JP2021098783A - Surface protection resin member - Google Patents

Abstract

To provide a surface protection resin member having excellent transparency maintaining properties.SOLUTION: A surface protection resin member is a cured product of a composition comprising a fluorine-containing acrylic resin with a hydroxyl value of 40 mgKOH/g or more and 280 mgKOH/g or less, a polyol having a plurality of hydroxy groups, with the hydroxy groups bonded through a carbon chain with 6 or more carbon atoms, a polyfunctional isocyanate, and an aromatic heterocyclic compound.SELECTED DRAWING: None

Description

The present invention relates to a surface protective resin member.

Conventionally, in various fields, a surface protective resin member such as a surface protective film has been provided from the viewpoint of suppressing scratches on the surface. For example, a surface protective member having self-repairing property against scratches is used for an automobile interior, a protective film for building materials, a protective film for a touch panel screen, and the like.

Here, Patent Document 1 includes a "polycarbonate-based base material; and a CS-10F wear wheel containing a silicone-based hard coating layer formed on one surface of the base material and using a Taber Abraser". Resin lamination for glazing, in which the haze difference (ΔHaze) before and after wear measured according to ASTM D1003 is 4.5 or less and the water droplet contact angle is 40 ° to 60 ° in the 500 cycle test under the load condition of 500 g. "Body" is disclosed.

Patent Document 2 states, "A group comprising a base material sheet and a soft resin layer laminated on the surface of the base material sheet and having self-repairing property, and the base material sheet containing a polycarbonate resin as a main component. The material layer, the surface layer laminated on the front surface side of the base material layer and containing the polymethylmethacrylate resin as the main component, and the surface layer laminated on the back surface side of the base material layer and containing the polymethylmethacrylate resin as the main component. A self-healing film having a back surface layer containing the same and the soft resin layer containing a polyurethane resin as a main component is disclosed.

Patent Document 3 includes "polycarbonate-based base material; and a silicone-based hard coating layer formed on one surface of the base material, and has a CS-10F wear wheel using a Taber wear tester and 500 cycles under a 500 g load condition. A glazing resin laminate having a haze difference (ΔHaze) before and after wear measured according to ASTM D1003 of 4.5 or less and a water droplet contact angle of 40 ° to 60 ° at the time of testing is disclosed. ..

Japanese Unexamined Patent Publication No. 06-071826 Japanese Unexamined Patent Publication No. 2013-144391 JP-A-2015-09390

Conventionally, "a fluorine-containing acrylic resin having a hydroxyl value of 40 mgKOH / g or more and 280 mgKOH / g or less", "a polyol having a plurality of hydroxy groups and having the hydroxy group via a carbon chain having 6 or more carbon atoms" and " The surface protective resin member, which is a cured product of the composition containing "polyfunctional isocyanate", tends to have low transparency retention.
In the present invention, as compared with the surface protection resin member which is a cured product of the composition containing only the fluorine-containing acrylic resin, the polyol, the polyfunctional isocyanate, and ethyl 2-cyano-3,3-diphenylacrylate. An object of the present invention is to provide a surface protective resin member having excellent both self-repairing property and transparency maintaining property.

Specific means for solving the above problems include the following aspects.

[1] A fluorine-containing acrylic resin having a hydroxyl value of 40 mgKOH / g or more and 280 mgKOH / g or less,
A polyol having a plurality of hydroxy groups and having the hydroxy group via a carbon chain having 6 or more carbon atoms,
With polyfunctional isocyanate
Aromatic heterocyclic compounds and
A surface protective resin member which is a cured product of a composition containing.
[2] The surface protective resin member according to [1], wherein the aromatic heterocyclic compound contains a nitrogen-containing aromatic heterocyclic compound.
[3] The surface protective resin member according to [2], wherein the aromatic heterocyclic compound contains at least one of a compound having a triazine skeleton and a compound having a benzotriazole skeleton.
[4] Any one of [1] to [3], wherein the content of the aromatic heterocyclic compound is 0.05% by mass or more and 2.0% by mass or less with respect to the entire surface protective resin member. The surface protective resin member described in 1.
[5] The surface protective resin member according to [4], wherein the content of the aromatic heterocyclic compound is 0.1% by mass or more and 1.0% by mass or less with respect to the entire surface protective resin member.
[6] The ratio (B / A) of the molar amount B of the aromatic heterocyclic compound to the molar amount A of the fluorine-containing acrylic resin in the cured product is 0.02 or more and 5.00 or less [1]. ] To [5]. The surface protective resin member according to any one of [5].

According to the invention according to [1], it is a cured product of a composition containing only the fluorine-containing acrylic resin, the polyol, the polyfunctional isocyanate, and ethyl 2-cyano-3,3-diphenylacrylate. A surface protective resin member excellent in both self-repairing property and transparency maintaining property is provided as compared with the case.
According to the invention according to [2] or [3], the surface protective resin member is superior in both self-repairing property and transparency maintenance property as compared with the case where the aromatic heterocyclic compound is an oxygen-containing aromatic heterocyclic compound. Is provided.
According to the invention according to [4], the content of the aromatic heterocyclic compound is less than 0.05% by mass or more than 2.0% by mass with respect to the entire surface protective resin member, as compared with the case where the content is less than 0.05% by mass or more than 2.0% by mass. A surface protective resin member having excellent self-healing property and transparency retention property is provided.
According to the invention according to [5], the content of the aromatic heterocyclic compound is less than 0.1% by mass or more than 1.0% by mass with respect to the entire surface protective resin member, as compared with the case where the content is less than 0.1% by mass or more than 1.0% by mass. A surface protective resin member having excellent self-healing property and transparency retention property is provided.
According to the invention according to [6], the ratio (B / A) of the molar amount B of the aromatic heterocyclic compound to the molar amount A of the fluorine-containing acrylic resin in the cured product is less than 0.02 or 5 Provided is a surface protective resin member that is superior in both self-healing property and transparency retention property as compared with the case where the amount exceeds .00.

