WO2018168987A1

WO2018168987A1 - Coating material for vehicle interior members, vehicle interior member and method for producing vehicle interior member

Info

Publication number: WO2018168987A1
Application number: PCT/JP2018/010137
Authority: WO
Inventors: 修平尾知; ヤンシェンセドリックチン; 俊齋藤
Original assignee: Ａｇｃ株式会社
Priority date: 2017-03-15
Filing date: 2018-03-15
Publication date: 2018-09-20
Also published as: JPWO2018168987A1; JP7031660B2

Abstract

Provided is a coating material for vehicle interior members, which is capable of forming a vehicle interior member that has excellent scratch resistance and excellent contamination resistance against sunscreen agents. A coating material for vehicle interior members, which is characterized by containing a fluorine-containing polymer that has a unit based on a fluoroolefin and a unit based on a monomer having a first crosslinkable group, a polyrotaxane that has two or more second crosslinkable groups, and a curing agent.

Description

Paint for vehicle interior member, vehicle interior member, and method for manufacturing vehicle interior member

The present invention relates to a paint for a vehicle interior member, a vehicle interior member, and a method for manufacturing the vehicle interior member.

Vehicle interior components (dashboard (instrument panel), center console, door trim, center cluster, switch panel, shift knob, etc.) are hardened by curing the paint for the purpose of protecting the surface, decorating or improving the touch. May have a membrane. Such a paint is used by painting directly on a vehicle interior base material constituting the vehicle interior member or by painting on a film used by being attached to the vehicle interior base material.
In a vehicle interior member, the contamination of the member due to the sunscreen agent adhering may be a problem, and the vehicle interior member is required to be resistant to contamination.
Patent Document 1 discloses a vehicle interior member film using a fluoropolymer.

JP 2014-139019 A

The vehicle interior member is also required to have excellent scratch resistance.
As a result of examining the prior art, the present inventors have found that it is impossible to achieve both the stain resistance and the scratch resistance for sunscreen agents.

The present invention has been made in view of the above problems, and is formed using a paint for a vehicle interior member capable of forming a vehicle interior member excellent in scratch resistance and anti-staining properties against sunscreen agents, and the same. An object of the present invention is to provide a vehicle interior member having a cured film and a method for manufacturing the same.

As a result of intensive studies on the above problems, the present inventors can obtain a desired effect when using a paint containing a fluorine-containing polymer having a crosslinkable group, a polyrotaxane having a crosslinkable group, and a curing agent. As a result, they have reached the present invention.
That is, the present inventors have found that the above problem can be solved by the following configuration.

(1) a fluoropolymer containing a unit based on a fluoroolefin and a unit based on a monomer having a first crosslinkable group, a polyrotaxane having two or more second crosslinkable groups, and the first crosslinkable property And a curing agent having two or more functional groups capable of reacting with at least one of the group and the second crosslinkable group.
(2) The coating material according to (1), wherein the fluoropolymer has a glass transition temperature of 50 ° C. or higher.
(3) The fluoropolymer further includes units based on a monomer having an alkyl group having a tertiary carbon atom having 3 to 9 carbon atoms or a cycloalkyl group having 4 to 10 carbon atoms in the side chain; The coating material according to (1) or (2), wherein the content of the unit is 10 to 45 mol% with respect to all the units contained in the fluoropolymer.
(4) The content of the unit based on the monomer having the first crosslinkable group is 1 to 40 mol% with respect to the total units contained in the fluoropolymer, (1) to (3) The coating material in any one of.
(5) The paint according to any one of (1) to (4), wherein the first crosslinkable group is a hydroxy group, and the hydroxy value of the fluoropolymer is 1 to 150 mgKOH / g.

(6) The paint according to any one of (1) to (5), wherein a ratio of a mass of the fluoropolymer to a mass of the polyrotaxane is 1.5 or more.
(7) The paint according to any one of (1) to (6), wherein the polyrotaxane has a glass transition temperature of 0 ° C. or lower.
(8) The polyrotaxane is a polyrotaxane having a cyclodextrin as a cyclic molecule and a polyethylene glycol having both ends blocked with blocking groups as an axis molecule, or a cyclic ester-modified product or a cyclic ether-modified product of the polyrotaxane, (1 ) To (7).
(9) The paint according to any one of (1) to (8), wherein the second crosslinkable group is a hydroxy group or a carboxy group.
(10) The coating material according to (9), wherein the second crosslinkable group is a hydroxy group, and the polyrotaxane has a hydroxyl value of 200 mgKOH / g or less.

(11) The coating material according to any one of (1) to (10), wherein the polyrotaxane has an axial molecular weight average molecular weight of 1,000 or more.
(12) The coating material according to any one of (1) to (11), wherein the content of the polyrotaxane is 0.1 to 30% by mass with respect to the total amount of the fluoropolymer, the polyrotaxane and the curing agent. .
(13) The first crosslinkable group and the second crosslinkable group are both hydroxy groups, and the curing agent is an isocyanate curing agent, according to any one of (1) to (12) paint.
(14) A vehicle interior member having a vehicle interior base material and a cured film formed from the paint according to any one of (1) to (13) disposed on the vehicle interior base material.
(15) A vehicle interior member that forms a coating film by applying the coating material according to any one of (1) to (13) on a vehicle interior base material, and forms a cured film by curing the coating film. Manufacturing method.

