 80% by mass or less.

As the polymerizable monomer, a monomer component other than a hydrocarbon-based (meth)acrylate may be used, and specifically, it is preferable to use a hydroxyl group-containing monomer. Examples of the hydroxyl group-containing monomer include hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate. Note that the hydroxyl group referred to in the hydroxyl group-containing monomer is a hydroxyl group that is not directly bonded to an aromatic ring. Among these, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 2-hydroxybutyl (meth)acrylate are preferred.
The hydroxyl group-containing monomer is preferably used in combination with the hydrocarbon (meth)acrylate, and therefore the acrylic resin is preferably a (meth)acrylic copolymer obtained by copolymerizing a hydrocarbon (meth)acrylate with a hydroxyl group-containing monomer, or a (meth)acrylic copolymer obtained by copolymerizing a hydrocarbon (meth)acrylate with a hydroxyl group-containing monomer and a monomer component other than these (other monomer component). This allows the (meth)acrylic copolymer to be an acrylic polyol containing multiple hydroxyl groups.
In the (meth)acrylic polymer, the content of structural units derived from hydroxyl group-containing monomers is, for example, preferably from 0.5% by mass to 80% by mass, and more preferably from 1% by mass to 70% by mass.

As the polymerizable monomer, a monomer component (other monomer component) other than hydrocarbon-based (meth)acrylates and hydroxyl group-containing monomers may be used. Specifically, carboxyl group-containing monomers such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid, and citraconic acid; amino group-containing monomers such as dimethylaminoethyl (meth)acrylate, dimethylaminoethyl (meth)methacrylate, and diethylaminoethyl (meth)acrylate; glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether, and α-methyl-o-vinylbenzyl glycidyl alkylene glycol monoalkyl ether (meth)acrylates such as ethylene glycol monomethyl ether acrylate and ethylene glycol monomethyl ether methacrylate; acrylamide compounds such as (meth)acrylamide, diacetone acrylamide and N-methylolacrylamide; (meth)acrylonitrile; styrene derivatives such as styrene, α-methylstyrene, divinylbenzene and vinyltoluene; and various vinyl halides such as vinyl chloride and vinylidene chloride.
Furthermore, as the polymerizable monomer, a monomer having a functional group with an ultraviolet absorbing function may be used from the viewpoint of improving the light resistance of the resin layer, etc. Specific examples include monomers having an ultraviolet absorbing functional group such as a benzotriazole skeleton, a benzophenone skeleton, a triazine skeleton, or a hindered amine skeleton, and a polymerizable functional group such as a (meth)acryloyl group.

The content of structural units derived from other monomer components (monomer components other than hydrocarbon (meth)acrylates and hydroxyl group-containing monomers) in the (meth)acrylic polymer is, for example, 50% by mass or less, preferably 40% by mass or less. The lower limit is not particularly limited, and may be 0% by mass or more.
It should be noted that each of the above-mentioned monomer components (hydrocarbon (meth)acrylate, hydroxyl group-containing monomer, and other monomer components) is preferably a monofunctional monomer having one polymerizable functional group in the molecule, as exemplified above, but may also appropriately contain a polyfunctional monomer having two or more polymerizable functional groups within a range that does not impair the effects of the present invention.

(hardening agent)
As the curing agent, any compound capable of reacting with the binder resin and curing may be used, but from the viewpoint of curability with the binder resin, an isocyanate compound is preferred.

The isocyanate compound is preferably an aromatic or aliphatic diisocyanate or a trivalent or higher polyisocyanate. Examples of the isocyanate compound that can be used include tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, cyclohexane diisocyanate, dicyclohexyl diisocyanate, and trimers thereof.
Alternatively, a terminal isocyanate group-containing compound obtained by reacting an excess amount of any of these isocyanate compounds with a low-molecular-weight active hydrogen compound such as ethylene glycol, propylene glycol, trimethylolpropane, glycerin, sorbitol, biuret, cyanuric acid, ethylenediamine, monoethanolamine, diethanolamine, or triethanolamine, or an active hydrogen polymer compound such as polyester polyol, polyether polyol, or polyamide, may be used.

(Preferred form of thermosetting resin composition)
When the resin layer is formed from a thermosetting resin composition, the resin layer preferably contains a resin having a urethane bond and/or a urea bond. The use of a resin having a urethane bond and/or a urea bond ensures flexibility and makes the resin layer more susceptible to buckling due to compressive stress generated when the surface is treated by a dry process.
The urethane bond and urea bond are preferably formed by at least one of the reactions between the binder resins, the curing agent, and the binder resin and the curing agent, and more preferably by the reaction between the binder resin and the curing agent. Forming a urethane bond and/or urea bond by such a reaction facilitates improving the adhesion of the resin layer to the cover layer, substrate, etc.

From the viewpoints of accelerating the curing with the binder resin, the adhesion of the resin layer to the cover layer and substrate, and ease of forming a secondary wrinkle structure, it is preferable to use an isocyanate compound as the curing agent.
When both a binder resin and a curing agent are used as the thermosetting resin composition, it is preferable to use an isocyanate compound as the curing agent and a polyol as the binder resin, and when an acrylic resin is used as the binder resin, it is preferable that the acrylic resin is an acrylic polyol containing multiple hydroxyl groups in one molecule.

By adjusting the compounding ratio of the binder resin and the curing agent, it is possible to control the shape of the wrinkle structure described below.
When an isocyanate compound is used as the curing agent and a polyol is used as the binder resin, the smaller the amount of polyol relative to the isocyanate compound, the longer the fluidity of the thermosetting resin composition is maintained during curing, making it easier to form a high-order wrinkle structure.
From the above viewpoints, R ((the number of isocyanate groups in the curing agent)/(the number of hydroxyl groups in the binder resin)) in the thermosetting resin composition is preferably 0.1 or more, more preferably 0.5 or more, even more preferably 1 or more, and even more preferably 1.3 or more.
Furthermore, the thermosetting resin composition may not contain a binder resin, i.e., the number of hydroxyl groups may be 0 (R = ∞). From the viewpoint of reducing tackiness in a semi-cured or uncured state, R is preferably 10 or less, more preferably 5 or less, and even more preferably 3 or less.

The above R in the resin layer can be determined by combining analytical methods such as NMR, pyrolysis GC/MS, and TOF-SIMS. More specifically, first, unreacted curing agent is extracted from the cured resin layer, and the parent structure of the curing agent and the number of isocyanate groups (valence) are identified using the above analytical method. Then, the structure of the monomers that make up the binder resin and the number of hydroxyl groups (valence) are identified from the cured resin layer using the above analytical method, and R can be determined from the ratio of the parent structure of the curing agent to the monomers that make up the binder resin and their respective valences.

When a thermosetting resin composition contains an excess of isocyanate compound relative to polyol (R exceeds 1), the cured resin layer will have urethane bonds formed by the reaction between the polyol and the isocyanate compound, and urea bonds formed from the excess isocyanate compound. Therefore, the above R can also be determined from the ratio of urethane bonds to urea bonds in the cured resin layer using solid-state NMR, FT-IR, etc.

[Active energy ray-curable resin composition]
(Photopolymerizable compound)
When the curable resin composition is an active energy ray-curable resin composition, the active energy ray-curable resin composition contains a photopolymerizable compound. The photopolymerizable compound is a compound that can be polymerized by irradiation with active energy rays. Details of the active energy rays are as described in the production method described below.
The resin component of the resin layer formed from the active energy ray-curable resin composition may be a mixture of a prepolymer such as epoxy (meth)acrylate, urethane (meth)acrylate, polyester (meth)acrylate, or acrylic (meth)acrylate with a photopolymerizable monomer, or the photopolymerizable monomer may be used alone.

The photopolymerizable monomer is not particularly limited as long as it is a compound having a radical polymerizable group, and examples thereof include polyfunctional photopolymerizable monomers. The number of radical polymerizable groups contained in one molecule of the polyfunctional photopolymerizable monomer is not particularly limited, as long as it is two or more.
The radical polymerizable group includes functional groups containing a carbon-carbon unsaturated bond, such as a (meth)acryloyl group and a vinyl group, and among these, a (meth)acryloyl group is preferred.

Examples of the photopolymerizable monomer include polyfunctional (meth)acrylates having an aromatic ring. Specifically, polyfunctional (meth)acrylates having a benzene ring, a naphthalene ring, an anthracene ring, a fluorene ring, a phenanthrene ring, a phenalene ring, or the like are preferred. Among these, fluorene-based polyfunctional (meth)acrylates having a fluorene ring are preferred.
Examples of fluorene-based polyfunctional (meth)acrylates include 9,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl]fluorene, 9,9-bis[4-(2-(meth)acryloyloxyethoxy)-3-methylphenyl]fluorene, 9,9-bis[4-(2-(meth)acryloyloxypropoxy)-3-methylphenyl]fluorene, and 9,9-bis[4-(2-(meth)acryloyloxyethoxy)-3,5-dimethylphenyl]fluorene. , 9,9-bis[4-((meth)acryloyloxypoly(ethyleneoxy))phenyl]fluorene, 9,9-bis[4-((meth)acryloyloxypolyethyleneoxy)-3-methylphenyl]fluorene, 9,9-bis[4-((meth)acryloyloxypoly(propyleneoxy))-3-methylphenyl]fluorene, 9,9-bis[4-((meth)acryloyloxypoly(ethyleneoxy))-3,5-dimethylphenyl]fluorene, and the like.