Hereinafter, embodiments of the present invention will be described. These explanations and examples illustrate the embodiments and do not limit the scope of the embodiments.

In the numerical range described stepwise in the present specification, 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 another numerical range described stepwise. Good. 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 specification, each component may contain a plurality of applicable substances.
When referring to the amount of each component in the composition in the present specification, if a plurality of substances corresponding to each component are present in the composition, the plurality of species present in the composition unless otherwise specified. Means the total amount of substances in.

As used herein, the term "self-healing" means that even if a scratch (for example, a scratch) is generated on the surface of the cured product due to contact with another substance, the scratch is repaired over time, and the original Refers to the property of being restored to the state of or close to.

-Surface protection resin member-
The surface protective resin member according to the present embodiment includes a fluorine-containing acrylic resin having a hydroxyl value of 40 mgKOH / g or more and 280 mgKOH / g or less, and a carbon having a plurality of hydroxy groups and having 6 or more carbon atoms. It is a cured product of a composition containing a polyol via a chain, a polyfunctional isocyanate, and an aromatic heterocyclic compound.

Conventionally, in a cured product of a composition containing a fluorine-containing acrylic resin, a long-chain polyol, and a polyfunctional isocyanate, a hydroxy group in a fluorine-containing acrylic resin, a hydroxy group in a long-chain polyol, and an isocyanate group in a polyfunctional isocyanate have been used. React with to form a urethane bond (-NHCOO-). In the formed urethane resin, the fluorine-containing acrylic resin forms a crosslinked structure via the polyol and the polyfunctional isocyanate, whereby self-repairing property is exhibited when it becomes a cured product.

However, the conventional surface protection resin member obtains excellent scratch resistance by being deformed by an elastic force, and is often designed to be soft. Therefore, fine scratches are likely to occur due to rubbing, contact with a chemical solvent, etc., which tends to reduce the transparency of the surface due to diffused reflection of light, that is, the transparency maintenance property tends to be lowered. In addition, the self-repair time of fine scratches generated by contact with a chemical solvent tends to be longer than the self-repair time of scratches and the like.

On the other hand, the surface protective resin member according to the present embodiment is excellent in both self-repairing property and transparency maintaining property. This factor is not always clear, but it can be inferred as follows.

The surface protective resin member according to the present embodiment is a cured product of a composition containing an aromatic heterocyclic compound in addition to a fluorine-containing acrylic resin, a long-chain polyol, and a polyfunctional isocyanate. Aromatic heterocyclic compounds tend to absorb light more efficiently than other UV absorbers (eg, non-aromatic heterocyclic compounds, non-aromatic heterocyclic compounds, etc.). .. Therefore, there is a tendency that deterioration of transparency maintenance and susceptibility to scratches due to deterioration of the cured product such as breakage of the crosslinked structure by light are suppressed. As a result, it is considered that a surface protective resin member excellent in both self-repairing property and transparency maintaining property can be obtained.

<< Properties of surface protection resin member >>
The method for forming the surface protective resin member (cured product) is not particularly limited, and a known method can be applied. A method for forming the surface protective resin member (resin polymerization method) according to the present embodiment will be described below with reference to specific examples.
For example, a liquid A containing a fluorine-containing acrylic resin, a long-chain polyol, and an aromatic heterocyclic compound, and a liquid B containing a polyfunctional isocyanate are prepared. The liquids A and B are mixed, defoamed under reduced pressure, and then cast onto a base material (for example, a resin film, an aluminum plate, a glass plate, etc.) to form a resin layer. Then, it can be formed by heating and curing.
However, in the present embodiment, the method for forming the surface protective resin member is not limited to the above method. For example, when a blocked polyfunctional isocyanate is used, it is preferable to heat it to a temperature higher than the temperature at which the block is removed to cure it. Further, a cured product may be formed by polymerization by a method such as using ultrasonic waves instead of defoaming under reduced pressure or leaving the mixed solution to defoam.

The thickness of the surface protective resin member is not particularly limited, but may be, for example, 10 μm or more and 200 μm or less, and may be 20 μm or more and 100 μm or less.

≪Composition≫
The surface protective resin member according to the present embodiment is a cured product of a composition containing a fluorine-containing acrylic resin, a long-chain polyol, another functional isocyanate, and an aromatic heterocyclic compound, which will be described later.

[Aromatic heterocyclic compound]
The composition according to this embodiment contains an aromatic heterocyclic compound.
The aromatic heterocyclic compound may be used alone or in combination of two or more.

The aromatic heterocyclic compound represents a compound containing a heterocycle having aromaticity. The aromatic heterocycle may be a compound containing at least two or more different elements in its ring structure.

Aromatic heterocyclic compounds are contained in their heterocyclic structure.
Compounds having one or more sulfur atoms (sulfur-containing aromatic heterocyclic compounds),
Compounds having one or more nitrogen atoms (nitrogen-containing aromatic heterocyclic compounds),
Compounds having one or more oxygen atoms (oxygen-containing aromatic heterocyclic compounds),
And
It may be any of compounds having two or more kinds of atoms selected from the group consisting of sulfur atoms, nitrogen atoms and oxygen atoms.

Among the above, the aromatic heterocyclic compound is contained in the heterocyclic structure from the viewpoint of making a surface protective resin member excellent in both self-repairing property and transparency maintenance property.
It preferably contains a compound having one or more nitrogen atoms (nitrogen-containing aromatic heterocyclic compound).
It is more preferable to contain a compound having 2 or more and 6 or less nitrogen atoms (nitrogen-containing aromatic heterocyclic compound).
It is more preferable to contain a compound having 3 or more and 5 or less nitrogen atoms (nitrogen-containing aromatic heterocyclic compound).

