JP2022051202A - Anti-fogging optical laminate and manufacturing method therefor - Google Patents

Abstract

To provide a method of manufacturing an anti-fogging laminate, which allows for manufacturing an anti-fogging laminate with superior scratch resistance.SOLUTION: A method of manufacturing an anti-fogging laminate comprises the steps of: applying a photocurable composition onto a substrate to form a coating material layer; placing a light-transmissive film on the coating material layer; and curing the coating material layer by irradiating the coating material layer with light via the light-transmissive film to obtain a cured product layer.SELECTED DRAWING: None

Description

The present disclosure relates to an anti-fog laminate and a method for producing the same.

In recent years, a base material formed of an organic material such as plastic or a base material formed of an inorganic material such as glass may be required to have anti-fog properties (anti-fog property).
For example, Patent Document 1 describes a curable composition containing a (meth) acrylic monomer as a method for producing an antifogging laminate (that is, an antifogging laminate) with respect to a base material. Disclosed is a method for producing an antifogging laminate containing a base material and a cured product layer by applying the coating to form a coating material layer and curing the formed coating material layer to convert it into a cured product layer. ing.

International Publication No. 2019/221268

However, the anti-fog laminate described in Patent Document 1 has room for improvement in terms of scratch resistance.

In view of the above circumstances, an object of one aspect of the present disclosure is to provide an anti-fog laminate having excellent scratch resistance and a method for producing the same.

The means for solving the above problems include the following aspects.
<1> A step of applying a photocurable composition on a substrate to form a coating layer, and
The step of arranging the light transmissive film on the coating material layer and
A step of irradiating the coating material layer with light through the light transmissive film to cure the coating material layer to obtain a cured product layer.
A method for producing an anti-fog laminate.
<2> The antifogging laminate according to <1>, wherein the step of arranging the light-transmitting film includes a step of removing a gas intervening between the light-transmitting film and the coating material layer. Production method.
<3> The method for producing an anti-fog laminate according to <1> or <2>, wherein the light transmissive film has an average transmittance of 40% or more in a wavelength region of 200 nm to 500 nm.
<4> Any one of <1> to <3>, wherein the photocurable composition contains a polyfunctional monomer having two or more (meth) acryloyl groups, inorganic particles, and a surfactant. The method for producing an anti-fog laminate according to the above.
<5> Base material and
The cured product layer arranged on the substrate and
Equipped with
An anti-fog laminate having a fine indentation hardness of 0.080 GPa or more measured from the cured product layer side.

According to one aspect of the present disclosure, an anti-fog laminate having excellent scratch resistance and a method for producing the same are provided.

In the present disclosure, the numerical range represented by using "-" means a range including the numerical values before and after "-" as the lower limit value and the upper limit value.
In the present disclosure, the amount of each component contained in the composition is the sum of the plurality of substances present in the composition unless otherwise specified, when a plurality of substances corresponding to each component are present in the composition. Means quantity.
In the numerical range described stepwise in the present disclosure, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of the numerical range described in another stepwise description. .. Further, in the numerical range described in the present disclosure, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.
In the present disclosure, "light" is a concept including active energy rays such as ultraviolet rays and visible light.

In the present disclosure, "(meth) acrylate" means acrylate or methacrylate, "(meth) acryloyl" means acryloyl or methacrylic acid, and "(meth) acrylic" means acrylic or methacrylic.

[Manufacturing method of anti-fog laminate]
The method for producing the anti-fog laminate of the present disclosure is as follows.
A step of applying a photocurable composition on a substrate to form a coating material layer (hereinafter, also referred to as a “coating material layer forming step”).
The step of arranging the light-transmitting film on the coating material layer (hereinafter, also referred to as "light-transmitting film arranging step"),
A step of irradiating the coating material layer with light through a light-transmitting film to cure the coating material layer to obtain a cured product layer (hereinafter, also referred to as “curing step”).
Have.
The method for producing an anti-fog laminate of the present disclosure may include other steps, if necessary.

According to the method for producing an anti-fog laminate of the present disclosure, an anti-fog laminate having excellent scratch resistance can be produced.
The reason why such an effect is exhibited is that the coating layer formed by using the photocurable composition is cured by irradiating the coating layer with light through a light-transmitting film, thereby suppressing polymerization inhibition due to oxygen. As a result, it is considered that a cured product layer having excellent hardness (that is, scratch resistance) is formed on the substrate. It is considered that the formed cured product layer also has anti-fog property, and as a result, an anti-fog layer having excellent scratch resistance is produced.

Hereinafter, each step that can be included in the method for producing the anti-fog laminate of the present disclosure will be described.

<Applicable layer forming process>
The coating material layer forming step is a step of applying a photocurable composition on a substrate to form a coating material layer.

(Base material)
There are no particular restrictions on the base material.
As a base material, for example;
Inorganic base material made of inorganic materials such as glass, silica, metal, and metal oxides;
Polymethylmethacrylate (PMMA), polycarbonate, polyallyl carbonate, polyethylene terephthalate, polyacetylcellulose (TAC), acrylonitrile-butadiene-styrene copolymer (ABS), polyethylene, polypropylene, polystyrene, polyurethane resin, epoxy resin, poly (meth) ) Organic base material made of organic materials such as acrylate resin, vinyl chloride resin, silicone resin, paper and pulp;
An organic-inorganic composite base material made of an organic-inorganic composite material (for example, SMC (Sheet Molding Compound), BMC (Bulk Molding Compound)) in which an unsaturated polyester resin and an inorganic filler (for example, glass fiber, calcium carbonate, etc.) are composited. ;
And so on.
The shape of the base material is not particularly limited, and may be a plate shape, a lens shape, or the like.
In the present disclosure, a plate-shaped base material is also referred to as a "substrate".

Examples of the base material include a base material obtained by combining a plurality of members.
As a base material in which a plurality of members are combined, for example;
Laminated board made by laminating multiple boards;
A coated substrate in which a coating (for example, an undercoat layer) is provided on the substrate;
A substrate that satisfies both of these (ie, a laminated substrate with a coating);
And so on.