ADVANTAGE OF THE INVENTION According to this invention, the vehicle interior member coating material which can form the vehicle interior member excellent in damage resistance with respect to a scratch resistance and a sunscreen agent, and the vehicle interior member which has a cured film formed using this coating material, and The manufacturing method can be provided.

The meanings of terms in the present invention are as follows.
“Unit” is a general term for an atomic group derived from one monomer molecule formed directly by polymerization of a monomer and an atomic group obtained by chemical conversion of a part of the atomic group. is there. The content (mol%) of each unit with respect to all units contained in the polymer can be determined from the charged amount of each monomer.
“Acid value” and “hydroxyl value” are values measured according to the method of JIS K 0070-3 (1992), respectively.
“Glass transition temperature” is a value measured by the method defined in JIS K 6240 (2011). “Glass transition temperature” is also referred to as “Tg”.
“Number average molecular weight” and “weight average molecular weight” are values measured by gel permeation chromatography using polystyrene as a standard substance. “Number average molecular weight” is also referred to as “Mn”, and “weight average molecular weight” is also referred to as “Mw”.
“Fluorine content” means the ratio (% by mass) of fluorine atoms to the total mass of the fluoropolymer. The fluorine content can be determined by analyzing the fluoropolymer by nuclear magnetic resonance spectroscopy.

The paint for vehicle interior members of the present invention (hereinafter also referred to as “the present paint”) includes a crosslinkable fluorine-containing heavy containing a unit based on a fluoroolefin and a unit based on a monomer having a first crosslinkable group. A paint comprising a coalesced polymer, a crosslinkable polyrotaxane having two or more second crosslinkable groups, and a curing agent. In the following, the term “stain resistance” refers to the resistance to contamination with sunscreens such as Copatone (registered trademark).
The present inventors have found that a vehicle interior member including a cured film formed from the paint containing a crosslinkable fluoropolymer and a crosslinkable polyrotaxane can achieve both scratch resistance and stain resistance at a high level. ing. Further, as shown in the examples described later, the vehicle interior member having a cured film of a paint containing a crosslinkable polymer other than the crosslinkable fluoropolymer and the crosslinkable polyrotaxane has deteriorated stain resistance. I also know that.

The fluoropolymer in the present invention is a monomer having a unit based on a fluoroolefin (hereinafter also referred to as “unit F”) and a first crosslinkable group (hereinafter also referred to as “monomer C”). It is a fluorine-containing polymer having a first crosslinkable group, which includes a unit based on (hereinafter also referred to as “unit C”).

A fluoroolefin is an olefin in which one or more hydrogen atoms are substituted with fluorine atoms. In the fluoroolefin, one or more hydrogen atoms not substituted with fluorine atoms may be substituted with chlorine atoms.
Specific examples of the fluoroolefin include CF ₂ = CF ₂ , CF ₂ = CFCF ₃ , CF ₂ = CFCl, and CH ₂ = CF ₂ . Fluoroolefins cured film (hereinafter, also referred to as "cured film".) Which is formed from the coating material from the weather resistance of the point of view _of, CF 2 = CF ₂ and _CF 2 = CFCl are preferred.
Two or more fluoroolefins may be used in combination.
The content of the unit F is preferably 20 to 70 mol%, particularly preferably 40 to 60 mol%, based on all units contained in the fluoropolymer, from the viewpoint of the weather resistance of the cured film.

The first crosslinkable group possessed by the monomer C is a functional group (hydroxy group, carboxy group, amino group, etc.) having active hydrogen or a hydrolyzable silyl group (alkoxysilyl) from the viewpoint of curability of the cured film. Group, etc.) are preferred, a hydroxy group or a carboxy group is more preferred, and a hydroxy group is particularly preferred.
Specific examples of the monomer C include hydroxyalkyl vinyl ether, hydroxycycloalkyl vinyl ether, hydroxyalkyl vinyl ester, hydroxycycloalkyl vinyl ester, hydroxyalkyl allyl ether, hydroxyalkyl allyl ester, hydroxyalkyl acrylate, hydroxyalkyl methacrylate. Examples include esters. Among these, from the viewpoint of curability of the cured film, hydroxyalkyl vinyl ether and hydroxyalkyl allyl ether are preferable, and 4-hydroxybutyl vinyl ether and 2-hydroxyethyl allyl ether are more preferable.
Monomer C may use 2 or more types together.

The content of unit C is preferably 1 to 40 mol%, more preferably 5 to 15 mol%, based on the total units contained in the fluoropolymer, from the viewpoint of scratch resistance and contamination resistance of the cured film.