Examples of the nitrogen-containing aromatic heterocyclic compound include pyridine, triazine (specifically, 1,2,3-triazine, 1,2,4-triazine, 1,3,5-triazine, etc.) and triphenyltriazine. (2,4,6-triphenyl-1,3,5-triazole, etc.), triazole (specifically, 1,2,3-triazole, 1,2,4-triazole, etc.), benzotriazole (specifically) , 1,2,3-benzotriazole, 1,2,4-benzotriazole, etc.), melamine, diazole (specifically, imidazole, pyrazole, etc.), oxadiazol (specifically, 1,2, etc.) , 4-Oxaziazole, 1,2,5-Oxaziazole, 1,3,4-Oxaziazole, 1,2,3-Oxaziazole, etc.) and other compounds having a skeleton can be mentioned.

Among the above, the nitrogen-containing aromatic heterocyclic compound contains at least one of a compound having a triazine skeleton and a compound having a benzotriazole skeleton from the viewpoint of making a surface protective resin member excellent in both self-repairing property and transparency maintenance property. Is preferable.

The aromatic heterocyclic compound may have a substituent.
Examples of the substituent include an alkyl group having 1 to 30 carbon atoms, a hydroxy group, an aryl group having 6 to 20 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and an alkyloxycarbonyl having 2 to 30 carbon atoms. group _{(-C (= O) O-} R X, R X is an alkyl group) group containing at least one selected from the group consisting of. The alkyl group, alkoxy group and alkyloxycarbonyl group in the substituent may be linear, branched chain or cyclic.

The aromatic heterocyclic compound may be a synthetic product or a commercially available product.
Commercially available products of aromatic heterocyclic compounds include Tinuvin928, Tinuvin400, Tinuvin479, etc. manufactured by BASF Japan Ltd .; ADEKA STAB LA-46, ADEKA STAB LA-29, etc. , KEMISORB279 and the like; RUVA-93 manufactured by Otsuka Chemical Co., Ltd .; SEESORB706 manufactured by Cipro Kasei Co., Ltd. and the like.

The content of the aromatic heterocyclic compound is 0.05% by mass or more and 2.0% by mass with respect to the entire surface protection resin member from the viewpoint of making the surface protection resin member excellent in both self-repairing property and transparency maintenance property. It is preferably 0.08% by mass or more and 1.5% by mass or less, and further preferably 0.1% by mass or more and 1.0% by mass or less.

The ratio (B / A) of the molar amount B of the aromatic heterocyclic compound to the molar amount A of the fluorine-containing acrylic resin in the cured product is from the viewpoint of making the surface protective resin member excellent in both self-repairing property and transparency maintenance property. , 0.02 or more and 5 or less, more preferably 0.05 or more and 3 or less, and further preferably 0.1 or more and 1 or less.

[Fluorine-containing acrylic resin]
The composition according to the present embodiment contains a fluorine-containing acrylic resin having a hydroxyl value of 40 mgKOH / g or more and 280 mgKOH / g or less.

The composition of the present embodiment contains a fluorine-containing acrylic resin having a hydroxyl value of 40 mgKOH / g or more and 280 mgKOH / g or less.

The "fluorine-containing acrylic resin" means an acrylic resin containing a fluorine atom in its molecular structure.

The fluorine-containing acrylic resin has a hydroxy group in the structure constituting the acrylic resin. The hydroxy group is introduced, for example, by using a monomer having a hydroxy group as a monomer as a raw material for an acrylic resin. Examples of the monomer having a hydroxy group include hydroxymethyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, and N-methylol acrylicamine. , (1) Ethylene monomers having a hydroxy group and the like.
Further, (2) an ethylenic monomer having a carboxy group such as (meth) acrylic acid, crotonic acid, itaconic acid, fumaric acid, and maleic acid may be used.

A monomer having no hydroxy group may be used in combination with the monomer as a raw material of the acrylic resin. Monomers having no hydroxy group include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, n-propyl (meth) acrylate, and (meth) acrylic. (Meta) acrylic acid alkyl esters such as n-butyl acid acid, isobutyl (meth) acrylic acid, 2-ethylhexyl (meth) acrylic acid, n-octyl (meth) acrylic acid, and n-dodecyl (meth) acrylic acid, etc. Examples thereof include ethylenic monomers that can be copolymerized with the monomers (1) and (2).

As used herein, the term "(meth) acrylic acid" is a concept that includes both acrylic acid and methacrylic acid.

-Fluorine atom When a fluorine-containing acrylic resin containing a fluorine atom in the acrylic resin is used, it becomes easy to form a surface protection resin member having a high contact angle with water. That is, the self-healing property tends to be higher.
The fluorine atom can be introduced into the resin structure by using, for example, a monomer having a fluorine atom as a monomer as a raw material of an acrylic resin. Examples of the monomer having a fluorine atom include 2- (perfluorobutyl) ethyl acrylate, 2- (perfluorobutyl) ethyl methacrylate, 2- (perfluorohexyl) ethyl acrylate, 2- (perfluorohexyl) ethyl methacrylate, and perfluoro. Examples thereof include hexylethylene, hexafluoropropene, hexafluoropropene epoxiside, and perfluoro (propyl vinyl ether).

The fluorine atom is preferably contained in the side chain of the fluorine-containing acrylic resin from the viewpoint of facilitating the increase in the contact angle with water. Examples of the carbon number of the side chain containing a fluorine atom include those having 2 or more and 20 or less. The carbon chain in the side chain containing a fluorine atom may be linear or branched.
The number of fluorine atoms contained in one molecule of a monomer having a fluorine atom is not particularly limited, but is preferably 1 or more and 25 or less, and more preferably 3 or more and 17 or less.

