WO2021131429A1 - Surface treatment layer and article - Google Patents

Abstract

The present invention addresses the problem of providing a surface treatment layer which uses a material that contains water, and which is suppressed in gloss change during drawing, while having excellent peel strength and ethanol resistance. A surface treatment layer which comprises a primer layer (i) and a top coat layer (ii), and which is characterized in that: the primer layer (i) is formed from a resin composition for primer layer formation, said composition containing a urethane resin (A), an olefin resin (B), a filler (C) and water (D); the gloss value of the primer layer (i) is less than 0.9; the top coat layer (ii) is formed from a resin composition for top coat layer formation, said composition containing a urethane resin (X), beads (Y) and water (Z); and the filling rate of the beads in the top coat layer (ii) is within the range of from 25% to 90%.

Description

Surface treatment layer and articles

The present invention relates to a surface treatment layer and an article.

In the manufacturing process of seats for automobile interior thermoplastic olefin resin (TPO) leather, the surface is finished with a surface treatment agent from the viewpoint of imparting durability and design. The mainstream materials used for conventional surface treatment agents are solvent-based resin compositions containing organic solvents, but due to the recent increase in environmental regulations, aqueous surface treatment agents that do not substantially contain organic solvents. Development is in progress.

Furthermore, with the diversification of design as an automobile, there is a growing demand for a finish that emphasizes design in the shape of the instrument panel and door trim. However, with the current water-based surface treatment agent (see, for example, Patent Document 1), when molded into a shape designed by a designer of an automobile manufacturer, a portion that is locally highly stretched occurs at the end of the molded product. , Only that part becomes glossy, and the design (design) is impaired. In addition to this, the market strongly demands improvement of peel strength against TPO leather and ethanol resistance of the surface treatment layer.

Japanese Unexamined Patent Publication No. 2006-176615

An object to be solved by the present invention is to provide a surface treatment layer which uses a water-containing material, has little change in gloss during stretching, and has excellent peel strength and ethanol resistance.

The present invention is a surface treatment layer having a primer layer (i) and a top coat layer (ii), and the primer layer (i) is a urethane resin (A), an olefin resin (B), and a filler (C). ) And the resin composition for forming a primer layer containing water (D), the primer layer (i) has a gloss value of less than 0.9, and the top coat layer (ii). ) Is formed from a resin composition for forming a topcoat layer containing urethane resin (X), beads (Y), and water (Z), and the beads (ii) in the topcoat layer (ii). It provides a surface treatment layer characterized in that the filling rate of Y) is in the range of 25 to 90%.

The present invention also provides an article characterized by having a thermoplastic olefin resin base material and the surface-treated layer.

Since the surface treatment layer of the present invention uses a material containing water, it is environmentally friendly, has little change in gloss during stretching, and has excellent peel strength and ethanol resistance. In particular, the surface-treated layer of the present invention has excellent peel strength against TPO leather.

The surface treatment layer of the present invention has a primer layer (i) and a top coat layer (ii), and it is essential that each layer is formed of a specific material.

The primer layer (i) may contain a urethane resin (A) and an olefin resin (B) in order to obtain excellent adhesion (peeling strength) to TPO leather and ethanol resistance. It is essential, and in order to suppress the change in gloss during stretching of the surface treatment layer, it contains a filler (C) which is a matting agent, and the filler (C) further reduces the gloss value of the primer layer (i) to 0. It is essential that it is less than 9.

The urethane resin (A) can be dispersed in water (D), and is, for example, a urethane resin having a hydrophilic group such as an anionic group, a cationic group, or a nonionic group; forcibly water (with an emulsifier). B) Urethane resin or the like dispersed therein can be used. These urethane resins (A) may be used alone or in combination of two or more.

Examples of the method for obtaining the urethane resin having an anionic group include a method using one or more compounds selected from the group consisting of a compound having a carboxyl group and a compound having a sulfonyl group as a raw material.

Examples of the compound having a carboxyl group include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2-dimethylolbutyric acid, 2,2-dimethylolpropionic acid, and 2,2-valeric acid. Valeric acid and the like can be used. These compounds may be used alone or in combination of two or more.

Examples of the compound having a sulfonyl group include 3,4-diaminobutanesulfonic acid, 3,6-diamino-2-toluenesulfonic acid, 2,6-diaminobenzenesulfonic acid, and N- (2-aminoethyl)-. 2-Aminoethyl sulfonic acid and the like can be used. These compounds may be used alone or in combination of two or more.

The carboxyl group and the sulfonyl group may be partially or completely neutralized with a basic compound in the resin composition. As the basic compound, for example, organic amines such as ammonia, triethylamine, pyridine, and morpholine; alkanolamines such as monoethanolamine and dimethylethanolamine; and metal base compounds containing sodium, potassium, lithium, calcium and the like are used. Can be done.

Examples of the method for obtaining the urethane resin having a cationic group include a method using one or more compounds having an amino group as a raw material.

Examples of the compound having an amino group include compounds having primary and secondary amino groups such as triethylenetetramine and diethylenetriamine; N-alkyldialkanolamines such as N-methyldiethanolamine and N-ethyldiethanolamine, and N-methyl. Compounds having a tertiary amino group such as N-alkyldiaminoalkylamine such as diaminoethylamine and N-ethyldiaminoethylamine can be used. These compounds may be used alone or in combination of two or more.

Examples of the method for obtaining the urethane resin having a nonionic group include a method using one or more compounds having an oxyethylene structure as a raw material.

As the compound having an oxyethylene structure, for example, a polyether polyol having an oxyethylene structure such as polyoxyethylene glycol, polyoxyethylene polyoxypropylene glycol, and polyoxyethylene polyoxytetramethylene glycol can be used. These compounds may be used alone or in combination of two or more.