Furthermore, as the photopolymerizable monomer, various polyfunctional (meth)acrylates other than polyfunctional (meth)acrylates having an aromatic ring can be used, and examples thereof include aliphatic polyfunctional (meth)acrylates such as ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, butanediol di(meth)acrylate, hexanediol di(meth)acrylate, nonanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and tricyclodecane dimethanol di(meth)acrylate.
The above-mentioned photopolymerizable monomers may be used alone or in combination of two or more.
Among the above, polyfunctional (meth)acrylates having an aromatic ring are preferred, and polyfunctional (meth)acrylates having an aromatic ring may be used in combination with other photopolymerizable compounds.
The photopolymerizable monomer may be used alone or in combination with a monofunctional photopolymerizable compound described below.

The photopolymerizable monomer is not limited to a polyfunctional one, and may be a monofunctional photopolymerizable monomer. The monofunctional photopolymerizable monomer may be used alone, or may be used in combination with a polyfunctional photopolymerizable monomer as described above.
Examples of the monofunctional photopolymerizable monomer include alkyl (meth)acrylate, cyclic alkyl (meth)acrylate, (meth)acrylate having an aromatic ring, hydroxyl group-containing monomer, carboxyl group-containing monomer, amino group-containing monomer, epoxy group-containing monomer, acrylamide-based compound, (meth)acrylonitrile, styrene derivative, vinyl halide, etc. Specific examples of these compounds include those exemplified for the (meth)acrylic polymer described above.

(Photopolymerization initiator)
When the curable resin composition contains a photopolymerizable compound, it preferably further contains a photopolymerization initiator, which makes it possible to easily cure the resin layer precursor by irradiating the resin layer precursor with active energy rays, as described below.
Examples of photopolymerization initiators include benzil, benzophenone and derivatives thereof, thioxanthones, benzil dimethyl ketals, α-hydroxyalkylphenones, α-hydroxyacetophenones, hydroxyketones, aminoalkylphenones, acylphosphine oxides, oxime ester compounds, etc. Among these, α-hydroxyalkylphenones are preferred because they are less likely to yellow during curing and can give transparent cured products.
The content of the photopolymerization initiator is preferably in the range of 0.05 to 5 parts by mass, more preferably 0.2 to 3 parts by mass, relative to 100 parts by mass of the curable resin composition. When the content of the photopolymerization initiator is 0.05 parts by mass or more, the desired initiation effect can be obtained, and when the content of the photoinitiator is 5 parts by mass or less, the curable resin composition is not over-cured by irradiation with active energy rays, and is more likely to remain in a semi-cured state.

In the above explanation, the curable resin composition has been described as being either heat-curable or actinic energy ray-curable, but it may also be a heat- and actinic energy ray-curable resin composition that can be cured by both heat and actinic energy rays. In this case, the curable resin composition preferably contains both a binder resin and a photopolymerizable compound.

The curable resin composition may optionally contain antifoaming agents, coatability improvers, thickeners, organic lubricants, UV absorbers, antioxidants, foaming agents, dyes, pigments, inorganic particles, organic particles, etc., within the scope of the present invention. These additives may be used alone, or two or more types may be used in combination as needed.

[Resin layer thickness]
The thickness (tb) of the resin layer can be adjusted according to the step of the unevenness to be formed and the application, but is not limited thereto. It is preferably 0.1 μm or more and 15 μm or less. If it is 15 μm or less, peeling from the substrate due to the internal stress of the resin layer itself can be prevented. If it is 0.1 μm or more, the thickness of the resin layer can be maintained uniform, and a certain level of roughness can be ensured by the wrinkle structure. From this perspective, the thickness (tb) of the resin layer is more preferably 0.5 μm or more, even more preferably 1 μm or more, and even more preferably 1.2 μm or more, and is preferably 10 μm or less, more preferably 7 μm or less.
The thickness of the resin layer and the cover layer described later can be determined by measuring the maximum thickness (peak of a convex portion) and the minimum thickness (valley of a concave portion) by measuring the step using a micro-profile measuring instrument or by observing the cross section using a scanning electron microscope (SEM) and/or a transmission electron microscope (TEM), and then calculating the average value of these.

<Cover layer>
In the present invention, it is preferable to form a cover layer on the resin layer, which can impart properties such as water repellency, oil repellency, and hydrophilicity to the outermost surface of the laminate.
The cover layer may be formed on the resin layer so as to be in direct contact with the resin layer. Specific examples of the cover layer include an inorganic substance-containing layer and a cover resin layer. Of these, an inorganic substance-containing layer is preferred.

[Inorganic substance-containing layer]
The inorganic substance-containing layer is a layer formed from an inorganic substance and containing an inorganic substance as a main component. "Containing an inorganic substance as a main component" means that the inorganic substance accounts for 50% by mass or more of the inorganic substance-containing layer, preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more, and most preferably 100% by mass. The inorganic substance-containing layer is preferably formed from an inorganic substance that has good adhesion to the resin layer. Furthermore, the inorganic substance-containing layer is preferably formed using a material that can be easily formed on the resin layer by a dry process.

The inorganic material-containing layer is preferably formed from at least one inorganic material selected from diamond-like carbon (DLC), metal, metal oxide, metal nitride, metal carbide, or a composite thereof, where the metal includes so-called semimetals such as silicon, boron, and germanium.
In the inorganic substance-containing layer, examples of the metal constituting the metal, metal oxide, metal nitride, metal carbide, or composite thereof include silicon, aluminum, zinc, titanium, niobium, gold, silver, copper, indium, tin, and nickel, and among these, silicon and niobium are preferred, and silicon is more preferred.

The inorganic material used in the inorganic-containing layer is preferably at least one selected from silicon-based compounds such as silicon, silicon oxide, silicon nitride, silicon oxynitride, silicon oxide carbide, silicon oxycarbonitride, silicon carbide, fluorine-containing silicon oxide, and fluorine-containing silicon carbide; aluminum-based compounds such as aluminum oxide, aluminum nitride, aluminum oxynitride, and aluminum oxide carbide; niobium-based compounds such as niobium oxide; zinc-based compounds such as zinc oxide; titanium-based compounds such as titanium oxide; diamond-like carbon, fluorine-containing diamond-like carbon; and conductive oxides such as ITO and IZO.

From the viewpoint of increasing the hardness of the laminate and improving its durability, the inorganic-containing layer is preferably a layer containing at least one of the inorganic materials listed above: diamond-like carbon (DLC), silicon, silicon oxide, niobium oxide, silicon carbide oxide, and silicon carbide; more preferably a layer containing at least one of DLC, silicon, and silicon oxide; and even more preferably a layer containing either silicon or silicon oxide.

[Cover resin layer]
The cover resin layer is preferably formed on the resin layer by a dry process. The cover resin layer is a layer formed from a resin component and contains the resin component as a primary component. Here, "containing the resin component as a primary component" means that the resin component accounts for 50% by weight or more of the cover resin layer, preferably 70% by weight or more, preferably 80% by weight or more, preferably 90% by weight or more, and preferably 100% by weight.

The resin component used for the cover resin layer is preferably a resin component that can be formed on the resin layer by a dry process. Specific resin components include fluorine-based resins, polyethylene, polystyrene, etc., and among these, a fluorine-based resin layer formed from a fluorine-based resin is preferred. By using a fluorine-based resin, the cover resin layer can be easily formed on the resin layer by a dry process. Furthermore, by using a fluorine-based resin, when the cover resin layer is the outermost surface, it becomes easier to impart chemical resistance, slip properties, or liquid repellency to the laminate.
Examples of the fluorine-based resin include polytetrafluoroethylene and tetrafluoroethylene-ethylene copolymer.

[Formation of cover layer]
The cover layer does not necessarily have to be formed by a dry process. If the cover layer is not formed by a dry process, the concaves and convexes may be formed in the resin layer in advance by a separate dry process, and then the cover layer may be formed.
When the cover layer is formed by a process other than the dry process, inorganic substances and resin components used in the inorganic substance-containing layer and the cover resin layer may be other than those described above. Specifically, in addition to the resin components described above, the resin components exemplified below as resin components usable in the overcover layer may also be used.

[Cover layer thickness]
The thickness (ta) of the cover layer is preferably 5 nm or more and 300 nm or less. By setting the thickness (ta) of the cover layer within the above range, an appropriate film stress is generated when the film is formed by a dry process, which applies an appropriate compressive stress to the resin layer, making it easier to form a wrinkle structure with the desired roughness. From the viewpoint of making it easier to form the desired unevenness on the outermost surface of the laminate, the thickness (ta) of the cover layer is more preferably 10 nm or more and 250 nm or less, and even more preferably 20 nm or more and 200 nm or less.

