JP7266858B2 - Filler particles, film-forming composition, article with film, molding resin material and molded article - Google Patents

Description

TECHNICAL FIELD The present invention relates to filler particles, a film-forming composition, an article provided with a film, a resin material for molding, and a molded product. More specifically, specific filler particles, a film-forming composition containing the filler particles, an article having a film formed using the film-forming composition, and a molding resin material containing the specific filler particles and a molded article formed using the molding resin material.

Compositions containing filler particles are known as film-forming compositions such as paints and coating agents. Inorganic particles such as silica are known as general-purpose filler particles.
Filler particles are added to the film-forming composition for the purpose of, for example, improving the scratch resistance and hardness of the film.

As an example, in Patent Document 1, a compound having an alkoxysilyl group and an unsaturated double bond is reacted with a metal oxide particle having a functional group capable of reacting with the alkoxysilyl group on its surface. Particles are described. Further, Patent Document 1 describes that a cured coating film having excellent transparency and scratch resistance can be obtained by including the particles in a coating agent.

As another example, in the examples of Patent Document 2, (1) a silane compound such as perfluorooctyltriethoxysilane, octyltriethoxysilane, or octyltrimethoxysilane was used to modify the surface of nano-sized silica particles. and (2) the addition of silica particles whose surface has been modified to the coating agent. Moreover, Patent Document 2 describes that the use of this coating agent to form a coating improves scratch resistance and scratch resistance.

JP 2005-220243 A Japanese Patent Publication No. 2005-528505

The particle size of the particles (filler particles) described in Patent Documents 1 and 2 is relatively small.
For example, since Patent Document 1 describes that a cured coating film having excellent "transparency" can be obtained, the particle size of the particles is considered to be equal to or less than the wavelength of visible light.

On the other hand, from the viewpoint of scratch resistance, it is considered preferable that the particle size of the filler particles is large to some extent. This is because if the particle size is too small, it may not be possible to prevent scratches and dents by the action of the filler particles alone.

However, when the particle diameter of the filler particles is increased, the filler particles tend to settle during film formation, and the existence ratio of the filler particles near the surface of the film decreases. Therefore, it tends to be difficult to obtain the effect of scratch resistance by adding filler particles.

The present invention has been made in view of such circumstances. One of the objects of the present invention is to provide filler particles which, despite having a relatively large particle size, are less likely to settle during film formation.

As a result of intensive studies, the inventors of the present invention completed the invention provided below and solved the above problems.

According to the invention, the following are provided.

一般式（１）において、
２つのＲは、互いに独立に、水素原子、１価の有機基または下記一般式（２）で表される基であり、かつ、２つのＲのうち少なくとも１つは下記一般式（２）で表される基であり、
Ｌは、２価の連結基であり、
＊は、他の化学構造との連結手である。

一般式（２）において、
Ｒ^１は、直鎖または分岐の炭素数４以上のアルキル基を含む基、ケイ素原子含有基またはフッ素原子含有基であり、
Ｒ^２は、水素原子またはメチル基である。 modified with a group containing a structure represented by the following general formula (1),
Filler particles whose primary particles have an average particle size of 0.4 to 3 μm based on electron microscopic observation.

In general formula (1),
Two R are, independently of each other, a hydrogen atom, a monovalent organic group or a group represented by the following general formula (2), and at least one of the two R is represented by the following general formula (2) is a group represented by
L is a divalent linking group,
* is a linker with other chemical structures.

In general formula (2),
R ¹ is a group containing a linear or branched alkyl group having 4 or more carbon atoms, a silicon atom-containing group or a fluorine atom-containing group,
^R2 is a hydrogen atom or a methyl group.

Moreover, according to the present invention,
A film-forming composition comprising the above filler particles is provided.

Moreover, according to the present invention,
An article is provided having a film formed using the film-forming composition described above.

Moreover, according to the present invention,
A molding resin material is provided that includes the filler particles described above and a thermoplastic resin.

Moreover, according to the present invention,
A molded article formed using the molding resin material is provided.

ADVANTAGE OF THE INVENTION According to this invention, although the particle diameter is comparatively large, the filler particle which is hard to sediment at the time of film formation is provided. Moreover, by using the film-forming composition containing the filler particles, a film having good scratch resistance can be formed.

1 is an image obtained by observing the surface of a film formed using a film-forming composition with a laser microscope. 1 is an image obtained by observing the surface of a film formed using a film-forming composition by EDS (energy dispersive X-ray spectroscopy).

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In this specification, the notation "a to b" in the description of numerical ranges means from a to b, unless otherwise specified. For example, "1 to 5% by mass" means "1% by mass or more and 5% by mass or less".
In the description of a group (atomic group) in the present specification, a description without indicating whether it is substituted or unsubstituted includes both those having no substituent and those having a substituent. For example, the term “alkyl group” includes not only alkyl groups without substituents (unsubstituted alkyl groups) but also alkyl groups with substituents (substituted alkyl groups).
The notation "(meth)acryl" used herein represents a concept that includes both acryl and methacryl. The same applies to similar notations such as "(meth)acrylate".
The term "organic group" as used herein means an atomic group obtained by removing one or more hydrogen atoms from an organic compound, unless otherwise specified. For example, a "monovalent organic group" represents an atomic group obtained by removing one hydrogen atom from an arbitrary organic compound.

<Filler particles>
The filler particles of this embodiment are modified with a group containing a structure represented by the following general formula (1). In other words, the surface of the filler particles of this embodiment has a chemical structure represented by the following general formula (1).
Further, the average particle size of the primary particles of the filler particles of the present embodiment is 0.4 to 3 μm based on electron microscopic observation.

In general formula (1),
Two R are, independently of each other, a hydrogen atom, a monovalent organic group or a group represented by the following general formula (2), and at least one of the two R is represented by the following general formula (2) is a group represented by
L is a divalent linking group,
* is a linker with other chemical structures.

一般式（２）において、
Ｒ^１は、直鎖または分岐の炭素数４以上のアルキル基を含む基、ケイ素原子含有基、または、フッ素原子含有基であり、
Ｒ^２は、水素原子またはメチル基である。
ここで、Ｒ^１が、直鎖または分岐の炭素数４以上のアルキル基を「含む基」であるとは、Ｒ^１が、直鎖または分岐の炭素数４以上のアルキル基そのものであるか、または、Ｒ^１が、直鎖または分岐の炭素数４以上のアルキル基を部分構造として含む基であることを意味する。
以下では、「直鎖または分岐の炭素数４以上のアルキル基」を「特定アルキル基」とも表記する。

In general formula (2),
R ¹ is a group containing a linear or branched alkyl group having 4 or more carbon atoms, a silicon atom-containing group, or a fluorine atom-containing group;
^R2 is a hydrogen atom or a methyl group.
Here, the expression that R ¹ "is a group containing" a linear or branched alkyl group having 4 or more carbon atoms means that R ¹ is itself a linear or branched alkyl group having 4 or more carbon atoms, Alternatively, it means that R ¹ is a group containing a linear or branched alkyl group having 4 or more carbon atoms as a partial structure.
Hereinafter, a "linear or branched alkyl group having 4 or more carbon atoms" is also referred to as a "specific alkyl group".

In the filler particles of the present embodiment, R ¹ is a group containing a specific alkyl group, a silicon atom-containing group, or a fluorine atom-containing group. In particular, due to the presence of this ^R1 , even if the average particle size of the primary particles is relatively large at 0.4 to 3 μm, the filler particles are less likely to settle during film formation (the filler tends to be present at the top of the film). Become). As a result, a film having good scratch resistance can be formed.