The fluorine-containing polymer of the present invention has an alkyl group having a tertiary carbon atom of 3 to 9 carbon atoms or 4 to 10 carbon atoms from the viewpoint of forming a cured film having a high Tg and excellent impact resistance. And a unit (hereinafter also referred to as “unit T”) based on a monomer having a cycloalkyl group in the side chain (hereinafter also referred to as “monomer T”). The monomer T contains neither a fluorine atom nor a crosslinkable group.
Specific examples of the alkyl group and the cycloalkyl group include a tert-butyl group, a neononyl group, a cyclohexyl group, a cyclohexylmethyl group, a 4-cyclohexylcyclohexyl group, and a 1-decahydronaphthyl group.
The monomer T is vinyl ether, allyl ether, vinyl ester, allyl ester, acrylic acid ester or methacrylic acid ester, and is an alkyl group having 3 to 9 carbon atoms or a cyclocarbon having 4 to 10 carbon atoms. Monomers having an alkyl group in the side chain are preferred.
Specific examples of the monomer T include cyclohexyl vinyl ether, tert-butyl vinyl ether, tert-butyl vinyl ester, and neononanoic acid vinyl ester.
The monomer T may use 2 or more types together.
The content of the unit T is preferably 10 to 45 mol%, more preferably 12 to 40 mol%, more preferably 15 to 40 mol% with respect to the total units contained in the fluoropolymer, from the viewpoint of adjusting the Tg of the fluoropolymer. 35 mol% or 36 to 40 mol% is particularly preferred, and 36 to 40 mol% is particularly preferred.

The fluoropolymer further includes units other than the units F, C and T (units based on monomers other than the monomer F, the monomer C and the monomer T. Hereinafter, also referred to as “unit H”) May be included).
Specific examples of monomers that can constitute the unit H include alkyl vinyl ethers (nonyl vinyl ether, hexyl vinyl ether, ethyl vinyl ether, n-butyl vinyl ether, etc.), alkyl allyl ethers (ethyl allyl ether, hexyl allyl ether, etc.), carboxylic acids Examples include vinyl esters (such as acetic acid, butyric acid, and propionic acid) and allyl esters of carboxylic acids (such as acetic acid, butyric acid, and propionic acid).
Two or more of these monomers may be used in combination.
The content of the unit H is preferably 50 mol% or less, more preferably 30 mol% or less, based on all units contained in the fluoropolymer.

In the fluoropolymer in the present invention, from the viewpoint of the weather resistance and scratch resistance of the cured film, the content of unit F, unit C, unit T, and unit H with respect to all units contained in the fluoropolymer, In this order, 20 to 70 mol%, 1 to 40 mol%, 10 to 45 mol%, and 0 to 50 mol% are preferable.
The Mn of the fluoropolymer is preferably 3,000 to 50,000, more preferably 5,000 to 30,000, and particularly preferably 5,000 to 20,000.
When the fluorinated polymer has a hydroxy group, the hydroxyl value of the fluorinated polymer is preferably from 1 to 150 mgKOH / g, more preferably from 1 to 100 mgKOH / g, particularly preferably from 15 to 50 mgKOH / g.
The fluorine content of the fluoropolymer is preferably 10 to 70% by mass, more preferably 20 to 60% by mass, and particularly preferably 20 to 30% by mass from the viewpoint of the stain resistance and weather resistance of the cured film. When the fluorine content of the fluoropolymer is 10% by mass or more, the weather resistance of the cured film is more excellent. When the fluorine content of the fluoropolymer is 70% by mass or less, the surface smoothness of the cured film is excellent.
The Tg of the fluoropolymer is preferably 35 ° C. or higher, more preferably 50 ° C. or higher, from the viewpoint of stain resistance of the cured film. The Tg of the fluoropolymer is preferably 150 ° C. or lower, more preferably 120 ° C. or lower, and particularly preferably 100 ° C. or lower.

The content of the fluoropolymer in the present paint is 20 to 80 with respect to the total amount of the fluoropolymer, polyrotaxane and curing agent of the paint of the present invention from the viewpoint of stain resistance and weather resistance of the cured film. % By mass is preferable, and 25 to 75% by mass is more preferable.
The ratio of the mass of the fluoropolymer to the mass of the polyrotaxane in this paint (the mass of the fluoropolymer / the mass of the polyrotaxane) has both the stain resistance and the scratch resistance of the cured film, and is also stretchable. From the viewpoint of superiority, it is preferably 1.5 or more, more preferably 2.0 to 90, and particularly preferably 3.0 to 30.

The polyrotaxane in the present invention is a crosslinkable polyrotaxane having a second crosslinkable group. The crosslinkable polyrotaxane may be directly cross-linked (bonded) with the fluoropolymer, or may be cross-linked with the fluoropolymer through a curing agent described later.
Polyrotaxane is a quasi-polyrotaxane in which openings of cyclic molecules such as cyclodextrin are skewered by linear shaft molecules, and multiple cyclic molecules enclose the shaft molecules (both ends of the shaft molecules). And a molecular complex in which a blocking group is arranged so that the cyclic molecule is not released. That is, the polyrotaxane has a cyclic molecule, a shaft molecule that includes the cyclic molecule in a skewered manner, and a blocking group that is disposed at both ends of the shaft molecule and prevents the removal of the cyclic molecule.
In addition, in this specification, in addition to the said molecular complex, a polyrotaxane includes the crosslinked body by which the said molecular complex was bridge | crosslinked by the cyclic molecule part. In the present specification, an embodiment in which a cyclic molecule such as cyclodextrin is modified to improve compatibility and solubility is also included in the polyrotaxane.