The amount of raw materials used to produce the urethane resin having the above hydrophilic groups includes even better adhesion to TPO leather, suppression of gloss change during stretching, chemical resistance, abrasion resistance, and weather resistance. From the viewpoint of obtaining hydrolysis resistance, the range is preferably 0.1 to 15% by mass, more preferably 1 to 10% by mass, and 1.5% by mass in the raw material of the urethane resin (A). The range of ~ 7% by mass is more preferable.

Examples of the emulsifier that can be used to obtain the urethane resin that is forcibly dispersed in water (D) include polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene styrylphenyl ether, and polyoxy. Nonionic emulsifiers such as ethylene sorbitol tetraoleate and polyoxyethylene / polyoxypropylene copolymer; fatty acid salts such as sodium oleate, alkyl sulfates, alkylbenzene sulfates, alkyl sulfosuccinates, naphthalence sulfone, Anionic emulsifiers such as polyoxyethylene alkyl sulfate, alkansulfonate sodium salt, and alkyldiphenyl ether sulfonate sodium salt; cationic emulsifiers such as alkylamine salt, alkyltrimethylammonium salt, and alkyldimethylbenzylammonium salt can be used. it can. These emulsifiers may be used alone or in combination of two or more.

Specific examples of the urethane resin (A) include a raw material used for producing the urethane resin having a hydrophilic group, a polyisocyanate (a1), a polyol (a2), and a chain extender (a2). The reactant of a3) can be used. Known urethanization reactions can be used for these reactions.

Examples of the polyisocyanate (a1) include aromatic polyisocyanates such as phenylenediocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, naphthalene diisocyanate, polymethylene polyphenyl polyisocyanate, and carbodiimidated diphenylmethane polyisocyanate; hexamethylene diisocyanate. , Lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, dimerate diisocyanate, norbornene diisocyanate and other aliphatic or alicyclic polyisocyanates can be used. These polyisocyanates may be used alone or in combination of two or more.

As the polyisocyanate (a1), an alicyclic polyisocyanate can be obtained from the viewpoints of further excellent adhesion to TPO leather, suppression of gloss change during stretching, chemical resistance, abrasion resistance, and weather resistance. It is preferable to use polyisocyanate having at least one structure in which the nitrogen atom of the isocyanate group is directly linked to the cyclohexane ring, and it is further preferable to use isophorone diisocyanate and / or dicyclohexylmethane diisocyanate. The amount of the alicyclic polyisocyanate used is preferably 30% by mass or more in the polyisocyanate (a1) from the viewpoint of obtaining even more excellent chemical resistance, abrasion resistance, and weather resistance. , 40% by mass or more is more preferable, and 50% by mass or more is further preferable.

When the surface treatment layer of the present invention is required to have even higher light resistance, it is preferable to use the alicyclic polyisocyanate and the aliphatic polyisocyanate together as the polyisocyanate (a1). Hexamethylene diisocyanate is preferably used as the aliphatic polyisocyanate. At this time, the content of the alicyclic polyisocyanate in the polyisocyanate (a1) is preferably 30% by mass or more, more preferably 40% by mass or more, still more preferably 50% by mass or more.

As for the amount of the polyisocyanate (a1) used, the urethane resin can be obtained from the viewpoints of further excellent adhesion to TPO leather, suppression of gloss change during stretching, chemical resistance, abrasion resistance, and weather resistance. It is preferably in the range of 5 to 50% by mass, more preferably 15 to 40% by mass, and even more preferably 20 to 37% by mass in the raw material of (A).

As the polyol (a2), for example, a polyether polyol, a polyester polyol, a polyacrylic polyol, a polycarbonate polyol, a polybutadiene polyol, or the like can be used. These polyols may be used alone or in combination of two or more. Among these, it is preferable to use a polycarbonate polyol from the viewpoints of obtaining even more excellent adhesion to TPO leather, suppression of gloss change during stretching, chemical resistance, abrasion resistance, and weather resistance.

As the polycarbonate polyol, for example, a reaction product of a carbonic acid ester and / or phosgene and a compound having two or more hydroxyl groups can be used.

As the carbonic acid ester, for example, dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, propylene carbonate and the like can be used. These compounds may be used alone or in combination of two or more.

Examples of the compound having two or more hydroxyl groups include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, and 2-methyl. -1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,5-hexanediol, 3-methyl-1,5-pentanediol, 1,7-heptanediol , 1,8-octanediol, 1,9-nonanediol, 1,8-nonanediol, 2-ethyl-2-butyl-1,3-propanediol, 1,10-decanediol, 1,12-dodecanediol , 1,4-Cyclohexanedimethanol, 1,3-cyclohexanedimethanol, trimethylolpropane, 3-methylpentanediol, neopentyl glycol, trimethylolethane, glycerin and the like can be used. These compounds may be used alone or in combination of two or more. Among these, 1,3-propanediol and 1,4 are obtained from the viewpoints of further excellent adhesion to TPO leather, chemical resistance, suppression of gloss change during stretching, abrasion resistance, and weather resistance. One or more selected from the group consisting of -butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, 3-methylpentanediol, and 1,10-decanediol. It is preferable to use a compound, and 1,6-hexanediol is more preferable.

The amount of the polycarbonate polyol used in the polyol (a2) is such that even more excellent adhesion to TPO leather, suppression of gloss change during stretching, chemical resistance, abrasion resistance, and weather resistance can be obtained. It is preferably 85% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more.

As the number average molecular weight of the polycarbonate polyol, it is possible to obtain even more excellent adhesion to TPO leather, suppression of gloss change during stretching, chemical resistance, mechanical strength, abrasion resistance, and weather resistance. It is preferably in the range of 100 to 100,000, more preferably in the range of 150 to 10,000, and even more preferably in the range of 200 to 2,500. The number average molecular weight of the polycarbonate polyol shows a value measured by a gel permeation column chromatography (GPC) method.