[Thickness ratio of cover layer to resin layer (ta/tb)]
In the present invention, the ratio (ta/tb) of the thickness of the cover layer (ta, unit: nm) to the thickness of the resin layer (tb, unit: μm) is preferably 0.1 or more and 3500 or less. By setting the thickness ratio within the above range, when the cover layer is formed by a dry process, it becomes easier to form irregularities of the desired roughness by the dry process. Furthermore, if irregularities are formed on the surface of the resin layer before forming the cover layer, smoothing of the irregularities by the cover layer can be prevented. From the viewpoint of making it easier to form the desired irregularities on the outermost surface of the laminate, the thickness ratio (ta/tb) is more preferably 1 or more and 500 or less, even more preferably 2 or more and 400 or less, and even more preferably 5 or more and 250 or less.

<Manufacturing method according to the first embodiment>
In the manufacturing method according to the first embodiment of the present invention (hereinafter also referred to as the "first manufacturing method"), after the resin layer precursor forming step (A), the substrate with the resin layer precursor is wound into a roll and then unwound again to perform the surface treatment step (B).
That is, in the first manufacturing method, after the resin layer precursor forming step (A), a winding step (X) of winding the substrate with the resin layer precursor into a roll and an unwinding step (Y) of unwinding the substrate with the resin layer precursor from the roll are performed, and then a surface treatment step (B) is performed.
By winding up once before the surface treatment step (B), for example, when a treatment under reduced pressure is performed in the surface treatment step (B), it becomes easier to set up a reduced pressure environment, for example, to remove moisture contained in the substrate and the resin layer precursor in advance. Furthermore, by storing the resin layer precursor in a constant temperature environment after winding up, it is also possible to perform a semi-curing step (P) in which the resin layer precursor is semi-cured.

In the present production method, from the viewpoint of improving continuous productivity, it is preferable to carry out the surface treatment step (B) and the winding step (C) while transporting the substrate with the resin layer precursor.
The conveying speed in the surface treatment step (B) and the winding step (C) is preferably 0.1 m/min to 30 m/min, more preferably 0.2 m/min to 20 m/min, and even more preferably 10 m/min or less. By setting the conveying speed within the above range, the surface treatment can be sufficiently carried out while improving productivity, and unevenness including a wrinkle structure can be easily formed.

The resin layer precursor forming process (A), semi-curing process (P), winding process (X), unwinding process (Y), surface treatment process (B), and winding process (C) are described below. Note that, hereinafter, the substrate with resin layer precursor wound into a roll in the winding process (X) is also referred to as the "first wound body," and the laminate wound into a roll in the winding process (C) is also referred to as the "second wound body."

1. Resin layer precursor forming step (A)
In the resin layer precursor forming step (A), a curable resin composition is applied to at least one surface of a substrate to form a resin layer precursor.
The details of the substrate and the curable resin composition used in the resin layer precursor forming step (A) are as described above. The curable resin composition may be diluted with a solvent such as water or an organic solvent as needed. When diluted with a solvent such as water or an organic solvent, the amount (parts by mass, etc.) of the curable resin composition described above and the amount of each component constituting the composition are based on the solid content.
The organic solvent to be used is not particularly limited, and may be selected from the viewpoint of solubility, dispersibility, etc. depending on the composition of the curable resin composition. Examples of the organic solvent include alcohol-based solvents such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; ether-based solvents such as dimethyl glycol and ethylene glycol monoethyl ether; ester-based solvents such as ethyl acetate; acetate-based solvents such as propylene glycol monomethyl ether acetate; ketone-based solvents such as methyl isobutyl ketone and methyl ethyl ketone; aliphatic hydrocarbon-based solvents such as various alkanes; and aromatic hydrocarbon-based solvents such as toluene, xylene, and benzene.
The organic solvent may be one kind or two or more kinds, if necessary. The components constituting the curable resin composition may be dissolved in the solvent or may be dispersed in the solvent.
When the curable resin composition is diluted with water, an organic solvent, or the like, it is preferable to adjust the solid content concentration to, for example, about 0.1% by mass or more and 50% by mass or less, and preferably about 3% by mass or more and 40% by mass or less.

The curable resin composition can be applied to a substrate by any conventional coating method such as reverse gravure coating, direct gravure coating, roll coating, die coating, bar coating, curtain coating, spray coating, dip coating, or spin coating.
When the substrate is a resin film, the curable resin composition may be applied by in-line coating, which refers to applying the curable resin composition on the production line where the resin film is formed.
The solvent after application can be dried by heating in an oven or by drying without heating in a reduced pressure dryer.
The surface of the substrate to which the curable resin composition is to be applied may be previously subjected to a surface treatment such as a corona treatment, a plasma treatment, or a UV ozone treatment.

2. Semi-curing process (P)
In the semi-curing step (P), the resin layer precursor formed in the resin layer precursor forming step (A) is semi-cured.
In the first manufacturing method, the semi-curing step (P) is not essential, but it is preferable to perform the semi-curing step (P) from the viewpoint of improving the handleability of the substrate with the resin layer precursor and from the viewpoint of being able to control the wrinkle structure formed in the surface treatment step (B).
For example, if the resin layer precursor obtained in the resin layer precursor forming step (A) has strong tack and is difficult to handle, it is preferable to perform a semi-curing step (P) between the resin layer precursor forming step (A) and the winding step (X). However, if there are no problems in handling, this step (P) is not essential, and the resin layer precursor may be transported to the winding step (X) in an uncured state without being heated or irradiated with energy rays.
Furthermore, since the semi-cured state of the curable resin composition makes the resin layer precursor more susceptible to buckling due to surface treatment by a dry process, if it is desired to control the uneven structure, it is preferable to carry out the semi-curing step (P) between the winding step (X) and the unwinding step (Y), or between the unwinding step (Y) and the surface treatment step (B).

Here, semi-cured in the present invention refers to a state in which the curable resin composition is not completely cured, and refers to a state in which the curing of the curable resin composition further progresses when further irradiated with heat or energy rays.
Whether the curable resin composition is semi-cured or not can be confirmed, for example, by gently rubbing the surface of the resin layer precursor 50 times with a cotton swab soaked in a solvent and checking whether the surface of the substrate is exposed. If the curable resin composition is completely cured, the surface of the substrate will not be exposed even when the surface of the resin layer precursor is rubbed. The degree of semi-curing can be determined from the number of rubs at which the surface of the resin layer precursor begins to thin or the number of rubs until the surface of the substrate is exposed. It is preferable to use the same solvent in which the cotton swab is immersed as the solvent in which the curable resin composition is diluted.

When the curable resin composition has thermosetting properties, in the semi-curing step (P), the resin layer precursor formed in the resin layer precursor forming step (A) is semi-cured by heating. The method of semi-curing the resin layer precursor may be performed at room temperature, such as by natural drying, but from a practical standpoint, it is preferable to perform it by heating, such as by heat drying. In addition, when the solvent in the resin layer precursor forming step (A) is dried by heat drying, the drying of the solvent may also serve as the semi-curing step (P).
Furthermore, when the curable resin composition has active energy ray curability, in the semi-curing step (P), the resin layer precursor formed in the resin layer precursor-forming step (A) is semi-cured by irradiating the resin layer precursor with active energy rays. However, when a heat- and active energy ray-curable resin composition is used as the resin layer component, the resin layer precursor may be semi-cured only by heating or only by irradiating with active energy rays, or the resin layer precursor may be semi-cured by a combination of heating and active energy irradiation.

When semi-curing the resin layer precursor by heating, the heating temperature and heating time can be set depending on the components contained in the curable resin composition. For example, the resin layer precursor is heated at a temperature of 50°C or higher and 200°C or lower, preferably 70°C or higher and 150°C or lower, for a time of, for example, 3 seconds or higher and 30 minutes or lower, preferably 30 seconds or higher and 10 minutes or lower, and more preferably 40 seconds or higher and 5 minutes or lower.

Furthermore, when the resin layer precursor is semi-cured by irradiating it with active energy rays, the active energy rays that can be used include light rays such as far ultraviolet rays, ultraviolet rays, near ultraviolet rays, and infrared rays, electromagnetic waves such as X-rays and gamma rays, as well as electron beams, proton beams, and neutron beams. However, curing by ultraviolet irradiation is advantageous in terms of curing speed, ease of obtaining an irradiation device, cost, and the like.
When semi-curing the resin layer precursor by ultraviolet irradiation, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, a chemical lamp, an electrodeless discharge lamp, an LED lamp, or the like that emits light in a wavelength range of 150 to 450 nm may be used. The ultraviolet light may be irradiated to an extent that the resin layer precursor is semi-cured, and the irradiation amount is not particularly limited, but the ultraviolet light may be irradiated with an integrated light amount of, for example, 0.5 to 5000 mJ/cm ² , preferably about 1 to 2000 mJ/cm ² .