Examples of the undercoat layer include a primer layer, an undercoat layer, an anchor coat layer, and the like.
The undercoat layer can be formed by using a coating agent.
As the coating agent, for example, a known coating agent containing a resin as a main component can be used.
Examples of the resin include polyester resin, polyamide resin, polyurethane resin, epoxy resin, phenol resin, (meth) acrylic resin, polyvinyl acetate resin, and the like.
Examples thereof include polyolefin resins (eg, polyethylene, polypropylene, ethylene-propylene copolymers, etc.), cellulosic resins, and the like.
The thickness of the undercoat layer is, for example, 0.5 μm to 10 μm.

The surface of the base material may be subjected to an activation treatment, if necessary.
Examples of the activation treatment include corona treatment, ozone treatment, low-temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, oxidation treatment with chemicals, flame treatment, and the like.

The method for producing an anti-fog laminate of the present disclosure may further include a substrate preparation step of preparing the above-mentioned substrate (for example, a laminated substrate with a coating) before the coating layer forming step. good.

(Photocurable composition)
As the photocurable composition, a known photocurable composition can be used.
The photocurable composition is
A polyfunctional monomer having two or more (meth) acryloyl groups (hereinafter, also referred to as “polyfunctional monomer (a1)”) and
Inorganic particles (hereinafter, also referred to as "inorganic particles (a2)"),
Surfactant (hereinafter, also referred to as "surfactant (a3)"),
Is preferably contained.
When the cured product layer is formed using the photocurable composition of the preferred embodiment, the surfactant is gradually exuded onto the surface of the cured product layer while the surfactant is stored in the cured product layer. As a result, the anti-fog property of the cured product layer is exhibited.

-Polyfunctional monomer (a1)-
The photocurable composition preferably contains at least one polyfunctional monomer (a1) (that is, a polyfunctional monomer having two or more (meth) acryloyl groups).
The polyfunctional monomer (a1) polymerizes when the photocurable composition is irradiated with light to form a network structure that forms the basic skeleton of the cured product layer. As a result, the coating layer is cured and converted into a cured layer. In the obtained cured product layer, a space in which the surfactant is stored is formed as a gap in the network structure.

The polyfunctional monomer (a1) preferably comprises two or more (meth) acryloyl groups and a linker moiety that fixes these two or more (meth) acryloyl groups in one molecule.
The polyfunctional monomer (a1) is preferably an ester of (meth) acrylic acid and a polyhydric alcohol having two or more hydroxyl groups.
Here, as "a polyhydric alcohol having two or more hydroxyl groups", for example;
Alkane polyols such as alkanediol and alkanetriol;
Compounds containing a polyoxyalkylene structure such as polyalkylene glycol (for example, polyethylene glycol, polypropylene glycol, etc.), compounds obtained by adding polyalkylene glycol to an alkane polyol;
And so on.
The "polyhydric alcohol having two or more hydroxyl groups" may contain an aromatic ring and / or an aliphatic ring. Examples of the "multihydric alcohol having two or more hydroxyl groups" containing an aromatic ring include ethylene oxide adducts of bisphenol.

As the "multihydric alcohol having two or more hydroxyl groups", a compound having a polyoxyalkylene structure is preferable, and a diol containing a polyoxyethylene structure is more preferable.

Specific examples of the polyfunctional monomer (a1) include compounds represented by the following formula (1) or the following formula (2).
The polyfunctional monomer (a1) preferably contains a compound represented by the following formula (1).

In the formula (1), n represents an integer of 1 to 30.
In the formula (2), l and m represent numbers in which l + m is an integer of 2 to 40.

Specific examples of the polyfunctional monomer (a1) include polyethylene glycol diacrylate and 2,2-bis- [4- (acryloxy-polyethoxy) phenyl] -propane.
Examples of the polyethylene glycol di (meth) acrylate include tetradecaethylene glycol di (meth) acrylate and tricosaethylene glycol di (meth) acrylate.

The polyfunctional monomer (a1) that can be contained in the photocurable composition may be one kind alone or a combination of two or more kinds.
The content of the polyfunctional monomer (a1) in the photocurable composition is preferably 30% by mass to 70% by mass, more preferably 35% by mass to 60% by mass, based on the total dry mass of the photocurable composition. Is.

In the present disclosure, the "total dry mass" of a composition means the total mass of all components other than the solvent in the composition.

The content of the polyfunctional monomer (a1) in the photocurable composition is preferably 10% by mass to 50% by mass, more preferably 15% by mass to 35% by mass, based on the total amount of the photocurable composition. ..

-Inorganic particles (a2)-
The photocurable composition preferably contains at least one kind of inorganic particles (a2).
The inorganic particles (a2) play a role of imparting appropriate hardness and strength to the cured product layer.
As the inorganic particles (a2), particles containing an inorganic substance are preferable, and particles substantially made of an inorganic substance are more preferable.
Examples of the inorganic substance include metal oxides such as silica, zirconia, alumina, tin oxide, antimony oxide, and titania, and nanodiamond and the like.
Among these, silica or zirconia is particularly preferable from the viewpoint of dispersibility in resin, hardness, light resistance and the like.

The particle size of the inorganic particles (a2) is preferably 5 nm to 50 nm, more preferably 10 nm to 30 nm.
When the particle size of the inorganic particles (a2) is 5 nm or more, it is advantageous from the viewpoint of the hardness of the cured film and the dispersibility in the cured film.
When the particle size of the inorganic particles (a2) is 50 nm or less, it is advantageous from the viewpoint of the transparency of the cured film.
Here, the particle size of the inorganic particles (a2) means a value obtained by a dynamic scattering method using a laser beam.

