阅读说明：本技术 表面保护树脂部件添加用的树脂粒子以及表面保护树脂部件 (Resin particle for adding surface-protecting resin member and surface-protecting resin member ) 是由 稻叶义弘 吉泽久江 于 2019-03-06 设计创作，主要内容包括：本发明涉及表面保护树脂部件添加用的树脂粒子以及表面保护树脂部件。本发明提供一种表面保护树脂部件添加用的树脂粒子,其包含丙烯酸氨基甲酸酯树脂作为主成分,在23℃的马氏硬度为0.5N/mm<Sup>2</Sup>以上220N/mm<Sup>2</Sup>以下,在23℃的恢复率为70％以上100％以下,体积平均粒径D50v为3μm以上50μm以下。(The present invention relates to resin particles for adding a surface-protecting resin member and a surface-protecting resin member. The present invention provides a resin particle for adding a surface-protecting resin member, which contains an acrylic urethane resin as a main component and has a Martensitic hardness of 0.5N/mm at 23 DEG C 2 Above 220N/mm 2 The recovery rate at 23 ℃ is 70-100%, and the volume average particle diameter D50v is 3-50 μmThe following steps.)

1. Resin particles for adding a surface-protecting resin member, which contain an acrylic urethane resin as a main component and have a Martensitic hardness at 23 ℃ of 0.5N/mm²Above 220N/mm²The recovery rate at 23 ℃ is 70-100%, and the volume average particle diameter D50v is 3-50 μm.

2. The resin particle for adding a surface-protecting resin member as claimed in claim 1, wherein the volume particle size distribution index GSDv is from 1.0 to 1.5,

wherein GSDv is (D84v/D16v)^1/2。

3. The resin particle for adding a surface-protecting resin member as claimed in claim 1 or 2, wherein the average circularity is from 0.8 to 1.0.

4. The resin particles for adding a surface protective resin member according to any one of claims 1 to 3, wherein the urethane acrylate resin is a reaction product of a hydroxyl group-containing acrylic resin (a), a polyol (b) and a polyfunctional isocyanate (c), the polyol (b) having 2 or more hydroxyl groups, and the hydroxyl groups being separated by a carbon chain having 6 or more carbon atoms.

5. The resin particles for adding a surface-protecting resin member as claimed in claim 4, wherein the hydroxyl value [ OH ] of the hydroxyl group-containing acrylic resin (a)_A]Hydroxyl value [ OH ] with the above polyol (b)_B]Ratio of [ OH ]_A/OH_B]Is 0.1 to 3 inclusive.

6. The resin particles for adding a surface-protecting resin member according to claim 4 or 5, wherein the hydroxyl-containing acrylic resin (a) is an acrylic resin having a molar ratio of a side-chain hydroxyl group having a hydroxyl group and having 10 or more carbon atoms to a side-chain hydroxyl group having a hydroxyl group and having less than 10 carbon atoms of less than 1/3, including the case where the side-chain hydroxyl group having 10 or more carbon atoms is not present.

7. The resin particles for adding a surface-protecting resin member as claimed in any one of claims 4 to 6, wherein said hydroxyl group-containing acrylic resin (a) is an acrylic resin having a fluorine atom.

8. The resin particle for adding a surface-protecting resin member as claimed in any one of claims 1 to 7, which contains a colorant.

9. A surface protective resin member comprising:

a resin; and

resin particles for adding the surface-protecting resin member according to any one of claims 1 to 8 dispersed in the resin.

10. The surface-protecting resin member as claimed in claim 9, which has a Madin hardness of 0.5N/mm at 23 ℃²Above 220N/mm²The recovery rate at 23 ℃ is 70% to 100%.

11. A surface protective resin member comprising:

a resin; and

resin particles dispersed in the resin, the volume average particle diameter D50v being 3 to 50 [ mu ] m, and the amount of the resin particles added being 5 to 50 vol% based on the entire surface-protecting resin member,

the surface-protecting resin member had a Martensitic hardness at 23 ℃ of 0.5N/mm²Above 220N/mm²The recovery rate at 23 ℃ is 70% to 100%.

12. The surface-protecting resin member as claimed in any one of claims 9 to 11, wherein the surface roughness Ra is 0.2 μm or more and 10 μm or less.

13. The surface-protecting resin member as claimed in any one of claims 9 to 12, which is a resin film having an average thickness of 5 μm or more and 100 μm or less.

Technical Field

The present invention relates to resin particles for adding a surface-protecting resin member and a surface-protecting resin member.

Background

Conventionally, in various fields, a surface protective resin member such as a surface protective film has been provided in order to suppress surface scratches. When the surface protective resin member is provided on an interior material, furniture, leather, or the like, for example, in view of the requirement for a high-grade feeling, it is sometimes required to reduce the gloss of the surface, and particles such as a matting agent may be added to the surface protective resin member.

For example, Japanese patent application laid-open No. 4-82736 discloses a matte-like sheet having a base sheet with a wet index of 38 to 60dyne/cm and a coating film of a matte paint prepared by adding a bead pigment and/or synthetic resin beads to a carrier of a two-pack type curable resin.

Further, Japanese patent application laid-open No. 5-302062 discloses "a coating resin composition for aesthetic adhesive application containing polyurethane polyurea particles having a three-dimensional crosslinked structure and a binder resin as an essential film-forming component".

Further, japanese patent application laid-open No. 5-254072 discloses "a mat-colored resin sheet having a coating film of a urethane resin containing amino acid resin particles formed on a colored resin sheet and having a smooth surface texture".

Further, japanese patent application laid-open No. 2-64166 discloses "a matte coating material having a powder as a component and having a surface of an object to be coated in a matte state by forming irregularities of a coating film from the powder, wherein a polyurethane resin is contained in the coating material in a proportion of 1 to 20 times by weight relative to the powder".

Further, Japanese patent application laid-open No. 8-209029 discloses "a gloss-reducing agent for paint comprising spherical silica or silicate particles, wherein the weight ratio of the gloss-reducing agent to the silica or silicate particles is expressed as SiO₂: MO is 100: 0 to 50: 50 (wherein M represents a metal of group II of the periodic Table of the elements) is amorphous or fine lamellar crystalline in X-ray diffractometry, each particle is independently in a clear spherical shape, and the major axis (D) of the particle is_L) And minor axis (D)_S) Ratio of (D)_S/D_L) Particles having a positive sphericity of 0.8 to 1.0 of 80% or more, represented by the formula (1) (D)₂₅/D₇₅) (in the formula, D₂₅A particle diameter representing a 25% value of a cumulative particle size distribution curve based on a volume basis of a Coulter counter method,D₇₅particle diameter representing 75% value thereof) of 1.2 to 2.0 and a BET specific surface area of 30 to 800m²/g”。

Further, Japanese patent application laid-open No. 9-157545 discloses "a paint gloss remover comprising an aggregate having an oil absorption of less than 80ml/100g and a size of less than 100 μm, and hydrophobic silica".

Further, japanese patent application laid-open No. 5-132636 discloses "a method for forming a coating film, in which, when a coating agent is applied to form a coating film, a coating agent containing crosslinked elastic resin fine particles as an essential component of a film-forming resin is applied, and dried or cured to be hard, thereby forming a flexible coating film".

Further, Japanese patent laid-open No. 2007-262248 discloses "an aqueous matte coating agent comprising 100 parts by weight of a solid content of an aqueous polyurethane resin and 50 to 300 parts by weight of crosslinked, spherical organic resin fine particles".

Disclosure of Invention

The surface-protecting resin member for protection provided on the surface of the base material is required to have scratch resistance (self-repairability in which, for example, even if damage occurs, the damage can be repaired). On the other hand, particles such as a delustering agent may be added to the surface-protecting resin member, and when such particles are added, the scratch resistance may be reduced, and there is a demand for particles in which the reduction of the scratch resistance is suppressed even when the particles are added to the surface-protecting resin member.

The invention aims to provide a resin particle for adding a surface protection resin component, and the resin particle satisfies that the Martensitic hardness at 23 ℃ is more than 220N/mm²In this requirement, when the resin particles provided by the present invention are added to a surface-protecting resin member, the surface-protecting resin member having excellent scratch resistance can be formed, as compared with the resin particles having at least one of the requirements that the recovery rate at 23 ℃ is less than 70%.

According to the 1 st aspect of the present invention, there is provided a resin particle for adding a surface protective resin member, comprising propyleneAcid urethane resin as a main component, having a Martensitic hardness at 23 ℃ of 0.5N/mm²Above 220N/mm²The recovery rate at 23 ℃ is 70-100%, and the volume average particle diameter D50v is 3-50 μm.