In this embodiment, a surface treatment is performed by a dry process on a resin layer precursor that has not yet been sufficiently cured. Therefore, in order to stably form a wrinkled structure, it is preferable to adjust the time and storage temperature between the resin layer precursor forming step (A) and the surface treatment step (B) (for example, between the winding step (X) and the unwinding step (Y)).
The interval between the resin layer precursor forming step (A) and the surface treatment step (B) (i.e., the time from the end of heating and/or active energy ray irradiation to the start of surface treatment by the dry process) is not particularly limited as long as the resin layer precursor is in a desired semi-cured state when the surface treatment is started, but is, for example, 3 days or less, preferably 2 days or less, and more preferably 24 hours or less. The lower limit of the interval is not particularly limited, and may be 0 minutes or more.
The interval between the resin layer precursor forming step (A) and the surface treatment step (B) is not particularly limited, but the substrate on which the resin layer precursor has been formed may be left at a temperature of, for example, 0°C or higher and 60°C or lower, preferably 5°C or higher and 40°C or lower, and more preferably 5°C or higher and 30°C or lower.
Furthermore, when the interval time is long, the heating conditions, active energy ray irradiation conditions, etc. in the resin layer precursor forming step (A) may be appropriately selected, taking into consideration that curing progresses between the resin layer precursor forming step (A) and the surface treatment step (B).

3. Winding process (X)
In the winding step (X), the substrate with the resin layer precursor is wound around a core and wound into a roll to obtain a first wound body.
The core refers to a cylindrical winding core used for winding up the film. The material of the core is not particularly limited, but examples thereof include paper, resin-impregnated paper, acrylonitrile-butadiene-styrene copolymer (ABS resin), FRP, phenolic resin, and inorganic-containing resin. Among these, from the viewpoints of a small thermal expansion coefficient, high rigidity, low swelling due to humidity, and excellent winding properties, it is preferable to use a resin such as acrylonitrile-butadiene-styrene copolymer (ABS resin), FRP, phenolic resin, or inorganic-containing resin.
When the core material is paper, the desired properties can be easily obtained by coating the surface with a resin, etc. Furthermore, from the viewpoint of surface smoothness, it is also preferable that the core be a tube made of resin-impregnated paper.

The length of the substrate with resin layer precursor wound into a roll is not particularly limited, but is preferably 5 m or more, more preferably 10 m or more, and even more preferably 50 m or more. Furthermore, the length of the film is preferably 10,000 m or less. Having a film length of 5 m or more improves productivity.

The winding tension in the winding step (X) may be selected depending on the rigidity, width, and thickness of the substrate, but is preferably 10 to 500 N from the viewpoint of preventing the wound body from slipping.

4. Unwinding process (Y)
In the unwinding step (Y), the substrate with the resin layer precursor is unwound from the roll (first wound body). The unwound substrate with the resin layer precursor may be transported as is to be subjected to the semi-curing step (P) or the surface treatment step (B), or may be slit to a width suitable for the subsequent step or shortened in length.
When the length of the substrate with the resin layer precursor is shortened, it is preferably 5 m or more and 5,000 m or less, more preferably 10 m or more and 1,000 m or less, and even more preferably 50 m or more, from the viewpoint of facilitating continuous performance of the surface treatment step (B) described later.

5. Surface treatment step (B)
In the surface treatment step (B), the substrate with the semi-cured or uncured resin layer precursor is subjected to a surface treatment by a dry process. By performing the surface treatment by a dry process while the resin layer precursor is in a semi-cured or uncured state, unevenness including a wrinkle structure can be formed.
The dry process is a method of performing a surface treatment on a semi-cured or uncured resin layer precursor under reduced pressure or in vacuum.

In the surface treatment step (B), a cover layer may be formed by a dry process, but a dry process treatment without forming a film may also be performed without forming a cover layer.
The wrinkle structure may have a high-order wrinkle structure as described below, and the high-order wrinkle structure is preferably formed in the surface treatment step (B).

In this embodiment, the principles by which the unevenness including the wrinkle structure is formed by the surface treatment using the dry process, and the principles by which the high-order wrinkle structure is formed are not clear, but are presumed to be as follows.
When a cover layer is formed on a semi-cured or uncured resin layer precursor by a dry process, it is believed that the resin layer precursor receives energy from the dry process (light from plasma, radiant heat, electrons and ions, or energy from incident particles) and hardens. During this process, the resin layer precursor receives energy from the dry process and hardens, shrinks, and loses fluidity as it heats up, while the cover layer grows and generates film stress. During this process, compressive stress increases along the surface of the resin layer precursor, and it is believed that buckling occurs when the resin layer precursor can no longer resist the compressive stress, resulting in the formation of a wrinkled structure.
Furthermore, even in the case of a dry process that does not form a cover layer or involve film deposition, it is estimated that the energy from the dry process treatment similarly generates compressive stress along the surface direction in the resin layer precursor, and when the resin layer precursor can no longer resist the compressive stress, buckling occurs and a wrinkle structure is formed.
It is to be noted that when forming the cover layer, if the film stress generated during the deposition of the cover layer is large, the first buckling will occur at an early stage, generating large swells (primary wrinkle structure), and then, when the resin fluidity has slightly decreased, the second buckling will occur, generating small swells (secondary wrinkle structure).

The size of the waviness in the wrinkle structure (i.e., surface roughness (Sa, Sz), specific surface area S/A, etc.) is presumed to vary depending on the balance between the thickness of the resin layer and the cover layer, the hardness of the resin layer precursor in a semi-cured or uncured state, and the resin fluidity. Therefore, the size of the waviness can be adjusted by appropriately changing the thickness of the resin layer and the cover layer, the components contained in the resin layer and the cover layer, the curing conditions, etc.
Furthermore, the surface treatment by the dry process promotes the curing of the resin layer precursor as described above, and the surface treatment step (B) may, for example, fully cure the resin layer. Here, fully cured means a state in which the curing does not substantially proceed even when the resin layer is heated or irradiated with active energy rays.

In this manufacturing method, it is preferable to form the cover layer by surface treatment using a dry process. When the cover layer is formed by surface treatment using a dry process, membrane stress occurs as described above, making it easier to form a wrinkle structure, and even a high-order wrinkle structure can be formed. Furthermore, by forming the cover layer by surface treatment using a dry process, the cover layer can be formed while forming the unevenness including the wrinkle structure in the surface treatment step (B), thereby simplifying the process.
Whether or not a dry process has been performed can be determined by observing the cross section with an SEM and/or a TEM. For example, if the cover layer is made of a crystalline material, if the crystal grain size changes in the thickness direction of the cover layer, it can be determined that a dry process has been performed. As the film formation by the dry process progresses, the crystal nuclei generated on the surface of the resin layer grow and the grain size gradually increases, so the crystal grain size at the surface of the cover layer tends to be largest and to become smaller as it approaches the resin layer.
On the other hand, such changes in crystal grain size are not observed when wet processing is used, in which a solvent is applied. In wet processing, the solvent evaporates during the drying process of the coating, which tends to create tiny voids throughout the thickness of the cover layer, resulting in a low-density film.

When the cover layer is formed by surface treatment using a dry process, examples of the surface treatment using the dry process include chemical vapor deposition (CVD) and physical vapor deposition (PVD).
The dry process is preferably a treatment carried out in a vacuum or under reduced pressure. When the surface treatment is carried out in a vacuum or under reduced pressure, the semi-cured or uncured resin layer precursor is placed in an oxygen-poor atmosphere, which facilitates curing by the dry process. Therefore, when the dry process is carried out in a vacuum or under reduced pressure, a wrinkle structure is likely to form. In particular, in the case of an active energy ray-curable resin composition, oxygen inhibition, which hinders radical polymerization, is suppressed, which facilitates crosslinking.
The pressure in a dry process carried out under vacuum or reduced pressure varies depending on the dry process technique, but is, for example, 15 Pa or less, preferably 10 Pa or less, and more preferably 1 Pa or less. The lower limit of the pressure in the dry process is not particularly limited, but is, for example, 1×10 ⁻⁷ Pa, taking into account the performance limits of each device.
When the cover layer is formed by a dry process, the film may be heated, preferably at a temperature of 30° C. or higher and 120° C. or lower, more preferably at a temperature of 40° C. or higher and 100° C. or lower. Heating the film increases the fluidity of the resin layer precursor, making it easier to form a high-order wrinkle structure.

[CVD]
The CVD method is not particularly limited, and includes plasma CVD, thermal CVD, cat-CVD (catalytic chemical vapor deposition), etc., with plasma CVD being preferred. Use of plasma CVD facilitates the formation of a wrinkled structure. From the viewpoint of facilitating the formation of a wrinkled structure, CVD is preferably carried out under reduced pressure, and the pressure when forming the cover layer is preferably 15 Pa or less, more preferably 1×10 ⁻² Pa to 10 Pa, and even more preferably 1×10 ⁻¹ Pa to 1 Pa, from the viewpoints of film formation rate and the ability to form a concave-convex structure.

When performing surface treatment by CVD, the output conditions for forming the cover layer are preferably 100 W or more and 1500 W or less, more preferably 300 W or more and 1200 W or less, and even more preferably 400 W or more and 1000 W or less, from the viewpoint of generating a necessary and sufficient film stress in the cover layer.
The thickness of the cover layer can be adjusted by known methods. For example, when plasma CVD is used, the thickness can be adjusted by adjusting the output, pressure of the raw material gas, concentration of the raw material gas, plasma generation time, etc.
When the surface treatment is carried out by CVD, the cover layer may be subjected to a crosslinking treatment by electron beam irradiation, if necessary, in order to improve water resistance and durability.