In polyrotaxane, the cyclic molecule can move freely on the axis molecule. Therefore, for example, when a cyclic molecule has a crosslinkable group, the crosslinkable group on the cyclic molecule moves with the free movement of the cyclic molecule, so that the cross-linked structure formed by the polyrotaxane is flexible against an applied impact. Can be dealt with. That is, the cross-linked structure can exhibit a force for correcting the disorder of the cross-linked structure caused by the impact without being destroyed by the impact (hereinafter, this effect is also referred to as “self-repairing”). Therefore, it is considered that the cured film is excellent in scratch resistance due to the excellent self-healing property of the crosslinked structure formed by the polyrotaxane, as well as the improved curability of the cured film due to the crosslinking between the polyrotaxane and the fluoropolymer.

The axial molecule constituting the polyrotaxane is not particularly limited as long as it is a linear molecule that is included in the cyclic molecule and can be integrated non-covalently with the cyclic molecule.
In addition, “linear” of the axial molecule that is linear means substantially “linear”. In other words, the axial molecule may have a branched chain as long as the cyclic molecule as a rotor is rotatable or the cyclic molecule is slidable on the axial molecule. Further, the length of the “straight chain” is not particularly limited as long as the cyclic molecule can slide or move on the axial molecule.

The Mw of the axial molecule is preferably 1,000 or more, more preferably 5,000 or more, and particularly preferably 10,000 or more. Further, the Mw of the axial molecule is preferably 100,000 or less, more preferably 50,000 or less, and particularly preferably 40,000 or less. If the Mw of the axial molecule contained in the polyrotaxane is 1,000 or more, the compatibility between the polyrotaxane and the fluoropolymer is excellent, and the curability of the cured film is improved, so that the scratch resistance of the cured film is further improved. Cheap. If the Mw of the axial molecule contained in the polyrotaxane is 100,000 or less, the fluoropolymers crosslinked via the polyrotaxane become dense, and the contamination resistance of the cured film is further improved.

The linear shaft molecules constituting the polyrotaxane include polycaprolactone, styrene-butadiene copolymer, isobutene-isoprene copolymer, polyisoprene, natural rubber, polyalkylene glycol, polyisobutylene, polybutadiene, polypropylene glycol, polytetrahydrofuran , Polydimethylsiloxane, polyethylene, polypropylene, ethylene-polypropylene copolymer, and the like. The axial molecules are preferably polyethylene glycol, polypropylene glycol, polytetrahydrofuran, polyethylene glycol-polypropylene glycol copolymer, polyisoprene, polyisobutylene, polybutadiene, polydimethylsiloxane, polyethylene and polypropylene. A particularly preferred axial molecule is polyethylene glycol.
Specific examples of the blocking group that blocks both ends of the axial molecule include dinitrophenyl group, adamantyl group, trityl group, fluorescein, and pyrene. For example, the terminal hydroxy group of polyethylene glycol can be converted to a carboxy group and reacted with 1-adamantanamine to block both ends of polyethylene glycol.

As the cyclic molecule constituting the polyrotaxane, any cyclic molecule can be used as long as it is a cyclic molecule that can include the axial molecule.
Specific examples of the cyclic molecule include cyclodextrin (α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, dimethylcyclodextrin, glucosylcyclodextrin, etc.), crown ether, benzocrown, dibenzocrown, dicyclohexanocrown. And derivatives thereof. As the cyclic molecule, cyclodextrin is particularly preferable.

The crosslinkable group possessed by the polyrotaxane may be possessed by a cyclic molecule, may be possessed by an axial molecule, or preferably possessed by a cyclic molecule.
When the cyclic molecule is a cyclodextrin, it has a hydroxy group, and this hydroxy group can be converted into another crosslinkable group. In addition, crown ether having a crosslinkable group or the like can also be used.
Since a polyrotaxane usually includes a plurality of cyclic molecules in one axial molecule, when the cyclic molecule has a crosslinkable group, the polyrotaxane has two or more crosslinkable groups. Moreover, also when it has a crosslinkable group in the blocking group of an axial molecule, since the blocking group exists in both ends of an axial molecule, the polyrotaxane has two or more crosslinking groups.