According to the invention of claim 2, the volume particle size distribution index GSDv [ (D84v/D16v) of the resin particles for adding the surface protective resin member^1/2]Is 1.0 to 1.5 inclusive.

According to the 3 rd aspect of the present invention, the average circularity of the resin particles for adding the surface-protecting resin member is 0.8 to 1.0.

According to the 4 th aspect of the present invention, the acrylic urethane resin is a reaction product of a hydroxyl group-containing acrylic resin (a), a polyol (b) having 2 or more hydroxyl groups and having a carbon chain of 6 or more carbon atoms separating the hydroxyl groups, and a polyfunctional isocyanate (c).

According to claim 5 of the present invention, the hydroxyl value [ OH ] of the above hydroxyl group-containing acrylic resin (a)_A]Hydroxyl value [ OH ] with the above polyol (b)_B]Ratio of [ OH ]_A/OH_B]0.1 to 3.

According to the 6 th aspect of the present invention, the hydroxyl group-containing acrylic resin (a) is an acrylic resin having a content ratio (molar ratio) of a side chain hydroxyl group having a hydroxyl group and having 10 or more carbon atoms to a side chain hydroxyl group having a hydroxyl group and having less than 10 carbon atoms of less than 1/3 (including the case where the side chain hydroxyl group having 10 or more carbon atoms is not present).

According to the 7 th aspect of the present invention, the above hydroxyl group-containing acrylic resin (a) is an acrylic resin having a fluorine atom.

According to the 8 th aspect of the present invention, the resin particles for adding a surface-protecting resin member contain a colorant.

According to the 9 th aspect of the present invention, there is provided a surface-protecting resin member comprising a resin and resin particles for adding the surface-protecting resin member dispersed in the resin.

According to the 10 th aspect of the present invention, the surface-protecting resin member is a resin member having a Marek's modulus at 23 ℃The hardness is 0.5N/mm²Above 220N/mm²The recovery rate at 23 ℃ is 70% to 100%.

According to the 11 th aspect of the present invention, there is provided a surface-protecting resin member comprising a resin and resin particles dispersed in the resin, wherein the volume average particle diameter D50v is 3 μm or more and 50 μm or less, and the amount of the resin particles added is 5 vol% or more and 50 vol% or less with respect to the entire surface-protecting resin member; the surface-protecting resin member had a Martensitic hardness at 23 ℃ of 0.5N/mm²Above 220N/mm²The recovery rate at 23 ℃ is 70% to 100%.

According to the 12 th aspect of the present invention, the surface protection resin member has a surface roughness Ra of 0.2 μm or more and 10 μm or less.

According to the 13 th aspect of the present invention, the surface protective resin member is a resin film having an average thickness of 5 μm or more and 100 μm or less.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the above aspect 1, 4 or 8, there is provided a resin particle for adding a surface-protecting resin member, which has a Martensitic hardness at 23 ℃ of more than 220N/mm²When the resin particles provided by the above aspect are added to a surface-protecting resin member, a surface-protecting resin member having superior scratch resistance can be formed, as compared to resin particles having at least one of the requirements that the recovery rate at 23 ℃ is less than 70%.

According to the above aspect 2, the resin particles for adding a surface protective resin member, which are excellent in matting performance, can be provided as compared with the case where the volume particle size distribution index GSDv is larger than 1.5.

According to the above aspect 3, the resin particles for adding a surface-protecting resin member having excellent matte properties can be provided as compared with the case where the average circularity is less than 0.8.

According to the above aspect 5, the hydroxyl value [ OH ] of the hydroxyl group-containing acrylic resin (a)_A]And the hydroxyl value [ OH ] of the polyol (b)_B]Ratio of [ OH ]_A/OH_B]When added to a surface-protecting resin member, the resin composition can be provided that can be formed in comparison with the case of less than 0.1Resin particles for adding a surface-protecting resin member, which have excellent scratch resistance.

According to the above aspect 6, as compared with the case where the hydroxyl group-containing acrylic resin (a) is an acrylic resin having a content ratio (molar ratio) of a side chain hydroxyl group having a hydroxyl group and having 10 or more carbon atoms to a side chain hydroxyl group having a hydroxyl group and having less than 10 carbon atoms of 1/3 or more, when added to the surface-protecting resin member, resin particles for surface-protecting-resin-member addition capable of forming a surface-protecting resin member having excellent scratch resistance can be provided.

According to the above aspect 7, the adhesion between particles is reduced as compared with the case where the hydroxyl group-containing acrylic resin (a) is an acrylic resin having no fluorine atom, and therefore, it is possible to provide resin particles for adding a surface protective resin member, which can be easily made smaller in diameter.

According to the above-mentioned item 9, the hardness in March's at 23 ℃ is more than 220N/mm²This requirement can provide a surface-protecting resin member having excellent scratch resistance as compared with the case of resin particles having at least one of the requirements that the recovery rate at 23 ℃ is less than 70%.

According to the above aspect 10, the hardness at 23 ℃ in Ma's hardness is more than 220N/mm²This requirement can provide a surface-protective resin member having excellent scratch resistance as compared with the case where at least one of the requirements is that the recovery rate at 23 ℃ is less than 70%.

According to the above 11 th aspect, the Martensitic hardness at 23 ℃ is more than 220N/mm²This requirement provides a surface-protecting resin member having excellent scratch resistance even when the resin particles having a volume average particle diameter D50v of 3 to 50 μm are contained in an amount of 5% by volume or more, as compared with at least one of the requirements that the recovery rate at 23 ℃ is less than 70%.

According to the above 12 th aspect, a surface-protecting resin member having a reduced surface glossiness can be provided as compared with the case where the surface roughness Ra is less than 0.2 μm.

According to the above 13 th aspect, a surface-protecting resin member having excellent scratch resistance can be provided as compared with the case where the average thickness is less than 5 μm.

Detailed Description

The following describes embodiments of the present invention. The present embodiment is an example of carrying out the present invention, and the present invention is not limited to the following embodiments.

< resin particles for adding surface-protecting resin Member >

The resin particles for adding a surface-protecting resin member of the present embodiment (hereinafter also simply referred to as "resin particles") contain an acrylic urethane resin as a main component, and have a Martensitic hardness at 23 ℃ of 0.5N/mm²Above 220N/mm²The recovery rate at 23 ℃ is 70-100%, and the volume average particle diameter D50v is 3-50 μm.

Here, the "main component" in the resin particles means a component having the largest content in terms of mass ratio in the resin particles. The content of the urethane acrylate resin in the resin particles is preferably 50% by mass or more, and more preferably 60% by mass or more.

In recent years, surface protective resin members, such as surface protective films, have been used for various articles in order to prevent scratches on the surfaces. In general, surface-protecting resin members often have a high surface gloss, and when they are provided on the surface of interior materials, furniture, leather, and the like, the gloss is required to be reduced. As a method for reducing gloss, for example, a technique of adding particles called a delustering agent to a surface protective resin member is known, and synthetic resin particles, inorganic particles, or the like are used as the delustering agent.

In particular, when particles such as synthetic resin particles and inorganic particles are added to a surface-protecting resin member comprising a continuous phase of a resin having scratch resistance (for example, self-repairability), there is a possibility that the scratch resistance is reduced, and particularly when the content of the particles is 20 mass% or more, the reduction in scratch resistance becomes remarkable. In this regard, it is considered that the proportion of the resin constituting the continuous phase decreases as the addition amount of the particles increases, and an interface is generated between the added particles and the continuous phase of the resin, and the presence of the interface has a large influence on the scratch resistance (for example, self-repairability).

In contrast, the resin particles of the present embodiment have the following configuration: which comprises an acrylic urethane resin as a main component and has a Martensitic hardness at 23 ℃ of 0.5N/mm²Above 220N/mm²The recovery rate at 23 ℃ is 70-100%, and the volume average particle diameter D50v is 3-50 μm. It has been found that, in the case of resin particles having such a constitution, in the case of being added to a surface-protecting resin member, excellent flaw resistance (e.g., self-repairability) is exerted despite the presence of an interface between the resin particles and a resin (resin having flaw resistance) constituting a continuous phase.

The resin particles for adding the surface-protecting resin member of the present embodiment will be described in detail below.

Properties of resin particles

Ma hardness

The resin particles of the present embodiment have a Martensitic hardness of 0.5N/mm at 23 ℃²Above 220N/mm²The following. Preferably 1N/mm²Above 80N/mm²Below, more preferably 1N/mm²Above 5N/mm²The following.

By setting the Martensitic hardness (23 ℃) at 220N/mm²Hereinafter, a surface-protecting resin member having excellent scratch resistance (e.g., self-repairability) can be obtained when added to a surface-protecting resin member. On the other hand, the Martensitic hardness is set to 0.5N/mm²As described above, the resin particles can easily retain the desired shape.