CVD is preferably used, for example, when forming inorganic-containing layers and cover resin layers, and is particularly suitable for forming inorganic-containing layers containing DLC as the inorganic substance, inorganic-containing layers containing silicon carbide and/or silicon oxide as the inorganic substance, and fluororesin layers containing fluororesins or the like as resin components.

For example, when forming an inorganic-containing layer containing DLC as the inorganic material by CVD, hydrocarbons or the like may be used as raw materials. Specific examples include alicyclic hydrocarbons represented by the formula _C4n+ 6H4n ₊₁₂ (n is an integer of 1 or greater), such as alicyclic hydrocarbons such as adamantane, diamantane, triamantane, pentamantane, and tetramantane; aromatic hydrocarbons such as benzene, toluene, and xylene; and aliphatic hydrocarbons such as acetylene, ethylene, propylene, methane, ethane, and propane. These raw materials may be used alone or in combination of two or more. Furthermore, the raw material gas may be diluted with a rare gas such as argon (Ar) or helium (He).

For example, when an inorganic substance-containing layer containing silicon as an inorganic substance is formed by CVD, a silicon component such as silane or disilane may be used as a raw material.
Furthermore, when forming an inorganic-containing layer containing silicon oxide as an inorganic material by CVD, for example, it is preferable to use tetraethoxysilane as a raw material, or to use a silicon component such as silane or disilane as a mixed gas with dinitrogen oxide (nitrous oxide).
The source gas may be diluted with hydrogen or a rare gas such as argon (Ar) or helium (He).

Furthermore, when forming an inorganic-substance-containing layer containing silicon carbide as the inorganic substance by CVD, organosilanes such as tetramethylsilane and hexamethyldisilane may be used as raw materials. Alternatively, hydrogen gas may be mixed into a mixed gas of a silicon component such as silane or disilane and a carbon component such as an alkane having 1 to 6 carbon atoms. However, other raw materials may be used as long as they are capable of forming silicon carbide.
Furthermore, for example, when _a fluororesin layer is formed by CVD _{, a} fluorine-based gas such as _CF4 , _C2F4 , _C2F6 , _C3F8 , _{C4F8 , or C5F8} may be used as a raw material.

Furthermore, when forming an inorganic-containing layer containing silicon carbide oxide as the inorganic material by CVD, for example, a silicon compound (hereinafter also referred to as "silicon compound raw material") can be used as a raw material. Silicon compound raw materials can be used in any state, such as gas, liquid, or solid, at room temperature and pressure. If gaseous, they can be introduced directly into the reactor (e.g., the discharge space). If liquid or solid, they can be vaporized by heating, bubbling, decompression, ultrasonic irradiation, or other means before use. They can also be used after dilution with a solvent; examples of the solvent include organic solvents such as methanol, ethanol, and n-hexane, as well as mixtures of these.

The above silicon compound raw materials include silane, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetra-t-butoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diphenyldimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, phenyltriethoxysilane, (3,3,3-trifluoropropyl)trimethoxysilane, hexamethoxysilane, methyltrieth ... Tyldisiloxane, bis(dimethylamino)dimethylsilane, bis(dimethylamino)methylvinylsilane, bis(ethylamino)dimethylsilane, N,O-bis(trimethylsilyl)acetamide, bis(trimethylsilyl)carbodiimide, diethylaminotrimethylsilane, dimethylaminodimethylsilane, hexamethyldisilazane, hexamethylcyclotrisilazane, heptamethyldisilazane, nonamethyltrisilazane, octamethylcyclotetrasilazane, tetrakis(dimethylamino) (amino)silane, tetraisocyanatosilane, tetramethyldisilazane, tris(dimethylamino)silane, triethoxyfluorosilane, allyldimethylsilane, allyltrimethylsilane, benzyltrimethylsilane, bis(trimethylsilyl)acetylene, 1,4-bistrimethylsilyl-1,3-butadiyne, di-t-butylsilane, 1,3-disilabutane, bis(trimethylsilyl)methane, cyclopentadienyltrimethylsilane, phenyldimethylsilane, phenyltrimethylsilane Examples of suitable silanes include propargyltrimethylsilane, tetramethylsilane, trimethylsilylacetylene, 1-(trimethylsilyl)-1-propyne, tris(trimethylsilyl)methane, tris(trimethylsilyl)silane, vinyltrimethylsilane, hexamethyldisilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, hexamethylcyclotetrasiloxane, and methyl silicate (for example, "Methyl Silicate 51" manufactured by Colcoat Co., Ltd.).

[PVD]
Examples of PVD include vacuum deposition, sputtering, and ion plating, among which vacuum deposition and sputtering are preferred. PVD is suitable, for example, when the inorganic substance contained in the inorganic substance-containing layer is a metal, a metal oxide such as niobium oxide or silicon oxide, or a metal nitride.
Vacuum deposition is suitable when the inorganic substance contained in the inorganic substance-containing layer is a metal such as gold, silver, copper, aluminum, or silicon; a metal oxide such as silicon oxide, titanium oxide, or aluminum oxide; or a fluoride such as calcium fluoride; and sputtering is suitable when the inorganic substance contained in the inorganic substance-containing layer is a metal such as gold, silver, copper, aluminum, or silicon; a metal oxide such as titanium oxide, aluminum oxide, niobium oxide, silicon oxide, ITO, or IZO; or a covalently bonded material such as DLC.

The pressure when forming the cover layer by PVD is preferably 1×10 ⁻⁷ Pa or more and 20 Pa or less, more preferably 1×10 −6 Pa or more and 10 Pa or less, and even more preferably 1×10 ⁻⁴ Pa or more and 5 Pa or less, from the viewpoints of the ability to form a concave- ^convex structure and the vacuum evacuation capability.

In the dry process of the surface treatment step (B), a cover layer may not be formed. The surface treatment when a cover layer is not formed is not particularly limited as long as the resin layer precursor can be buckled by the surface treatment to form unevenness including a wrinkle structure, and examples thereof include ion beam irradiation treatment, plasma treatment, and UV irradiation treatment.
The ion beam irradiation process is not particularly limited, but an anode layer source (ALS) that generates a linear ion beam can be used to irradiate ions of gases such as argon, nitrogen, and oxygen. Only one of these gases may be used, or two or more types of gases may be mixed. Among these, argon is preferred.
The plasma treatment is not particularly limited, and may be performed by a method such as vacuum or reduced pressure plasma treatment, with vacuum plasma treatment being preferred. The plasma treatment may be performed by converting a gas into plasma. Examples of the gas used include oxygen gas, hydrogen gas, nitrogen gas, and rare gases such as argon and helium. Only one of these gases may be used, or two or more types of gases may be mixed. Among these, argon is preferred.
The UV irradiation treatment is not particularly limited, but may be performed using a UV-LED irradiation device or the like, particularly when the curable resin composition is an active energy ray-curable resin composition. The wavelength of the UV light that can be used may be 365 nm, 385 nm, 395 nm, 405 nm, or the like, but 365 nm is preferably used.

6. Winding process (C)
In the winding step (C), the laminate obtained after the surface treatment is wound around a core and wound into a roll to obtain a second wound body. The core of the second wound body can be the same as the core described in 3. Winding step (X) above.
The length of the film wound into a roll is not particularly limited, but is preferably 5 m or more, more preferably 10 m or more, and even more preferably 50 m or more. The length of the film is preferably 10,000 m or less.
The winding tension in the winding step (C) may be selected depending on the stiffness, width and thickness of the laminate, but is preferably 10 to 500 N from the viewpoint of preventing the wound body from slipping.

<Manufacturing apparatus according to the first embodiment>
An example of the laminate manufacturing apparatus according to the first embodiment will be described below with reference to FIGS. 1 and 2. FIG.
The laminate manufacturing apparatus according to the first embodiment comprises a first apparatus 100a and a second apparatus 100b.

The first apparatus 100a shown in FIG. 1 performs the resin layer precursor forming step (A) and winding step (X) of the first embodiment, and obtains a first wound body consisting of a substrate α with a resin layer precursor. The first apparatus 100a has at least an application means 101 that applies a curable resin composition to the substrate 11, and a first winding means 102 that winds the substrate with the resin layer precursor into a roll. The first apparatus 100a may also have a drying means 103 that dries the resin layer precursor. Furthermore, if the substrate 11 is in roll form, it may also have a first unwinding means 104.

The coating means 101 is not particularly limited as long as it can adopt the above-mentioned coating method, and a known coating device may be used. The coating means 101 applies the curable resin composition onto the substrate 11, thereby obtaining a substrate α with a resin layer precursor.
A known device capable of winding a film into a wound body may be used as the first winding means 102. The first winding means 102 winds the substrate α with the resin layer precursor around the core.
As the drying means 103, a known drying device such as an oven or a reduced pressure dryer can be used.
As the first unwinding means 104, a known unwinding device capable of unwinding a roll of film may be used.