The number average molecular weight of the polyol (a2) other than the polycarbonate polyol is 500 to 100,000 from the viewpoints of obtaining even more excellent adhesion to TPO leather, suppression of gloss change during stretching, and weather resistance. The range is preferably in the range of 700 to 50,000, more preferably in the range of 800 to 10,000. The number average molecular weight of the polyol (a2) indicates a value measured by a gel permeation column chromatography (GPC) method.

The amount of the polyol (a2) used is preferably in the range of 30 to 80% by mass, more preferably in the range of 40 to 75% by mass, and in the range of 50 to 70% by mass in the raw material of the urethane resin (A). Is more preferable.

The chain extender (a3) has, for example, a chain extender having a number average molecular weight in the range of 50 to 450 (excluding the polycarbonate polyol), and specifically, ethylenediamine, 1,2-propanediamine, 1, 6-Hexamethylenediamine, piperazine, 2,5-dimethylpiperazin, isophoronediamine, 1,2-cyclohexanediamine, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine, 4,4'-dicyclohexylmethanediamine, 3, Chain extender having an amino group such as 3'-dimethyl-4,4'-dicyclohexylmethanediamine, 1,4-cyclohexanediamine, hydrazine; ethylene glycol, diethylene recall, triethylene glycol, propylene glycol, dipropylene glycol, 1 , 3-Propanediol, 1,3-Butanediol, 1,4-Butanediol, Hexamethylene glycol, Saccharose, Methylene glycol, Glycerin, Sorbitol, Bisphenol A, 4,4'-dihydroxydiphenyl, 4,4'-Dihydroxy A chain extender having a hydroxyl group such as diphenyl ether or trimethylolpropane can be used. These chain extenders may be used alone or in combination of two or more.

As the chain extender (a3), even more excellent adhesion to TPO leather, suppression of gloss change during stretching, chemical resistance, mechanical strength, abrasion resistance, and weather resistance can be obtained. From this point of view, it is preferable to use a chain extender having an amino group, more preferably piperazine and / or hydrazine, and the total amount of piperazine and hydrazine is 30% by mass or more in the chain extender (a3). Is more preferable, 50% by mass or more is more preferable, 60% by mass or more is further preferable, and 80% by mass or more is particularly preferable. The chain extender (a3) preferably has an average number of functional groups of less than 3, more preferably less than 2.5. Also,

As the amount of the chain extender (a3) used, even more excellent adhesion to TPO leather, suppression of gloss change during stretching, chemical resistance, mechanical strength, abrasion resistance, and weather resistance can be obtained. From the point of view, it is preferably in the range of 0.5 to 10% by mass, more preferably in the range of 0.7 to 5% by mass, and further in the range of 0.9 to 2.3 in the raw material of the urethane resin (A). preferable.

As a method for producing the urethane resin (A), for example, the polyisocyanate (a1), the polyol (a2), and the raw material used for producing the urethane resin having a hydrophilic group are reacted to form an isocyanate group. A method of producing a urethane prepolymer having the above, and then reacting the urethane prepolymer with the chain extender (a3); the polyisocyanate (a1), the polyol (a2), and a hydrophilic group. Examples thereof include a raw material used for producing the urethane resin having the above, and a method in which the chain extender (a3) is collectively charged and reacted. These reactions may be carried out, for example, at 50 to 100 ° C. for 3 to 10 hours.

The total of the hydroxyl group of the raw material used for producing the urethane resin having a hydrophilic group, the hydroxyl group of the polyol (a2), the hydroxyl group and the amino group of the chain extender (a3), and the polyisocyanate. The molar ratio of (a1) to the isocyanate group [(isocyanate group) / (hydroxyl group and amino group)] is preferably in the range of 0.8 to 1.2, preferably 0.9 to 1.1. More preferably, it is in the range.

When producing the urethane resin (A), it is preferable to inactivate the isocyanate groups remaining in the urethane resin (A). When inactivating the isocyanate group, it is preferable to use an alcohol having one hydroxyl group such as methanol. The amount of the alcohol used is preferably in the range of 0.001 to 10 parts by mass with respect to 100 parts by mass of the urethane resin (A).

Further, when producing the urethane resin (A), an organic solvent may be used. Examples of the organic solvent include ketone compounds such as acetone and methyl ethyl ketone; ether compounds such as tetrahydrofuran and dioxane; acetate compounds such as ethyl acetate and butyl acetate; nitrile compounds such as acetonitrile; dimethylformamide, N-methylpyrrolidone and the like. An amide compound or the like can be used. These organic solvents may be used alone or in combination of two or more. It is preferable that the organic solvent is finally removed by a distillation method or the like.

The urethane bond content of the urethane resin (A) is such that even better adhesion to TPO leather, suppression of gloss change during stretching, chemical resistance, abrasion resistance, and weather resistance can be obtained. , 980 to 4,000 mmol / kg, more preferably 1,000 to 3,500 mmol / kg, even more preferably 1,100 to 3,000 mmol / kg, 1,150 to 2,500 mmol. The range of / kg. The urethane bond content of the urethane resin (A) includes the polyisocyanate (a1), the polyol (a2), the raw material used for producing the urethane resin having a hydrophilic group, and the chain extender (a3). ) Indicates the value calculated from the charged amount.

The urea bond content of the urethane resin (A) is such that even better adhesion to TPO leather, suppression of gloss change during stretching, chemical resistance, abrasion resistance, and weather resistance can be obtained. The range is preferably in the range of 315 to 850 mmol / kg, more preferably in the range of 350 to 830 mmol / kg, further preferably in the range of 400 to 800 mmol / kg, still more preferably in the range of 410 to 770 mmol / kg. The urea bond content of the urethane resin (A) includes the polyisocyanate (a1), the polyol (a2), the raw material used for producing the urethane resin having a hydrophilic group, and the chain extender. The value calculated from the charge amount of (a3) is shown.