Recovery rate

The resin particles of the present embodiment have a recovery rate at 23 ℃ of 70% to 100%, preferably 80% to 100%, and more preferably 90% to 100%.

The recovery rate is an index indicating the self-repairing property (the property that deformation due to stress recovers within 1 minute after the load of stress is removed, that is, the degree of damage repair) of the resin material. That is, by setting the recovery rate (23 ℃) to 70% or more, the easiness of damage repair (i.e., self-repairability) is improved, and a surface-protecting resin member having excellent damage resistance (e.g., self-repairability) can be obtained when added to the surface-protecting resin member.

For measurement of the mahalanobis hardness and the recovery ratio in the resin particles, Fischer scopehm2000 (manufactured by Fischer corporation) was used as a measurement device, and a sample was fixed to a slide glass with an adhesive and set in the measurement device. The sample was applied with a load of up to 0.5mN for 15 seconds at a specific measurement temperature (e.g., 23 ℃) and held at 0.5mN for 5 seconds. The maximum displacement at this time is (h 1). Then, the load was removed for 15 seconds until the load reached 0.005mN, and the load was held at 0.005mN for 1 minute, and the recovery rate [ (h1-h2)/h1 ]. times.100 (%) was calculated assuming that the displacement at this time was (h 2). Further, the mahalanobis hardness was obtained from the load-displacement curve at this time.

In the case where the sample to be used in the measurement is resin particles having a size that allows direct application of a load by a pressure roller in the measurement apparatus, the resin particles themselves (1 resin particle) are used as the sample. On the other hand, when the resin particles are of a size such that a load cannot be directly applied by the presser, the constituent components of the resin particles are analyzed by the analyzing means, and a resin film (having an average thickness of 5 μm) is formed using the same components as the constituent components and used as a sample.

In general, a load can be directly applied by a press as long as the resin particles have a volume average particle diameter D50v of 10 μm or more.

The mahalanobis hardness and the recovery rate in the resin particles can be controlled by adjusting the composition of the acrylic urethane resin as the main component of the resin particles. For example, in the case where the acrylic urethane resin is a reaction product of the hydroxyl group-containing acrylic resin (a), the polyol (b) having 2 or more hydroxyl groups and a carbon chain having 6 or more carbon atoms separating the hydroxyl groups, and the polyfunctional isocyanate (c), the mahalanobis hardness and the recovery rate can be adjusted by controlling the hydroxyl value of the acrylic resin (a), the carbon number of the carbon chain spacing between the hydroxyl groups in the long-chain polyol (b), the ratio of the long-chain polyol (b) to the acrylic resin (a), the number of functional groups (isocyanate groups) in the polyfunctional isocyanate (c), the ratio of the polyfunctional isocyanate (c) to the acrylic resin (a), and the like.

Volume average particle diameter D50v

The volume average particle diameter D50v of the resin particles of the present embodiment is 3 μm to 50 μm, preferably 4 μm to 40 μm, and more preferably 5 μm to 30 μm.

By setting the volume average particle diameter D50v to 3 μm or more, the effect (e.g., reduction in gloss) of adding the resin particles to the surface-protecting resin member is improved. On the other hand, by setting the volume average particle diameter D50v to 50 μm or less, when added to a surface-protecting resin member, a surface-protecting resin member having excellent scratch resistance (e.g., self-repairability) can be obtained.

Volume particle size distribution index GSDv

The volume particle size distribution index GSDv of the resin particles of the present embodiment is preferably 1.0 to 1.5, more preferably 1.1 to 1.4, and still more preferably 1.1 to 1.3.

When the volume particle size distribution index GSDv is 1.5 or less, it means that the resin particles have a relatively narrow particle size distribution, and thus when added to a surface-protective resin member, a surface-protective resin member having excellent scratch resistance (for example, self-repairability) can be easily obtained. On the other hand, when the volume particle size distribution index GSDv is 1.0 or more, it means that the particle size may be all uniform so-called monodisperse (in this case, GSD is 1.0) or the particle size distribution may be slightly broadened, thereby making it possible to obtain resin particles with excellent ease of production.

The volume average particle diameter D50v and the volume particle size distribution index GSDv of the resin particles were measured using a Coulter Multisizer II (manufactured by Beckman Coulter) and the electrolyte solution using ISOTON-II (manufactured by Beckman Coulter).

In the measurement, 0.5mg to 50mg of the measurement sample is added as a dispersant to 2ml of a 5% aqueous solution of a surfactant (preferably sodium alkylbenzenesulfonate). The electrolyte is added to 100ml to 150ml of the electrolyte.

The electrolyte solution in which the sample was suspended was dispersed for 1 minute by an ultrasonic disperser, and the particle size distribution of particles having a particle size in the range of 2 μm to 60 μm was measured by a Coulter multisizer II using a pore having a pore diameter of 100 μm. The number of particles sampled was 50000.

A cumulative distribution of the volume from the small diameter side is plotted for a particle size range (channel) obtained by dividing based on the measured particle size distribution, and a particle size at which 16% of the particles are cumulatively defined as a volume particle size D16v, a particle size at which 50% of the particles are cumulatively defined as a volume average particle size D50v, and a particle size at which 84% of the particles are cumulatively defined as a volume particle size D84 v.

Using these values, the volume particle size distribution indicator (GSDv) was (D84v/D16v)^1/2Is calculated.

Average roundness

The average circularity of the resin particles of the present embodiment is preferably 0.8 to 1.0, more preferably 0.85 to 1.0, and further preferably 0.9 to 1.0.

When the average circularity is 1.0 or less, the particles may be spherical (in this case, the circularity is 1.0) or may be not spherical but slightly deformed, and thus the coating properties when a coating film is formed are excellent. On the other hand, when the average circularity is 0.8 or more, it means that the shape of the particles is not excessively deformed, and therefore, when the resin particles are added to a surface-protecting resin member, a surface-protecting resin member having excellent scratch resistance (for example, self-repairability) is easily obtained.

The average circularity of the resin particle is obtained by (equivalent circumference)/(circumference) [ (circumference of circle having the same projected area as the particle image)/(circumference of particle projected image) ]. Specifically, the values were measured by the following methods.

First, a resin particle to be measured is suction-sampled to form a flat flow, a particle image as a still image is acquired by flash emission, and the average circularity is obtained by a flow particle image analyzer (FPIA-3000 manufactured by Sysmex) that performs image analysis on the particle image. The number of samples for obtaining the average circularity is 3500.

Composition of resin particles

The resin particles of the present embodiment contain an acrylic urethane resin as a main component.

Here, the "acrylic urethane resin" refers to a resin having a urethane bond (-NHCOO-) together with a segment derived from an acrylic resin that contains at least an acrylic monomer (for example, a monomer represented by the following formula (ac)) and that may contain a vinyl group (for example, "(R)") in its molecular structure^B)₂-C＝C-(R^B) - "wherein R is as defined above^BEach independently represents a hydrogen atom, a fluorine atom or an alkyl group having 1 to 8 carbon atoms (for example, methyl group, ethyl group, etc.)).

"formula ac: (Rac¹-)₂C＝C(-Rac¹)(-COO-Rac²)”

(in the formula ac, Rac¹Each independently represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms (for example, methyl group, ethyl group, etc.). Rac²Represents an organic group. The organic group includes organic groups containing at least one atom selected from the group consisting of C, H, O and N, and examples thereof include hydrocarbon groups (such as alkyl groups and aryl groups) and fluorinated alkyl groups (such as perfluoroalkyl groups). The above-mentioned hydrocarbon group and fluorinated alkyl group may further have a substituent or a hetero atom (for example, -OH, -O-, -C (═ O) -O-, etc.).

In the present embodiment, the resin particles contain an acrylic urethane resin as a main component, and the content thereof is preferably 50 mass% or more and 100 mass% or less, and more preferably 60 mass% or more and 100 mass% or less with respect to the entire resin particles.

The acrylic urethane resin is obtained, for example, by reacting a hydroxyl group-containing acrylic resin (hydroxyl group-containing acrylic resin) (a) with a polyfunctional isocyanate (c) having 2 or more isocyanate groups in its molecular structure.

In addition, the acrylic urethane resin is more preferably a reaction product of a hydroxyl group-containing acrylic resin (a), a polyol (long-chain polyol) (b) having 2 or more hydroxyl groups and carbon chains of 6 or more carbon atoms separating the hydroxyl groups, and a polyfunctional isocyanate (c), in view of obtaining a surface-protective resin member having excellent scratch resistance (for example, self-healing property) when resin particles are added to the surface-protective resin member.