As can be seen from the fact that "silicon-based surfactants" and "fluorine-based surfactants" are known, the filler particles are provided with a silicon-atom-containing group or a fluorine-atom-containing group (R ¹ is a silicon-atom-containing group or a fluorine atom-containing group), the filler particles tend to be present on the upper portion of the film (on the surface or near the surface). That is, it becomes difficult for the filler particles to settle.

Further, the specific alkyl group is considered to contribute to making it difficult for the filler particles to settle for thermodynamic reasons. Specifically, it is as follows.
A specific alkyl group can assume various conformations due to free rotation of the CC bond. Therefore, from the viewpoint of entropy, it is advantageous for the alkyl group to appear on the surface of the film rather than inside the film and allow relatively free (random) thermal movement. It is believed that this makes it difficult for the filler particles to settle during film formation.

From another point of view, it can be said that the amount of filler particles used in preparing the film-forming composition can be relatively reduced because the filler particles are less likely to settle during film formation.
Reducing the amount of filler particles used directly leads to cost reduction. Moreover, since the amount of particles in the film can be reduced, it is easy to obtain a transparent film even if filler particles are used. This means that the filler particles of the present embodiment can also be applied to a so-called clear paint (a clear paint is a pigment-free, substantially transparent paint. It is usually used to form a transparent coating film thereon while maintaining the design of the base material or the colored underlayer film.).

By the way, especially the chemical structure represented by general formula (2) can be formed by a relatively simple chemical reaction. In this respect, the filler particles of the present embodiment can be said to be relatively preferable in terms of industrial productivity and cost (a specific method for forming the chemical structure represented by the general formula (2) will be described later. do).

The filler particles of this embodiment will be described in more detail below.

(Description of general formulas (1) and (2))
In general formula (1), when R is not a group represented by general formula (2), R is a hydrogen atom or a monovalent organic group. Examples of monovalent organic groups here include alkyl groups, cycloalkyl groups, alkoxy groups, aryl groups, aralkyl groups, alkylcarbonyl groups, alkoxycarbonyl groups, and alkylcarbonyloxy groups.
Although the number of carbon atoms in the monovalent organic group is not particularly limited, it is, for example, 1-20, specifically 1-10.
From the viewpoint of making the filler particles more difficult to sink, R is preferably a group containing a linear or branched alkyl group having 4 or more carbon atoms, and is a linear or branched alkyl group having 4 or more carbon atoms. is more preferred.

From the viewpoint of making the filler particles less likely to sink, both of the two R's in general formula (1) are preferably groups represented by general formula (2).

In the general formula (1), the divalent linking group of L is, for example, an alkylene group (which may be linear or branched), an alicyclic group (which may be monocyclic or polycyclic), an aromatic group, an ether groups, ester groups, thioether groups, sulfide groups, carbonyl groups, amide groups (—CONH—), —NH— groups, and groups in which two or more of these are linked.
The number of carbon atoms in L as a whole is not particularly limited. For example, when L is an alkylene group, it preferably has 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms. When L is an alicyclic group, it preferably has 3-12 carbon atoms. When L is an aromatic group, it preferably has 6-20 carbon atoms.

L is (i) an alkylene group, or (ii) at least one selected from the group consisting of an ether group, an ester group, a thioether group, a sulfide group, a carbonyl group, a -NH- group and an amide group (-CONH-). It is preferably a group in which two groups and an alkylene group are linked.

In general formula (2), when R ¹ is a group containing a specific alkyl group, the specific alkyl group includes n-butyl, isobutyl, pentyl, neopentyl, isopentyl, hexyl, heptyl, and octyl. group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group, isolauryl group, isostearyl group, isocetyl group, octyldodecyl group, myristyl group, 2-ethylhexyl group, 2-hexyldecyl group, 2-decylmyristyl group, 2,7-dimethylhexadecyl group, isotridecyl group, 2,2-dimethyllauryl group, 2,3-dimethyllauryl group, 2,2-dimethylstearyl group, 2,3-dimethylstearyl group and the like can be mentioned. Of course, the specific alkyl groups are not limited to these.
R ¹ is preferably the specific alkyl group itself (not a group containing a specific alkyl group as a partial structure, but a specific alkyl group as a whole) from the viewpoint of availability of materials, ease of production, and the like.

In the general formula (2), when R ¹ is a silicon atom-containing group, examples of R ¹ include a group containing an alkylsilyl group, a group containing a polysiloxane structure, a group containing a cyclic siloxane structure, silsesquioxane Groups containing (ladder-type, cage-type) structures and the like can be mentioned.
Among these, a group containing an alkylsilyl group or a group containing a polysiloxane structure is preferable from the viewpoint of availability of raw materials. Here, more specifically, the polysiloxane structure includes a polydialkylsiloxane structure such as a polydimethylsiloxane structure (—Si(CH ₃ ) ₂ —O—), a polydiphenylsiloxane structure (—Si(C ₆ H ₅ ) ₂ —O—) and the like can be preferably mentioned.

In general formula (2), specific examples of R ¹ being a fluorine atom-containing group include a fluorine-substituted alkyl group, a fluorine-substituted cycloalkyl group, a fluorine-substituted alkoxy group, a fluorine-substituted aryl group, a fluorine-substituted aralkyl group, and a fluorine-substituted A substituted alkylcarbonyl group, a fluorine-substituted alkoxycarbonyl group, a fluorine-substituted alkylcarbonyloxy group, and the like can be mentioned.
The fluorine atom-containing group for R ¹ may be one in which all hydrogen atoms are substituted with fluorine atoms (perfluoro group), or one in which only some of the hydrogen atoms are substituted with fluorine atoms. good too. From the viewpoint of making the filler particles more difficult to settle, it is preferable that 50 mol % or more of the hydrogen atoms in the fluorine atom-containing group of R ¹ are substituted with fluorine atoms.

R ¹ is preferably a group containing a branched alkyl group or a group containing a polydimethylsiloxane structure in view of the difficulty of sedimentation, compatibility with other components when preparing a film-forming composition, and the like.

(Material/material of filler particles)
Filler particles are typically inorganic particles. In other words, the filler particles can be said to be inorganic particles modified with a group containing at least the structure represented by general formula (1).
Examples of inorganic particles include various materials known as filler materials in the fields of paints and coating agents. Inorganic particles can be, for example, oxides, nitrides, hydroxides, inorganic salts, and the like.
Some surface treatment may be applied to the inorganic particles. For example, the inorganic particles may further have a modified structure different from the group containing the structure represented by general formula (1).

The filler particles are preferably at least one inorganic particles selected from the group consisting of aluminosilicate particles, alumina particles and silica particles modified with a group having a structure represented by the general formula (1). be. These are preferable in terms of availability, cost, easiness of surface modification, compatibility with other components when preparing a film-forming composition, good scratch resistance, and the like.

Usable aluminosilicate particles are not particularly limited. For example, the aluminosilicate particles can be amorphous or crystalline. Examples of commercially available aluminosilicate particles include Shilton JC and Shilton AMT (trade names) manufactured by Mizusawa Chemical Industry Co., Ltd. These are amorphous aluminosilicates.

