JP2005239815A - Two-pack type coating material composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a weak solvent type acrylic urethane coating material causing no appearance abnormality such as delustering and poor smoothness, even in the occurrence of dew condensation on a coating surface during the curing process of a coating film. <P>SOLUTION: The two-pack type coating material composition comprises a copolymer solution or dispersion (D) containing a hydroxy group-containing vinyl-based copolymer (A) having a polyester segment, a polyalkylene glycol (B) and an organic solvent (C), and a polyisocyanate (E), in which ≥20 wt.% of the organic solvent (C) is an aliphatic hydrocarbon solvent. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a two-component paint composition for interior and exterior of a building, and more particularly to a polyisocyanate-curing two-component paint composition used for repairing a metal roof mainly composed of tin.

  As the market for building repair coatings continues to grow, it contains organic solvents based on aliphatic hydrocarbon solvents, which are less toxic, and vinyl resins based on acrylic resins. The weak solvent type acrylic paint is suitable as a paint for repair because it is superior in winter coating workability, weather resistance, coating film properties, alkali resistance, and quick-drying compared with conventional emulsion paints and alkyd paints. It is recognized that

  In particular, the so-called weak solvent type acrylic urethane paint, which cures by reacting a hydroxyl group-containing vinyl resin with polyisocyanate, will damage the old paint film even if it is overcoated on the old paint film with insufficient solvent resistance. The resulting coating film has good weather resistance, water resistance and chemical resistance, and excellent durability and solvent resistance. Without being generated, the performance required for the coating material for repair is suitably provided. Therefore, the weak solvent type acrylic urethane paint has been used widely since the 1990s, particularly as a building exterior repair paint, iron part paint, and the like.

  As such a weak solvent type acrylic urethane paint, a resin composition for paint comprising a specific vinyl copolymer, polyisocyanate, a specific nonpolar organic solvent and a polar organic solvent can be used as a repair paint. It is reported that it is excellent in the property etc. (for example, refer patent document 1).

  However, when the coating resin composition is used as a tin roof repair coating, if condensation occurs on the coated surface in the process of leaving the coating overnight and curing the coating, it causes glossiness and poor smoothness. It became a problem. In particular, since condensation is likely to occur from autumn to early winter, conventional coatings for repair have not been able to form a coating film having an excellent appearance. In areas where there is a lot of snow, it is necessary to remove snow frequently, and there are many opportunities to repair tin roofs, so the development of repair paints that can form a coating film with excellent appearance even if condensation occurs Demanded by industry.

Japanese Patent Laid-Open No. 02-107680 (Claim 1, page 22, upper right column, lines 12 to 13)

  The problem to be solved by the present invention is to provide a weak solvent type acrylic urethane paint that does not cause appearance abnormality such as glossiness or poor smoothness even if condensation occurs on the painted surface in the curing process of the coating film. .

  The present inventors believe that the appearance defect caused by condensation causes unevenness in the coating film when water droplets generated by condensation evaporate from the surface of the coating film, and the uneven coating film is cured as it is. An attempt was made to solve the above-mentioned problems by using a soft resin for the repair coating to soften the coating film.

  However, the resulting coating film has a long-lasting tackiness and is inadequate in terms of dryness. For practical use, the next day after painting, when an operator re-repairs, the paint adheres to footwear or clothes. There's a problem. Moreover, since the cured coating film is soft, there are problems such as poor stain resistance.

  Therefore, the present inventors can form a soft coating film so that the unevenness returns to flatness after evaporation of the condensed water, although the coating film has unevenness due to evaporation of the condensed water during the night after painting. Developed a paint composition that can be cured rapidly by increasing the temperature of the daytime, and that, after it has been completely cured, exhibits sufficient coating film hardness, and also has excellent drying and contamination resistance. It was.

  As a result, a two-component coating composition using a weak solvent solution or dispersion of a hydroxyl group-containing vinyl copolymer modified with a polyester resin as a hard component, and a polyalkylene glycol and a polyisocyanate as soft components It was found to be excellent in hardness, drying property and stain resistance, and also excellent in adhesion to the old paint film and pigment dispersibility.