In addition, from the viewpoint of scratch resistance (for example, self-repairability) of the surface protective resin member, the acrylic urethane resin is more preferably a reaction product of the polymerization component groups of (a), (b), and (c) described above, which is contained in a total amount of 90 mass% or more with respect to the entire polymerization components.

(a) Hydroxyl group-containing acrylic resin

In the present embodiment, a hydroxyl group-containing acrylic resin (a) having a hydroxyl group (-OH) is used as a raw material of the acrylic urethane resin. The hydroxyl group (-OH) contained in the hydroxyl group-containing acrylic resin (a) may be in the form of a carboxyl group (-COOH).

The hydroxyl group can be introduced, for example, by using a polymerizable monomer having a hydroxyl group as a raw material polymerizable monomer of the hydroxyl group-containing acrylic resin (a).

Examples of the polymerizable monomer having a hydroxyl group include (1) an ethylenically polymerizable monomer having a hydroxyl group, such as hydroxymethyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, and N-methylolacrylamide.

Further, (2) an ethylenic polymerizable monomer having a carboxyl group, such as (meth) acrylic acid, crotonic acid, itaconic acid, fumaric acid, and maleic acid, can also be used.

The polymerizable monomer having no hydroxyl group may include ethylenic polymerizable monomers copolymerizable with the polymerizable monomers (1) and (2) (e.g., methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, N-propyl (meth) acrylate, N-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, N-octyl (meth) acrylate, and N-dodecyl (meth) acrylate), (e.g., alkyl (meth) acrylates such as vinyl chloride and vinyl bromide, vinyl cyanides such as acrylonitrile and methacrylonitrile, vinyl esters such as vinyl formate, vinyl acetate, and vinyl propionate, aromatic vinyl derivatives such as styrene, vinyltoluene, and α -methylstyrene, vinylidene halides such as vinylidene chloride and vinylidene fluoride, acrylic acids such as acrylic acid, sodium acrylate, and calcium acrylate, and salts thereof, acrylic acid derivatives such as β -hydroxyethyl acrylate, dimethylaminoethyl acrylate, glycidyl acrylate, acrylamide, N-methylolacrylamide, maleimide methacrylate, and salts thereof, and the like.

In the present specification, "(meth) acrylic acid" means a meaning including both acrylic acid and methacrylic acid, and "(meth) acrylate" means a meaning including both acrylate and methacrylate.

Here, the hydroxyl group-containing acrylic resin (a) may be a reactant of a polymerizable monomer group that contains at least an acrylic monomer and may contain a monomer having a vinyl group, for example. The reactant has a main chain formed by partial polymerization of an ethylenic double bond in each polymerizable monomer, and a side chain bonded to the main chain.

In the case where the acrylic urethane resin contained in the resin particles is a reactant of the hydroxyl group-containing acrylic resin (a), the long-chain polyol (b), and the polyfunctional isocyanate (c), the hydroxyl group-containing acrylic resin (a) may have a content ratio (molar ratio) of a side chain having a hydroxyl group and having a carbon number (carbon number in the side chain portion) of 10 or more (hereinafter also referred to as "long-side-chain hydroxyl group") to a side chain having a hydroxyl group and having a carbon number (carbon number in the side chain portion) of less than 10 (hereinafter also referred to as "short-side-chain hydroxyl group") among all side chains having a hydroxyl group, which is less than 1/3.

Even if the hydroxyl group-containing acrylic resin (a) has a structure in which the ratio of long-side chain hydroxyl groups to short-side chain hydroxyl groups is less than 1/3, that is, even if long-side chain hydroxyl groups are less than short-side chain hydroxyl groups, the acrylic urethane resin tends to have an increased recovery rate and a decreased mahalanobis hardness by further using the long-chain polyol (b). And when the resin particles are added to the surface-protecting resin member, the surface-protecting resin member having excellent scratch resistance (e.g., self-repairability) is easily obtained. As the amount of the long-chain polyol (b) used increases, the recovery rate of the acrylic urethane resin tends to increase and the mahalanobis hardness tends to decrease.

The number of carbon atoms of the side chain part of the short side chain hydroxyl group is less than 10, preferably 6 or less. The number of carbon atoms in the side chain portion of the long-side chain hydroxyl group is 10 or more, preferably 15 or more.

Examples of the polymerizable monomer for introducing a short-side chain hydroxyl group include hydroxymethyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, N-methylolacrylamide, (meth) acrylic acid, crotonic acid, itaconic acid, fumaric acid, and maleic acid.

As the polymerizable monomer for introducing a long-side chain hydroxyl group, a monomer obtained by ring-opening an epsilon-lactone ring, which is a structure that easily enhances elasticity, is preferable, and for example, a monomer obtained by adding 3 to 5 moles of epsilon-caprolactone to 1 mole of hydroxymethyl (meth) acrylate is preferable.

Both the short-side chain hydroxyl group and the long-side chain hydroxyl group may have a structure having no fluorine atom in the structure of the side chain moiety.

Fluorine atom

The hydroxyl group-containing acrylic resin (a) is preferably an acrylic resin having a fluorine atom. By including a fluorine atom in the molecular structure of the hydroxyl group-containing acrylic resin (a), the moldability of molding resin particles into particle shapes can be easily improved.

The introduction of the fluorine atom into the hydroxyl group-containing acrylic resin (a) is carried out, for example, by using a polymerizable monomer having a fluorine atom as a raw material polymerizable monomer of the hydroxyl group-containing acrylic resin (a). Specifically, fluorine atoms can be introduced by using a polymerizable monomer having a group containing a fluorine atom and a vinyl group.

In addition, the vinyl group means a group consisting of "(R)^B-)₂C＝C(-R^B) - "(the above-mentioned R^BEach independently represents a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 8 carbon atoms). As R^BPreferably a hydrogen atom, a fluorine atom or a methyl group. Examples of the vinyl group in the present specification include, for example, CH₂＝CH-、CH₂＝C(CH₃)-、CF₂CF-, etc.

As the polymerizable monomer having a fluorine atom-containing group and a vinyl group, known monomers can be used, and specific examples thereof include trifluoromethyl (meth) acrylate, 2,2, 2-trifluoroethyl (meth) acrylate, 1,1,1,3,3, 3-hexafluoro-2-propyl (meth) acrylate, perfluoroethylmethyl (meth) acrylate, perfluoropropylmethyl (meth) acrylate, perfluorobutylmethyl (meth) acrylate, perfluoropentylmethyl (meth) acrylate, perfluorohexylmethyl (meth) acrylate, perfluoroheptylmethyl (meth) acrylate, perfluorooctylmethyl (meth) acrylate, perfluorononylmethyl (meth) acrylate, perfluorodecylmethyl (meth) acrylate, perfluoroundecylmethyl (meth) acrylate, perfluorododecylmethyl (meth) acrylate, perfluorodecylmethyl (meth) acrylate, perfluoroundecyl methyl (meth) acrylate, and vinyl group, Perfluorotridecyl methyl (meth) acrylate, perfluorotetradecyl methyl (meth) acrylate, 2- (trifluoromethyl) ethyl (meth) acrylate, 2- (perfluoroethyl) ethyl (meth) acrylate, 2- (perfluoropropyl) ethyl (meth) acrylate, 2- (perfluorobutyl) ethyl (meth) acrylate, 2- (perfluoropentyl) ethyl (meth) acrylate, 2- (perfluorohexyl) ethyl (meth) acrylate, 2- (perfluoroheptyl) ethyl (meth) acrylate, 2- (perfluorooctyl) ethyl (meth) acrylate, 2- (perfluorononyl) ethyl (meth) acrylate, 2- (perfluorotridecyl) ethyl (meth) acrylate, 2- (perfluorotetradecyl) ethyl (meth) acrylate, perfluorotetradecyl (meth) acrylate, perfluorododecyl (meth) acrylate, perfluorodecyl) acrylate, Perfluorohexylethylene, hexafluoropropylene epoxide, perfluoro (propyl vinyl ether), and the like.

In the hydroxyl group-containing acrylic resin (a), the side chain having a fluorine atom preferably does not have a group reactive with the long-chain polyol (b) and the polyfunctional isocyanate (c). Therefore, among the polymerizable monomers having a fluorine atom which are the raw materials of the hydroxyl group-containing acrylic resin (a), it is preferable to use a polymerizable monomer which does not have a group reactive with (b) and (c) or has a group reactive with (b) and (c) but does not remain after polymerization.

Examples of the number of carbon atoms of the side chain having a fluorine atom include 2 to 20. The carbon chain in the side chain having a fluorine atom may be linear or branched.