As the polyrotaxane having the second crosslinkable group, an ester-modified product or an ether-modified product obtained by ring-opening addition of a cyclic ester or a cyclic ether to a polyrotaxane having a cyclic molecule having a functional group such as a hydroxy group can also be used. . For example, a modified product obtained by ring-opening addition of a cyclic ester or a cyclic ether to the hydroxyl group of cyclodextrin, which is a cyclic molecule, is known (see, for example, JP-A-2007-91938). It can be used as a polyrotaxane having a crosslinkable group. In addition, the group produced | generated by ring-opening addition of cyclic ester and cyclic ether to the hydroxy group of cyclodextrin is a group which has a hydroxyl group at the terminal.
Examples of the cyclic ether include alkylene oxides such as ethylene oxide and propylene oxide. Examples of the cyclic ester include ε-caprolactone, γ-butyrolactone, and δ-valerolactone.

The second crosslinkable group in the polyrotaxane is preferably a hydroxy group and a carboxy group, and is preferably a hydroxy group from the viewpoint of crosslinkability with a curing agent.
When the crosslinkable group of the polyrotaxane is a hydroxy group, the hydroxyl value of the polyrotaxane is preferably 200 mgKOH / g or less, more preferably 10 to 200 mgKOH / g, and further preferably 50 to 150 mgKOH / g. 50 to 100 mgKOH / g is particularly preferable. When the hydroxyl value of the polyrotaxane is 10 mgKOH / g or more, the cured film has excellent scratch resistance, and when it is 200 mgKOH / g or less, the cured film has excellent water resistance.

The Tg of the polyrotaxane is preferably 0 ° C. or lower, more preferably 0 ° C. or lower and −60 ° C. or higher from the viewpoint of compatibility with the fluoropolymer.
The content of the polyrotaxane in the present paint is preferably 0.1 to 30% by mass with respect to the total amount of the fluoropolymer, the polyrotaxane and the curing agent in the present paint, from the viewpoint of scratch resistance of the present cured film. 20% by mass is more preferable, and 5 to 15% by mass is particularly preferable.

The curing agent in the present invention is a compound having two or more functional groups capable of reacting with both the first crosslinkable group and the second crosslinkable group. The number of functional groups in the curing agent is usually 30 or less.

Specific examples of curing agents include isocyanate curing agents, amine curing agents (melamine resins, guanamine resins, sulfoamide resins, urea resins, aniline resins, etc.), β-hydroxyalkylamide curing agents, epoxy curing agents ( Triglycidyl isocyanurate-based curing agents and the like) and carbodiimide-based curing agents. Two or more curing agents may be used in combination.
When the fluoropolymer has a hydroxy group and the polyrotaxane has a hydroxy group, the curing agent is preferably an isocyanate curing agent from the viewpoint of adhesion between the cured film and the substrate and curability of the paint. .
Specific examples of the isocyanate curing agent include a curing agent having two or more isocyanate groups and a curing agent having two or more blocked isocyanate groups (hereinafter, also referred to as “blocked isocyanate curing agent”). Is mentioned.

Specific examples of the former curing agent include alicyclic polyisocyanates such as isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (HMDI), methylcyclohexane diisocyanate, and bis (isocyanatomethyl) cyclohexane, hexa Examples thereof include aliphatic polyisocyanates such as methylene diisocyanate (HDI), dimer acid diisocyanate and lysine diisocyanate, and modified products (biuret, isocyanurate, adduct, etc.) of these compounds.
An adduct is a compound having an isocyanate group obtained by reacting a polyisocyanate with a low molecular weight compound having active hydrogen. Examples of the low molecular weight compound having active hydrogen include water, polyhydric alcohol, polyamine, and alkanolamine. Specific examples include ethylene glycol, propylene glycol, trimethylolpropane, glycerin, sorbitol, ethylenediamine, ethanolamine, and diethanolamine. As the low molecular weight compound having active hydrogen, a polyhydric alcohol is particularly preferable.
Among them, from the viewpoint of obtaining a cured film with less elasticity and less cracking, an adduct of the above compound is preferable, an adduct of aliphatic polyisocyanate is more preferable, and an adduct of HDI is particularly preferable.

The blocked isocyanate curing agent can be produced by reacting the polyisocyanate with a blocking agent.
Specific examples of blocking agents include alcohols (methanol, ethanol, benzyl alcohol, etc.), phenols (phenol, crezone, etc.), lactams (caprolactam, butyrolactam, etc.), oximes (cyclohexanone, oxime, methyl ethyl ketoxime, etc.) Can be mentioned.

The content of the curing agent is preferably 10 to 200 parts by mass, more preferably 30 to 170 parts by mass, and particularly preferably 50 to 150 parts by mass with respect to 100 parts by mass of the fluoropolymer in the paint. If content of a hardening | curing agent is in the said range, bridge | crosslinking with a fluoropolymer and a polyrotaxane will advance favorably.

The paint may contain a curing catalyst.
The curing catalyst is a compound that accelerates the curing reaction when the above-described curing agent is used, and can be selected from known curing catalysts according to the type of the curing agent. The content of the curing catalyst is preferably 0.00001 to 0.01 parts by mass with respect to 100 parts by mass of the curing agent.