Alumina particles that can be used are not particularly limited. Although the crystal structure of alumina is not particularly limited, it is usually α-alumina. Alumina particles can be, for example, spherical alumina obtained by reacting metal aluminum with oxygen, spherical alumina obtained by melting crushed alumina, crushed alumina, and the like. Alumina particles are available from Nippon Light Metal Co., Ltd., Admatechs Co., Ltd., and the like.

Usable silica particles are not particularly limited. Silica particles are roughly classified into those produced by a dry method and those produced by a wet method. The dry method is further classified into the combustion method and the arc method. Wet methods are further classified into sedimentation methods and gel methods.
As another aspect, the silica particles may be fumed silica or colloidal silica. As another aspect, the silica particles may be natural products or synthetic products.
Silica particles are available from Tosoh Silica Co., Ltd., Nippon Aerosil Co., Ltd., DSL. It is available from Japan Co., Ltd., Admatechs Co., Ltd., Fuji Silysia Chemical Co., Ltd., Evonik, and the like.

(Regarding particle size)
The average particle size of the primary particles of the filler particles may be 0.4 to 3 μm, preferably 0.5 to 2.0 μm, more preferably 0.6 to 1.5 μm. By setting the average particle diameter of the primary particles to an appropriate value, it is possible to further improve the abrasion resistance while making it difficult for the filler particles to settle.

From another point of view, the proportion of primary particles having a particle size of 0.4 μm or less in the filler particles is preferably 10% or less, more preferably 5% or less. Scratch resistance can be further enhanced by not only increasing the average particle size, but also by decreasing the proportion of filler particles that are small in the particle size distribution.

From another point of view, the ratio of primary particles having a particle size of 2.8 μm or more on the number basis in the filler particles is preferably 20% or less, more preferably 10% or less. It is considered that the sedimentation of the filler particles as a whole is further suppressed because the proportion of coarse particles in the filler particles is small. In addition, it is preferable to have few coarse particles from the viewpoint of improving the smoothness of the film and reducing the haze of the film.

The average particle size of the primary particles of the filler particles and the particle size distribution of the filler particles are adjusted, for example, by selecting raw material particles having an appropriate particle size and particle size distribution, or by centrifugally classifying the filler particles. can do.

Here, a method for measuring the particle size will be described.
In this specification, the particle size of filler particles is obtained based on an image taken with an electron microscope. For example, the particle size can be obtained by the following procedure.
(1) Filler particles are dispersed as much as possible with ultrasonic waves using a suitable solvent such as methyl ethyl ketone as a dispersion medium to obtain a dispersion liquid.
(2) The above dispersion is dropped onto a sample stage, and the solvent is dried under normal temperature and pressure to obtain a sample for particle size measurement.
(3) When using an SEM (scanning electron microscope) as an electron microscope, the sample surface is coated (about 10 nm) by a sputtering method or a vapor deposition method.
(4) Take an image of the sample with an electron microscope. When using the SEM, the acceleration voltage is set to, for example, about 25 kV.
(5) Measure the equivalent perfect circle diameter of 100 particles judged to be primary particles (particles that are not agglomerated) from the image photographed in (4) above. Here, the equivalent perfect circle diameter is the diameter of a perfect circle having the same area as the particle in the image.
(6) Based on the numerical data obtained in (5) above, the average particle size of primary particles, the ratio of primary particles with a particle size of 0.4 μm or less, the ratio of primary particles with a particle size of 2.8 μm or more, etc. are determined.

Incidentally, when the particle diameter of the filler particles in the film-forming composition or the particle diameter of the filler particles in the film is to be obtained, for example, the particle diameter is measured by omitting the above (1) and (2). can be considered.

(Manufacturing method of filler particles)
A method for producing the filler particles is not particularly limited. For example, it can be produced in the following first and second steps. In Examples 3, 4 and 5 of the examples given later, filler particles are generally obtained by such a two-step process.

First Step First, raw material particles (inorganic particles, etc.) are reacted with a silane coupling agent represented by the following general formula (1a) to introduce a —NH ₂ structure on the surface of the raw material particles.

In general formula (1a),
When multiple R ³ are present, they are each independently an alkyl group or an acyl group,
R ⁴ is each independently an alkyl group when there are more than one,
m is an integer of 1 to 3, n is an integer of 0 to 2, m+n is 3,
L is a divalent linking group.

The carbon number of R ³ is preferably 1-10, more preferably 1-4.
Specific examples of R ³ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group and heptyl. group, an octyl group, a nonyl group, an alkyl group such as a decyl group, an acyl group represented by -CO-R'(R' is, for example, any of the alkyl groups listed here), and the like. .
R ³ is preferably a methyl group or an ethyl group, particularly preferably a methyl group.

The carbon number of R ⁴ is preferably 1-10, more preferably 1-4.
Specific examples of R ⁴ include the alkyl groups listed as specific examples of R ³ .
R ⁴ is preferably a methyl group or an ethyl group, particularly preferably a methyl group.

m is preferably 2 or 3, more preferably 3.
n is preferably 0 or 1, more preferably 0.

Specific examples of the divalent linking group for L are the same as those for L in formula (1).

• Second step A compound having a specific alkyl group-containing group, a silicon atom-containing group, or a fluorine atom-containing group is bonded to the —NH ₂ introduced onto the surface of the raw material particles. More specifically, a compound represented by general formula (2a) below is subjected to Michael addition to —NH ₂ introduced onto the surface of the raw material particles. As a result, the carbon-carbon double bond portion of the compound represented by the general formula (2a) reacts with —NH ₂ to bond.

The definitions and specific examples of R ¹ and R ² in general formula (2a) are the same as in general formula (2).

In the second step, by adjusting the amount of the compound represented by the general formula (2a), one or both of R in the general formula (1) to obtain filler particles represented by the general formula (2). can be done. In principle, by reacting 2 mol or more of the compound represented by general formula (2a) with 1 mol of —NH ₂ , both R in general formula (1) are represented by general formula (2). It is possible to obtain filler particles which are the groups to be treated.

In the above, in the first step, the raw material particles and the silane coupling agent represented by the general formula (1a) were reacted, and in the second step, the compound represented by the general formula (2a) was subjected to Michael addition.
Apart from such a procedure, (i) first, the silane coupling agent represented by the general formula (1a) is reacted with the compound represented by the general formula (2a), (ii) then ( The filler particles may be produced by reacting the reactant obtained in i) with raw material particles. In the examples below, the procedures described in Examples 1, 2 and 6 apply to this procedure.

<Film-forming composition>
The film-forming composition of the present embodiment contains the filler particles described above.
The content of the filler particles in the film-forming composition is preferably 0.5 to 10% by mass, more preferably 0.8 to 5% by mass, based on the non-volatile components of the composition. When the content is 0.5% by mass or more, the effects (for example, scratch resistance) of using the filler particles can be sufficiently obtained. When the content is 10% by mass or less, the ratio of film-forming components (for example, polymerizable compounds and resins described later) can be sufficiently increased, and the coating properties and film-forming properties can be further improved. .

The film-forming composition is not particularly limited as long as it can form a film containing filler particles.
As an example, the film-forming composition contains a resin in addition to filler particles.
As another example, the film-forming composition includes a polymerizable compound and a photoinitiator in addition to filler particles. In this case, the film-forming composition is photocurable.

Components that can be included in the film-forming composition are described below. The components described below are basically known in the technical field of paints and the like.

- Resin The composition for film formation can contain resin.
Examples of resins include those known in the field of paints and the like. (Meth)acrylic resins, urethane resins, epoxy resins, polyester resins, alkyd resins, and the like are not particularly limited.