The proportion of fluorine atoms contained in the fluorine-containing acrylic resin is preferably 1% by mass or more and 33% by mass or less, and more preferably 5% by mass or more and 20% by mass or less with respect to the entire fluorine-containing acrylic resin. preferable.
When the content ratio of fluorine atoms is 1% by mass or more, a surface protective member having a high contact angle with water can be easily obtained, and when it is 33% by mass or less, a solution having a long pot life can be easily obtained.

-Hydroxy group value The hydroxyl value of the fluorine-containing acrylic resin is 40 mgKOH / g or more and 280 mgKOH / g or less. The hydroxyl value is preferably 70 mgKOH / g or more and 210 mgKOH / g or less.
When the hydroxyl value is 40 mgKOH / g or more, a polyurethane resin having a high crosslink density tends to be obtained. On the other hand, when the hydroxyl value is 280 mgKOH / g or less, a polyurethane resin having appropriate flexibility tends to be obtained.
The hydroxyl value of the fluorine-containing acrylic resin is adjusted by the ratio of the monomer having a hydroxy group in all the monomers for synthesizing the fluorine-containing acrylic resin.

The hydroxyl value represents the number of mg of potassium hydroxide required to acetylate a hydroxyl group (hydroxy group) in 1 g of a sample.

The hydroxyl value is measured according to the method (potentiometric titration method) defined in JIS K0070-1992. However, when the measurement sample is insoluble in the solvent described in the above method, a solvent such as dioxane or tetrahydrofuran (THF) is used as the solvent.

The fluorine-containing acrylic resin is synthesized, for example, by mixing the above-mentioned monomers, performing ordinary radical polymerization, ionic polymerization, or the like, and then purifying the resin.

The weight average molecular weight Mw of the fluorine-containing acrylic resin is preferably 10,000 or more and 50,000 or less, preferably 10,000 or more and 30 or more, from the viewpoint of making the surface protective resin member excellent in both self-repairing property and transparency maintenance property. More preferably, it is 000 or less.

The weight average molecular weight is measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC is performed using a Tosoh GPC / HLC-8120GPC as a measuring device, a Tosoh column / TSKgel SuperHM-M (15 cm), and a THF solvent. The weight average molecular weight and the number average molecular weight are calculated from the measurement results using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample.

[Long chain polyol]
The composition according to the present embodiment contains a polyol having a plurality of hydroxy groups and having the hydroxy group via a carbon chain having 6 or more carbon atoms (hereinafter, also referred to as “long chain polyol”).

A long-chain polyol is a polyol having a plurality of hydroxyl groups (-OH) and having the hydroxyl group having 6 or more carbon atoms (the number of carbon atoms in the linear portion connecting the hydroxyl groups) via a carbon chain. That is, a long-chain polyol is a polyol in which all hydroxyl groups are linked by carbon chains having 6 or more carbon atoms (the number of carbon atoms in the linear portion connecting the hydroxyl groups).

The number of functional groups (that is, the number of hydroxyl groups contained in one molecule of the long-chain polyol) of the long-chain polyol may be, for example, in the range of 2 or more and 5 or less, and may be 2 or more and 3 or less.

A carbon chain having 6 or more carbon atoms in a long-chain polyol represents a chain having 6 or more carbon atoms in a linear portion connecting hydroxyl groups. As the carbon chain having 6 or more carbon atoms, one selected from an alkylene group or one or more alkylene groups and -O-, -C (= O)-, and -C (= O) -O-. A divalent group formed by combining the above groups can be mentioned. A long-chain polyol in which hydroxyl groups are linked by a carbon chain having 6 or more carbon atoms is − [CO (CH ₂ ) _n1 O] _n2 −H (where n1 is 1 or more and 10 or less (preferably 3 or more and 6). Hereinafter, it represents 5) more preferably, and n2 represents a structure of 1 or more and 50 or less (preferably 1 or more and 35 or less, more preferably 1 or more and 10 or less, still more preferably 2 or more and 6 or less). preferable.

Examples of the long-chain polyol include bifunctional polycaprolactone diol, trifunctional polycaprolactone triol, and tetrafunctional or higher functional polycaprolactone polyol.

As the bifunctional polycaprolactone diol, for example, − [CO (CH ₂ ) _n11 O] _n12 −H (where n11 represents 1 or more and 10 or less (preferably 3 or more and 6 or less, more preferably 5), n12 represents. Examples thereof include a compound having two groups having a hydroxyl group at the terminal, which is represented by 1 or more and 50 or less (preferably 3 or more and 35 or less). Of these, the compound represented by the following general formula (1) is preferable.

In the general formula (1), R represents an alkylene group or a divalent group consisting of a combination of an alkylene group and one or more groups selected from −O− and −C (= O) −, and m. And n each independently represent an integer of 1 or more and 35 or less.

In the general formula (1), the alkylene group contained in the divalent group represented by R may be linear or branched. As the alkylene group, for example, an alkylene group having 1 or more and 10 or less carbon atoms is preferable, and an alkylene group having 1 or more and 5 or less carbon atoms is more preferable.
As the divalent group represented by R, a linear or branched alkylene group having 1 or more and 10 or less carbon atoms (preferably 2 or more and 5 or less carbon atoms) is preferable, and 1 or more and 5 or less carbon atoms. A group consisting of two linear or branched alkylene groups (preferably having 1 to 3 carbon atoms) linked by -O- or -C (= O)-(preferably -O-) is preferable. .. Among _{these, * - C 2 H 4 -} *, * - C 2 H 4 OC 2 H 4 - *, or _{* -C (CH 3) 2 -} (CH 2) 2 - * a divalent represented Groups are more preferred. The divalent groups listed above are bound at the "*" portion.
m and n each independently represent an integer of 1 or more and 35 or less, preferably 2 or more and 10 or less, and more preferably 2 or more and 5 or less.