This paint may contain components other than the above if necessary. Specific examples of components other than the above include dispersion media and solvents (water, organic solvents, etc.), ultraviolet absorbers, light stabilizers (hindered amine light stabilizers, etc.), matting agents (ultrafine powder synthetic silica, etc.), leveling agents, Surface conditioner, surfactant, degassing agent, plasticizer, filler, heat stabilizer, thickener, dispersant, antistatic agent, rust inhibitor, silane coupling agent, antifouling agent, low contamination treatment Agents.

This paint can be used as a solution type (ie, a paint containing a solvent capable of dissolving a fluoropolymer), a water dispersion type, or a powder type (ie, a powder paint substantially free of a solvent). A solution type is preferable, and a paint containing an organic solvent is more preferable.
In the powder type, the content of the solvent in the paint is 1% by mass or less, preferably 0.5% by mass or less, particularly preferably 0% by mass with respect to the total mass of the paint.

A well-known method can be adopted as a manufacturing method of this paint. The solution-type paint is produced, for example, by dissolving the above-described components in a solvent using a stirrer such as a disper. The powder-type paint is produced, for example, by melting and kneading a powdery mixture obtained by mixing each component in advance with an extruder, and crushing the extruded kneaded material after cooling.

The method for producing a vehicle interior member according to the present invention is a method in which a coating film is formed on a vehicle interior substrate by coating the coating material, and the coating film is cured to form a cured film. By this method, a vehicle interior member having a vehicle interior base material and a fully cured film disposed on the vehicle interior base material is obtained. Since the vehicle interior member obtained in this way has a fully cured film, it is excellent in scratch resistance and contamination resistance.
Specific examples of the vehicle interior member include a dashboard (instrument panel), a center console, a door trim, a center cluster, a switch panel, and a shift knob.

The present paint may be applied directly to the vehicle interior base material, or may be applied to a film used by being attached to the vehicle interior base material. In addition, when painting on the film used by sticking to the said vehicle interior base material, in the manufacturing method of the vehicle interior member of this invention, the film in which the cured film was formed will be affixed on the said vehicle interior base material. .

Specific examples of the material constituting the vehicle interior base material include polycarbonate resin, acrylic resin, methacrylic resin, acrylonitrile-butadiene-styrene copolymer, polystyrene, polypropylene, and polyester resin (polyethylene terephthalate, polybutylene terephthalate).
Specific examples of the material constituting the film include polycarbonate resin, acrylic resin, methacrylic resin, ABS resin, polyolefin resin (polyethylene, polypropylene, etc.), polyvinyl halide resin (polyvinyl chloride, polyvinylidene chloride, polyvinyl fluoride, Polyvinylidene fluoride, etc.), polyester resins (polyethylene terephthalate, polybutylene terephthalate, etc.), polyamide resins (nylon 6, nylon 66, MXD nylon (metaxylenediamine-adipic acid copolymer), etc.), weight of olefin having substituents And EVA (ethylene-vinyl alcohol copolymer), ethylene-tetrafluoroethylene copolymer, etc.). The film may use two or more of these materials in combination.

Specific examples of coating methods for this paint include sponge coating, spray coating, curtain coating (flow coating), roll coating, casting, dip coating, spin coating, die coating, electrostatic coating, static coating Examples thereof include an electrospraying method, an electrostatic dipping method, and a fluid dipping method.
Examples of the method for drying a coating film containing a solvent include natural drying, vacuum drying, centrifugal drying, heat drying, and the like, and heat drying is preferable from the viewpoint of serving also as a curing treatment described later.
The drying temperature of the coating film containing the solvent is preferably 15 to 45 ° C., more preferably 20 to 40 ° C. from the viewpoint of sufficiently volatilizing the solvent. The drying time is preferably 15 minutes to 14 days, more preferably 30 minutes to 10 days.
An example of the coating treatment method is a heat treatment. In this case, the heating temperature is preferably 40 ° C. to 200 ° C., more preferably 45 ° C. to 150 ° C., from the viewpoint that bubbles or the like hardly occur in the cured film. The heating time is preferably 1 minute to 3 hours, and more preferably 3 minutes to 2 hours.

The thickness of the cured film is preferably 5 to 150 μm, more preferably 10 to 100 μm. If the thickness of the cured film is 5 μm or more, the scratch resistance and stain resistance of the cured film are more exhibited, and if it is 150 μm or less, the vehicle interior member can be reduced in weight.

The vehicle interior member of the present invention has the vehicle interior base material and a cured film formed from the paint disposed on the vehicle interior base material. Since the vehicle interior member of the present invention has a cured film of the present paint, it is excellent in scratch resistance and contamination resistance. The vehicle interior member of the present invention can be manufactured, for example, by the above-described method for manufacturing a vehicle interior member.

Hereinafter, the present invention will be described in detail with examples. However, the present invention is not limited to these examples. In addition, the compounding quantity of each component in the table | surface mentioned later shows a mass reference | standard. Examples 1 to 3 and Examples 6 to 9 are examples, and examples 4 to 5 are comparative examples.