The resin preferably contains a resin having at least one partial structure (hereinafter also referred to as "flexible partial structure") selected from the group consisting of polycaprolactone, polycaprolactam, polycarbonate, polyester and polyether. The flexible partial structure may exist in any of the main chain, side chain, end, and the like of the resin.
By using a resin having a flexible partial structure, self-repairing properties can be imparted to the membrane. In other words, the action of the filler particles not only makes it difficult for scratches to occur, but also makes it possible to repair the scratches even if they do occur, or to make them inconspicuous.

As one aspect, the resin preferably contains a (meth)acrylic resin.
(Meth)acrylic resins are typically copolymers.
The (meth)acrylic resin preferably contains a (meth)acrylate structural unit having a hydroxy group in a side chain for reaction with a curing agent. Examples of this structural unit include structural units derived from hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and hydroxybutyl (meth)acrylate.
The amount of this structural unit is, for example, 1 to 50% by mass, more preferably 2 to 30% by mass, still more preferably 3 to 25% by mass, relative to the entire (meth)acrylic resin.

The (meth)acrylic resin is preferably a monomer represented by CH ₂ =CR-COO-R' (R is a hydrogen atom or a methyl group, R' is a flexible partial structure, that is, polycaprolactone, polycaprolactam, polycarbonate , a group containing at least one partial structure selected from the group consisting of polyesters and polyethers). By including this structural unit in the (meth)acrylic resin, self-repairing properties can be imparted to the film.
The amount of this structural unit is, for example, 1 to 60% by mass, more preferably 2 to 50% by mass, still more preferably 3 to 40% by mass, relative to the entire (meth)acrylic resin.

The (meth)acrylic resin is preferably a monomer represented by the general formula CH ₂ =CR-COO-R'' (R is a hydrogen atom or a methyl group, R'' is an alkyl group, monocyclic or polycyclic cycloalkyl group, aryl group, or aralkyl group).
Examples of this structural unit include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl ( Structural units derived from monomers such as meth)acrylate, n-lauryl (meth)acrylate, n-stearyl (meth)acrylate, phenyl (meth)acrylate, and benzyl (meth)acrylate can be mentioned.
The amount of this structural unit is, for example, 1 to 90% by mass, more preferably 10 to 85% by mass, still more preferably 20 to 80% by mass, relative to the entire (meth)acrylic resin.

The (meth)acrylic resin may contain a structural unit having an amide group.
Examples of structural units having an amide group include structural units derived from monomers such as (meth)acrylamide, more specifically (meth)acrylamide, and N,N-dialkyl(meth)acrylamide. Among these, N,N-dialkyl(meth)acrylamides are preferred.
Structural units having an amide group include structural units derived from monomers such as dimethyl(meth)acrylamide and diethyl(meth)acrylamide.
When the (meth)acrylic resin contains a structural unit having an amide group, the amount thereof is usually 20 to 85% by mass, preferably 30 to 80% by mass, more preferably 30 to 80% by mass, based on the total amount of the (meth)acrylic resin. 40 to 75% by mass.

The (meth)acrylic resin preferably contains a structural unit derived from acrylic acid or methacrylic acid.
The amount of this structural unit is, for example, 0.1 to 30% by mass, more preferably 0.2 to 20% by mass, and still more preferably 0.5 to 10% by mass with respect to the entire (meth)acrylic resin. .

The (meth)acrylic resin may contain a structural unit derived from a monomer that is not a (meth)acrylic monomer and is copolymerizable with the (meth)acrylic monomer. For example, structural units derived from styrene-based monomers such as styrene and α-methylstyrene, vinyl-based monomers such as vinyl acetate and vinyl propionate, and unsaturated carboxylic acid monomers such as itaconic acid, maleic acid and fumaric acid may be included. good.
However, from the viewpoint of flexibility, compatibility with other components, solvent solubility, etc., the amount of structural units derived from monomers other than (meth)acrylic monomers in the (meth)acrylic resin is preferably (meth ) 50% by mass or less, more preferably 20% by mass or less, still more preferably 10% by mass or less, and particularly preferably 0 based on the total acrylic resin.

The (meth)acrylic resin can be obtained by a known polymerization method (for example, radical polymerization method). For specific polymerization methods, see Examples given later.

When the film-forming composition contains a resin, the film-forming composition may contain only one resin, or may contain two or more resins.
When the film-forming composition contains a resin, the amount thereof is, for example, 10 to 80% by mass, preferably 30 to 70% by mass, more preferably 40% by mass, based on the total nonvolatile components in the composition (100% by mass). ~60% by mass.

- Curing agent The film-forming composition can contain a curing agent. Any curing agent can be used as long as it cures the film by, for example, reacting with the resin when the composition is heated. In other words, when the film-forming composition includes a curing agent, the film-forming composition is typically thermosetting.
Preferably, isocyanate compounds (including blocked isocyanate compounds) can be used as curing agents. The isocyanate compound has good curability especially when the resin has a hydroxyl group. In terms of storage stability, blocked isocyanate compounds are more preferred.
The isocyanate compound is preferably a polyfunctional isocyanate. The polyfunctional isocyanate is preferably di- to hexa-functional (ie, has 2-6 reactive isocyanate groups per molecule), more preferably di- to tetra-functional.

When the film-forming composition contains a curing agent, the film-forming composition may contain only one curing agent, or may contain two or more curing agents.
When the film-forming composition contains a curing agent, the content of the curing agent is preferably 5 to 55% by mass, more preferably 10 to 50% by mass, based on the total nonvolatile components of the composition (100% by mass). , more preferably 15 to 45% by mass.

- Polyol The film-forming composition may contain a polyol. The polyol used here does not correspond to the resins described above.
In particular, when an isocyanate compound is used as the curing agent, the combined use of a polyol can increase, for example, the crosslink density of the film. Thereby, the abrasion resistance of the film can be enhanced, the stain resistance of the film can be enhanced, and the mechanical strength of the film can be enhanced.
From the viewpoint of increasing the crosslink density, the polyol is preferably a triol or a tetraol, more preferably a tetraol.

Usable polyols are not particularly limited. For example, polycaprolactone polyol, polycaprolactam polyol, polycarbonate polyol, polyester polyol, polyether polyol and the like can be used. These are preferable in that, due to their flexible molecular skeleton, the film can easily maintain appropriate flexibility while increasing the crosslink density, self-healing properties can be expected, and the like.

In particular, polycaprolactone polyol is preferred as the polyol, and polycaprolactone tetraol is preferred. As the polycaprolactone polyol, for example, a corresponding one from Daicel Co., Ltd.'s product name "PLAXEL" series can be used.

When using a polyol, only one type may be used, or two or more types may be used in combination.
When the composition contains a polyol, its content is preferably 1 to 80% by mass, more preferably 5 to 70% by mass, more preferably 10 to 60% by mass, based on the total nonvolatile components of the composition. % by mass.

-Polymerizable compound The film-forming composition may contain a polymerizable compound. The polymerizable compound can specifically include a cationically polymerizable compound and/or a radically polymerizable compound.

Examples of cationic polymerizable compounds include oxetane compounds, epoxy compounds, vinyl ether compounds, and the like. Here, as specific examples of the epoxy compound, in addition to the above-mentioned epoxy resins, known or commercially available epoxy (meth)acrylates and the like can also be mentioned.
The cationic polymerizable compound is preferably mono- to tetra-functional, more preferably bi- to tetra-functional.