The number of fluorine atoms contained in 1 molecule of the polymerizable monomer having a fluorine atom is not particularly limited, and is, for example, preferably 1 to 25, and more preferably 3 to 17.

In the resin particle of the present embodiment, the content of fluorine atoms is preferably 0.5% by mass or more and 15% by mass or less, more preferably 1% by mass or more and 10% by mass or less, and further preferably 2% by mass or more and 10% by mass or less with respect to the entire resin particle.

By setting the content to 0.5 mass% or more, the moldability of molding the resin particles into a particle shape is easily improved. On the other hand, by setting the content to 15% by mass or less, a surface-protective resin member having excellent scratch resistance (e.g., self-repairability) is easily obtained when the resin particles are added to the surface-protective resin member.

The content of fluorine atoms in the resin particles is adjusted by the proportion of the polymerizable monomer having fluorine atoms in the total polymerizable monomers for synthesizing the hydroxyl-containing acrylic resin (a), the proportion of the hydroxyl-containing acrylic resin (a) to other components (long-chain polyol (b), polyfunctional isocyanate (c), and the like.

The content of fluorine atoms in the resin particles was measured by X-ray photoelectron spectroscopy (XPS) while etching the resin particles with argon clusters (クラスターアルゴン).

Hydroxyl number

The hydroxyl value of the hydroxyl group-containing acrylic resin (a) is preferably from 40 to 280mgKOH/g, more preferably from 70 to 200 mgKOH/g.

By polymerizing an acrylic urethane resin having a hydroxyl value of 40mgKOH/g or more and a high crosslinking density, a surface-protective resin member having excellent scratch resistance (for example, self-repairability) can be easily obtained when resin particles are added to the surface-protective resin member. On the other hand, by setting the hydroxyl value to 280mgKOH/g or less, an acrylic urethane resin having appropriate flexibility can be obtained.

The hydroxyl value of the hydroxyl group-containing acrylic resin (a) is adjusted by, for example, the proportion of the polymerizable monomer having a hydroxyl group in all the polymerizable monomers used for synthesizing the hydroxyl group-containing acrylic resin (a).

The hydroxyl value represents the mg number of potassium hydroxide required for acetylating hydroxyl groups in 1g of the sample. The hydroxyl value in the present embodiment is measured by a method (potentiometric titration method) defined in JIS K0070-1992. When the sample is insoluble, a solvent such as dioxane or Tetrahydrofuran (THF) is used as the solvent.

Molecular weight

The weight average molecular weight of the hydroxyl group-containing acrylic resin (a) is preferably 5000 to 100000, more preferably 10000 to 50000.

By making the weight average molecular weight of the hydroxyl group-containing acrylic resin (a) 5000 or more, a surface-protecting resin member having excellent scratch resistance (e.g., self-repairability) is easily obtained when resin particles are added to the surface-protecting resin member. On the other hand, by setting the weight average molecular weight to 100000 or less, resin particles having excellent flexibility can be easily obtained.

The weight average molecular weight of the hydroxyl group-containing acrylic resin (a) is measured by Gel Permeation Chromatography (GPC). In the molecular weight measurement by GPC, GPC/HLC-8120 GPC manufactured by Toso Co, and TSKgel SuperHM-M (15cm) column manufactured by Toso Co were used as measurement devices, and measurement was performed using Tetrahydrofuran (THF) as a solvent. The weight average molecular weight was calculated from the measurement results using a molecular weight calibration curve prepared using a monodisperse polystyrene standard sample.

The synthesis of the hydroxyl group-containing acrylic resin (a) can be carried out, for example, as follows: the above-mentioned polymerizable monomers are mixed and subjected to ordinary radical polymerization, ion polymerization, or the like, followed by purification, thereby carrying out the synthesis.

(b) Long chain polyols

The long-chain polyol is a polyol having 2 or more hydroxyl groups (-OH) and having a carbon chain in which the number of carbon atoms (the number of carbon atoms of a linear portion connecting the hydroxyl groups) is 6 or more, separated by the hydroxyl groups. That is, the long-chain polyol is a polyol in which all hydroxyl groups are linked to each other by a carbon chain having 6 or more carbon atoms (the number of carbon atoms of the straight chain portion linking the hydroxyl groups to each other).

The number of functional groups of the long-chain polyol (i.e., the number of hydroxyl groups contained in 1 molecule of the long-chain polyol) is, for example, in the range of 2 to 5, and may be 2 to 3.

The carbon chain having 6 or more carbon atoms in the long-chain polyol represents a chain having 6 or more carbon atoms in a linear portion connecting hydroxyl groups to each other. Examples of the carbon chain having 6 or more carbon atoms include an alkylene group, and a 2-valent group in which 1 or more alkylene groups are combined with 1 or more groups selected from the group consisting of-O-, -C (═ O) -, and-C (═ O) -O-. The long-chain polyol having a carbon chain of 6 or more carbon atoms as the hydroxyl group intervening group preferably has- [ CO (CH)₂)_n1O]_n2and-H (here, n1 represents 1 to 10 (preferably 3 or more and 6 or less, more preferably 5), and n2 represents 1 to 50 or less (preferably 1 or more and 35 or less, more preferably 1 to 10)).

Examples of the long-chain polyol include a 2-functional polycaprolactone diol, a 3-functional polycaprolactone triol, and a 4-or more-functional polycaprolactone polyol.

Examples of the 2-functional polycaprolactone diol include, - [ CO (C) ]H₂)_n11O]_n12A compound having 2 groups having a hydroxyl group at the terminal, represented by-H (herein, n11 represents 1 to 10 (preferably 3 or more and 6 or less, more preferably 5), and n12 represents 1 to 50 or less (preferably 4 or more and 35 or less)). Among them, compounds represented by the following general formula (1) are preferable.

(in the general formula (1), R represents an alkylene group, or a 2-valent group in which an alkylene group and 1 or more groups selected from the group consisting of-O-and-C (═ O) -are combined, and m and n each independently represent an integer of 1 to 35.)

In the general formula (1), the alkylene group contained in the 2-valent group represented by R may be linear or branched. The alkylene group is preferably an alkylene group having 1 to 10 carbon atoms, and more preferably an alkylene group having 1 to 5 carbon atoms.

The 2-valent group represented by R is preferably a linear or branched alkylene group having 1 to 10 carbon atoms (preferably 2 to 5 carbon atoms), and more preferably a group in which 2 linear or branched alkylene groups having 1 to 5 carbon atoms (preferably 1 to 3 carbon atoms) are linked via — O-or-C (═ O) - (preferably-O-). Of these, more preferred is-C₂H₄-*、*-C₂H₄OC₂H₄-C (CH)₃)₂-(CH₂)₂-. It is to be noted that the above-listed 2-valent groups are bonded to each other at "" portions.

m and n each independently represent an integer of 1 to 35, preferably 2 to 10.

Examples of the 3-functional polycaprolactone triol include [ -CO (CH)₂)_n21O]_n22A compound having 3 groups having a hydroxyl group at the terminal, represented by-H (here, n21 represents 1 to 10 (preferably 3 or more and 6 or less, more preferably 5), and n22 represents 1 to 50 or less (preferably 1 to 28 or less)). Among them, compounds represented by the following general formula (2) are preferable.

(in the general formula (2), R represents a 3-valent group obtained by removing 1 hydrogen atom from an alkylene group, or a 3-valent group obtained by removing 1 hydrogen atom from an alkylene group and combining 1 or more groups selected from the group consisting of alkylene groups, -O-and-C (═ O) -.l, m and n each independently represent an integer of 1 to 28, and l + m + n is 3 to 30.)

In the general formula (2), when R represents a 3-valent group obtained by removing 1 hydrogen atom from an alkylene group, the group may be linear or branched. The 3-valent group obtained by removing 1 hydrogen atom from the alkylene group is, for example, preferably an alkylene group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 6 carbon atoms.

In addition, R may be a 3-valent group obtained by combining 1 or more groups selected from the group consisting of alkylene groups (e.g., alkylene groups having 1 to 10 carbon atoms), — O ", and — C (═ O) -, with a 3-valent group obtained by removing 1 hydrogen atom from the alkylene group shown above.

The 3-valent group represented by R is preferably a 3-valent group obtained by removing 1 hydrogen atom from a linear or branched alkylene group having 1 to 10 carbon atoms (preferably, having 3 to 6 carbon atoms). Of these, more preferred is-CH₂-CH(-*)-CH₂-*、CH₃-C(-*)(-*)-(CH₂)₂-*、CH₃CH₂C(-*)(-*)(CH₂)₃3-valent group represented by. It is to be noted that the above-listed 3-valent groups are bonded to each other at "" portions.

l, m and n each independently represent an integer of 1 to 28, preferably 2 to 10. l + m + n is 3 to 30, preferably 6 to 30.