The inorganic particles (a2) may contain an inorganic substance or a trace amount of an organic substance that does not affect the physical properties of the inorganic particles (a2).
For example, the inorganic particles (a2) may be inorganic particles modified with a functional group containing a (meth) acryloyl group (hereinafter, also referred to as inorganic particles (a2-1)).
When the photocurable composition contains inorganic particles (a2-1), when the photocurable composition is cured, the (meth) acryloyl group in the inorganic particles (a2-1) and the polyfunctional monomer (a1) are contained. Can react with the (meth) acryloyl group of. As a result, the inorganic particles (a2-1) and the network structure formed by the polyfunctional monomer (a1) are integrated. As a result, the scratch resistance and anti-fog property of the cured film are further improved.
The inorganic particles (a2-1) are particularly preferably silica particles modified with a functional group containing a (meth) acryloyl group, or zirconia particles modified with a functional group containing a (meth) acryloyl group.

When the photocurable composition contains inorganic particles (a2-1), the ratio of the inorganic particles (a2-1) to the total mass of the inorganic particles (a2) contained in the photocurable composition is preferable. It is 30% by mass to 100% by mass, more preferably 50% by mass to 100% by mass, and further preferably 70% by mass to 100% by mass.

Inorganic particles (a2-1) are also available as commercial products.
Examples of commercially available products of silica particles modified with a functional group containing a (meth) acryloyl group include an organosilica sol PGM-AC-2140Y manufactured by Nissan Chemical Industries, Ltd.

The inorganic particles (a2) that can be contained in the photocurable composition may be one kind alone or a combination of two or more kinds.
The content of the inorganic particles (a2) in the photocurable composition is preferably 30% by mass to 70% by mass, more preferably 40% by mass to 60% by mass, based on the total dry mass of the photocurable composition. be.

The content of the inorganic particles (a2) in the photocurable composition is preferably 10% by mass to 50% by mass, more preferably 20% by mass to 40% by mass, based on the total amount of the photocurable composition.

The content mass ratio of the inorganic particles (a2) to the polyfunctional monomer (a1) in the photocurable composition (that is, the content mass ratio [inorganic particles (a2) / polyfunctional monomer (a1)]) is preferably 0. It is 6.6 to 2.0, more preferably 0.8 to 1.6, and even more preferably 1.0 to 1.4.

-Surfactant (a3)-
The photocurable composition preferably contains at least one surfactant (a3).
The surfactant (a3) plays a role of imparting anti-fog property to the cured film by gradually advancing to the surface of the cured film while being stored in the cured film.
The surfactant (a3) is not particularly limited as long as it can play such a role, but preferably has a polyoxyalkylene structure.

When the surfactant (a3) has a polyoxyalkylene structure, it is preferable that the surfactant (a3) does not have a (meth) acrylic polymer structure.
That is, it is preferable that the surfactant (a3) does not have either a structure represented by the following formula (AC1) or a structure represented by the following formula (AC2):

In the formula (AC1) and the formula (AC2), R represents a hydrogen atom or a methyl group, and n represents an integer of 2 or more.

It is also preferable that the surfactant (a3) does not contain an unsaturated bond.

More specifically, as the surfactant (a3), a surfactant containing a hydrocarbon group and a polyoxyalkylene structure is preferable.
As the hydrocarbon group, an alkyl group is preferable.
Examples of the polyoxyalkylene structure include a structure in which an oxyalkylene group is repeated. As the oxyalkylene group, -O-CH ₂ CH _2- , -O-CH ₂ CH ₂ CH _2- , or -O-CH ₂ CH ₂ CH ₂ CH _2- is preferable, and -O-CH ₂ CH _2- Is more preferable.
The number of oxyalkylene groups contained in the surfactant (a3) is preferably 1 to 30.

The surfactant (a3) preferably further contains an anionic hydrophilic group.
Examples of anionic hydrophilic groups include sulfo groups, carboxy groups, phosphate groups, O-sulfate groups (-O ^- SO _3- ), N-sulfate groups (-NH ^- SO _3- ) and the like. Among these anionic hydrophilic groups, a phosphate group and an O-sulfate group (-O ^- SO _3- ) are preferable.
These anionic hydrophilic groups may be in the form of free acids or salts.
As the salt, a sodium salt, a potassium salt, or an ammonium salt is preferable.

As an example of a suitable surfactant (a3), a compound represented by the following formula (SS1) can be mentioned.

In the formula (SS1), R represents an alkyl group having 10 to 20 carbon atoms or an alkenyl group having 10 to 20 carbon atoms, L represents an alkylene group having 2 to 4 carbon atoms, and n represents 1 to 30 carbon atoms. Representing an integer, X represents a hydroxyl group, a sulfo group, a phosphono group, a carboxy group, a phosphate group, an O-sulfate group, an N-sulfate group, a sulfo group salt, a phosphono group salt, a carboxy group salt, and a phosphate group. Represents a salt of, an O-sulfate group salt, or an N-sulfate group salt.

In the formula (SS1), examples of "-OL-" include -O-CH _{2 CH 2-, -O-CH 2 CH 2 CH 2-} , -O-CH ₂ CH ₂ CH ₂ CH _2- Etc., and among these, -O-CH ₂ CH _2- is preferable.
In the formula (SS1), as X, a phosphoric acid group, an O-sulfate group, a salt of a phosphoric acid group, or a salt of an O-sulfate group is more preferable.
As the "salt" in X, a sodium salt, a potassium salt, or an ammonium salt is preferable, and a sodium salt is more preferable.

Among the surfactants (a3), examples of the surfactant having an anionic hydrophilic group include polyoxyalkylene alkyl ether sulfate, polyoxyalkylene alkenyl ether sulfate, and mixtures thereof.
As examples of surfactants having anionic hydrophilic groups, more specifically, polyoxyethylene oleylcetyl ether sulfate such as polyoxyethylene oleylcetyl ether sulfate, and polyoxyethylene such as polyoxyethylene lauryl ether sulfate sodium sulfate. Examples include lauryl ether sulfate.