Radically polymerizable compounds include compounds having one or more polymerizable carbon-carbon double bonds in one molecule. The radically polymerizable monomer is preferably a compound having one or more (meth)acrylic structures in one molecule.
Although there is no particular upper limit for the number of polymerizable carbon-carbon double bonds possessed by one molecule of the radically polymerizable compound, it is typically 8 or less, preferably 6 or less.

Urethane (meth)acrylate (a polymer or oligomer having a urethane bond and a (meth)acryloyl group) is also preferred as the radically polymerizable compound. The use of urethane (meth)acrylate tends to facilitate appropriate adjustment of the strength and flexibility of the formed film.

- Photopolymerization initiator The photopolymerization initiator can specifically contain a photocationic polymerization initiator and/or a photoradical polymerization initiator.

Any photocationic polymerization initiator can be used as long as it can generate cations upon irradiation with light and polymerize the polymerizable compound in the composition. For example, onium salts, more specifically known photocationic initiators such as sulfonium salt derivatives and iodonium salt derivatives can be mentioned.

More specific examples of photocationic polymerization initiators include diazonium salts, iodonium salts, sulfonium salts and the like. These have cation moieties of aromatic diazonium, aromatic iodonium or aromatic sulfonium, respectively, and anion moieties of BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , [BX ₄ ] ⁻ (where X is at least two fluorine or a phenyl group substituted with a trifluoromethyl group).
Commercially available photo cationic polymerization initiators include CPI-100P, CPI-200K (manufactured by San-Apro Co., Ltd.), WPI-113, WPI-124 (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) and the like.

The radical photopolymerization initiator is not particularly limited as long as it can generate radicals upon irradiation with light and polymerize the radically polymerizable monomer in the composition.

Specific examples of photoradical polymerization initiators include α-hydroxyketone photoinitiators, α-aminoketone photoinitiators, bisacylphosphine photoinitiators, monoacylphosphine oxides, bisacylphosphine oxides such as 2,4,6 -trimethylbenzoylbiphenylphosphine oxide, ethyl-2,4,6-trimethylbenzoylphenylphosphinate, mono- and bis-acylphosphine photoinitiators, benzyldimethyl-ketal photoinitiators, oligo[2-hydroxy-2-methyl- 1-[4-(1-methylvinyl)phenyl]propanone] and the like.
Examples of commercially available photoradical polymerization initiators include the IRGACURE (registered trademark) series sold by BASF. Of course, other radical photopolymerization initiators can also be used.

When the film-forming composition contains a photopolymerization initiator, the film-forming composition may contain only one type of photopolymerization initiator, or may contain two or more types of photopolymerization initiators.
When the film-forming composition contains a photopolymerization initiator, the amount thereof is usually 0.5 to 15 parts by weight, preferably 1.0 to 10 parts by weight, based on 100 parts by weight of non-volatile components.

- Solvent The film-forming composition may contain a solvent. However, for example, when the film-forming composition is a photocurable composition, the film-forming composition may not contain a solvent.

Solvents are typically organic solvents. Examples of organic solvents include aromatic hydrocarbon solvents such as toluene and xylene, methanol, ethanol, isopropyl alcohol, n-butanol, isobutanol, tert-butanol (2-methyl-2-propanol), tert-amyl alcohol, dye Examples include alcohol solvents such as acetone alcohol, ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, and ester solvents such as ethyl acetate, propyl acetate, butyl acetate and isobutyl acetate.

Alternatively, part or all of the solvent may be water. For example, when a water-soluble or water-dispersible resin (emulsion type, etc.) is used as the resin, part or all of the solvent is preferably water.
However, from the viewpoint of drying speed during film formation, it is preferable that most or all of the solvent is an organic solvent. Specifically, the amount of water in the entire solvent is preferably 10% by mass or less, more preferably 1% by mass or less, and even more preferably 0.5% by mass or less. Particularly preferably, the film-forming composition of the present embodiment does not substantially contain water (excluding water that is unavoidably contained during the manufacturing process or over time).

When a solvent is used, the amount used can be such that the non-volatile component concentration of the composition is, for example, 5 to 99% by mass, preferably 10 to 70% by mass.

• Other components The film-forming resin composition may contain one or more optional components in addition to the above. For example, it may contain a curing accelerator (curing catalyst, etc.), a surfactant, a leveling agent, an ultraviolet absorber, a light stabilizer, a component for enhancing design (for example, a dye such as a pigment), and the like.

The film-forming composition can be produced by mixing and dispersing the components described above. As for the method of mixing and dispersing, a known method can be appropriately applied.
Alternatively, the film-forming composition may be a so-called two-component system. For example, the film-forming composition may be a two-liquid composition containing a curing agent and other components in separate containers.

<Membrane and article with membrane>
A film can be formed using the film-forming composition described above. Also, by forming a film on the surface of an article using the film-forming composition described above, an article having a film can be produced.

Typically, a film-bearing article can be produced by applying the film-forming composition to the surface of the article, drying the solvent, heat curing, and the like.
The application method is not particularly limited, such as spray, brush, and roller. Various coating devices and printing devices may be used.
The temperature and time for thermosetting may be appropriately set within a range in which the base material layer is not deformed. The temperature is, for example, 40 to 120° C., and the time is, for example, 10 minutes to 24 hours. Examples of the heat curing method include a method using hot air and a drying oven (dryer) of a known coating machine.

<Molding resin material and molded product>
A resin material for molding can be obtained by, for example, melt-kneading the above filler particles and a thermoplastic resin. By using this molding resin material and performing so-called thermoforming such as injection molding or extrusion molding, it is possible to produce a molded article having good scratch resistance, for example.
It is thought that filler particles tend to be unevenly distributed on the surface when a molding resin material is melted and injected into a mold.

Examples of thermoplastic resins include polyolefins such as polyethylene and polypropylene, polyesters such as polyamides, polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polyether esters, polyphenylene ethers, polyacetals, polymethyl methacrylates, polystyrene, and polycarbonates. be able to.
The resin material for molding may contain only one type of thermoplastic resin, or may contain two or more types thereof.

The content of filler particles in the molding resin material is preferably 0.5 to 20% by mass, more preferably 1 to 10% by mass, based on the entire molding resin material. When the content is 0.5% by mass or more, the effects (for example, scratch resistance) of using the filler particles can be sufficiently obtained. When the content is 20% by mass or less, the amount of the thermoplastic resin can be made sufficient. This is preferable in terms of the strength and durability of the molded product, ease of molding, and the like.

Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than those described above can be adopted. Moreover, the present invention is not limited to the above-described embodiments, and includes modifications, improvements, etc. within the scope of achieving the object of the present invention.
Examples of reference forms are added below.
1.
modified with a group containing a structure represented by the above general formula (1),
Filler particles whose primary particles have an average particle size of 0.4 to 3 μm based on electron microscopic observation.
In general formula (1),
Two R are each independently a hydrogen atom, a monovalent organic group or a group represented by the above general formula (2), and at least one of the two R is a group represented by the above general formula (2 ) is a group represented by
L is a divalent linking group,
* is a linker with other chemical structures.
In general formula (2),
R ¹ is a group containing a linear or branched alkyl group having 4 or more carbon atoms, a silicon atom-containing group or a fluorine atom-containing group,
R2 is a hydrogen atom or a methyl group ^.
2.
1. The filler particles according to
Filler particles having a ratio of primary particles having a particle size of 0.4 μm or less on a number basis of 10% or less.
3.
1. or 2. The filler particles according to
Filler particles in which the proportion of primary particles having a particle size of 2.8 μm or more on a number basis is 20% or less.
4.
1. ~3. The filler particles according to any one of
Filler particles, wherein the inorganic particles are modified with a group containing a structure represented by general formula (1).
5.
4. The filler particles according to
Filler particles whose inorganic particles are at least one selected from the group consisting of aluminosilicate particles, alumina particles and silica particles.
6.
1. ~ 5. The filler particles according to any one of
Filler particles wherein R ¹ in the general formula (2) is a group containing a branched alkyl group.
7.
1. ~ 5. The filler particles according to any one of
Filler particles in which R ¹ in general formula (2) is a group containing a polydimethylsiloxane structure.
8.
1. ~7. A film-forming composition comprising the filler particles according to any one of .
9.
8. The film-forming composition according to
A film-forming composition comprising a polymerizable compound and a photopolymerization initiator.
10.
8. The film-forming composition according to
A film-forming composition comprising a resin having at least one partial structure selected from the group consisting of polycaprolactone, polycaprolactam, polycarbonate, polyester and polyether.
11.
8. ~ 10. The film-forming composition according to any one of
A film-forming composition having a filler particle content of 0.5 to 10% by mass in the total non-volatile components.
12.
8. ~ 11. An article provided with a film formed using the film-forming composition according to any one of .
13.
1. ~7. and a thermoplastic resin.
14.
13. A molded product formed using a molding resin material.

Embodiments of the present invention will be described in detail based on examples and comparative examples. In addition, the present invention is not limited to the examples.

<Production of filler particles>
[Example 1: Surface modified particles 1]
First, the following components were mixed and reacted by stirring at 70° C. for 16 hours.
・ 3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-903) (hereinafter referred to as “3-APTMS”) 21.6 parts by mass ・ Isostearyl acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., NK Ester S-1800A) (hereinafter referred to as "ISA") 78.4 parts by mass (molar ratio ... 3-APTMS: ISA = 1: 2)

The disappearance of the double bond in ISA was confirmed by infrared absorption spectrometry, and the reaction was terminated to obtain a reaction product of 3-APTMS and ISA (hereinafter referred to as compound 1).

Next, the following were mixed and heated and stirred at 80° C. for 30 minutes to modify the surface of the raw material particles of sodium aluminosilicate spherical particles.
- Spherical particles of sodium aluminosilicate (Shilton AMT08L, manufactured by Mizusawa Chemical Industry Co., Ltd., volume average particle diameter 0.9 μm measured by Coulter counter method) 20 parts by weight - Compound 1 obtained above 1 part by weight - Heptane 30 Parts by mass Dibutyl tin dilaurate (TN-12, manufactured by Sakai Chemical Industry Co., Ltd.) 0.05 parts by mass

After heating and stirring, heptane was distilled off at 120°C.
As described above, particles surface-treated with compound 1 and modified with groups (including an isostearyl group, which is a specific alkyl group) having a structure represented by general formula (1) were obtained.
This particle is referred to as surface-modified particle 1 .

[Example 2: Surface modified particles 2]
In the same manner as in Example 1, except that Shilton AMT25 (manufactured by Mizusawa Chemical Industry Co., Ltd., volume average particle size 2.5 μm measured by the Coulter counter method) was used instead of Shilton AMT08L, general formula (1) Particles modified with a group containing a structure represented by (including an isostearyl group, which is a specific alkyl group) were obtained.
These particles are referred to as surface-modified particles 2 .

[Example 3: Surface modified particles 3]
(1) Synthesis of a compound having an acryloyl group and a group containing a polydimethylsiloxane structure In a four-necked flask equipped with a stirrer, thermometer, condenser and nitrogen gas inlet tube, 100 parts by mass of toluene and a methacryloyl group were added. 40 parts by mass of polydimethylsiloxane macromonomer (FM0721 manufactured by JNC Corporation, molecular weight of about 5000) was charged. Then, the mixture was heated to 110° C. under a nitrogen atmosphere while stirring.
A mixture consisting of the following components was added dropwise to this four-necked flask over 2 hours.
・Methyl methacrylate 40 parts by mass ・Isocyanate ethyl methacrylate (manufactured by Showa Denko Co., Ltd., Karenz MOI) 20 parts by mass ・2,2-azobis-2-methylbutyronitrile (polymerization initiator, manufactured by Wako Pure Chemical Industries, Ltd., V- 59) 5 parts by mass After completion of dropping, the mixture was heated and stirred at the same temperature for 5 hours to synthesize a (meth)acrylic resin, thereby obtaining a composition containing the (meth)acrylic resin.

A mixture of the following components was added to the above composition and heated to 70° C. with stirring under a nitrogen atmosphere. Then, the mixture was heated and stirred at the same temperature for 3 hours.
・Toluene 80 parts by mass ・Hydroxy group-containing polyfunctional acrylate compound (Aronix M305 manufactured by Toagosei Co., Ltd., containing pentaerythritol triacrylate) (hereinafter referred to as “PETA”) 80 parts by mass ・Dibutyltin dilaurate 0.03 parts by mass ・0.2 parts by mass of hydroquinone monomethyl ether

The isocyanate groups in the (meth)acrylic resin were reacted with the hydroxy groups in PETA by the heating and stirring. As a result, a composition (hereinafter referred to as "intermediate composition") containing "a compound having an acryloyl group and a group containing a polydimethylsiloxane structure" was obtained. The solid content concentration of this composition was adjusted to 50% by mass.

(2) Modification of Particle Surface First, the following components were mixed and heated with stirring at 80° C. for 30 minutes. This caused the Shiltone AMT08L and 3-APTMS to react.
・Silton AMT08L 40 parts by mass ・3-APTMS 1 part by mass ・Toluene 58 parts by mass ・Acetic acid 1 part by mass

After that, 5 parts by mass of the intermediate composition obtained in (1) above (2.5 parts by mass in terms of solid content) was additionally added, and the mixture was heated and stirred at 80° C. for 2 hours. Then, by distilling off the solvent, particles modified with a group containing a structure represented by general formula (1) (including a polydimethylsiloxane structure) were obtained.
These particles are referred to as surface-modified particles 3 .

[Example 4: Surface modified particles 4]
Particles modified with a group containing a structure represented by general formula (1) were obtained in the same manner as in Example 3, except that Shiltone AMT25 was used instead of Shiltone AMT08L.
These particles are referred to as surface modified particles 4 .

[Example 5: Surface modified particles 5]
First, the following components were mixed and heated with stirring at 80° C. for 30 minutes. This allowed the siltone AMT25 and 3-APTMS to react.
・Silton AMT25 40 parts by mass ・3-APTMS 1 part by mass ・Toluene 58 parts by mass ・Acetic acid 1 part by mass

After that, 10 parts by mass (3 parts by mass as an active ingredient) of acryloyl group-containing fluororesin (manufactured by DIC Corporation, Megafac RS-72-K, 30% by mass of active ingredient) was added, and further at 80 ° C. for 2 hours. It was heated and stirred. Then, by distilling off the solvent, particles modified with a group (including a fluorine atom-containing group) having a structure represented by general formula (1) were obtained.
These particles are referred to as surface-modified particles 5 .