The long-chain polyol preferably has a hydroxyl value of not less than 30mgKOH/g and not more than 300mgKOH/g, and more preferably has a hydroxyl value of not less than 50mgKOH/g and not more than 250 mgKOH/g. Polymerizing an acrylic urethane resin having a hydroxyl value of 30mgKOH/g or more and a high crosslinking density; on the other hand, by setting the hydroxyl value to 300mgKOH/g or less, an acrylic urethane resin having appropriate flexibility can be easily obtained.

The hydroxyl value represents the mg number of potassium hydroxide required for acetylating hydroxyl groups in 1g of the sample. In the measurement of the hydroxyl value in the present embodiment, the measurement is carried out according to the method (potentiometric titration) defined in JIS K0070-1992. When the sample is insoluble, a solvent such as dioxane or THF is used as the solvent.

Than [ OH ]_A/OH_B]

Hydroxyl value [ OH ] of the hydroxyl group-containing acrylic resin (a)_A]Hydroxyl value [ OH ] with Long-chain polyol (b)_B]Ratio of [ OH ]_A/OH_B]Preferably 0.1 to 3, more preferably 0.2 to 2.5, and further preferably 0.3 to 2.0.

By making the ratio [ OH_A/OH_B]An acrylic urethane resin having a high crosslinking density of 0.1 or more is polymerized, and when resin particles are added to a surface-protecting resin member, a surface-protecting resin member having excellent scratch resistance (for example, self-repairability) can be easily obtained. On the other hand, by making the ratio [ OH_A/OH_B]An acrylic urethane resin having appropriate flexibility can be easily obtained at a content of 3 or less.

(c) Polyfunctional isocyanates

The polyfunctional isocyanate (c) is a compound having 2 or more isocyanate groups (-NCO), and reacts with, for example, a hydroxyl group of the hydroxyl group-containing acrylic resin (a), a hydroxyl group of the long-chain polyol (b), or the like to form a urethane bond (-NHCOO-). And functions as a crosslinking agent for crosslinking the hydroxyl group-containing acrylic resins (a) with each other and the hydroxyl group-containing acrylic resin (a), the long-chain polyol (b) and the long-chain polyol (b) with each other.

The polyfunctional isocyanate is not particularly limited, and examples thereof include 2-functional diisocyanates such as methylene diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. Also, polyfunctional isocyanates having a biuret structure, an isocyanurate structure, an addition structure, an elastic structure, and the like in the polymer of hexamethylene polyisocyanate are preferably used.

The polyfunctional isocyanate may be a commercially available product, and examples thereof include polyisocyanate (Duranate) manufactured by Asahi Kasei corporation.

The polyfunctional isocyanate may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The amount of the polyfunctional isocyanate is preferably adjusted so that the ratio of isocyanate groups (-NCO) is 0.8 to 1.5 in terms of a molar ratio, and more preferably 1 to 1.3 in terms of a molar ratio, with respect to the total amount of hydroxyl groups (-OH) in the hydroxyl group-containing acrylic resin (a) and the long-chain polyol (b).

When the amount of the polyfunctional isocyanate is 0.8 or more in the above molar ratio and the acrylic urethane resin having a high crosslinking density is polymerized, a surface-protecting resin member having excellent scratch resistance (for example, self-repairability) can be easily obtained when resin particles are added to the surface-protecting resin member. On the other hand, when the amount of the polyfunctional isocyanate is 1.6 or less in the above molar ratio, an acrylic urethane resin having appropriate elasticity can be easily obtained.

(e) Other additives

In the present embodiment, other additives may be contained in the resin particles. Examples of the other additives include a colorant, an antistatic agent, and a reaction accelerator for accelerating a reaction between hydroxyl groups (-OH) in the hydroxyl group-containing acrylic resin (a) and the long-chain polyol (b) and isocyanate groups (-NCO) in the polyfunctional isocyanate (c).

Colorants

Examples of the colorant include various pigments such as carbon black, chrome yellow, hansa yellow, benzidine yellow, vat yellow (スレンイエロー), quinoline yellow, pigment yellow, permanent orange GTR, pyrazolone orange, sulfur-resistant orange, lake red, permanent red, brilliant carmine 3B, brilliant carmine 6B, dupont oil red, pyrazolone red, lithol red, rhodamine B lake, lake red C, pigment red, rose red, aniline blue, azure blue, oil blue (カルコオイルブルー), methylene blue chloride, phthalocyanine blue, pigment blue, phthalocyanine green, and malachite green oxalate; or various dyes such as acridine, xanthene, azo, benzoquinone, azine, anthraquinone, thioindigo, dioxazine, thiazine, azomethine, indigo, phthalocyanine, nigrosine, polymethine, triphenylmethane, diphenylmethane, and thiadiazole.

The colorant may be a surface-treated colorant as required, or may be used in combination with a dispersant. Two or more kinds of the coloring agents may be used in combination.

The content of the colorant is, for example, preferably 1.0 mass% to 40 mass%, more preferably 2.0 mass% to 30 mass% with respect to the entire resin particles.

Antistatic agents

Specific examples of the antistatic agent include cationic surface active compounds (e.g., tetraalkylammonium salts, trialkylbenzylammonium salts, hydrochloride salts of alkylamines, imidazolium salts, etc.), anionic surface active compounds (e.g., alkylsulfonates, alkylbenzenesulfonates, alkylphosphates, etc.), nonionic surface active compounds (e.g., glycerin fatty acid esters, polyoxyalkylene ethers, polyoxyethylene alkylphenyl ethers, N-bis 2-hydroxyethylalkylamines, hydroxyalkylmonoethanolamine, polyoxyethylene alkylamines, fatty acid diethanolamides, polyoxyethylene alkylamine fatty acid esters, etc.), amphoteric surface active compounds (e.g., alkylbetaines, alkylimidazolium betaines, etc.), and the like.

Further, examples of the antistatic agent include those containing quaternary ammonium.

Specific examples thereof include tri-n-butylmethylammonium bistrifluoromethanesulfonimide, lauryltrimethylammonium chloride, octyldimethylethylammonium ethylsulfate, didecyldimethylammonium chloride, lauryldimethylbenzylammonium chloride, stearyldimethylhydroxyethylammonium p-toluenesulfonate, tributylbenzylammonium chloride, lauryldimethylaminoacetic acid betaine, lauramidopropylbetaine, octylamidopropylbetaine, and polyoxyethylene stearylamine hydrochloride. Among these, tri-n-butylmethylammonium bistrifluoromethanesulfonimide is preferable.

High molecular weight antistatic agents may also be used.

Examples of the high molecular weight antistatic agent 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, an ethylene oxide-epichlorohydrin type polymer compound, and a polyether ester amide type polymer compound.

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

(in the structural unit (A), R¹Represents a hydrogen atom or a methyl group, R²、R³And R⁴Each independently represents an alkyl group, X^-Represents an anion. )

The polymerization of the high molecular weight antistatic agent can be carried out by a known method.

The high molecular weight antistatic agent may be a polymer compound composed of the same polymerizable monomer alone, or 2 or more polymer compounds composed of different polymerizable monomers may be used in combination.

In the present embodiment, the surface resistance of the surface-protecting resin member to be formed is preferably adjusted to 1 × 10⁹1 × 10 above omega/□¹⁴Omega/□ or less, and the volume resistance is preferably adjusted to 1X 10⁸1 × 10 at a height of Ω cm¹³The range of not more than Ω cm.

The surface resistance and volume resistance were measured by using a UPMCP-450 type UR probe, a high resistivity meter manufactured by Diamond Instruments (manufactured by Kogyo Co., Ltd.), at 22 ℃ and 55% RH in accordance with JIS-K6911.

When the surface-protecting resin member contains an antistatic agent, the surface resistance and the volume resistance of the surface-protecting resin member can be controlled by adjusting the kind, the content, and the like of the antistatic agent.

The antistatic agent can be used singly or in combination of more than 2.

Reaction accelerator

A reaction accelerator for accelerating the reaction between the hydroxyl group (-OH) in the hydroxyl group-containing acrylic resin (a) and the long-chain polyol (b) and the isocyanate group (-NCO) in the polyfunctional isocyanate (c) may be added. Examples of the accelerator include metal catalysts such as stannous octoate, dibutyltin diacetate, dibutyltin dilaurate, bismuth octoate, and bismuth decanoate. Examples thereof include Neostan U-28, U-50, and U-600 available from Nidong Kabushiki Kaisha.

Method for producing resin particles

The resin particles of the present embodiment contain an acrylic urethane resin as a main component, and have a mahalanobis hardness, a recovery rate, and a volume average particle diameter D50v in the above-described ranges, and a method for producing the resin particles will be described in detail below.