As the trifunctional polycaprolactone triol, for example,-[CO (CH ₂ ) _n21 O] _n22- H (where n21 represents 1 or more and 10 or less (preferably 3 or more and 6 or less, more preferably 5)), and n22 represents. Examples thereof include compounds having three groups having a hydroxyl group at the terminal, which are represented by 1 or more and 50 or less (preferably 1 or more and 28 or less). Of these, the compound represented by the following general formula (2) is preferable.

In the general formula (2), R is a trivalent group obtained by removing one hydrogen atom from an alkylene group, or a trivalent group obtained by removing one hydrogen atom from an alkylene group, and an alkylene group, −O−, and −. Represents a trivalent group consisting of a combination of one or more groups selected from C (= O) −. l, m, and n each independently represent an integer of 1 or more and 28 or less, and l + m + n is 3 or more and 30 or less.

In the general formula (2), when R represents a trivalent group obtained by removing one hydrogen atom from an alkylene group, the group may be linear or branched. As the trivalent group obtained by removing one hydrogen atom from the alkylene group, for example, an alkylene group having 1 or more and 10 or less carbon atoms is preferable, and an alkylene group having 1 or more and 6 or less carbon atoms is more preferable.
Further, R is a trivalent group obtained by removing one hydrogen atom from the alkylene group shown above, an alkylene group (for example, an alkylene group having 1 to 10 carbon atoms), -O-, and -C (= O). It may be a trivalent group formed by combining one or more groups selected from −.
The trivalent group represented by R is a trivalent group obtained by removing one hydrogen atom from a linear or branched alkylene group having 1 or more and 10 or less carbon atoms (preferably 3 or more and 6 or less carbon atoms). Group is preferred. Among these, * _{-CH 2-} CH (-*) -CH _2- *, CH _3- C (-*) (-*)-(CH ₂ ) _2- *, CH ₃ CH ₂ C (-*) _{(- *) (CH 2)} 3 - * 3 -valent group represented by is more preferable. The trivalent groups listed above are bound at the "*" portion.
l, m, and n each independently represent an integer of 1 or more and 28 or less, preferably 2 or more and 10 or less, and more preferably 2 or more and 5 or less. l + m + n is 3 or more and 30 or less, preferably 6 or more and 30 or less, and more preferably 6 or more and 20 or less.

As the long-chain polyol, a long-chain polyol containing a fluorine atom may be used.
The long-chain polyol containing a fluorine atom is one of the H atoms bonded to the C atom in a diol having 6 or more and 12 or less carbon atoms (for example, a diol in which two hydroxyl groups are bonded by an alkylene group having 6 or more and 12 or less carbon atoms). A long-chain diol in which some or all of them are replaced with F atoms, a polyolefin glycol having 6 or more and 12 or less carbon atoms (for example, a polyolefin glycol having 6 or more and 12 or less carbon atoms formed by a plurality of olefin glycols such as ethylene glycol and propylene glycol). ), A long-chain glycol or the like in which a part or all of the H atom bonded to the C atom is replaced with the F atom can be mentioned. Specific examples thereof include 1H, 1H, 9H, 9H-Perfluoro-1, 9-nonanediol, Fluolinated tetraceylene glycol, 1H, 1H, 8H, 8H-Perfluoro-1, 8-octanediol and the like.

In addition, only one type of long-chain polyol may be used, or two or more types may be used in combination.

The amount of the long-chain polyol added to the fluorine-containing acrylic resin is, for example, the total molar amount of all hydroxyl groups [A] contained in the fluorine-containing acrylic resin and the total molar amount of hydroxyl groups contained in the long-chain polyol [A]. The ratio [B] / [A] to [B] may be in the range of 0.1 or more and 10 or less, and may be 1 or more and 4 or less.

As the long-chain polyol, those having a hydroxyl value of 30 mgKOH / g or more and 320 mgKOH / g or less are preferably used, more preferably 50 mgKOH / g or more and 310 mgKOH / g or less, and 60 mgKOH / g or more and 300 mgKOH / g or less. Is more preferable.
It is presumed that when the hydroxyl value is 30 mgKOH / g or more, the urethane resin having a high crosslink density is polymerized, while when it is 320 mgKOH / g or less, a urethane resin having appropriate flexibility can be obtained.

The hydroxyl value represents the number of mg of potassium hydroxide required for acetylating a hydroxyl group (hydroxyl group) in 1 g of a sample. The measurement of the hydroxyl value in the present embodiment is performed according to the method (potentiometric titration method) defined in JIS K0070-1992. However, if the sample does not dissolve, a solvent such as dioxane or THF is used as the solvent.

[Polyfunctional isocyanate]
The composition according to this embodiment contains a polyfunctional isocyanate.
The polyfunctional isocyanate is a compound having a plurality of isocyanate groups (-NCO).
The polyfunctional isocyanate can form a urethane bond (-NHCOO-) by reacting with, for example, a hydroxy group contained in a fluorine-containing acrylic resin, a hydroxy group contained in a long-chain polyol, or the like. Then, it functions as a cross-linking agent for cross-linking fluorine-containing acrylic resins, fluorine-containing acrylic resins and long-chain polyols, and long-chain polyols.

Examples of the polyfunctional isocyanate include bifunctional diisocyanates such as methylene diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate; biuret structure, isocyanurate structure, adduct structure, elastic structure, etc., which are multimers of hexamethylene polyisocyanate. Multimeric isocyanate; and the like.
The polyfunctional isocyanate may be a commercially available product or a synthetic product.
Examples of commercially available products of polyfunctional isocyanate include Duranate (registered trademark) series manufactured by Asahi Kasei Corporation.
The polyfunctional isocyanate may be used alone or in combination of two or more.