[Production Example of Fluoropolymer 1]
In an autoclave, cyclohexyl vinyl ether (CHVE) (51.2 g), 4-hydroxybutyl vinyl ether (HBVE) (13.3 g), xylene (55.8 g), ethanol (15.7 g), potassium carbonate (1.1 g), A 50% by mass xylene solution (0.7 g) of tert-butylperoxypivalate (PBPV) and chlorotrifluoroethylene (CTFE) (63 g) were introduced, and polymerization was performed at 65 ° C. for 15 hours with stirring. The solution in the autoclave was filtered, and the obtained filtrate was distilled off under reduced pressure to obtain a fluoropolymer 1.
The fluoropolymer 1 contains 50 mol%, 39 mol%, and 11 mol% of units based on CTFE, units based on CHVE, and units based on HBVE in this order with respect to all units contained in the fluoropolymer 1. It was a polymer.
Further, the fluoropolymer 1 had a Tg of 55 ° C., a fluorine content of 23.7% by mass, a hydroxyl value of 50 mgKOH / g, and Mn of 12,000.

[Production Example of Fluoropolymer 2]
The monomer and ethyl vinyl ether (EVE) used in Production Example of Fluoropolymer 1 were used, and the amount of each monomer was adjusted to be similar to that in Production Example of Fluoropolymer 1 and contained. Fluoropolymer 2 was obtained. The fluoropolymer 2 is composed of units based on CTFE, units based on CHVE, units based on HBVE, and units based on EVE in this order of 50 mol% and 15 mol% with respect to all units contained in the fluoropolymer 2. The polymer contained 10 mol% and 25 mol%.
Fluoropolymer 2 had a Tg of 37 ° C., a fluorine content of 26.7% by mass, a hydroxyl value of 53 mgKOH / g, and Mn of 20,000.

[Manufacture of paint]
The components shown in Table 1 were mixed so that the blending amounts (parts by mass) shown in Table 1 described later were obtained, and paints of Examples 1 to 9 were obtained. Below, the outline | summary of each component is shown.

<Fluoropolymer solution>
The fluoropolymer solution 1 is a solution in which the fluoropolymer 1 is dissolved in butyl acetate. In addition, the numerical value in the parenthesis in Table 1 indicates the amount (part by mass) of the fluoropolymer 1 contained in the fluoropolymer solution.
-The fluoropolymer solution 2 is a solution in which the fluoropolymer 2 is dissolved in butyl acetate. In addition, the numerical value in the parenthesis in Table 1 indicates the amount (part by mass) of the fluoropolymer 2 contained in the fluoropolymer solution.
<Polyrotaxane>
Serum superpolymer SH2400P (manufactured by Advanced Soft Materials Co., Ltd., polyrotaxane having a hydroxyl group, axial molecular Mw: 20,000, hydroxyl value: 76 mgKOH / g, Tg: −50 ° C.) This polyrotaxane is a polyrotaxane obtained by modifying a polyrotaxane having a cyclodextrin as a cyclic molecule and a polyethylene glycol chain having an adamantyl group as a blocking group as an axis molecule with propylene oxide and ε-caprolactone (Japanese Patent Laid-Open No. 2007-91938). (See the examples in the publication number).
<Polycarbonate polyol>
・ Duranol T-5650E (manufactured by Asahi Kasei Co., Ltd., Mn: 500, hydroxyl value: 200 mg KOH / g, Tg: −50 ° C. or less)
<Curing agent>
Curing agent 1: Coronate HX (manufactured by Nippon Polyurethane Co., Ltd., isocyanurate-modified HDI type polyisocyanate curing agent, solid content 100% by mass)
Curing agent 2: Duranate E405-70B (manufactured by Asahi Kasei Corporation, butyl acetate solution of HDI adduct type polyisocyanate curing agent, solid content 70% by mass). The numerical values in parentheses in Table 1 indicate the solid content (parts by mass) of E405-70B.
<Curing catalyst>
DBTDL solution: Dibutyltin dilaurate solution in butyl acetate (diluted 10,000 times). In addition, the numerical value in the bracket | parenthesis in Table 1 shows the solid content amount (mass part) of a DBTDL solution.

[Evaluation test]
<Preparation of test piece>
Each paint is applied on an acrylic resin film with a bar coater to form a coating film, and then heated and dried at 25 ° C. for 30 minutes and heat-treated at 80 ° C. for 10 minutes to form the paint on the film. A test piece having a cured film (film thickness 50 μm) was obtained.
Using the obtained test piece, evaluation was performed as follows.

<Contamination resistance (sun oil resistance)>
On the cured film of the test piece, 1 drop (0.005 g) of sunscreen (copatone water babes lotion SPF50) was dropped and extended with a brush in the range of 2 cm × 3 cm, and then 5 sheets of gauze were added. And left at 80 ° C. for 1 hour. Thereafter, the sunscreen agent was wiped off with gauze, the test piece was washed with water, and changes in the cured film were observed visually. The evaluation criteria are as follows.
A: No change is observed in the cured film.
B: Minute coating marks are observed on the cured film.
C: The surface of the cured film is severely deteriorated and the coating mark is clearly recognized.