The resin particle of the present embodiment is not limited to a production method thereof as long as it satisfies the above requirements. Among them, from the viewpoint of easily producing resin particles satisfying the above requirements, it is preferable to produce the resin particles by a wet process such as a dissolution suspension method.

Dissolution suspension method

As a dissolution suspension method for producing the resin particles of the present embodiment, a method having the following steps can be mentioned: an oil phase preparation step of dissolving or dispersing at least a polymerization component (for example, the above-mentioned hydroxyl group-containing acrylic resin (a), long-chain polyol (b), polyfunctional isocyanate (c), etc.) in an organic solvent to prepare an oil phase; a granulation step of suspending and granulating the oil phase component in an aqueous phase; and a solvent removal step of removing the solvent.

(oil phase preparation Process)

In the dissolution suspension method, first, the polymerization components (for example, the above-mentioned hydroxyl group-containing acrylic resin (a), long-chain polyol (b), polyfunctional isocyanate (c), etc.) are dissolved or dispersed in an organic solvent to prepare an oil phase.

Organic solvents that can be used depend on the kind of polymerization components, and hydrocarbons such as toluene, xylene, hexane, etc. are generally used; halogenated hydrocarbons such as dichloromethane, chloroform, dichloroethane and the like; alcohols or ethers such as ethanol, butanol, benzyl alcohol ether, and tetrahydrofuran; esters such as methyl acetate, ethyl acetate, butyl acetate, isopropyl acetate, etc.; ketones such as acetone, methyl ethyl ketone, diisobutyl ketone, cyclohexanone, and methylcyclohexane. The mass ratio of the polymerization component to the solvent used in the oil phase is preferably in the range of 10:90 to 80:20 from the viewpoint of ease of granulation or yield of the final resin particles.

In the present embodiment, when an additive such as a colorant is added to the resin particles, it is preferable to prepare an additive dispersion liquid in which the additive is dispersed in advance with a synergist and a dispersant before the preparation of the oil phase, and mix the additive dispersion liquid with the polymerization components (for example, the components (a), (b), and (c) described above). When preparing the additive dispersion, the synergist and the dispersant are first attached to the additive. The additive is attached to the substrate by using a conventional stirring apparatus. Specifically, the following method was used: the additives, synergists and dispersants are charged into a vessel equipped with a granular medium, such as an attritor, a ball mill, a sand mill, a vibration mill, etc., the vessel is kept at a preferred temperature range, for example, a temperature range of 20 ℃ to 160 ℃, and stirred.

(granulation Process)

Next, these oil phase components are suspension granulated so as to have a desired particle size in the water phase. The main medium of the aqueous phase is water, and a mixed dispersant is preferred. Further, the salt may be added to water and used in the form of a salt solution.

The dispersant stabilizes the dispersion of the oil phase droplets by forming a hydrophilic colloid. Examples of the inorganic dispersant include calcium carbonate, magnesium carbonate, barium carbonate, tricalcium phosphate, hydroxyapatite, diatomaceous silica, and clay.

These inorganic dispersants may be used in combination with an organic dispersant. Specific examples of the organic dispersant include gelatin, gelatin derivatives (e.g., acetylated gelatin, phthalated gelatin, succinylated gelatin), proteins such as albumin and casein, collodion, gum arabic, agar, alginic acid, cellulose derivatives (e.g., alkyl esters of carboxymethyl cellulose, hydroxymethyl cellulose, carboxymethyl cellulose, etc.), synthetic polymers (e.g., polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polyacrylate, polymethacrylate, polymaleate, polystyrene sulfonate), and the like.

These dispersants may be used alone, or two or more kinds may be used in combination.

The dispersant is preferably used in a range of 0.001 to 5 mass% with respect to the main medium of the aqueous phase.

A dispersion aid may be further incorporated in the aqueous phase. The dispersion aid is preferably a surfactant, and examples thereof include ionic and nonionic surfactants. These dispersion aids may be used alone or in combination of two or more. The dispersion aid is preferably used in a range of 0.001 to 5 mass% with respect to the main medium of the aqueous phase.

The mixing ratio of the oil phase and the aqueous phase varies depending on the particle diameter of the final resin particles and the manufacturing apparatus, and the oil phase/aqueous phase is preferably in the range of 10/90 to 90/10 in terms of mass ratio. Further, granulation of the oil phase in the aqueous phase is preferably performed under high-speed shear. It should be noted that, as the particle size of the resin particles to be produced becomes smaller, attention is paid to selection of the disperser provided with the high-speed shearing mechanism to be used. Among them, high-speed paddle rotary type or forced interval passage type emulsion dispersers such as homomixers, homogenizers, colloid mills, ULTRA-TURRAX, Clear Mill (クレアミル), etc. are suitable.

(solvent removal step)

The solvent (organic solvent) is removed during or after the granulation step. The solvent may be removed at normal temperature (e.g., 25 ℃) or under reduced pressure. In order to proceed at normal temperature, it is preferable to apply a temperature lower than the boiling point of the solvent in consideration of the glass transition temperature Tg of the resin (acrylic urethane resin). If the temperature is significantly higher than the Tg of the resin, fusion of the resin particles may be caused.

For example, although depending on the amount of the reaction accelerator added, granulation may be generally performed as follows: the mixture was stirred at 40 ℃ for 1 to 3 hours to remove the solvent, and then stirred at 60 ℃ for 2 to 6 hours to cause a crosslinking reaction, thereby obtaining pellets. The pressure reduction is preferably performed at 20mmHg to 150 mmHg.

The obtained granulated substance (slurry substance) is preferably washed with an acid capable of dissolving the inorganic dispersant in water, such as hydrochloric acid, nitric acid, formic acid, or acetic acid, after removing the solvent. This can remove the inorganic dispersant remaining on the surface of the resin particles. The granulated product treated with the acid can be washed again with an alkali water such as sodium hydroxide. By placing the resin particles in an acidic atmosphere in this manner, a part of the ionic substance on the surface of the insoluble resin particles is dissolved again and removed, and the charging property and the powder flowability can be improved. It is more preferable to adjust conditions such as pH at the time of washing, the number of times of washing, and temperature at the time of washing, and to use a stirrer, an ultrasonic dispersion device, and the like, since washing can be performed efficiently. Thereafter, the resin particles can be obtained by performing steps such as filtration, decantation, centrifugation and the like, and drying.

The drying can be carried out by conventional drying methods. Examples of the method include a method using a pneumatic dryer, for example, a drying treatment using a flash air dryer, a treatment using a fluidized Bed (fluidized Bed), and the like. Further, a freeze-drying method can be used. In particular, in the absence of fluorine atoms, coagulation is likely to occur in the drying step, and therefore, a freeze-drying method can be suitably used.

< surface protective resin Member >

Embodiment 1

The surface-protecting resin member according to embodiment 1 includes a resin and resin particles for adding the surface-protecting resin member according to the present embodiment dispersed in the resin.

That is, the resin particles of the present embodiment are dispersed in the continuous phase of the resin.

By having the above-described configuration, a surface-protecting resin member having excellent scratch resistance (e.g., self-repairability) can be obtained.

Embodiment 2

The surface-protecting resin member in the present embodiment is not limited to the surface-protecting resin member of embodiment 1.

That is, the surface-protecting resin member according to embodiment 2 includes a resin and resin particles dispersed in the resin, and the volume average particle diameter D50v is 3 μm or more and 50 μm or less, and the amount of the resin particles added to the entire surface-protecting resin member is 5 vol% or more and 50 vol% or less; the surface-protecting resin member had a Martensitic hardness at 23 ℃ of 0.5N/mm²Above 220N/mm²The recovery rate at 23 ℃ is 70% to 100%.

The surface-protecting resin member according to embodiment 2, having the above-described configuration, exhibits excellent self-repairability despite the presence of the interface between the resin particles and the resin constituting the continuous phase.

The surface-protecting resin member according to embodiment 2 is not particularly limited, but can be realized by using, for example, the resin particles for adding the surface-protecting resin member according to the present embodiment as the resin particles.

Martensitic hardness of surface-protecting resin Member

The surface-protecting resin member of embodiment 2 has a Martensitic hardness of 0.5N/mm at 23 DEG C²Above 220N/mm²The following. Preferably 1N/mm²Above 80N/mm²Below, more preferably 1N/mm²Above 5N/mm²The following.

By setting the Martensitic hardness (23 ℃) at 220N/mm²Hereinafter, excellent self-repairing properties can be obtained. On the other hand, the Martensitic hardness (23 ℃ C.) was adjusted to 0.5N/mm²As described above, the shape required for the surface-protecting resin member can be easily maintained.