The content of the polyfunctional isocyanate is not particularly limited.
Regarding the content of the polyfunctional isocyanate, for example, the ratio of the isocyanate groups contained in the polyfunctional isocyanate to the total amount of the hydroxy groups in the fluorine-containing acrylic resin and the long-chain polyol is 0.8 or more and 1.6 in terms of molar ratio. The amount is preferably adjusted to the following, and more preferably adjusted to an amount of 1 or more and 1.3 or less in terms of molar ratio.
When the amount of the polyfunctional isocyanate is adjusted so that the ratio of the isocyanate groups contained in the polyfunctional isocyanate is 0.8 or more in terms of molar ratio, the urethane resin having a high crosslink density tends to be polymerized. As a result, the self-healing property of the surface protection resin member which is a cured product to be formed tends to be further enhanced. On the other hand, when the amount of the polyfunctional isocyanate is adjusted so that the ratio of the isocyanate groups contained in the polyfunctional isocyanate is 1.6 or less in terms of molar ratio, a urethane resin having appropriate elasticity tends to be obtained.

[Other materials]
In the composition according to the present embodiment, the aromatic heterocyclic compound contains a fluorine-containing acrylic resin, a long-chain polyol, and other materials other than other functional isocyanates as long as the self-repairing property and transparency maintenance property are not impaired. May be good.
Examples of other materials include a light stabilizer, an antistatic agent, a reaction accelerator that promotes the reaction of a hydroxy group in a fluorine-containing acrylic resin and a long-chain polyol with an isocyanate group in a polyfunctional isocyanate, and the like.

-Light stabilizer Examples of the light stabilizer include hindered amine-based light stabilizers (HALS) and the like. The light stabilizer may be used alone or in combination of two or more.
Commercially available products of HALS include Tinuvin249, Tinuvin123, Tinuvin152, Tinuvin5100, Tinuvin5151 manufactured by BASF Japan Ltd .; ADEKA STAB LA-52, ADEKA STAB LA-57, ADEKA STAB LA-72, ADEKA STAB L LA-87 and the like;
Examples of HALS include 2,2,6,6-tetramethylpiperidine, 2,2,2,6-tetramethylpiperidine-1-oxyl (TEMPO), and bisdecanedioate [2,2,6,6- Tetramethyl-1- (octyloxy) piperidine-4-yl] and the like.

-Antistatic agent Examples of the antistatic agent include surfactant compounds, quaternary ammonium-containing compounds, and high molecular weight compounds. The antistatic agent may be used alone or in combination of two or more.
Examples of the surfactant include cationic surfactants (eg tetraalkylammonium salt, trialkylbenzylammonium salt, alkylamine hydrochloride, imidazolium salt, etc.) and anionic surfactant compounds (eg alkylsulfonic acid). Salts, alkylbenzene sulfonates, alkyl phosphates, etc.), nonionic surfactants (eg glycerin fatty acid esters, polyoxyalkylene ethers, polyoxyethylene alkylphenyl ethers, N, N-bis-2-hydroxyethylalkylamines) , Hydroxyalkyl monoethanolamine, polyoxyethylene alkylamine, fatty acid diethanolamide, polyoxyethylene alkylamine fatty acid ester, etc.), amphoteric surfactant compounds (eg, alkylbetaine, alkylimidazolium betaine, etc.) and the like.

Examples of the quaternary ammonium-containing compound include tri-n-butylmethylammonium bistrifluoromethanesulfonimide, lauryltrimethylammonium chloride, octyldimethylethylammonium ethyl sulfate, didecyldimethylammonium chloride, lauryldimethylbenzylammonium chloride, and stearyldimethylhydroxy. Examples thereof include ethylammonium paratoluene sulfonet, tributylbenzylammonium chloride, lauryldimethylaminoacetic acid betaine, lauric acid amide propyl betaine, octanoate amide propyl betaine, and hydrochloride of polyoxyethylene stearylamine. Among these, tri-n-butylmethylammonium bistrifluoromethanesulfonimide is preferable.

Examples of the high molecular weight compound include a polymer compound obtained by polymerizing a quaternary ammonium base-containing acrylate, a polystyrene sulfonic acid type polymer compound, a polycarboxylic acid type polymer compound, a polyether ester type polymer compound, and an ethylene oxide-epicchlorohydrin type high molecular weight compound. Examples thereof include molecular compounds and polyether ester amide type polymer compounds.

Examples of the polymer compound obtained by polymerizing the quaternary ammonium base-containing acrylate include a polymer compound having at least the following structural units.

(In the structural unit, R ¹ represents a hydrogen atom or a methyl group, R ² , R ³ and R ⁴ each independently represent an alkyl group, and X ⁻ represents an anion.)

-Reaction accelerator Examples of the reaction accelerator that promotes the reaction between the hydroxy group in the fluorine-containing acrylic resin and the long-chain polyol and the isocyanate group in the polyfunctional isocyanate include metal catalysts of tin and bismuth. For example, there are Neostan U-28, U-50, U-600, U-100, U-200, U-810, tin stearate (II) of Nitto Kasei Co., Ltd. Examples thereof include XC-C277, XK-640, XK-628, 348, XC-C227, etc. of Kusumoto Kasei Co., Ltd., Borchi Kat 315, Borchi Kat 320, Borchi Kat 24, Mitsubishi Chemical Corporation, etc. .. The reaction accelerator may be used alone or in combination of two or more.