[Example 6: Surface modified particles 6]
First, the following components were mixed and reacted by stirring at 70° C. for 16 hours.
・ 21.6 parts by mass of 3-APTMS ・ Mixed with 34.3 parts by mass of isoamyl acrylate (light acrylate IAA manufactured by Kyoeisha Chemical Co., Ltd.) (hereinafter referred to as “IAA”) (molar ratio 3-APTMS: IAA=1:2)

By infrared absorption spectroscopy, it was confirmed that the double bond in IAA had disappeared, and the reaction was terminated to obtain a reaction product of 3-APTMS and IAA (hereinafter referred to as compound 2).

Next, the following were mixed and heated and stirred at 80° C. for 30 minutes to modify the surface of Shilton AMT25.
・Silton AMT25 20 parts by mass ・Compound 2 obtained above 1 part by mass ・Heptane 30 parts by mass ・Dibutyltin dilaurate (manufactured by Sakai Chemical Industry Co., Ltd., TN-12) 0.05 parts by mass

After heating and stirring, heptane was distilled off at 120°C.
As a result, particles surface-treated with compound 2 and modified with groups (including an isoamyl group, which is a specific alkyl group) having a structure represented by general formula (1) were obtained.
These particles are referred to as surface modified particles 6 .

<Measurement of particle size>
The average particle diameter of the primary particles, the ratio of primary particles having a particle size of 0.4 μm or less, and the ratio of primary particles having a particle size of 2.8 μm or more of the obtained surface-modified particles 1 to 6 were determined as follows. .
(1) The particles were diluted with methyl ethyl ketone to a concentration of about 1% by mass, and subjected to dispersion treatment for 1 minute using an ultrasonic cleaner (manufactured by AS ONE Corporation, ASU-6) to obtain a dispersion liquid.
(2) The dispersion liquid was dropped onto a sample stage (manufactured by Nissin EM Co., Ltd., SEM sample stage AB made of brass), and the methyl ethyl ketone was dried under normal temperature and normal pressure.
(3) The particles dried above were sputtered and coated with gold of about 10 nm to prepare a sample for SEM (scanning electron microscope) observation.
(4) Using an SEM (scanning electron microscope), the observation sample was photographed at an accelerating voltage of 25 kV.
(5) Out of the photographed images, 100 particles judged to be primary particles (particles that are not agglomerated) were measured for equivalent perfect circle diameters.
(6) Based on the numerical data obtained in (5), the average particle size of primary particles, the ratio of primary particles with a particle size of 0.4 μm or less, and the ratio of primary particles with a particle size of 2.8 μm or more (number basis) asked.

The structure of the atomic groups modifying the particles and the measurement results of the particle diameter are summarized below.

<Production of film-forming composition>
[Production of light (ultraviolet) curable film-forming composition: Examples 1 to 7, Comparative Examples 1 to 3]
First, the following components were put into a flask equipped with a stirrer, a thermometer and a condenser, the temperature was raised to 60° C., and the reaction was carried out by heating and stirring at the same temperature for 3 hours. As a result, a composition containing a urethane (meth)acrylate compound (solid content: 50% by mass) was obtained.
・Toluene 145 parts by mass ・Isocyanate compound (manufactured by Asahi Kasei Corporation, TPA-100, isocyanurate type of hexamethylene diisocyanate, isocyanate group content 23% by mass, solid content 100% by mass) 50 parts by mass ・Polycaprolactone-modified hydroxyethyl acrylate (Plaxel FA2, manufactured by Daicel Corporation) 95 parts by mass Dibutyl tin dilaurate 0.02 parts by mass Hydroquinone monomethyl ether 0.2 parts by mass

Next, the following components were mixed, and butyl acetate was added to adjust the solid content concentration to obtain a photocurable composition having a solid content of 50% by mass.
- Composition obtained above (solid content: 50% by mass) 400 parts by mass (200 parts by mass as solid content)
・"Intermediate composition" obtained when producing surface-modified particles 3 (solid content: 50% by mass) 200 parts by mass ・Mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate 400 parts by mass ・Photopolymerization initiator ( BASF Corporation, Irgacure 184) 50 parts by mass

For 100 parts by mass of the solid content of the photocurable composition obtained above (250 parts by mass including the solvent), as filler particles, the above surface-modified particles 1 to 5 or comparative particles (not surface-treated ) was added in the amount (parts by mass) shown in Table 2 or 3 below. Then, using a disper, the mixture was stirred at room temperature (25° C.) for 1 hour.
As described above, a photocurable film-forming composition was obtained.

[Production of Thermosetting Film-Forming Compositions: Examples 8-11, Comparative Examples 4 and 5]
First, 100 parts by mass of methyl isobutyl ketone was charged into a flask equipped with a stirrer, a thermometer, a condenser and a nitrogen gas inlet tube, and the temperature was raised to 110°C.

Separately from the above, a monomer mixture was prepared by mixing the following components.
・Methyl methacrylate (MMA) 49 parts by mass ・n-Butyl methacrylate (BMA) 30 parts by mass ・Polycaprolactone-modified hydroxyethyl acrylate (PLAXEL FA2D manufactured by Daicel Co., Ltd.) 5 parts by mass ・2-Hydroxyethyl methacrylate (HEMA) 15 parts by mass・Methacrylic acid (MAA) 1 part by mass ・1,1′-Azobis (cyclohexane-1-carbonitrile) (manufactured by Wako Pure Chemical Industries, Ltd., V-40) 3 parts by mass

The monomer mixture was dropped into the flask over 2 hours and allowed to react for 5 hours. Remove from heat, cool to room temperature, and dilute with methyl isobutyl ketone. As a result, a resin solution containing 40% by mass of (meth)acrylic resin was obtained.

Polycaprolactone tetraol (manufactured by Daicel Corporation, Plaxel 410D, molecular weight 1000, hydroxyl value 216 to 232 mgKOH/g) is mixed with 50 parts by mass of the above resin solution (including 100 parts by mass of the (meth)acrylic resin) of 250 parts by mass. bottom. This was used as a main component solution (solid content: 50% by mass).

To 200 parts by mass of the main agent solution (100 parts by mass as a solid content), as filler particles, the above surface-modified particles 2, 4, 5, and 6 or particles for comparison (AMT25 that is not surface-treated) are added. The amount (parts by mass) described in Table 2 or 3 was added. Then, using a disper, the mixture was stirred at room temperature (25° C.) for 1 hour.
After that, 20 parts by mass of an isocyanate compound (TPA-100, hexamethylene diisocyanate isocyanurate type, isocyanate group content 23% by mass, solid content 100% by mass, manufactured by Asahi Kasei Corporation) was added and mixed.
Then, butyl acetate was added to adjust the solid content concentration to 30% by mass.
As described above, a thermosetting film-forming composition was obtained.

<Preparation of film (cured film)>
[Preparation of Film Using Photocurable Film-Forming Composition]
A photocurable film-forming composition was air-sprayed onto a colorless (transparent) and black polycarbonate plate (manufactured by TP Giken Co., Ltd., a square with a thickness of 1.0 mm and a side length of 100 mm x 100 mm). painted with
After that, the film was dried at 80°C for 5 minutes to remove the solvent, and then irradiated with ultraviolet rays using a high-pressure mercury lamp (manufactured by Eyegraphic Co., Ltd.) under the conditions of an integrated light quantity of 800 mJ/cm ² .
As described above, two types of polycarbonate plates (hereinafter referred to as test plates) each having a cured film having a thickness of 15 μm were obtained.