The surface-protecting resin member according to embodiment 1 also preferably has a mahalanobis hardness at 23 ℃.

Recovery ratio of surface protective resin Member

The surface protection resin member according to embodiment 2 has a recovery rate at 23 ℃ of 70% to 100%, preferably 80% to 100%, and more preferably 90% to 100%.

The recovery rate is an index indicating the self-repairability (the property of the deformation due to stress recovering within 1 minute after the removal of the load of stress, that is, the degree of damage repair) of the surface protective resin member. That is, by setting the recovery rate (23 ℃) to 70% or more, the easiness of repair of the damage (i.e., self-repairability) is improved.

The surface protection resin member according to embodiment 1 also preferably has a recovery rate at 23 ℃.

In the measurement of the mahalanobis hardness and the recovery rate of the surface protective resin member, a Fischer scope HM2000 (manufactured by Fischer corporation) was used as a measurement device, and a sample (surface protective resin member) was fixed to a slide glass with an adhesive and set in the measurement device. The sample was applied with a load of up to 0.5mN for 15 seconds at a specific measurement temperature (e.g., 23 ℃) and held at 0.5mN for 5 seconds. The maximum displacement at this time is (h 1). Then, the load was removed for 15 seconds until the load reached 0.005mN, and the load was held at 0.005mN for 1 minute, and the recovery rate [ (h1-h2)/h1 ]. times.100 (%) was calculated assuming that the displacement at this time was (h 2). Further, the mahalanobis hardness was obtained from the load-displacement curve at this time.

Surface roughness Ra of surface-protecting resin Member

The surface roughness Ra of the surface-protecting resin member according to embodiment 1 or 2 is preferably 0.2 μm or more and 10 μm or less, more preferably 0.3 μm or more and 8 μm or less, and further preferably 0.4 μm or more and 5 μm or less.

When the surface roughness Ra is 0.2 μm or more, the surface glossiness is lowered, and the matting effect is easily improved. On the other hand, by setting the surface roughness Ra to 10 μm or less, the effect of suppressing the deterioration of the scratch resistance is easily obtained.

The surface roughness Ra of the surface-protecting resin member is controlled by adjusting the particle size, the amount of addition, or the like of the added resin particles.

In the measurement of the surface roughness Ra (center line average roughness) of the surface protective resin member, 3 measurements were randomly performed on the surface of the surface protective resin member according to JISB0601(1994), and the average value thereof was obtained. As the measuring apparatus, SURFCOM1400 manufactured by tokyo precision co was used, and the cut-off value (cutoff) was 0.8mm, the measuring length was 2.4mm, and the sliding speed (トラバーススピード) of the drive case was 0.3mm/sec as the measuring conditions.

Average thickness of surface protective resin Member

The surface-protecting resin member according to embodiment 1 or 2 preferably has an average thickness of 5 μm to 100 μm, more preferably 10 μm to 80 μm, and still more preferably 20 μm to 60 μm.

By setting the average thickness to 5 μm or more, excellent scratch resistance (for example, self-repairability) can be easily obtained. On the other hand, by setting the average thickness to 100 μm or less, the ease of molding of the surface-protecting resin member is easily improved.

The average thickness of the surface-protecting resin member can be measured using a known apparatus and method. For example, in the case of a plate-like or sheet-like substrate, 10 measurements are randomly made on the substrate on which the surface-protecting resin member is formed, and the film thickness of the substrate is subtracted from each of the measurements to calculate an average value, and this average value is defined as the average thickness. As the measuring apparatus, a usual micrometer such as a micrometer (model: MDH-25MB) manufactured by Mitutoyo, K.K. can be used.

Addition amount of resin particles in surface-protective resin member

In the surface-protecting resin member according to embodiment 2, the amount of the resin particles added is 5 vol% or more and 50 vol% or less. Preferably 6 vol% or more and 40 vol% or less, and more preferably 8 vol% or more and 30 vol% or less.

When the amount of the resin particles added is 5 vol% or more, the surface glossiness is lowered, and the matting effect is easily improved. On the other hand, by setting the amount of the resin particles to 50% by volume or less, excellent scratch resistance (for example, self-repairability) can be easily obtained.

The amount of the resin particles added to the surface-protecting resin member according to embodiment 1 is also preferably within the above range.

Composition of continuous phase (resin) in surface-protecting resin Member

In the surface-protecting resin member according to embodiment 1 or 2, a resin having scratch resistance (for example, self-repairability) is suitably used as the resin forming the continuous phase.

The resin having scratch resistance (for example, self-healing property) to form the continuous phase is not particularly limited, and a known resin can be used. Among them, when the resin particles according to the present embodiment are used as the resin particles to be added, an acrylic urethane resin is preferable from the viewpoint of compatibility with the resin particles.

The acrylic urethane resin forming the continuous phase is obtained, for example, by reacting an acrylic resin containing a hydroxyl group in the molecular structure (specifically, the hydroxyl group-containing acrylic resin (a)) with an isocyanate having 2 or more isocyanate groups (specifically, the polyfunctional isocyanate (c)).

In addition, from the viewpoint of obtaining a surface-protecting resin member having excellent scratch resistance (for example, self-repairability), it is more preferable to use the "reaction product of the hydroxyl group-containing acrylic resin (a), the polyol (long-chain polyol) (b) having 2 or more hydroxyl groups and a carbon chain having 6 or more carbon atoms separating the hydroxyl groups, and the polyfunctional isocyanate (c)" described in the section of the resin particles in the present embodiment, in the resin forming the continuous phase.

From the viewpoint of scratch resistance (for example, self-repairability), the urethane acrylate resin as the resin forming the continuous phase is more preferably a reaction product containing the polymerization component groups of (a), (b), and (c) in a total amount of 90 mass% or more with respect to the entire polymerization components.

In the case where an acrylic urethane resin is used for both the resin forming the continuous phase and the resin as the main component in the resin particles, it is preferable that only one of the acrylic urethane resin forming the continuous phase and the acrylic urethane resin as the main component of the resin particles contains a fluorine atom (for example, a reactant in which a hydroxyl group-containing acrylic resin (a) having a fluorine atom is used as a polymerization component) from the viewpoint of suppressing repulsion of the resin particles added to the continuous phase and improving dispersibility.

Further, in view of the ease of improving the moldability of the resin particles into particle shapes, it is preferable that the acrylic urethane resin forming the continuous phase contains no fluorine atoms, but the acrylic urethane resin as the main component of the resin particles contains fluorine atoms (for example, a reaction product obtained by using a hydroxyl group-containing acrylic resin (a) having a fluorine atom as a polymerization component).

The surface-protecting resin member according to embodiment 1 or 2 is formed by, for example, the following method.

For example, the hydroxyl group-containing acrylic resin (a), the long-chain polyol (b), the polyfunctional isocyanate (c), and the resin particles (for example, the resin particles of the present embodiment) are mixed, deaerated under reduced pressure, and cast onto a substrate (for example, a polyimide film, an aluminum plate, a glass plate, or the like) to form a resin layer. Subsequently, the surface-protecting resin member can be formed by heating (for example, at 85 ℃ C. for 60 minutes, and then at 130 ℃ C. for 0.5 hour) to cure the resin.

In the present embodiment, the method for forming the surface-protecting resin member is not limited to the above-described method. For example, in the case of using a blocked polyfunctional isocyanate, it is preferable to heat the resin composition to a temperature at which the blocking is released or higher to cure the resin composition. Polymerization can be performed by a method such as using ultrasonic waves instead of vacuum degassing or degassing by leaving the mixed solution to stand.

[ use ]

The surface-protecting resin member according to the present embodiment (embodiment 1 or embodiment 2) can be used as a surface-protecting member for an article, for example, an article whose surface may be scratched by contact with a foreign substance. In addition, the composition is particularly suitable for applications requiring low surface gloss (for example, applications requiring matte properties).

Specifically, applications requiring a low surface gloss include interior materials (for example, wall materials as building materials, interior materials for automobiles, and the like), furniture (for example, sofas, and the like), leather products (for example, bags, rucksacks, and the like), floor materials, tiles, and the like.

In addition, in a portable device (for example, a mobile phone, a portable game machine, or the like), a screen of a touch panel, a building material, a member for an automobile (for example, a body of a car, a handle of a door, or the like), a container (for example, a suitcase or the like), a container for cosmetics, glasses (for example, a frame, a lens, or the like), sporting goods (for example, a golf club, a racket, or the like), a writing instrument (for example, a pen or the like), a musical instrument (for example, an exterior of a piano, or the like), a clothes storing step (for example, a clothes hanger or the like), a member for an image forming apparatus such as a copying machine (for example.