≪Use≫
The surface protection resin member according to the present embodiment can be used, for example, as a surface protection member for a material that is required to have both self-repairing property and transparency maintenance property for self-repairing surface scratches generated by contact with a substance. it can.
Specifically, automobile parts (for example, car interiors, car bodies, door handles, etc.), building materials (for example, floor materials, tiles, wall materials, wallpaper, etc.), portable devices (for example, smartphones, mobile phones, portable games, etc.) Screens and bodies other than screens, touch panel screens, storage containers (eg suitcases), cosmetic containers, glasses (eg frames, lenses, etc.), sporting goods (eg golf clubs, rackets, etc.), writing utensils (For example, a pen, etc.), musical instruments (for example, the exterior of a piano, etc.), clothing storage tools (for example, hangers, etc.), leather products (for example, bags, land cells, etc.), decorative films, film mirrors, copiers, and other members for image forming devices. (For example, a transfer member such as a transfer belt) and the like.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to the following Examples. The materials, amounts used, proportions, treatment procedures, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present disclosure. Unless otherwise specified, "part" means "part by mass".

≪Preparation of materials≫
(Synthesis of fluorine-containing acrylic resin)
(1) Fluorine-containing acrylic resin with a hydroxyl value of 175 mgKOH / g 1
25:30: 5 mol of each polymerizable monomer of n-butyl methacrylate (nBMA), hydroxyethyl methacrylate (HEMA), and an acrylic monomer having a perfluoro group (FAMAC6, manufactured by Unimatec Co., Ltd.). Mixed by ratio. Further, a polymerization initiator (azobisisobutyronitrile (AIBN)) having a ratio of 2% by mass of the polymerizable monomer and methyl ethyl ketone (MEK) having a ratio of 40% by mass of the polymerizable monomer are added to make the polymer polymerizable. A monomeric solution was prepared.
This polymerizable monomer solution was placed in a dropping funnel, and was dropped over 3 hours under stirring in MEK having a ratio of the polymerizable monomer to 50% by mass, which was heated to 80 ° C. under nitrogen reflux and polymerized. Further, a liquid composed of MEK having a ratio of 10% by mass of the polymerizable monomer and AIBN having a ratio of 0.5% by mass of the polymerizable monomer was added dropwise over 1 hour to complete the reaction. During the reaction, the temperature was maintained at 80 ° C. and stirring was continued. In this way, the fluorine-containing acrylic resin 1 was synthesized.
When the hydroxyl value of the obtained fluorine-containing acrylic resin 1 was measured according to the method (potentiometric titration method) specified in JIS K0070-1992, the hydroxyl value was 175 mgKOH / g. When the weight average molecular weight of the fluorine-containing acrylic resin 1 was measured by the above-mentioned method using gel permeation chromatography (GPC), the weight average molecular weight was 17,000. The molar ratio of the side chain having fluorine (perfluoro group) to the total side chain of the fluorine-containing acrylic resin 1 was 8.3%.

(2) Fluorine-containing acrylic resin with a hydroxyl value of 200 mgKOH / g 2
In the method for synthesizing the fluorine-containing acrylic resin 1, the same operation as the method for synthesizing the fluorine-containing acrylic resin 1 is performed except that the respective polymerizable monomers are mixed at a molar ratio of 20:35: 5. , A fluorine-containing acrylic resin 2 having a hydroxyl value of 200 mgKOH / g was obtained.
The fluorine-containing acrylic resin 2 had a weight average molecular weight of 18,000. The molar ratio of the side chain having fluorine (perfluoro group) to the total side chain of the fluorine-containing acrylic resin 2 was 8.4%.

(Long chain polyol)
-Long chain polyol 1 (polycaprolactone triol, Praxel 308, manufactured by Daicel Corporation, molecular weight 850, hydroxyl value 200 mgKOH / g)
-Long chain polyol 2 (polycaprolactone triol, product number Praxel 312, manufactured by Daicel Corporation, molecular weight 1250, hydroxyl value 135 mgKOH / g)

(Short chain polyol)
Short-chain polyol 1 (polyol having a plurality of hydroxy groups and having the hydroxy group via a carbon chain having 5 or less carbon atoms; 1,2,4-pentantriol, hydroxyl value 1400 mgKOH / g)

(Polyfunctional isocyanate)
-Polyfunctional isocyanate 1 (multimer of hexamethylene diisocyanate (isocyanurate structure), duranate TPA-100, manufactured by Asahi Kasei Chemicals Co., Ltd.)

(Aromatic heterocyclic compound)
-Aromatic heterocyclic compound 1 (hydroxyphenyltriazine compound, Tinuvin479, manufactured by BASF Japan Ltd.)
-Aromatic heterocyclic compound 2 (2- [4-([2-Hydroxy-3-dodecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5- A mixture of triazine and 2- [4-([2-Hydroxy-3-tridecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, Tinuvin400, Made by BASF Japan Co., Ltd.)

(Ultraviolet visible absorption compound having no aromatic heterocycle)
-Ethyl 2-cyano-3,3-diphenylacrylate (Product name Ubinal 3035, manufactured by BASF Limited)

(Light stabilizer)
-Light stabilizer 1 (NR type hindered amine compound, Tinuvin 249, manufactured by BASF Japan Ltd.)
-Light stabilizer 2 (N-OR type hindered amine compound, Tinuvin123, manufactured by BASF Japan Ltd.)

[Examples 1 to 6 and Comparative Examples 1 to 6]
A material other than the polyfunctional isocyanate shown in Table 1, inorganic bismuth (Neostan U-600, manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst, and methyl ethyl ketone as a solvent were mixed and stirred to obtain a mixture. Subsequently, polyfunctional isocyanate was added to the mixture in the amount shown in Table 1 and stirred to prepare a solution for forming a surface protective resin member.