The surfactant (a3) may be a nonionic surfactant having a polyoxyalkylene structure.
Examples of the nonionic surfactant having a polyoxyalkylene structure include polyoxyalkylene alkyl ethers such as polyoxyalkylene monoalkyl ethers, polyoxyalkylene alkenyl ethers such as polyoxyalkylene monoalkenyl ethers, and mixtures thereof. Can be mentioned.
Here, examples of the polyoxyalkylene alkyl ether include polyoxyalkylene branched decyl ether, polyoxyalkylene dodecyl ether (polyoxyalkylene lauryl ether), polyoxyalkylene tridecyl ether, and polyoxyalkylene oleyl cetyl ether.
The polyoxyalkylene alkyl ether is preferably a polyoxyethylene alkyl ether (for example, polyoxyethylene isodecyl ether, polyoxyethylene lauryl ether, etc.).

As the surfactant (a3), in addition to the above-mentioned surfactant, the surfactant described in paragraphs 0062 to 0069 of International Publication No. 2019/221268 may be used.

The surfactant (a3) that can be contained in the photocurable composition may be one kind alone or a combination of two or more kinds.
The content of the surfactant (a3) in the photocurable composition is preferably 1.0% by mass to 10% by mass, more preferably 2.0, based on the total dry mass of the photocurable composition. It is from mass% to 8.0% by mass, more preferably 3.0% by mass to 7.0% by mass.

The content of the surfactant (a3) in the photocurable composition is preferably 0.5% by mass to 6.0% by mass, more preferably 1.0, based on the total amount of the photocurable composition. It is by mass% to 5.0% by mass.

-Photopolymerization initiator-
The photocurable composition preferably contains at least one photopolymerization initiator.
The photopolymerization initiator is preferably a photoradical polymerization initiator.
As the photoradical polymerization initiator, a known photoradical polymerization initiator can be used.
Examples of the photoradical polymerization initiator include alkylphenone-based compounds, acylphosphine oxide-based compounds, titanosen-based compounds, oxime ester-based compounds, benzoin-based compounds, acetophenone-based compounds, benzophenone-based compounds, thioxanthone-based compounds, and α-acidro. Examples thereof include xim ester compounds, phenylglycilate compounds, benzyl compounds, azo compounds, diphenyl sulfide compounds, organic dye compounds, iron-phthalocyanine compounds, benzoin ether compounds, anthraquinone compounds and the like. Of these, alkylphenone-based compounds and acylphosphine oxide-based compounds are preferable from the viewpoint of reactivity and the like.
A commercially available product can also be used as the photoradical polymerization initiator.
As a commercial product of the photoradical polymerization initiator, for example;
Omnirad 127, 184, 1173, 500, 819, TPO (all manufactured by IGM resin B.V.);
Esacure ONE, KIP100F, KT37, KTO46 (all manufactured by Lamberty);
And so on.

The photopolymerization initiator that can be contained in the photocurable composition may be one kind alone or a combination of two or more kinds.
The content of the photopolymerization initiator in the photocurable composition is preferably 0.4% by mass to 10% by mass, more preferably 0.6% by mass, based on the total dry mass of the photocurable composition. It is about 6.0% by mass, more preferably 1.0% by mass to 4.0% by mass.

The content of the surfactant (a3) in the photocurable composition is preferably 0.2% by mass to 6.0% by mass, more preferably 0.4% by mass, based on the total amount of the photocurable composition. It is by mass% to 4.0% by mass, more preferably 0.6% by mass to 3.0% by mass.

-solvent-
The photocurable composition preferably contains at least one solvent.
As a solvent, for example;
Methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, n-pentanol, isopentanol, n-hexanol, n-octanol, 2-ethyl-hexanol, 2-methoxyethanol, 2 -Ethoxyethanol, 2-n-propoxyethanol, 2-isopropanolethanol, 2-butoxyethanol, 1-methoxy-2-propanol (also known as propylene glycol monomethyl ether), 1-ethoxy-2-propanol, 1-n- Alcohols such as propoxy-2-propanol, 1-isopropanol-2-propanol, cyclohexanol;
Ethers such as diethyl ether, tetrahydrofuran, dioxane;
Nitriles such as acetonitrile;
Esters such as ethyl acetate, acetic acid-n-propyl, acetate-n-butyl;
Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone;
Amides such as N, N-dimethylformamide, N, N-dimethylacetamide;
water;
And so on.
Of these, alcohols, ketones, or a mixed solvent of alcohols and ketones are preferable.

The content of the solvent in the photocurable composition is preferably 20% by mass or more, more preferably 30% by mass or more, still more preferably 35% by mass or more, based on the total amount of the photocurable composition. be.
The upper limit of the content of the solvent with respect to the total amount of the photocurable composition is, for example, 80% by mass, preferably 70% by mass, and more preferably 60% by mass, although it depends on the amount of other components.

The photocurable composition may contain other components other than the above-mentioned components.
For other components, the description in paragraphs 0032 to 0163 of International Publication No. 2019/221268 can be referred to as appropriate.

(Applying method, etc.)
In the coating layer forming step, the photocurable composition is applied onto the substrate to form the coating layer.
The application of the photocurable composition can be appropriately performed by a conventionally known method.
Examples of the coating method include a bar coating method, a spin coating method, a dip coating method, a spray coating method, a sink coating method, a brush coating method, a gravure coating method, a reverse roll coating method, a knife coating method, and a kiss coating method.
In the coating layer forming step, the photocurable composition may be applied onto the substrate, and the applied photocurable composition may be dried (for example, heat-dried) to form the coating layer.

<Light transmissive film placement process>
The light-transmitting film arranging step is a step of arranging the light-transmitting film on the coating material layer.
In the curing step described later, the coating layer is irradiated with light through a light-transmitting film. The irradiated light cures the coating layer to obtain a cured layer.
In the method for producing an antifogging laminate of the present disclosure, the coating layer is irradiated with light through a light-transmitting film, so that the coating layer is directly irradiated with light without passing through a light-transmitting film. In comparison with the case of the above, the inhibition of radical polymerization by oxygen is suppressed, and as a result, a cured product layer having excellent hardness can be obtained.