As the content of the alicyclic structure of the urethane resin (A), further excellent adhesion to TPO leather, suppression of gloss change during stretching, chemical resistance, abrasion resistance, and weather resistance can be obtained. Therefore, it is preferably in the range of 500 to 3,000 mmol / kg, more preferably in the range of 600 to 2,900 mmol / kg, and even more preferably in the range of 700 to 2,700 mmol / kg. The content of the alicyclic structure of the urethane resin (A) includes the polyisocyanate (a1), the polyol (a2), the raw material used for producing the urethane resin having a hydrophilic group, and the chain extension. The value calculated from the charge amount of the agent (a3) is shown.

The content (solid content) of the urethane resin (A) is 6 to 30% by mass in the resin composition for forming a primer layer from the viewpoint of adhesion to TPO leather, coatability, workability and storage stability. The range is preferably in the range of 8 to 25% by mass, and more preferably in the range of 8 to 25% by mass.

As the olefin resin (B), for example, a polyolefin obtained by polymerizing a polyolefin compound; a natural rubber, an ethylene-vinyl acetate copolymer, a synthetic isopropylene rubber; or a modified product thereof can be used. These olefin resins may be used alone or in combination of two or more.

As the polyolefin compound, for example, ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene and the like can be used. Further, these olefin compounds may be used alone or in combination of two or more. The polyolefin may be a homopolymer or a copolymer.

As the modified product of the polyolefin, for example, a polyolefin modified with a hydroxyl group, an acid-modified polyolefin, a polyolefin modified with an amino group, or the like can be used. These polyolefins may be used alone or in combination of two or more. Among these, it is preferable to use acid-modified polyolefin because the adhesion to TPO leather can be further improved.

As the acid-modified polyolefin, for example, an acid-modified polyolefin without chlorination can be used. For the acid denaturation, a method of reacting with a polyolefin using an unsaturated carboxylic acid or an anhydride thereof is preferable. Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid, aconitic acid, crotonic acid; their anhydrides and the like; half ester of unsaturated carboxylic acid. , Halfamide and the like can be used. These compounds may be used alone or in combination of two or more. Among these, it is preferable to use one or more selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, and maleic anhydride.

Further, as the acid-modified polyolefin, one having a polyether chain is preferably used from the viewpoint of excellent dispersibility in water, and the polyether chain is a polyethylene chain and / or polypropylene. Chains are preferred, polyethylene chains are more preferred.

The weight average molecular weight of the olefin resin (B) is preferably in the range of 10,000 to 500,000 from the viewpoint of obtaining even more excellent adhesion to TPO leather and ethanol resistance. The range of 20,000 to 200,000 is more preferable. The weight average molecular weight of the olefin resin (B) indicates a value measured by a gel permeation column chromatography (GPC) method.

The content (solid content) of the olefin resin (B) is 0.5 to 0.5 in the primer layer forming resin composition from the viewpoint of obtaining even more excellent adhesion to TPO leather and ethanol resistance. The range is preferably in the range of 30% by mass, more preferably in the range of 0.6 to 25% by mass.

Further, as the mass ratio (solid content ratio) [(A) / (B)] of the urethane resin (A) and the olefin resin (B), the adhesion to the TPO leather and the resistance to the leather are even better. From the viewpoint of obtaining ethanolity, the range of 55/45 to 98/2 is preferable, and the range of 70/30 to 97/3 is more preferable.

Examples of the filler (C) include silica particles, organic beads, calcium carbonate, magnesium carbonate, barium carbonate, talc, aluminum hydroxide, calcium sulfate, kaolin, mica, asbestos, mica, calcium silicate, alumina silicate and the like. Can be used. These fillers may be used alone or in combination of two or more.

As the silica particles, for example, dry silica, wet silica and the like can be used. Among these, dry silica is preferable because it has a high scattering effect and a wide range of adjusting the gloss value. The average particle size of these silica particles is preferably in the range of 2 to 14 μm, more preferably in the range of 3 to 12 μm. The average particle size of the silica particles indicates the particle size (particle size at D50 in the particle size distribution) when the integrated amount occupies 50% in the integrated particle amount curve of the particle size distribution measurement result.

As the organic beads, for example, acrylic beads, urethane beads, silicon beads, olefin beads and the like can be used.

The content of the filler (C) is 1.5 to 10% by mass in the resin composition for forming the primer layer from the viewpoint that the gloss value of the primer layer (i) can be easily adjusted within the range specified in the present invention. The range is preferable, and the range of 2.5 to 6% by mass is more preferable.

As the water (D), ion-exchanged water, distilled water, or the like can be used. The content of the water (D) is preferably in the range of 1 to 60% by mass in the resin composition for forming a primer layer from the viewpoint of coatability, workability and storage stability, and is preferably 10 to 50% by mass. The% range is more preferred.

The resin composition for forming a primer layer contains the urethane resin (A), the olefin resin (B), the filler (C), and the water (D) as essential components, but if necessary, Other additives may be contained.

Examples of the other additives include a cross-linking agent (E), an emulsifier, a defoaming agent, a leveling agent, a thickener, a viscoelasticity adjusting agent, a wetting agent, a dispersant, a preservative, a plasticizer, a penetrant, and a fragrance. , Bactericides, acaricides, antifungal agents, ultraviolet absorbers, antioxidants, antistatic agents, flame retardants, dyes, pigments, auxiliary solvents and the like can be used. These additives may be used alone or in combination of two or more.

The cross-linking agent (E) is used for improving chemical resistance, abrasion resistance and peel strength. For example, a polyisocyanate cross-linking agent, an oxazoline cross-linking agent, a carbodiimide cross-linking agent, an epoxy cross-linking agent, and a melamine cross-linking agent Agents and the like can be used. These cross-linking agents may be used alone or in combination of two or more. Among these, it is preferable to use a carbodiimide cross-linking agent from the viewpoint of further improving chemical resistance and peel strength.