The solution for forming the surface protective resin member of each example obtained above was applied on a polycarbonate film (base material) having a thickness of 2 mm with a wire bar. Then, this was dried and cured at 80 ° C. for 1 hour to prepare a surface protective resin member containing a cured film having an average film thickness of 60 μm.

[Evaluation 1 / Transparency maintenance 1]
The surface of the surface protective resin member of each example was rubbed with a brass brush in an environment of 25 ° C. at a speed of 0.1 N and 10 cm / s. Then, after allowing to stand in a 25 ° C. and 50% RH environment for one day, the total light transmittance of the rubbed portion is measured with a haze meter (NDH-2000 manufactured by Nippon Denshoku Kogyo Co., Ltd.). From the relationship between the obtained total light transmittance and the scattered light, the haze value (cloudiness) was obtained by "haze value (%) = scattered light / total light transmittance × 100" and evaluated according to the following criteria. It should be noted that G1 to G2 are acceptable. The results are shown in Table 1.
G1: The haze value is 2% or less, and the transparency is excellent.
G2: The haze value is less than 2% and 5% or less, and has transparency retention.
G3: The haze value exceeds 5%, and the transparency maintenance property is low.

[Evaluation 2 / Transparency maintenance 2]
The surface of the surface protection resin member of each example was immersed in a basic aqueous solution of pH 9 in an environment of 25 ° C. for 1 week. Then, the total light transmittance of the immersed portion is measured with a haze meter (NDH-2000 manufactured by Nippon Denshoku Kogyo Co., Ltd.). From the relationship between the obtained total light transmittance and the scattered light, the haze value (cloudiness) was obtained by "haze value (%) = scattered light / total light transmittance × 100" and evaluated according to the following criteria. It should be noted that G1 to G2 are acceptable. The results are shown in Table 1.
G1: The haze value is 2% or less, and the transparency is excellent.
G2: The haze value is less than 2% and 5% or less, and has transparency retention.
G3: The haze value exceeds 5%, and the transparency maintenance property is low.

[Evaluation 3 / Transparency maintenance 3]
The surface protective resin member of each example is allowed to stand in a 25 ° C. and 50% RH environment for 3 months, and then the total light transmittance is measured with a haze meter (NDH-2000 manufactured by Nippon Denshoku Kogyo Co., Ltd.). From the relationship between the obtained total light transmittance and the scattered light, the haze value (cloudiness) was obtained by "haze value (%) = scattered light / total light transmittance × 100" and evaluated according to the following criteria. It should be noted that G1 to G2 are acceptable. The results are shown in Table 1.
G1: The haze value is 2% or less, and the transparency is excellent.
G2: The haze value is less than 2% and 5% or less, and has transparency retention.
G3: The haze value exceeds 5%, and the transparency maintenance property is low.

[Evaluation 4 / Self-healing]
The surface of the cured film in the surface protective resin member of each example was scratched by reciprocating a width of 3 cm twice at 10 cm / s while pressing a brass brush under a load of 0.1 N under an environment of 25 ° C. Then, in an environment of 25 ° C., the repair time until the created scratches were repaired was measured. In addition, "the scratch is repaired" means the time from the time when the scratch is made to the time when it cannot be visually confirmed. After that, each repair time was evaluated according to the following criteria. Acceptable are G1 and G2. The results are shown in Table 1.
G1: The scratch was repaired within 1 day.
G2: Scratches were repaired over a day and within a week.
G3: Scratches were not repaired for more than a week.

In Comparative Example 1 shown by * 1 in Table 1, the surface protective resin member was not provided and the base material was left as it was.
In Comparative Example 2 shown by * 2 in Table 1, the surface protective resin member made of the above-mentioned silicone-based coating agent was used.
In Comparative Example 3 shown by * 3 in Table 1, a surface protective resin member made of a urethane resin containing an acrylic resin having no fluorine atom was used.
In Comparative Example 4 shown by * 4 in Table 1, "short-chain polyol 1" was used instead of "long-chain polyol".
In Comparative Example 6 shown by * 5 in Table 1, "ultraviolet visible absorption compound having no aromatic heterocycle" was used instead of "aromatic heterocyclic compound".
In Table 1, "B / A" represents the ratio (B / A) of the molar amount B of the aromatic heterocyclic compound to the molar amount A of the fluorine-containing acrylic resin in the cured product.

As shown in Table 1, it was found that the surface protective resin member of the example had self-repairing property. Further, it was found that the surface protective resin member of the example was superior in transparency maintenance property as compared with the surface protective resin member of the comparative example.

Claims (6)

Fluorine-containing acrylic resin having a hydroxyl value of 40 mgKOH / g or more and 280 mgKOH / g or less,
A polyol having a plurality of hydroxy groups and having the hydroxy group via a carbon chain having 6 or more carbon atoms,
With polyfunctional isocyanate
Aromatic heterocyclic compounds and
A surface protective resin member which is a cured product of a composition containing. The surface protective resin member according to claim 1, wherein the aromatic heterocyclic compound contains a nitrogen-containing aromatic heterocyclic compound. The surface protective resin member according to claim 2, wherein the aromatic heterocyclic compound contains at least one of a compound having a triazine skeleton and a compound having a benzotriazole skeleton. The invention according to any one of claims 1 to 3, wherein the content of the aromatic heterocyclic compound is 0.05% by mass or more and 2.0% by mass or less with respect to the entire surface protective resin member. Surface protection resin member. The surface protective resin member according to claim 4, wherein the content of the aromatic heterocyclic compound is 0.1% by mass or more and 1.0% by mass or less with respect to the entire surface protective resin member. Claims 1 to claim that the ratio (B / A) of the molar amount B of the aromatic heterocyclic compound to the molar amount A of the fluorine-containing acrylic resin in the cured product is 0.02 or more and 5.00 or less. Item 5. The surface protective resin member according to any one of Item 5.