The light-transmitting film is not particularly limited as long as it is a film having light-transmitting property.
Here, having light transmittance means a property that the average transmittance in the wavelength region of 200 nm to 500 nm is 10% or more.
The average transmittance of the light-transmitting film in the wavelength region of 200 nm to 500 nm is preferably 40% or more.

The thickness of the light-transmitting film is preferably 1 μm to 100 μm, more preferably 5 μm to 80 μm, and further preferably 10 μm to 60 μm.

The light-transmitting film is not particularly limited, and is, for example, a polyethylene terephthalate (PET) film, a polyethylene naphthalate (PEN) film, a polyethylene (PE) film, a polypropylene (PP) film, or a polycarbonate (PC) film. , Polystyrene (PS) film, Polyvinyl chloride (PVC) film, Polyvinylidene chloride (PVDC) film, Polyvinyl alcohol (PVA) film, Nylon film, Polyacrylonitrile film, Ethylene-methacrylic acid copolymer film, Ethylene-vinyl alcohol Examples thereof include a copolymer film, a polyethylene acetate vinyl copolymer film, and cellophane.
As the light transmissive film, a PET film is particularly preferable.

The light-transmitting film arranging step may include a step of removing the gas interposed between the light-transmitting film and the coating material layer. As a result, the inhibition of radical polymerization by oxygen is further suppressed, and as a result, a cured product layer having a higher hardness can be obtained.
A known method can be applied as a method for removing the gas intervening between the light-transmitting film and the coating layer.
As the above method, for example, in a state where the light-transmitting film is arranged on the coating material layer, the light-transmitting film is applied to at least one side of the base material and the light-transmitting film while applying pressure with a roller or the like. A method of removing the gas intervening between the material layer and the material layer can be applied.

<Curing process>
The curing step is a step of irradiating the coating material layer with light through a light-transmitting film to cure the coating material layer and obtain a cured product layer.
The wavelength range of the irradiated light is, for example, the range of 0.0001 nm to 800 nm.
More specific examples of the light to be irradiated include α-rays, β-rays, γ-rays, X-rays, electron beams, ultraviolet rays, visible light and the like, but ultraviolet rays are preferable.
The peak wavelength of ultraviolet rays is preferably 200 nm to 450 nm, more preferably 230 nm to 445 nm, still more preferably 240 nm to 430 nm, still more preferably 250 nm to 400 nm.

The irradiation energy of light is preferably 10 mJ / cm ² to 1000 mJ / cm ² , and more preferably 50 mJ / cm ² to 500 mJ / cm ² .

<Peeling process>
The method for producing an antifogging laminate of the present disclosure may further include a peeling step of peeling the light-transmitting film from the cured product layer after the curing step.
The peeling step exposes the surface of the cured product layer. Anti-fog and scratch-resistant curing is exhibited on the surface of the exposed cured product layer.

The method for producing an anti-fog laminate of the present disclosure does not have to have a peeling step.
Even in this case, the anti-fog laminate with the light-transmitting film can be produced by the method for producing the anti-fog laminate of the present disclosure. The anti-fog laminate with a light-transmitting film can be used by peeling the light-transmitting film from the cured product layer immediately before use, if necessary.

[Anti-fog laminate]
The anti-fog laminate of the present disclosure is
With the base material
The cured product layer placed on the substrate and
Equipped with
It is an anti-fog laminate having a fine indentation hardness of 0.080 GPa or more measured from the cured product layer side.
The anti-fog laminate of the present disclosure may be provided with other elements, if necessary.

The anti-fog laminate of the present disclosure is preferably produced by the above-mentioned method for producing the anti-fog laminate of the present disclosure.
The cured product layer is preferably a layer formed by irradiating a coated material layer of a photocurable composition with light.

<Small indentation hardness>
The anti-fog laminate of the present disclosure has a fine indentation hardness of 0.080 GPa or more measured from the cured product layer side.
Therefore, the anti-fog laminate of the present disclosure is excellent in scratch resistance. Further, the anti-fog laminate of the present disclosure is also excellent in anti-fog property (particularly, anti-fog property against steam).

As described above, according to the method for producing an antifogging laminate of the present disclosure, which includes a light-transmitting film arranging step and a curing step, a cured product layer having excellent hardness can be formed, so that the above-mentioned micro-indentation hardness can be prevented. It is easier to manufacture a cloudy laminate.
In addition to the above manufacturing method, for example;
Increase the amount of inorganic particles;
Improve the crosslinkability of the cured product (eg, use a polyfunctional monomer with a large number of (meth) acryloyl groups, reduce the molecular weight per (meth) acryloyl group, etc.);
By such a method, the numerical value (GPa) of the minute indentation hardness can be adjusted to be high.
It is presumed that the reason why the fine indentation hardness is 0.080 GPa or more, that the scratch resistance is excellent and the anti-fog property (particularly, the anti-fog property against steam) is also excellent is as follows.
When the fine indentation hardness is 0.080 GPa or more, the cured product layer has a dense structure, and when an impact is received from the outside, the structure can be easily maintained and the scratch resistance is improved. Further, it is considered that the dense structure improves the sustained release property of the hydrophilic groups (for example, those derived from the surfactant) in the structure, and particularly improves the anti-fog persistence against the above.

The fine indentation hardness is preferably 0.080 GPa to 0.50 GPa, and more preferably 0.080 GPa to 0.15 GPa.
When the micro-pushing hardness of the anti-fog laminate of the present disclosure is 0.50 GPa or less, the resistance to cracking and the initial anti-fog characteristics are further improved.