When the cross-linking agent (E) is used, the amount used is preferably in the range of 0.1 to 5% by mass (as a solid content) in the resin composition for forming the primer layer, and is preferably in the range of 0.3 to 3% by mass. More preferred.

The gloss value of the primer layer (i) is indispensable to be less than 0.9 from the viewpoint of suppressing the change in gloss during stretching of the surface treatment layer, and is more preferably in the range of 0.3 to 0.8. When the gloss value is within this range, the primer layer reflects diffusely even if the thickness of the top coat becomes thin and the transmitted light increases when the surface treatment layer is stretched, so that the gloss change during the stretching of the surface treatment layer can be suppressed. Inferred.

The topcoat layer (ii) contains urethane resin (X) and beads (Y) because of its excellent ethanol resistance and the ability to suppress changes in gloss during stretching of the surface treatment layer, and further, the topcoat layer (ii). It is essential that the filling rate of the beads (Y) in the layer (ii) is in the range of 25 to 90%.

As the urethane resin (X), the same urethane resin (A) as the urethane resin (A) used for the primer layer (i) can be used, and even better adhesion to TPO leather and affinity can be obtained. From this point of view, it is preferable that the urethane resins (A) and (X) are made of the same material.

The content (solid content) of the urethane resin (X) is a top coat layer from the viewpoints of adhesion to TPO leather, suppression of gloss change during surface treatment layer stretching, coatability, workability and storage stability. It is preferably in the range of 6 to 25% by mass, and more preferably in the range of 10 to 20% by mass in the resin composition for forming.

As the beads (Y), for example, acrylic beads, urethane beads, acrylic urethane beads, silicon beads, olefin beads and the like can be used. These organic beads may be used alone or in combination of two or more. Among these, it is preferable to use one or more selected from the group consisting of acrylic beads, urethane beads, and acrylic urethane beads from the viewpoint that even more excellent suppression of gloss change during stretching of the surface treatment layer can be obtained.

The average particle size of the beads (Y) is preferably 7 μm or more, more preferably 8 to 15 μm, from the viewpoint of obtaining even more excellent suppression of gloss change during stretching of the surface treatment layer. The average particle size of the beads (Y) is defined as the diameter of a circle equal to the projected area of each of the 100 particles existing in a certain area by observing the beads (Y) with a scanning electron microscope. It is calculated by the method of obtaining it and then averaging it.

As the content of the beads (Y), it is preferable that the filling rate of the beads (Y) in the top coat layer (ii) is more excellent because the gloss change can be suppressed at the time of stretching the surface treatment layer. From the viewpoint of easy adjustment to the range, the range is preferably 1.5 to 30% by mass, more preferably 2 to 25% by mass in the resin composition for forming the top coat layer.

As the water (Z), the same water (D) as that used for the top coat layer (ii) can be used. Examples of the content of water (Z) include a range of 1 to 60% by mass in the resin composition for forming a top coat layer.

The top coat layer (ii) contains the urethane resin (X), the beads (Y), and the water (Z) as essential components, but also contains other additives, if necessary. May be good.

Examples of the other additives include a cross-linking agent (S), a filler (T), an emulsifier, a defoaming agent, a leveling agent, a thickener, a viscoelasticity adjusting agent, a wetting agent, a dispersant, a preservative, and a plasticizer. , Penetrants, fragrances, bactericides, acaricides, fungicides, UV absorbers, antioxidants, antioxidants, flame retardants, dyes, pigments, auxiliary solvents and the like can be used. These additives may be used alone or in combination of two or more.

The cross-linking agent (S) is used for improving chemical resistance, abrasion resistance, and light resistance, and specifically, the cross-linking agent (S) that can be used for the primer layer (i). The same as E) can be used. Among these, it is preferable to use the oxazoline cross-linking agent (OXZ) and the carbodiimide cross-linking agent (NCN) in combination from the viewpoints of further excellent ethanol resistance and suppression of gloss change during stretching of the surface treatment layer, and its mass. The ratio [OXZ / NCN] is preferably in the range of 90/10 to 20/80, and more preferably in the range of 80/20 to 30/70.

When the cross-linking agent (S) is used, the amount used is preferably in the range of 0.1 to 5% by mass (as a solid content) in the resin composition for forming the top coat layer, and is in the range of 0.2 to 4% by mass. Is more preferable.

The filler (T) is used for adjusting the gloss and improving the texture, and specifically, the same filler (C) as the filler (C) that can be used for the primer layer (i). Can be used.

When the filler (T) is used, for example, the amount used is preferably in the range of 0.1 to 15% by mass, more preferably in the range of 0.2 to 10% by mass in the resin composition for forming the top coat layer.

The filling rate of the beads (Y) in the top coat layer (ii) is in the range of 25 to 90% from the viewpoint of excellent ethanol resistance and suppression of gloss change during stretching of the surface treatment layer. Is essential, more preferably in the range of 28-75%. Within this range, various physical properties and moldability are ensured, so it is presumed that excellent ethanol resistance and suppression of gloss change during stretching of the surface treatment layer can be obtained. The filling rate of the beads (Y) in the top coat layer (ii) shows a value calculated by the following formula.

[Replenishment under Rule 26 22.02.2021]

Bead filling rate calculation method for close-packed model

The bead (Y) filling rate ratio was determined by using the above formula as the 100% bead filling rate, with the formulation having the determined PVC value at the time of close-packing as the 100% bead filling rate.

Next, the surface-treated layer of the present invention will be described.

The surface treatment layer has the primer layer (i) and the top coat layer (ii).

As a method for producing the surface treatment layer, for example, the resin composition for forming a primer layer is applied onto a base material, dried, and then the resin composition for forming a top coat layer (ii) is applied thereto. Works and drying methods can be mentioned.

The thickness of the primer layer (i) includes, for example, the range of 2 to 30 μm, and the thickness of the top coat layer (ii) includes, for example, the range of 2 to 30 μm.