The second device 100b shown in Figure 2 performs the unwinding process (Y), surface treatment process (B), and winding process (C) in the first embodiment. A roll coater such as the W35 series manufactured by Kobe Steel, Ltd. may be used as the second device 100b.

The second device 100b is an example of a device that performs surface treatment by sputtering.
The second device 100b has at least a second unwinding means 105 that unwinds the substrate α with the resin layer precursor from the first wound body, surface treatment means 106a and/or 106b, and a second winding means 107 that winds the obtained laminate 10 into a roll.
The second device 100b is a roll-to-roll type film transport device, and it is preferable that the second unwinding means 105, the surface treatment means 106a and/or 106b, and the second winding means 107 are arranged in this order along the transport direction.
In the second device 100b, the substrate α with the resin layer precursor unwound by the second unwinding means 105 is guided and transported by the film-forming roller 108 and guide rollers 109a to 109e, and is surface-treated by the surface treatment means 106a and/or 106b, and is then wound up as a second wound body by the second winding means 108.
2 is an example and is not particularly limited to the number of film-forming rollers and guide rollers. Furthermore, the film may be transported by a transport means other than the guide rollers.

As the second unwinding means 105, a known unwinding device capable of unwinding a roll of film may be used.
Only one of the surface treatment means 106a and 106b may be used. When a plurality of surface treatment means are provided as shown in Fig. 2, the surface treatment means 106a at the front stage may be configured with an ion beam irradiation mechanism or the like that does not involve film formation, and the surface treatment means 106b at the rear stage may be configured with a sputtering device or the like that is capable of film formation. Furthermore, when performing surface treatment by heating the substrate α with the resin layer precursor, it is preferable to use a film formation roller 108 that can be controlled in temperature.
A known device capable of winding a film into a wound body may be used as the second winding means 107. The second winding means 107 winds the laminate 10 around the core.

<Manufacturing method according to the second embodiment>
A manufacturing method according to a second embodiment of the present invention (hereinafter also referred to as the "second manufacturing method") involves continuously carrying out the resin layer precursor forming step (A), the surface treatment step (B), and the winding step (C) while transporting the substrate. According to the second manufacturing method, the manufacturing steps can be further shortened, resulting in better productivity.
In addition, "continuously" means that the production is carried out without unwinding or winding in between, and does not prevent processes other than unwinding and winding from being inserted between the resin layer precursor formation process (A), the surface treatment process (B), and the winding process (C).
The second manufacturing method is suitable for use in the case where CVD or the like that does not require a high degree of vacuum is used in the surface treatment step (B). To continuously transport the substrate from atmospheric pressure to a reduced pressure environment, for example, an ATV (Air to Vacuum) device (manufactured by Hitachi Zosen Corporation) or the like can be used.

The resin layer precursor forming step (A), semi-curing step (P), surface treatment step (B), and winding step (C) in the second manufacturing method are the same as the resin layer precursor forming step (A), semi-curing step (P), surface treatment step (B), and winding step (C) described in the first manufacturing method.
However, in the second manufacturing method, the substrate with the resin layer precursor obtained in the resin layer precursor forming step (A) is not wound up, but is transported as it is to the surface treatment step (B).

From the viewpoint of facilitating the continuous performance of the resin layer precursor formation process (A) and the surface treatment process (B), the length of the substrate is preferably 5 m or more and 5,000 m or less, more preferably 10 m or more and 1,000 m or less, and even more preferably 50 m or more.

In the second manufacturing method, the conveying speed in the resin layer precursor forming step (A), surface treatment step (B), and winding step (C) is preferably 0.1 m/min or more and 30 m/min or less, more preferably 0.2 m/min or more and 20 m/min or less, and even more preferably 10 m/min or less. By keeping the conveying speed within the above range, surface treatment can be carried out sufficiently while improving productivity, making it easier to form unevenness including a wrinkled structure.

The semi-curing step (P) is not essential in the second manufacturing method either, but if you want to control the uneven structure, it is preferable to perform the semi-curing step (P) between the resin layer precursor formation step (A) and the surface treatment step (B).

<<Laminate>>
A laminate 10 obtained by the manufacturing method of the present invention has, for example, a substrate 11 and a resin layer 12 provided on at least one surface 11A of the substrate 11, as shown in FIGS.

In the laminate 10, no other layer may be provided on the resin layer 12, and the resin layer 12 may be the outermost surface 10A of the laminate 10 on one surface 11A of the substrate 11, as shown in Fig. 3. In addition, the laminate 10 preferably has a cover layer 13 provided on the resin layer 12, as shown in Fig. 4.
In the laminate 10, the resin layer 12 may be formed on the substrate 11 so as to be in direct contact with it, or an adhesive layer or other layer may be appropriately provided between the resin layer 12 and the substrate 11.
The laminate obtained by the production method of the present invention will be described in more detail below.

<Unevenness on the top surface>
The laminate 10 has an outermost surface 10A of the laminate 10 on one surface 11A side of the substrate 11, which has projections and recesses.
The laminate 10 has irregularities on the outermost surface, and is therefore applicable to various uses that utilize the fine irregularities on the surface (such as adhesion prevention and light transparency).
For example, if a liquid-repellent material is selected for the layer that forms the outermost surface 10A of the laminate 10, the contents will not easily adhere to the surface of the laminate, making it applicable to packaging materials.
Furthermore, if the adhesion of cells, bacteria, etc. can be reduced by controlling the uneven structure, it could also be used in sanitary materials.
Furthermore, by providing the outermost surface with irregularities, good fogging properties can be achieved, and for example, the haze and light transmittance of the laminate can be controlled.

The unevenness on the outermost surface preferably has a wrinkle structure.
Here, the wrinkled structure refers to a wrinkled shape that occurs due to the buckling of the resin layer 12, and is different from the uneven shape that has many dot-like protrusions, such as the uneven shape formed by particles. In this embodiment, the unevenness is formed by the buckling of the resin layer itself, so that an uneven surface can be formed that is free from the risk of particle shedding. Furthermore, because this wrinkled structure is formed spontaneously, a mold such as a transfer sheet is not required.

Figure 5 shows a schematic diagram of a wrinkle structure. The wrinkle structure is composed of multiple undulations (c), each of which has a protrusion (a) and a groove (b). The protrusions (a) and grooves (b) each have a straight line, a curve, or a combination of these. The protrusions (a) are formed irregularly. The protrusions (a) may be formed continuously or discontinuously.

The wrinkle structure is formed when compressive stress is applied along the surface direction to the resin layer 12. It is presumed that the compressive stress is applied in multiple directions along the surface direction, which causes the protrusions a and grooves b to be formed irregularly.
The presence or absence of a wrinkle structure can be confirmed by observing the outermost surface of the laminate with a microscope such as a scanning electron microscope (SEM) at a magnification of, for example, about 1,000 to 100,000 times (see Figures 7 to 17). When a wrinkle structure is present, the protrusions a and grooves b appear to form undulations c. The undulations c can be observed in a square or rectangular observation image with a side of, for example, about 0.5 to 500 μm, preferably about 1 to 100 μm.
The protrusions a that form the wrinkle structure are irregular, and the undulations c appear at a period on the order of micrometers. Therefore, as shown in Figures 7 to 17, the undulations c formed by the protrusions a and grooves b appear as multiple peaks of the protrusions a and multiple bottoms of the grooves b, even when viewed in multiple directions (e.g., three directions) such as the vertical, horizontal, and diagonal directions in the observation image. The period of the undulations c is typically not constant, and therefore the distance between the peaks of the protrusions a and the distance between the bottoms of the grooves b are also not constant.
The "period of the undulations c" refers to the distance d between the apex of a protrusion a and the apex of a protrusion a adjacent to a groove b adjacent to the protrusion a, as shown in FIG.

The wrinkle structure may also have two or more wrinkle structures with different undulation periods (hereinafter also referred to as a "high-order wrinkle structure").
For example, the wrinkle structure may include a primary wrinkle structure and a secondary wrinkle structure having a smaller undulation period than the primary wrinkle structure.
Fig. 6 is a schematic diagram showing a case where a primary wrinkle structure and a secondary wrinkle structure are included. In Fig. 6, the primary wrinkle structure is composed of a plurality of undulations c, and the secondary wrinkle structure is composed of a plurality of undulations c' with a smaller period than the undulations c in each of the protrusions a and grooves b that make up the plurality of undulations c.
In other words, the wrinkle structure preferably has a primary wrinkle structure and a secondary wrinkle structure formed by finer ridges a' and grooves b' in the relatively large ridges a and grooves b that form the primary wrinkle structure. In this way, by having a secondary wrinkle structure in addition to the primary wrinkle structure, it is possible to form a pseudo-fractal surface.
Whether or not a primary and secondary wrinkle structure is present can be determined by whether undulations appear in both of two observation images taken at different magnifications. For example, even if the ratio (Y/X) of the magnification (X) of one observation image to the magnification (Y) of the other observation image is 5 or greater (Y>X), it can be determined that a primary and secondary wrinkle structure is present if the undulations are observed in both observation images.