In the present disclosure, the microindentation hardness is determined in accordance with ISO14577. Specifically, the measurement is performed as follows.
Using a Berkovich indenter as the measuring indenter, maximum load (Pmax): 10 mN, maximum indentation depth: 1000 nm, load speed 800 to 12000 μN / sec, load time: 1 second (load holding time after reaching the maximum load), and , Creep time: Under the condition of 0.5 seconds, a load is applied from the cured product layer side of the antifogging laminate to obtain a load displacement curve.
From the obtained load-displacement curve, the contact rigidity (S) and the maximum variation (hmax) are calculated. Further, the contact depth (hc) is calculated from the following formula (1), the contact projected area (Ac) is calculated from the following formula (2), and the minute indentation hardness (H) is calculated from the following formula (3). Is calculated.
As the measuring device for the microindentation hardness, for example, HYSITRON TI PREMIER manufactured by Bruker can be used.

S: Contact rigidity P _max : Maximum load h _max : Maximum variation h _c : Contact depth ε: Constant related to indenter shape (Berkovich indenter is 0.75)
_Ac : Contact projected area H: Micro indentation hardness

<Base material>
The anti-fog laminate of the present disclosure comprises a substrate.
For specific examples and preferred embodiments of the base material, the section "Method for producing an anti-fog laminate" can be appropriately referred to.

<Cured material layer>
The cured product layer preferably contains a resin, inorganic particles, and a surfactant from the viewpoint of anti-fog property.
Preferred embodiments of the inorganic particles and the surfactant that can be contained in the cured product layer are described in the section of "Method for producing an anti-fog laminate" (description of the inorganic particles (a2) and the surfactant (a3)) as appropriate. You can refer to it.
The preferable range of the content of the inorganic particles with respect to the total amount of the cured product layer is the same as the preferable range of the content of the inorganic particles (a2) with respect to the total dry mass of the photocurable composition.
The preferable range of the content of the surfactant with respect to the total amount of the cured product layer is the same as the preferable range of the content of the surfactant (a3) with respect to the total dry mass of the photocurable composition.

The resin that can be contained in the cured product layer is preferably a (meth) acrylic resin having a network structure, and more preferably a polyfunctional monomer having two or more (meth) acryloyl groups.
For a preferred embodiment of the polyfunctional monomer having two or more (meth) acryloyl groups, the section "Method for producing an anti-fog laminate" (described about the polyfunctional monomer (a1)) can be appropriately referred to.
The preferable range of the resin content with respect to the total amount of the cured product layer is the same as the preferable range of the content of the polyfunctional monomer (a1) with respect to the total dry mass of the photocurable composition.

(Thickness of hardened material layer)
The thickness of the cured product layer is preferably 4 μm or more, more preferably 6 μm or more, and further preferably 10 μm or more.
When the thickness of the cured product layer is 4 μm or more, the anti-fog property and the anti-fog durability of the anti-fog layer are excellent. In this case, for example, excellent anti-fog property is exhibited even after washing the anti-fog laminate with water.
There is no particular limitation on the upper limit of the thickness of the cured product layer.
From the viewpoint of ease of manufacture (for example, coatability) and appearance of the cured product layer, the cured product layer is preferably 40 μm or less, more preferably 30 μm or less, and further preferably 25 μm or less.

(Water contact angle)
The contact angle (after 1 second) of water on the surface of the cured product layer is preferably 30 ° or less, more preferably 25 ° or less, and even more preferably 23 ° or less.
The lower limit of the contact angle of water (after 1 second) on the surface of the cured product layer is not particularly limited, and examples of the lower limit include 5.0 °, 10.0 °, 15.0 ° and the like.
Here, the contact angle of water (after 1 second) means the contact angle 1 second after the water droplet of pure water having a volume of 1.0 μL is deposited on the surface of the cured product layer.

The contact angle of water (after 22 seconds) on the surface of the cured product layer is preferably 14.0 ° or less, and more preferably 13.5 ° or less.
The lower limit of the contact angle of water (after 22 seconds) on the surface of the cured product layer is not particularly limited, and examples of the lower limit include 5.0 ° and 10.0 °.
Here, the contact angle of water (after 22 seconds) means the contact angle 22 seconds after the water droplet of pure water having a volume of 1.0 μL is deposited on the surface of the cured product layer.

<Other factors>
The anti-fog laminate of the present disclosure may include a light-transmitting film on the cured product layer.
The anti-fog laminate in the embodiment provided with the light-transmitting film is used, for example, by peeling (removing) the light-transmitting film from the cured product layer immediately before obtaining the anti-fog effect of the cured product layer. Will be done.

Further, the anti-fog laminate of the present disclosure may be provided with an adhesive layer on the side opposite to the side on which the cured product layer is arranged when viewed from the base material.
The anti-fog laminate having an adhesive layer is not particularly limited as an object that is attached to various objects and is used to impart anti-fog properties to the objects. for example;
Exterior walls in vehicles or buildings;
Windowpanes in vehicles or buildings;
Mirrors in bathrooms;
Surfaces of display elements for personal computer displays, mobile phone displays, televisions, etc.;
Information boards such as signboards, advertisements, information boards;
Railroad, road signs;
And so on.

The adhesive layer contains an adhesive.
The pressure-sensitive adhesive is not particularly limited, and known pressure-sensitive adhesives can be used.
Examples of the pressure-sensitive adhesive include an acrylic pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, a vinyl ether polymer-based pressure-sensitive adhesive, and a silicone pressure-sensitive adhesive.
The thickness of the adhesive layer is preferably 2 μm to 50 μm, more preferably 5 to 30 μm.

<Use>
The anti-fog laminate of the present disclosure can be suitably used as an anti-fog material, an anti-fouling material, a quick-drying material, a dew condensation prevention material, an anti-static material and the like.
The anti-fog laminate of the present disclosure is, for example;
Optical articles such as optical films, optical disks, optical lenses, eyeglass lenses, eyeglasses, sunglasses, goggles, helmet shields, head lamps, tail lamps, windowpanes (eg, windowpanes of vehicles and buildings), etc.;
Materials for these optics;
It can be applied to various uses such as.
Further, the anti-fog laminate of the present disclosure can be applied to, for example, an image recognition system using an in-vehicle camera, which has been widely mounted on vehicles in recent years.

Hereinafter, examples of the present disclosure will be shown, but the present disclosure is not limited to the following examples.