Examples of the base material include synthetic leather, polyvinyl chloride (PVC) leather, thermoplastic olefin resin (TPO) leather, dashboard, and instrument panel. Further, since the surface treatment layer of the present invention is particularly excellent in adhesion to TPO leather, it can be suitably used as a surface treatment agent for TPO leather.

As described above, since the surface treatment layer of the present invention uses a material containing water, it is environmentally friendly, has little change in gloss during stretching, and has excellent peel strength and ethanol resistance. In particular, the surface-treated layer of the present invention has excellent peel strength (adhesion) to TPO leather.

Hereinafter, the present invention will be described in more detail with reference to Examples.

[Synthesis Example 1] Preparation of aqueous dispersion of urethane resin (A-1) 250 parts by mass of methyl ethyl ketone and 0.001 parts by mass of stannous octylate in a four-necked flask equipped with a stirrer, a thermometer, and a nitrogen recirculation tube. Then, 200 parts by mass of polycarbonate polyol-1 (based on 1,4-butanediol and 1,6-hexanediol, number average molecular weight: 1,000), 2,2-dimethylol propionic acid 15 parts by mass, 49 parts by mass of isophorone diisocyanate and 34 parts by mass of hexamethylene diisocyanate were added and reacted at 70 ° C. for 1 hour to obtain a methyl ethyl ketone solution of a urethane prepolymer.
Next, 6.8 parts by mass of hydrazine and 15 parts by mass of triethylamine were mixed with the methyl ethyl ketone solution of this urethane prepolymer, and then 820 parts by mass of ion-exchanged water was added to emulsify the urethane resin (A-1) in water. Obtained liquid.
Next, methyl ethyl ketone was distilled off from the emulsion, and ion-exchanged water was further added to obtain a urethane resin (A-1) aqueous dispersion having a non-volatile content of 30% by mass.
The urethane resin (A-1) obtained had a urethane bond content of 2,052 mmol / kg, a urea bond content of 698 mmol / kg, and an alicyclic structure content of 715 mmol / kg.

[Synthesis Example 2] Preparation of water dispersion of urethane resin (A-2) 250 parts by mass of methyl ethyl ketone and 0.001 parts by mass of stannous octylate in a four-necked flask equipped with a stirrer, a thermometer, and a nitrogen recirculation tube. Then, 220 parts by mass of polycarbonate polyol-3 (based on 1,6-hexanediol, number average molecular weight: 2,000), 12 parts by mass of 2,2-dimethylolpropionic acid, dicyclohexylmethane. 70 parts by mass of diisocyanate was added and reacted at 70 ° C. for 1 hour to obtain a methyl ethyl ketone solution of urethane prepolymer.
Next, 4.5 parts by mass of piperazine and 9 parts by mass of triethylamine were mixed with the methyl ethyl ketone solution of this urethane prepolymer, and then 880 parts by mass of ion-exchanged water was added to emulsify the urethane resin (A-2) in water. Obtained liquid.
Next, methyl ethyl ketone was distilled off from the emulsion, and ion-exchanged water was further added to obtain a urethane resin (A-2) aqueous dispersion having a non-volatile content of 32% by mass.
The urethane resin (A-2) obtained had a urethane bond content of 1,278 mmol / kg, a urea bond content of 435 mmol / kg, and an alicyclic structure content of 1,713 mmol / kg.

[Preparation Example 1] Preparation of Resin Composition (i-1) for Forming Primer Layer 38 parts by mass of aqueous dispersion of urethane resin (A-1) obtained in Synthesis Example 1, olefin resin (polyether-based polymer chain) Acid-modified non-chlorinated polyolefin resin, "Arrow Base SD-1010" manufactured by Unitica Co., Ltd., non-volatile content; 20.5% by mass 5.5 parts by mass, silica particles produced by the dry method, average particle diameter: 10 μm, Hereinafter, it is abbreviated as "silica". ") 3.9 parts by mass, 44.5 parts by mass of water, 0.3 parts by mass of leveling agent ("BYK-342" manufactured by Big Chemie Japan Co., Ltd.), antifoaming agent (Sannopco) By mixing 0.1 parts by mass of "SN Deformer 777" manufactured by Co., Ltd., a resin composition for forming a primer layer (i-1) was obtained.

[Preparation Example 2] Preparation of Resin Composition for Forming Primer Layer (i-2) In Adjustment Example 1, the aqueous dispersion of the urethane resin (A-1) was changed to the aqueous dispersion of the urethane resin (A-2). A resin composition for forming a primer layer (i-2) was obtained in the same manner as in Preparation Example 1.

[Comparative Preparation Example 1] Preparation of Resin Composition for Forming Primer Layer (iR-1) In Adjustment Example 1, the amount of the urethane resin (A-1) aqueous dispersion used was changed from 38 parts by mass to 43.5 parts by mass. A resin composition for forming a primer layer (iR-1) was obtained in the same manner as in Preparation Example 1 except that the amount of the olefin resin used was changed from 5.5 parts by mass to 0 parts by mass.

[Comparative Preparation Example 2] Preparation of Resin Composition for Forming Primer Layer (iR-2) In Adjustment Example 1, the amount of the urethane resin (A-1) aqueous dispersion used was changed from 38 parts by mass to 38.6 parts by mass. A resin composition for forming a primer layer (iR-February) was obtained in the same manner as in Preparation Example 1 except that the amount of silica used was changed from 3.9 parts by mass to 3.3 parts by mass.