The fact that the unevenness of the outermost surface 10A of the laminate 10 has a wrinkle structure formed spontaneously is reflected in, for example, the value of Ssk (skewness).
Ssk is a parameter indicating the degree of unevenness of the surface. This unevenness Ssk represents the cube mean of Z(x, y) on a reference plane that has been made dimensionless by the cube of the root-mean-square height Sq. It means skewness and is a numerical value that indicates the symmetry of the peaks and valleys around the average plane. Therefore, when the unevenness Ssk<0, it means that there is a downward bias with respect to the average line, that is, there are more concave valleys than convex peaks. On the other hand, when Ssk>0, it means that there is an upward bias with respect to the average line, that is, there are more convex peaks than concave valleys. And when the unevenness Ssk=0, it means that there is symmetry (normal distribution) with respect to the average line.

The wrinkle structure of the outermost surface 10A of the laminate 10 of the present invention is a wrinkled shape caused by buckling of the resin layer 12. Therefore, compared to the uneven shape formed by particles, the wrinkle structure has a higher symmetry between the convex peaks and the concave valleys. Therefore, it is considered that the Ssk of the wrinkle structure of the laminate 10 of the present invention is closer to 0 than the Ssk of the uneven shape formed by particles.
From this viewpoint, the absolute value of Ssk of the outermost surface 10A of the laminate 10 is preferably 20 or less, more preferably 15 or less, and even more preferably 10 or less. Among these, 8 or less is preferable, 6 or less is more preferable, and 4 or less is even more preferable. Furthermore, among these, 2 or less is preferable, 1 or less is more preferable, and 0.8 or less is even more preferable. Furthermore, 0.5 or less is preferable, 0.3 or less is more preferable, and 0.1 or less is even more preferable.

It should be noted that Ssk is a parameter based on ISO25178 and can be calculated, for example, by the following method.
Using a three-dimensional non-contact surface shape measuring device (VertScan 2.0 R5200G manufactured by Ryoka Systems Co., Ltd.), measurements were performed using a SONY HR-50 1/3 inch CCD camera (10x objective lens, 530 nm white wavelength filter) in measurement mode; Wave, with a measurement area of 469.17 μm × 351.89 μm. The accompanying analysis software (VS-Viewer Version 5.1.3) was used to remove waviness components from the captured image using polynomial fourth-order approximation surface correction, and then interpolation processing (a process in which height data is compensated for by height data calculated from surrounding pixels for pixels from which height data could not be obtained) can be performed to calculate the height.

The outermost surface 10A of the laminate preferably has a specific surface area (S/A) of 1.001 or more. A specific surface area of 1.001 or more means that the wrinkle structure provides a sufficiently large surface area. Therefore, in optical applications, haze tends to occur, and adjusting the specific surface area allows the haze value of the laminate to be adjusted.
From the above viewpoint, the specific surface area (S/A) is more preferably 1.005 or more, even more preferably 1.01 or more, still more preferably 1.05 or more, and even more preferably 1.1 or more.
The specific surface area (S/A) is not particularly limited, but is preferably 2 or less, more preferably 1.7 or less, and even more preferably 1.5 or less, in order to prevent the protrusions of the wrinkle structure from becoming too high and reducing the structural strength.
The specific surface area (S/A) can be calculated by S/A, where A is the area of the measurement target area on the outermost surface 10A and S is the surface area of the measurement target area. More specifically, it can be determined by the method shown in the examples described later.

The Sa (arithmetic mean roughness) of the outermost surface 10A of the laminate is not particularly limited, but is, for example, 20 nm or more. Setting Sa to 20 nm or more means that sufficient unevenness is formed by the wrinkle structure, and when applied to optical materials, for example, haze can be adjusted. From these perspectives, Sa (arithmetic mean roughness) is preferably 30 nm or more, more preferably 50 nm or more, and even more preferably 100 nm or more.
Furthermore, Sa (arithmetic mean roughness) is not particularly limited, but from the viewpoint of maintaining the physical strength of the wrinkle structure, it is preferably 3000 nm or less, more preferably 2000 nm or less, even more preferably 1500 nm or less, still more preferably 1000 nm or less, and of these, preferably 500 nm or less.

The Sz (maximum height) of the outermost surface 10A of the laminate is not particularly limited, but is preferably 1000 nm or more, more preferably 1500 nm or more, and even more preferably 2000 nm or more. If Sz is equal to or greater than these lower limits, sufficient buckling has progressed, and a wrinkled structure with high protrusions has been formed. Therefore, when applied to optical materials, for example, the haze can be adjusted.
The Sz (maximum height) is not particularly limited, but from the viewpoint of maintaining the physical strength of the wrinkle structure, it is preferably 20,000 nm or less, more preferably 15,000 nm or less, and even more preferably 10,000 nm or less.
Sa and Sz can be measured by the method shown in the examples below.

<Applications of the laminate>
The laminate of the present invention can be suitably used for packaging food, daily necessities, industrial products, pharmaceuticals, etc. Specifically, it can be used as a packaging material such as a film. In packaging materials, by imparting water repellency and oil repellency, it can be suitably used as a component for preventing adhesion of contents and dirt.
The laminate can also be used as an optical material, where the haze and light transmittance of the optical material can be controlled by imparting cloudiness with the unevenness of the wrinkle structure, making the laminate suitable for use as a light-shielding film for windowpanes.

The laminate of the present invention may have a coating layer on the resin layer or cover layer that forms the outermost surface of the laminate, depending on the application, to the extent that the effects of the present invention are not impaired. For example, in anti-adhesion applications, the surface of the laminate can be made anti-adhesion by providing a coating layer with liquid-repellent properties.

<Explanation of terms>
In the present invention, the term "film" includes the term "sheet", and the term "sheet" includes the term "film".

The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples.
The measurement and evaluation methods used in the present invention are as follows.

(1) Method for measuring the thickness of the resin layer The surface of the resin layer was stained with _RuO4 and embedded in epoxy resin. Then, a section prepared by ultrathin sectioning was stained again with _RuO4 , and the cross section of the resin layer was measured using a TEM (Hitachi High-Technologies Corporation "H-7650", accelerating voltage 100 kV).
The thickness was determined as the average value of the maximum and minimum thicknesses.

(2) Method for Measuring the Thickness of the Cover Layer A sample was prepared by epoxy resin embedding ultrathin sectioning, and measured using a cross-sectional TEM (JEM-1200EXII, manufactured by JEOL Ltd.) at an acceleration voltage of 120 kV.

(3) Sa (arithmetic mean roughness), Sz (maximum height), and specific surface area (S/A)
The Sa, Sz, and specific surface area (S/A) of the outermost surface of the laminate were measured using a three-dimensional non-contact surface profiler (VertScan 2.0 R5200G, manufactured by Ryoka Systems Co., Ltd.) in an area of 496.17 μm × 351.89 μm using a 10x objective lens.
In the specific surface area (S/A), A represents the area of the measurement target area, S represents the surface area of the measurement target area, and S/A represents the specific surface area of the measurement target area.

(4) Measurement of Degree of Bias Based on ISO 25178, the degree of bias Ssk of the outermost surface of the laminate obtained by the method described in the specification was measured.

(5) Surface Observation The outermost surface of the laminate on one side of the substrate was photographed at 10,000 magnification and 50,000 magnification using a scanning microscope to obtain an observation image of 12.7 μm×9.5 μm and an observation image of 2.5 μm×1.9 μm.
If the wrinkle structure was visible in both the 12.7 μm × 9.5 μm observation image and the 2.5 μm × 1.9 μm observation image, the sample was evaluated as A (primary and secondary wrinkles present), if the wrinkle structure was visible in either of the observation images, the sample was evaluated as B (primary wrinkles present), and if the wrinkle structure was not visible in either of the observation images, the sample was evaluated as C (no wrinkles).

Example 1
(Preparation of Thermosetting Resin Composition (AC1))
A solid content of 42.4 parts by mass of acrylic polyol as a binder resin (manufactured by Nippon Shokubai Co., Ltd., product name "UV-G301", 42.4% solids ethyl acetate solution), and an isocyanate compound as a curing agent (manufactured by Mitsui Chemicals, Inc., product name "Takenate D-165N", hexamethylene diisocyanate compound, solids content 100%) were added to 18.46 parts by mass of a solvent containing methyl ethyl ketone: propyl acetate: butyl acetate: propylene glycol monomethyl ether acetate = 5: 2: 2: 1 mixed in a ratio of 1:1 to give a solids concentration of 15% by mass, and a diluted solution of the thermosetting resin composition (AC1) was prepared. The R ((number of isocyanate groups in the curing agent) / (number of hydroxyl groups in the binder resin)) of the thermosetting resin composition (AC1) was 1.5.