[Preparation of Film Using Thermosetting Film-Forming Composition]
A thermosetting film-forming composition was applied to each of colorless (transparent) and black polycarbonate plates (manufactured by TP Giken Co., Ltd., thickness 1.0 mm, side length 100 mm x 100 mm square) with an air spray. bottom.
After that, it was heated at 80° C. for 60 minutes and allowed to stand at normal temperature (25° C.) for 24 hours.
As described above, two types of polycarbonate plates (hereinafter referred to as test plates) each having a cured film having a thickness of 15 μm were obtained.

<Evaluation>
[Scratch resistance]
Using an eraser tester (manufactured by Sony Corporation), steel wool #0000 (Bonstar Steel Wool Pound Roll, B-204, manufactured by Bonstar Sales Co., Ltd.) is brought into contact with a test plate in which a film is formed on a black polycarbonate plate. and the steel wool was reciprocated under the conditions shown below.
- Examples 1 to 7, Comparative Examples 1 to 3 (film formation with photocurable film forming composition): 1 kg load, 300 reciprocations, stroke 20 mm
- Examples 8 to 11, Comparative Examples 4 and 5 (film formation with thermosetting film-forming composition): 500 g load, 100 reciprocations, stroke 20 mm

The 60° gloss value was measured on the test panel before and after the test using a BYK-Gardner GmbH glossmeter (Micro-Gloss). Then, the gloss retention rate was calculated by the following (Equation 1). A high gloss retention rate means that the cured film is less likely to be scratched.

[Haze value]
A haze meter (TC-H3DPK/2, manufactured by Tokyo Denshoku Co., Ltd.) was used to measure the haze of a test plate obtained by forming a film on a colorless (transparent) polycarbonate plate.

Tables 2 and 3 show the compositions of the film-forming compositions and the evaluation results. The numbers in the column of "film-forming composition" in the table represent the amount of each component (parts by mass in terms of solid content).

As shown in Tables 2 and 3, in the film formation using the photocurable film-forming composition, it is better to use surface-modified particles 1 to 6 as filler particles than to use filler particles that have not been surface-treated. There was a tendency for the gloss retention (scratch resistance) to be better than in the case where no filler particles were used. (See Examples 1-5 and Comparative Examples 1-3. The amount of filler particles used is the same in these examples.)
From another point of view, it was found that by using surface-modified particles as filler particles, good gloss retention (scratch resistance) can be obtained with a smaller amount of particles (especially see Examples 6 and 7). sea bream).

Also in film formation using a thermosetting film-forming composition, the use of surface modified particles as filler particles has a higher gloss retention rate (scratch resistance) than the use of untreated filler particles. tended to be good. (See Examples 8-11 and Comparative Examples 4 and 5.)

From a viewpoint different from gloss retention (scratch resistance), the "haze" value in each example was sufficiently small. That is, it can be said that the film-forming compositions of Examples 1 to 11 are also suitable for use as clear paints.

<Observation of Uneven Distribution of Particles>
In order to directly confirm that the surface-modified particles are less likely to settle, observation of the film surface with a laser microscope and elemental analysis of the film surface with EDS (energy dispersive X-ray spectroscopy) were performed. Specifically, it went as follows.

First, a film-forming composition was prepared in the same manner as in Example 9, except that the concentration of the surface-modified particles 4 in the total solid content was 5% by mass. For comparison, a film-forming composition was prepared in the same manner as in Comparative Example 5 except that the concentration of AMT25 in the total solid content was 5% by mass.
Each of these film-forming compositions was formed into a cured film as described in the above [Preparation of film using thermosetting film-forming composition].

The unevenness of the surface of the obtained cured film was visualized using a laser microscope (OLS-4100, manufactured by Olympus Corporation). The visualized results are shown in FIG. In FIG. 1, the protruding parts of the surface (parts where the particles are thought to be exposed on the film surface) are shown in bright colors.

Moreover, the distribution state of Al and Si on the surface of the obtained cured film was visualized. Specifically, using an analytical scanning electron microscope (manufactured by JEOL Ltd., JSM-6380LA), visualization was performed by observing backscattered electron images under the condition of an accelerating voltage of 15 kV. FIG. 2 shows the visualized results. In FIG. 2, portions where Al and/or Si are present (ie, portions where aluminosilicate particles are present) are shown in bright colors.

From FIGS. 1 and 2, it was confirmed that the surface-modified particles 4 tended to be less prone to sedimentation during film formation than the non-surface-treated particles.

Claims (12)

modified with a group containing a structure represented by the following general formula (1),
The average particle size of the primary particles based on electron microscope observation is 0.4 to 3 μm,
Filler particles having a ratio of primary particles having a particle size of 0.4 μm or less on a number basis of 10% or less ,
In the filler particles, at least one inorganic particle selected from the group consisting of aluminosilicate particles, alumina particles and silica particles is modified with a group containing a structure represented by the general formula (1). filler particles .

In general formula (1),
Two R are, independently of each other, a hydrogen atom, a monovalent organic group or a group represented by the following general formula (2), and at least one of the two R is represented by the following general formula (2) is a group represented by
L is a divalent linking group,
* is a linker with other chemical structures.

In general formula (2),
R ¹ is a group containing a linear or branched alkyl group having 4 or more carbon atoms, a silicon atom-containing group or a fluorine atom-containing group,
^R2 is a hydrogen atom or a methyl group. modified with a group containing a structure represented by the following general formula (1),
Filler particles having an average primary particle diameter of 0.4 to 3 μm based on electron microscopic observation,
In the filler particles, at least one inorganic particle selected from the group consisting of aluminosilicate particles, alumina particles and silica particles is modified with a group containing a structure represented by the general formula (1). filler particles.

In general formula (1),
Two R are each independently a hydrogen atom, a monovalent organic group or a group represented by the following general formula (2), and at least one of the two R is the following general formula (2) is a group represented by
L is a divalent linking group,
* is a linker with other chemical structures.

In general formula (2),
R. ¹ is a linear or branched alkyl group having 4 or more carbon atoms, a silicon atom-containing group or a fluorine atom-containing group,
R. ² is a hydrogen atom or a methyl group. The filler particles according to claim 1 or 2,
Filler particles in which the proportion of primary particles having a particle size of 2.8 μm or more on a number basis is 20% or less. The filler particles according to claim 1 ,
Filler particles wherein R ¹ in the general formula (2) is a group containing a branched alkyl group. The filler particles according to any one of claims 1 to 3 ,
Filler particles in which R ¹ in general formula (2) is a group containing a polydimethylsiloxane structure. A film-forming composition comprising the filler particles according to any one of claims 1 to 5 . The film-forming composition according to claim 6 ,
A film-forming composition comprising a polymerizable compound and a photopolymerization initiator. The film-forming composition according to claim 6 ,
A film-forming composition comprising a resin having at least one partial structure selected from the group consisting of polycaprolactone, polycaprolactam, polycarbonate, polyester and polyether. The film-forming composition according to any one of claims 6 to 8 ,
A composition for film formation, wherein the content of the filler particles in the total non-volatile components is 0.5 to 10% by mass. An article provided with a film formed using the film-forming composition according to any one of claims 6 to 9 . A molding resin material comprising the filler particles according to any one of claims 1 to 5 and a thermoplastic resin. A molded article formed using the molding resin material according to claim 11 .

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