[Preparation Example 3] Preparation of Resin Composition (ii-1) for Forming Top Coat Layer 48.15 parts by mass of aqueous dispersion of urethane resin (A-1) obtained in Synthesis Example 1, urethane beads (Negami Kogyo Co., Ltd.) Manufactured by "ART PEARL C-600T", average particle size; 10 μm) 5.03 parts by mass, silica 3.33 parts by mass, water 34.59 parts by mass, auxiliary agent (butyl cellosolve) 0.49 parts by mass, thickener (thickening agent (butyl cellosolve) 2.6 parts by mass of ADEKA Co., Ltd. "UH-420"), 0.2 parts by mass of leveling agent ("BYK-342" manufactured by Big Chemie Japan Co., Ltd.), antifoaming agent ("SN Deformer 777" manufactured by Sannopco Co., Ltd. ) By mixing 0.2 parts by mass, a resin composition for forming a top coat layer (ii-1) was obtained.

[Preparation Example 4] Preparation of Resin Composition for Forming Top Coat Layer (ii-2) In Adjustment Example 3, the amount of urethane beads used was changed from 5.03 parts by mass to 2.83 parts by mass, and the amount of silica used was set to 3. Changed the amount of water used from .33 parts by mass to 3.97 parts by mass, the amount of water used from 34.59 parts by mass to 35.55 parts by mass, and the amount of thickener used from 2.6 parts by mass to 3.2 parts by mass. A resin composition for forming a top coat layer (ii-2) was obtained in the same manner as in Adjustment Example 3.

[Preparation Example 5] Preparation of Resin Composition for Forming Top Coat Layer (ii-3) In Adjustment Example 3, the amount of urethane beads used was changed from 5.03 parts by mass to 18.8 parts by mass, and the amount of silica used was set to 3. Changed the amount of water used from .33 parts by mass to 0.47 parts by mass, the amount of water used from 34.59 parts by mass to 23.78 parts by mass, and the amount of thickener used from 2.6 parts by mass to 2.5 parts by mass. A resin composition for forming a top coat layer (ii-3) was obtained in the same manner as in Adjustment Example 3.

[Preparation Example 6] Preparation of Topcoat Layer Forming Composition (ii-4) In Adjustment Example 3, a urethane resin (A-2) aqueous dispersion is used instead of the urethane resin (A-1) aqueous dispersion. A composition for forming a top coat layer (ii-4) was obtained in the same manner as in Preparation Example 3.

[Comparative Preparation Example 3] Preparation of Resin Composition for Forming Top Coat Layer (iiR-1) In Adjustment Example 3, the amount of urethane beads used was changed from 5.03 parts by mass to 2.17 parts by mass, and the amount of silica used was changed. A resin composition for forming a top coat layer in the same manner as in Adjustment Example 3 except that the amount of water used was changed from 3.459 parts by mass to 36.81 parts by mass from 3.33 parts by mass to 3.97 parts by mass. iiR-1) was obtained.

[Comparative Preparation Example 4] Preparation of Resin Composition for Forming Top Coat Layer (iiR-2) In Adjustment Example 3, the amount of urethane beads used was changed from 5.03 parts by mass to 21.5 parts by mass, and the amount of silica used was changed. A resin composition for forming a top coat layer in the same manner as in Adjustment Example 3 except that the amount of water used was changed from 3.459 parts by mass to 20.98 parts by mass from 3.33 parts by mass to 0.47 parts by mass. iiR-2) was obtained.

[Example 1]
In 100 parts by mass of the primer layer forming resin composition (i-1) obtained in Adjustment Example 1, a carbodiimide cross-linking agent (“Carbodilite SV-02” manufactured by Nisshinbo Chemical Co., Ltd., active ingredient; 40% by mass, carbodiimide equivalent) 430, hereinafter abbreviated as "NCN".) 2 parts by mass were blended. This was coated on a TPO leather sheet using a bar coater so that the wet film thickness was 30 μm, and dried at 120 ° C. for 1 minute to obtain a primer layer.
Next, in 100 parts by mass of the resin composition (ii-1) for forming the top coat layer obtained in Adjustment Example 3, 1 part by mass of NCN, an oxazoline cross-linking agent (“Epocross WS-500” manufactured by Nippon Shokubai Co., Ltd., active ingredient; 39% by mass, oxazoline equivalent; 220, hereinafter abbreviated as "OXZ") 1 part by mass was blended. This was coated on the primer layer with a bar coater so that the wet film thickness was 30 μm, and dried at 120 ° C. for 1 minute to obtain a top coat layer to obtain an article.

[Example 2]
Articles were obtained in the same manner as in Example 1 except that the NCN and OXZ used for the top coat layer were changed from 1 part by mass to 1.5 parts by mass, respectively.

[Example 3]
In Example 1, an article was obtained in the same manner as in Example 1 except that the amount of the NCN used for the primer layer was changed from 2 parts by mass to 2.5 parts by mass.

[Example 4]
In Example 1, the same as in Example 1 except that the resin composition for forming the top coat layer (ii-1) used for the top coat layer was changed to the resin composition for forming the top coat layer (ii-2). I got the goods.

[Example 5]
In Example 1, the same as in Example 1 except that the resin composition for forming the top coat layer (ii-1) used for the top coat layer was changed to the resin composition for forming the top coat layer (ii-3). I got the goods.

[Example 6]
In Example 1, the resin composition for forming a primer layer (i-1) used for the primer layer is changed to the resin composition for forming a primer layer (i-2), and the resin composition for forming the top coat layer used for the top coat layer is used. An article was obtained in the same manner as in Example 1 except that the resin composition (ii-1) was changed to the resin composition for forming a topcoat layer (ii-4).

[Comparative Example 1]
In Example 1, the same as in Example 1 except that the primer layer forming resin composition (i-1) used for the primer layer was changed to the primer layer forming resin composition (iR-1) and changed to. I got the goods.

[Comparative Example 2]
In Example 1, the same as in Example 1 except that the primer layer forming resin composition (i-1) used for the primer layer was changed to the primer layer forming resin composition (iR-2) and changed to. I got the goods.

[Comparative Example 3]
In Example 1, the resin composition for forming the top coat layer (ii-1) used for the top coat layer was changed to the resin composition for forming the top coat layer (iiR-1), except that the resin composition was changed to. An article was obtained in the same manner as in 1.