[Example 1]
<Preparation of photocurable composition>
Under normal temperature and pressure environment, the surfactant (a3) shown in Table 1 and the inorganic particles (a2) shown in Table 1 are placed in a glass screw tube bottle in an amount having the mass content shown in Table 1. Each was added. Further, the solvent shown in Table 1 was added, and the mixture was stirred using a magnetic stirrer and a stirrer until the surfactant was completely dissolved.
Next, the polyfunctional monomer (a1) shown in Table 1 was added to the stirred glass screw tube bottle in an amount having the content mass shown in Table 1, and the mixture was thoroughly stirred until they were compatible. Then, the photopolymerization initiator shown in Table 1 is added to the stirred glass screw tube bottle in an amount having the content mass shown in Table 1, and the mixture is stirred until it is completely dissolved, and the liquid composition is used. A photocurable composition was obtained.

<Preparation of anti-fog laminate>
(Preparation of base material)
A laminated substrate was prepared by pasting a PET film (“Lumirror U483” manufactured by Toray Industries, Inc.) on a polycarbonate substrate.
A primer composition (Takelac (registered trademark) WS-5100) is applied to the surface of the above laminated substrate on the PET film side with a bar coater to form a primer layer, and the laminated substrate with a primer layer (layer structure is "primer". Layer / PET film / Polycarbonate substrate ") was obtained.

(Applicable layer forming process)
The photocurable composition was applied to a primer layer in a laminated substrate with a primer layer as a base material by a bar coater to form a coating layer (coating layer forming step).

(Light transmissive film placement process)
A light-transmitting film (polyethylene terephthalate, T-15 (trade name), thickness 37 μm, average transmittance of 200 nm to 500 nm, 53.5%, manufactured by Mitsui Chemicals Tocello Co., Ltd.) was placed on the coating layer and compacted. A roller was used to remove the gas intervening between the light-transmitting film and the coating layer.

(Curing process)
Next, the coating material layer was cured by irradiating the coating material layer with ultraviolet rays (UVA) under the condition of 210 mJ / cm ^-2 via a light transmissive film, and converted into a cured material layer.
Then, the light transmissive film (T-15) was peeled off from the cured product layer.
As described above, the anti-fog laminate comprising a substrate (that is, a substrate having a laminated structure represented by "primer layer / PET film / polycarbonate") and a cured product layer arranged on the substrate is provided. Obtained.
The laminated structure of the anti-fog laminated body is a laminated structure represented by "cured product layer / primer layer / PET film / polycarbonate substrate".

<Evaluation>
The following evaluations were carried out on the anti-fog laminate.
The results are shown in Table 1.

(Thickness of hardened material layer)
Using a film thickness measuring device (ETA-ARC, manufactured by OPTOTECH), the spectral reflectance is measured near the center of the cured product layer in the antifogging laminate, and the obtained spectral reflectance is cured by the Fourier transform method. The film thickness of the material layer was calculated.

(Scratch resistance of anti-fog laminate)
Using steel wool # 0000, an antifogging laminate is placed on top of this steel wool in an arrangement where the cured material layer is in contact with the steel wool, and 300 g or 1 kg is placed directly above the antifogging laminate. A weight was placed and a load was applied. In this state, the anti-fog laminate was reciprocated 10 times on steel wool. This reciprocating motion is No. 428 Gakushin type wear tester (friction tester type II) (manufactured by Yasuda Seiki Seisakusho Co., Ltd.) was used.
With respect to the anti-fog laminated body after the reciprocating motion, the presence or absence of scratches, the state of scratches (depth of scratches, number, etc.), and the remaining condition of the cured product layer are visually confirmed, and the anti-fog is prevented based on the following evaluation criteria. The scratch resistance of the cloudy laminate was evaluated.
In the following evaluation criteria, the rank with the best scratch resistance is rank 5.
Further, in Table 1 described later, a rank represented by a decimal number such as "2.5" represents an evaluation between rank 2 and rank 3.

-Evaluation criteria for scratch resistance of anti-fog laminate-
5: There are almost no visible scratches on the surface of the cured product layer, and the cured product layer remains entirely.
4: A state in which several to ten thin scratches are contained on the surface of the cured product layer, and the cured product layer remains entirely.
3: A state in which several to ten thick scratches are contained on the surface of the cured product layer, and the cured product layer remains entirely.
2: On the surface of the cured product layer, there are deep scratches in the area corresponding to the entire width of the steel wool, but a part of the cured product layer remains.
1: On the surface of the cured product layer, the region corresponding to the entire width of the steel wool is deeply scratched and the cured product layer is completely peeled off.

(Anti-fog)
(Breathing anti-fog)
The cured product layer of the anti-fog layer was sprayed with exhaled air for several seconds, and at this time, the presence or absence of fogging on the surface of the cured product layer was visually confirmed.
Based on the observed results, the exhaled anti-fog property was evaluated according to the following evaluation criteria.
In the following evaluation criteria, if it is A, the exhaled anti-fog property is excellent.

-Evaluation criteria for breath anti-fog property-
A: When the exhaled breath was sprayed for several seconds, the surface of the cured product layer did not become cloudy.
B: When the exhaled breath was sprayed for several seconds, the surface of the cured product layer became cloudy.

(50 ° C steam anti-fog property)
Pure water was placed in a beaker, and the pure water was heated to 50 ° C.
After the temperature of the pure water in the beaker reached 50 ° C., the anti-fog laminate was placed on the upper part of the beaker in an arrangement in which the cured product layer was in contact with water vapor, and held in this state for 1 hour. During the holding for 1 hour, the anti-fog laminate was visually observed to confirm the presence or absence of anti-fog, and the 50 ° C. steam anti-fog property was evaluated according to the following evaluation criteria.
In the following evaluation criteria, the rank with the best 50 ° C. steam anti-fog property is A.