A substrate wound body, consisting of a PET film (manufactured by Mitsubishi Chemical Corporation, product name "T100-75S," 75 μm thick, 520 mm wide, and 450 m long) wound around a core, was transported at a transport speed of 5 m/min. A diluted solution of the thermosetting resin composition (AC1) was applied to one side of the PET film using a two-roll reverse coating method. The PET film was then heated for a total of 72 seconds in a drying oven set at 80°C and another set at 100°C to form a resin layer precursor. The film was then wound around the core with a winding tension of 70 N, with the resin layer precursor facing outward, to obtain a first wound body consisting of a substrate with a resin layer precursor. This was then left at room temperature (23°C) for 22 hours, after which the sputtering process described below was initiated.

(Formation of cover layer)
Using a sputter roll coater (W35 series, manufactured by Kobe Steel, Ltd.), the first wound body was unwound and transported at a transport speed of 0.3 m/min, and sputtering was performed by a roll-to-roll method.The resulting laminate was then wound around a core with a winding tension of 60 N, with the cover layer facing outward, to obtain a second wound body having a laminate structure of substrate/resin layer/cover layer.
The temperature of the deposition roller in contact with the substrate during sputtering (MR temperature) was 40°C, silicon (polycrystalline silicon) was used as the target material, and reactive sputtering was performed using a dual magnetron sputtering method, introducing 350 sccm of argon and 40 sccm of oxygen, under conditions of a reduced pressure of 0.48 Pa and a power of 5 kW, to form an inorganic-containing layer (silicon oxide layer) with a thickness of 100 nm on the semi-cured resin layer precursor.

Example 2
The same procedure as in Example 1 was carried out except that the conveying speed in the sputter roll coater was changed to 1 m/min.

Example 3
The same procedure as in Example 2 was carried out, except that the thickness of the resin layer was changed as shown in Table 1 by adjusting the gap between the two rolls and the rotation speed ratio in the reverse coating method.

Example 4
The same procedure as in Example 1 was carried out except that the temperature of the film-forming roller (MR temperature) in the sputter roll coater was changed to 60°C.

Example 5
The same procedure as in Example 1 was carried out except that the temperature of the film-forming roller (MR temperature) in the sputter roll coater was changed to 80°C.

Example 6
The same procedure as in Example 1 was carried out except that the flow rates of the gases introduced into the sputter roll coater were changed to 150 sccm of argon and 38 sccm of oxygen, and the film formation pressure was changed to 0.24 Pa.

Example 7
The same procedure as in Example 1 was carried out except that the flow rates of the gases introduced during sputtering were changed to argon 350 sccm and oxygen 0 sccm to form a silicon layer.

Example 8
The first wound body was unwound using a sputter roll coater, transported at a transport speed of 0.3 m/min, and irradiated with argon ions using an ion beam irradiation mechanism (ALS: Anode Layer Source) under conditions of ALS voltage: 2000 V, argon flow rate: 27 sccm, and pressure during treatment: 0.05 Pa. The resulting laminate was then wound around a core, and a second wound body having a laminate structure of substrate/resin layer was obtained.

Example 9
In the sputter roll coater, after the first wound body was unwound, argon ions were irradiated using an ion beam irradiation mechanism (ALS: Anode Layer Source) under the following conditions: ALS voltage: 2000 V, argon flow rate: 27 sccm, and pressure during treatment: 0.05 Pa. The same procedure as in Example 1 was carried out.

Comparative Example 1
The substrate was a PET film (manufactured by Mitsubishi Chemical Corporation, product name "T100-75S") alone, which was used as Comparative Example 1.

7 to 17 show images of the laminates of Examples 1 to 9 observed with a scanning electron microscope.
In Examples 1 to 9, by subjecting the semi-cured resin layer precursor to surface treatment by a dry process using a roll-to-roll method, it was possible to form irregularities including a wrinkle structure on the outermost surface of the laminate.

Comparing Example 1 and Example 2, it was confirmed that the faster the conveying speed in the dry process, the finer the unevenness with a smaller arithmetic mean roughness Sa that was formed.
This is thought to be because when energy is applied in a reduced-pressure, dry environment, fine wrinkles form in the surface layer of the resin layer precursor due to cure shrinkage in a short period of time, and if the treatment time is further extended, the temperature rises to the lower layer of the resin layer precursor, increasing its fluidity and causing the unevenness on the surface of the laminate to grow significantly.

Comparing Example 1 with Examples 4 and 5, it was confirmed that the higher the temperature of the film-forming roller (MR temperature), the more fine and highly wrinkled structures were formed.
This is thought to be because, as the temperature of the deposition roller (MR temperature) increases, the resin layer precursor becomes more fluid, and large undulations (primary wrinkle structure) are generated by buckling due to the cure shrinkage of the resin layer precursor.Furthermore, buckling due to the film stress associated with the deposition of the cover layer also becomes more likely to occur, generating small undulations (secondary wrinkle structure) on the surface layer.

Comparing Example 1 and Example 6, it was confirmed that the lower the film formation pressure in the dry process, the more clearly the unevenness formed.
This is thought to be because the lower the film-forming pressure, the easier it is for energy to be transmitted to the resin layer precursor, resulting in a large curing shrinkage force.

Furthermore, Example 7 confirmed that the uneven structure can be changed by changing the film formation species used in the dry process.

In Example 8, it was confirmed that unevenness was formed even when the surface treatment was performed by a dry process that did not involve film formation.
Furthermore, when Example 1 and Example 8 are compared, it was confirmed that the uneven surface was smoothed by carrying out the ion beam irradiation treatment.
This is thought to be because ion beam irradiation is a process that does not involve film formation, so no film stress is generated and the remaining resin layer body flows and deforms while maintaining its smoothness.

Unlike the technology disclosed in Patent Document 1, this invention does not use particles to form the unevenness, so there is no concern about particles falling off, making it applicable to a wider range of applications.

100a First device 100b Second device 101 Coating means 102 First winding means 103 Drying means 104 First unwinding means 105 Second unwinding means 106a, 106b Surface treatment means 107 Second winding means 108 Film-forming roller 109a to 109e Guide rollers
α Substrate with resin layer precursor 10 Laminate 10A Outermost surface of laminate 11 Substrate 11A One surface of substrate 12 Resin layer 13 Cover layer

Claims (13)

a resin layer precursor-forming step (A) of applying a curable resin composition to at least one surface of a substrate to obtain a substrate with a resin layer precursor;
a surface treatment step (B) of performing a surface treatment on the semi-cured or uncured substrate with the resin layer precursor by a dry process to obtain a laminate having irregularities on the outermost surface;
and a winding step (C) of winding the laminate into a roll,
After the resin layer precursor forming step (A),
a winding step (X) of winding the substrate with the resin layer precursor into a roll;
an unwinding step (Y) of unwinding the substrate with the resin layer precursor from the roll;
The method for producing a laminate further comprises the step (B) of performing a surface treatment. The method for producing a laminate described in claim 1, wherein the surface treatment step (B) and the winding step (C) are performed while transporting the substrate with the resin layer precursor. a resin layer precursor-forming step (A) of applying a curable resin composition to at least one surface of a substrate to obtain a substrate with a resin layer precursor;
a surface treatment step (B) of performing a surface treatment on the semi-cured or uncured substrate with the resin layer precursor by a dry process to obtain a laminate having irregularities on the outermost surface;
and a winding step (C) of winding the laminate into a roll,
the unevenness on the outermost surface of the laminate includes a wrinkle structure,
A method for manufacturing a laminate, wherein the wrinkle structure includes a primary wrinkle structure and a secondary wrinkle structure having a smaller undulation period than the primary wrinkle structure. The method for producing a laminate according to claim 3 , wherein the resin layer precursor forming step (A), the surface treatment step (B), and the winding step (C) are carried out continuously while the substrate is being transported. After the resin layer precursor forming step (A),
A semi-curing step (P) is performed to semi-cure the resin layer precursor;
The method for producing a laminate according to any one of claims 1 to 4 , further comprising the step (B) of performing a surface treatment thereafter. 6. The method for producing a laminate according to claim 1 , wherein the surface treatment is any one of chemical vapor deposition, physical vapor deposition, and plasma treatment. The method for producing a laminate according to any one of claims 1 to 6 , wherein the temperature of the film in the surface treatment step (B) is 30°C or higher and 120°C or lower. the curable resin composition is a thermosetting resin composition,
The method for producing a laminate according to any one of claims 1 to 7 , wherein the ratio (number of isocyanate groups)/(number of hydroxyl groups) in the thermosetting resin composition is 10 or less. The method for producing a laminate according to any one of claims 1 to 8 , wherein the specific surface area (S/A) of the outermost surface of the laminate is 1.001 or more. The method for producing a laminate according to any one of claims 1 to 9 , wherein the outermost surface of the laminate has an arithmetic mean roughness Sa (arithmetic mean roughness) of 20 nm or more. The method for producing a laminate according to any one of claims 1 to 10 , wherein the outermost surface of the laminate has a maximum height Sz of 1000 nm or more. The method for producing a laminate according to any one of claims 1 to 11 , wherein the absolute value of Ssk (degree of deviation) of the outermost surface of the laminate is 20 or less. The method for producing a laminate according to any one of claims 1 to 12 , wherein a thickness (tb) of a resin layer formed by curing the applied curable resin composition is 0.1 µm or more and 15 µm or less.