[Comparative Example 4]
In Example 1, the resin composition for forming the top coat layer (ii-1) used for the top coat layer was changed to the resin composition for forming the top coat layer (iiR-2), except that the resin composition was changed to. An article was obtained in the same manner as in 1.

[Measurement method of number average molecular weight]
The number average molecular weight of the polyol and the weight average molecular weight of the olefin resin used in the synthesis example show the values obtained by measuring under the following conditions by the gel permeation column chromatography (GPC) method.

Measuring device: High-speed GPC device ("HLC-8220GPC" manufactured by Tosoh Corporation)
Column: The following columns manufactured by Tosoh Corporation were connected in series and used.
"TSKgel G5000" (7.8 mm ID x 30 cm) x 1 "TSKgel G4000" (7.8 mm ID x 30 cm) x 1 "TSKgel G3000" (7.8 mm ID x 30 cm) x 1 This "TSKgel G2000" (7.8 mm ID x 30 cm) x 1 Detector: RI (Differential Refractometer)
Column temperature: 40 ° C
Eluent: tetrahydrofuran (THF)
Flow velocity: 1.0 mL / min Injection volume: 100 μL (tetrahydrofuran solution with a sample concentration of 0.4% by mass)
Standard sample: A calibration curve was prepared using the following standard polystyrene.

(Standard polystyrene)
"TSKgel Standard Polystyrene A-500" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene A-1000" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene A-2500" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene A-5000" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-1" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-2" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-4" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-10" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-20" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-40" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-80" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-128" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-288" manufactured by Tosoh Corporation
"TSKgel Standard Polystyrene F-550" manufactured by Tosoh Corporation

[Measuring method of gloss value of primer layer (i)]
The prepared solution for forming the primer layer was put on black art paper. Bar Coater No. 1 manufactured by Daiichi Rika Co., Ltd. 14 is used for coating so that the wet film thickness is about 30 μm. After that, it is put in a hot air dryer set at 120 ° C. for 1 minute to dry.
After taking it out of the dryer and cooling it to room temperature, the 60-degree mirror gloss of the coated surface was measured using a mirror gloss meter "Microtley Rohto" manufactured by Big Gardner.

[Evaluation method of gloss change during stretching]
The obtained article was molded using a vacuum forming machine so as to have a stretching ratio of 300%, and the appearance was observed before and after molding, and the 60-degree gloss value was measured by Big Gardner's "Microt League Loss". Was measured and evaluated as follows.
(appearance)
"○"; No abnormality is confirmed in appearance.
"X"; Whitening or cracking of the coating film is confirmed.
(60 degree gloss value)
"○"; The gloss change is less than 0.5.
"Δ"; The gloss change is 0.5 or more and less than 0.8.
"X"; The gloss change is 0.8 or more.

[Evaluation method of peel strength]
The surface of the obtained article was subjected to a T-shaped peeling test using Tencilon (manufactured by A & D Co., Ltd.), and the peeling strength (N / 15 mm) between the surface treatment layer and TPO leather was measured. , Evaluated as follows. Further, molding was carried out using a vacuum forming machine so as to have a stretching ratio of 150%, and the peel strength (N / 15 mm) of the stretched article was measured in the same manner and evaluated as follows.
"◎"; 20 or more.
"○"; 10 or more and less than 20.
"X"; less than 10.

[Evaluation method of ethanol resistance]
The surface of the obtained article is rubbed with a cotton cloth soaked in a 30 mass% ethanol aqueous solution under a load of 500 g using a Gakushin friction tester (“RT-200” manufactured by Daiei Kagaku Seiki Seisakusho Co., Ltd.). Then, the state of the coating film was observed and evaluated as follows.
"○": No peeling of the coating film is observed 300 times or more.
"X": Peeling of the coating film was confirmed less than 300 times.

It was found that the surface-treated layer of the present invention uses a water-containing material, has little change in gloss during stretching, and is excellent in peel strength and ethanol resistance.

On the other hand, in Comparative Example 1, although the primer layer (i) did not contain the olefin resin (B), the peel strength from the TPO leather and the ethanol resistance were poor.

Comparative Example 2 is a mode in which the gloss value of the primer layer (i) exceeds the range specified in the present invention, but the gloss change during stretching was remarkable.

In Comparative Example 3, the filling rate of the beads (Y) in the top coat layer (ii) was lower than the range specified in the present invention, but the gloss change during stretching was remarkable.

In Comparative Example 3, the filling rate of the beads (Y) in the top coat layer (ii) exceeds the range specified in the present invention, but the ethanol resistance is poor.

Claims (5)

1. A surface treatment layer having a primer layer (i) and a top coat layer (ii).
   The primer layer (i) is formed of a resin composition for forming a primer layer containing a urethane resin (A), an olefin resin (B), a filler (C), and water (D). The gloss value of the primer layer (i) is less than 0.9,
   The top coat layer (ii) is formed of a resin composition for forming a top coat layer containing urethane resin (X), beads (Y), and water (Z), and the top coat layer (ii) is formed from the top coat layer (ii). A surface-treated layer characterized in that the filling rate of the beads (Y) in ii) is in the range of 25 to 90%.
2. The surface treatment layer according to claim 1, wherein the content of the filler (C) in the resin composition for forming a primer layer is in the range of 1.5 to 10% by mass.
3. The surface treatment layer according to claim 1 or 2, wherein the beads (Y) in the resin composition for forming a top coat layer have an average particle size of 7 μm or more.
4. The surface treatment layer according to any one of claims 1 to 3, wherein the content of the beads (Y) in the resin composition for forming a top coat layer is in the range of 1.5 to 30% by mass.
5. An article characterized by having a thermoplastic olefin resin base material and a surface-treated layer according to any one of claims 1 to 4.