-50 ° C steam anti-fog evaluation criteria-
A: At the completion of holding for 1 hour, the surface of the cured product layer was not fogged.
B: At the completion of holding for 1 hour, the surface of the cured product layer was cloudy, but at the completion of holding for 0.5 hours, the surface of the cured product layer was not cloudy.
C: At the completion of holding for 0.5 hours, the surface of the cured product layer was cloudy.

(Contact angle)
The contact angle of pure water on the surface of the cured product layer of the laminated body was measured using a contact angle meter (automatic contact angle meter CA-V type, manufactured by Kyowa Interface Science Co., Ltd.). The measurement was performed at three points for one sample, and the average value of these values was taken as the value of the contact angle.
The contact angles are the contact angle 1 second after the water droplets of pure water having a volume of 1.0 μL have been dropped, and the contact angles 22 seconds after the water droplets of pure water having a volume of 1.0 μL have been dropped. , Each was measured. The smaller the contact angle value, the better the anti-fog property.

<Small indentation hardness>
The photocurable composition of Example 1 is the same as the method described in <Preparation of antifogging laminate> described above, except that a magnetic stainless steel substrate is used instead of polycarbonate for attaching to the measuring device described later. The antifogging property includes a base material (that is, a base material having a laminated structure represented by "primer layer / PET film / magnetic stainless steel substrate") and a cured product layer arranged on the base material. A laminate was obtained.
The laminated structure of the anti-fog laminated body is a laminated structure represented by "cured material layer / primer layer / PET film / magnetic stainless steel substrate".
The fine indentation hardness of the obtained anti-fog laminate was measured by the above-mentioned method.
A HYSITRON TI PREMIER manufactured by Bruker was used as the measuring device, and a barco pitcher indenter was used as the measuring indenter.

[Comparative Example 1]
An antifogging laminate was produced in the same manner as in Example 1 except that the light-transmitting film arranging step was not provided and the cured product layer was formed by directly irradiating the coated material layer with ultraviolet rays (UVA).
The obtained anti-fog laminate was evaluated for scratch resistance in the same manner as in Example 1.
In Comparative Example 1, since the scratch resistance was extremely poor, each evaluation of anti-fog property and measurement of the minute indentation hardness were omitted.
The results are shown in Table 1.

[Comparative Example 2]
The composition of the photocurable composition was changed as shown in Table 1.
Did not form a primer layer,
The application method of the photocurable composition was changed to the spin coating method under the following conditions, and
An antifogging laminate was produced in the same manner as in Example 1 except that the coated layer was directly irradiated with ultraviolet rays (UVA) to form a cured product layer without performing the light transmissive film placement step. ..
The obtained anti-fog laminate was evaluated in the same manner as in Example 1.
It should be noted that, in the anti-fog laminate used for measuring the minute indentation hardness, a magnetic stainless steel substrate was used instead of the polycarbonate substrate, which is the same as in Example 1.
The results are shown in Table 1.

-Conditions for spin coating method (Comparative Example 2)-
While the laminated substrate as the base material (that is, PET film / polycarbonate substrate) is rotated at a rotation speed of 500 rpm (revolutions per minute) for 10 seconds, the photocurable composition is dropped on the surface of the laminated substrate on the PET film side. Then, the photocurable composition was spread by increasing the rotation speed of the laminated substrate to 1000 rpm and rotating it for 10 seconds to form a coating layer.

In Table 1, "% by mass in the composition" means the content (mass%) of the corresponding component with respect to the total amount of the photocurable composition, and "dry mass%" is the total amount of the photocurable composition. It means the content (% by mass) of the corresponding component with respect to the dry mass (that is, the total mass of the components other than the solvent).
"-" In Table 1 means that the corresponding component is not contained.
In Table 1, the term "solid content" for the amount of the inorganic particles (a2) means that when the inorganic particles (a2) are used in the form of the corresponding sol, the components other than the contained solvent in the mass of the sol are used. Represents the mass of.

Details of the terms listed in Table 1 are as follows.
-Polyfunctional monomer (a1)-
A-600 ... Polyethylene glycol # 600 diacrylate (manufactured by Shin Nakamura Chemical Industry Co., Ltd.).
-Inorganic particles (a2)-
PGM-AC-2140Y ... Organo silica sol (surface modification grade of propylene glycol monomethyl ether dispersed silica sol: silica particle content 42% by mass; particle diameter 10 to 15 nm; manufactured by Nissan Chemical Industries, Ltd.)
-Surfactant (a3)-
Neugen LP-100 ... Polyoxyalkylene lauryl ether (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.).
-Photopolymerization initiator-
Omnirad 127 ... (2-Hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one; IGM resin B.V. Made)
-solvent-
DEGDME ... Diethylene glycol dimethyl ether PGME ... Propylene glycol monomethyl ether

As shown in Table 1, in Example 1 in which the light transmissive film arranging step was carried out, it was possible to produce an anti-fog laminate having anti-fog property and excellent scratch resistance.
On the other hand, in Comparative Examples 1 and 2 in which the light-transmitting film arranging step was not carried out, the scratch resistance of the anti-fog laminate was lowered.

Claims (5)

A step of applying a photocurable composition on a substrate to form a coating layer, and
The step of arranging the light transmissive film on the coating material layer and
A step of irradiating the coating material layer with light through the light transmissive film to cure the coating material layer to obtain a cured product layer.
A method for producing an anti-fog laminate. The method for producing an antifogging laminate according to claim 1, wherein the step of arranging the light-transmitting film includes a step of removing a gas intervening between the light-transmitting film and the coating layer. The method for producing an antifogging laminate according to claim 1 or 2, wherein the light-transmitting film has an average transmittance of 40% or more in a wavelength region of 200 nm to 500 nm. The one according to any one of claims 1 to 3, wherein the photocurable composition contains a polyfunctional monomer having two or more (meth) acryloyl groups, inorganic particles, and a surfactant. A method for manufacturing an anti-fog laminate. With the base material
The cured product layer arranged on the substrate and
Equipped with
An anti-fog laminate having a fine indentation hardness of 0.080 GPa or more measured from the cured product layer side.