<Scratch resistance 1>
Using steel wool (# 0000), the surface of the cured film of the test piece was rubbed 15 times with a load of 200 g, and then the surface was visually observed and evaluated according to the following criteria.
A: There was no scratch.
B: Scratches are slightly observed and less than 20% with respect to the area of the test piece.
C: Many scratches are observed, which is 20% or more with respect to the area of the test piece.

<Scratch resistance 2>
Using steel wool (# 0000), the surface of the cured film of the test piece was rubbed 15 times with a load of 300 g, and then the surface was visually observed and evaluated according to the following criteria.
A: There was no scratch.
B: Scratches are slightly observed and less than 20% with respect to the area of the test piece.
C: Many scratches are observed, which is 20% or more with respect to the area of the test piece.

<Elongation>
Using autograph AGS10KNG (manufactured by Shimadzu Corporation), TERMOSATATIC CHAMBER Model: TCRI-200SP (manufactured by Shimadzu Corporation), the test piece size is 10 mm × 100 mm, the chuck is 50 mm, the pulling speed is 50 mm / min, and the temperature of the tension thermostat is 23 ° When a tensile test was performed under the conditions, the elongation rate of the test piece until a crack occurred in the cured film was visually confirmed.
S: The elongation of the test piece is 150% or more with respect to the test piece before the tensile test.
A: The elongation of the test piece is 100% or more and less than 150% with respect to the test piece before the tensile test.
B: The elongation of the test piece is 50% or more and less than 100% with respect to the test piece before the tensile test.
C: The elongation of the test piece is less than 50% with respect to the test piece before the tensile test.

<Evaluation results>
The results of the above evaluation tests are shown in Table 1.

As shown in Table 1, it was shown that a cured film formed from a paint containing a fluoropolymer and a polyrotaxane was excellent in scratch resistance and stain resistance against sunscreen agents.
In addition, the coating composition produced in Examples 1 to 3 described above was applied on the dashboard (instrument panel), center console, door trim, center cluster, switch panel, or shift knob to form a cured film. In any case, the scratch resistance and stain resistance were excellent.
The entire contents of the specification, claims and abstract of Japanese Patent Application No. 2017-049467 filed on Mar. 15, 2017 are incorporated herein as the disclosure of the specification of the present invention. It is.

Claims

A fluoropolymer comprising units based on a fluoroolefin and units based on a monomer having a first crosslinkable group;
A polyrotaxane having two or more second crosslinkable groups;
And a curing agent having two or more functional groups capable of reacting with at least one of the first crosslinkable group and the second crosslinkable group.
The paint according to claim 1, wherein the glass transition temperature of the fluoropolymer is 50 ° C or higher.
The fluorine-containing polymer further includes a unit based on a monomer having an alkyl group having a tertiary carbon atom having 3 to 9 carbon atoms or a cycloalkyl group having 4 to 10 carbon atoms in the side chain, The paint according to claim 1 or 2, wherein the content is 10 to 45 mol% with respect to all units contained in the fluoropolymer.
The content of units based on the monomer having the first crosslinkable group is 1 to 40 mol% with respect to all units contained in the fluoropolymer. The paint described in 1.
The paint according to any one of claims 1 to 4, wherein the first crosslinkable group is a hydroxy group, and the hydroxyl value of the fluoropolymer is 1 to 150 mgKOH / g.
The paint according to any one of claims 1 to 5, wherein a ratio of a mass of the fluoropolymer to a mass of the polyrotaxane is 1.5 or more.
The paint according to any one of claims 1 to 6, wherein the polyrotaxane has a glass transition temperature of 0 ° C or lower.
The polyrotaxane is a polyrotaxane having a cyclodextrin as a cyclic molecule and a polyethylene glycol having both ends blocked with blocking groups as an axis molecule, or a cyclic ester-modified product or a cyclic ether-modified product of the polyrotaxane. The paint according to any one of the above.
The paint according to any one of claims 1 to 8, wherein the second crosslinkable group is a hydroxy group or a carboxy group.
The coating material according to claim 9, wherein the second crosslinkable group is a hydroxy group, and the polyrotaxane has a hydroxyl value of 200 mgKOH / g or less.
The paint according to any one of claims 1 to 10, wherein the polyrotaxane has an axial molecular weight average molecular weight of 1,000 or more.
The paint according to any one of claims 1 to 11, wherein the content of the polyrotaxane is 0.1 to 30% by mass with respect to the total amount of the fluoropolymer, the polyrotaxane and the curing agent.
The paint according to any one of claims 1 to 12, wherein the first crosslinkable group and the second crosslinkable group are both hydroxy groups, and the curing agent is an isocyanate curing agent.
A vehicle interior member having a vehicle interior base material and a cured film formed from the paint according to any one of claims 1 to 13 disposed on the vehicle interior base material.
A method for manufacturing a vehicle interior member, comprising: applying a coating material according to any one of claims 1 to 13 to form a coating film on a vehicle interior substrate; and curing the coating film to form a cured film. .