  That is, the present invention relates to a copolymer solution or dispersion (D) containing a hydroxyl group-containing vinyl copolymer (A) having a polyester segment, a polyalkylene glycol (B) and an organic solvent (C) and a polyisocyanate ( E) and 20% by weight or more of the organic solvent (C) is an aliphatic hydrocarbon solvent, and the polyalkylene glycol (B) is dissolved in the organic solvent (C). The composition unit of the polyester resin in the hydroxyl group-containing vinyl copolymer (A) having the polyester segment is preferably 1 to 50% by weight. And the glass transition temperature of the vinyl polymer portion other than the polyester segment determined from the Fox formula is 20 ° C. or higher. Preferably, the hydroxyl group-containing vinyl copolymer (A) having the polyester segment has a hydroxyl value of 10 to 100, and preferably the content of the polyalkylene glycol (B) is the polyester segment. The present invention relates to a two-component coating composition that is 0.5 to 10% by weight with respect to the hydroxyl group-containing vinyl copolymer (A).

  According to the two-component coating composition of the present invention, particularly when used as a tin roof repair coating, even if dew condensation occurs after coating, appearance abnormalities such as gloss and poor smoothness do not occur.

  Hereinafter, the present invention will be described in detail based on the embodiments.

  (1) Hydroxyl group-containing vinyl copolymer having a polyester segment (A)

  The hydroxyl group-containing vinyl copolymer (A) used in the present invention has a polyester segment, for example, a method of copolymerizing various vinyl monomers with a double bond of a polyester, or a polyester has. It can be produced by reacting a functional group with a vinyl polymer having a functional group capable of reacting with the functional group.

  The polyester used in the present invention is capable of reacting with a hydroxyl group-containing vinyl monomer described later, for example, an alkyd resin obtained using (semi) drying oil, and reacting with a hydroxyl group-containing vinyl monomer described later. And polyester resins having acid groups and hydroxyl groups that can be used.

  Examples of the hydroxyl group-containing vinyl monomer used for producing the hydroxyl group-containing vinyl copolymer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 3-hydroxypropyl (meta). ) Acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, di-2-hydroxyethyl fumarate or mono-2-hydroxyethyl-monobutyl fumarate , Polyethylene glycol- or polypropylene glycol mono (meth) acrylate or adducts of these with ε-caprolactone, “Placcel FM or FA monomer” [trade name of caprolactone addition monomer manufactured by Daicel Chemical Industries, Ltd.] And various hydroxyalkyl esters of α, β-ethylenically unsaturated carboxylic acid.

  In the present invention, in addition to the above-mentioned hydroxyl group-containing vinyl monomer, other vinyl monomers can be used as a copolymerization component within the scope of achieving the object of the present invention.

  Examples of known and commonly used vinyl monomers include (c) styrene monomers such as styrene, vinyl toluene, p-methyl styrene, ethyl styrene, propyl styrene, isopropyl styrene, and p-tert-butyl styrene;

(D) methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, iso (i) -propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, tert- Butyl (meth) acrylate, sec-butyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate or lauryl (meth) acrylate, “Acryester SL” [Mitsubishi Rayon Co., Ltd., C ₁₂ - _/ tradename _{C 13} methacrylate mixture, stearyl (meth) acrylate _{[C 18];} isostearyl (meth) acrylate _{[C 18];} alkyl (meth) acrylates such as behenyl (meth) acrylate _{[C 22]} Cyclohexyl (meta ) (Meth) acrylates containing no functional group in the side chain such as acrylate, 4-tert-butylcyclohexyl (meth) acrylate or isobornyl (meth) acrylate, adamantyl (meth) acrylate, benzyl (meth) acrylate;

  (E) Various unsaturated mono- or dicarboxylic acids such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid or citraconic acid or dicarboxylic acid monoesters such as monoethyl fumarate and monobutyl maleate;

  (F) Tertiary amino group-containing monomers such as various dialkylaminoalkyl (meth) acrylates such as dimethylaminoethyl (meth) acrylate or diethylaminoethyl (meth) acrylate; (meth) acrylonitrile; (meth) acrylamide, dimethyl (meta ) Various amide bond-containing vinyl systems such as acrylamide, N-tert-butyl (meth) acrylamide, N-octyl (meth) acrylamide, diacetone acrylamide, dimethylaminopropyl acrylamide or alkoxylated N-methylolated (meth) acrylamide Nitrogen-containing vinyl monomers such as monomers;

  (G) Various alkoxyalkyl (meth) acrylates such as methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate or methoxybutyl (meth) acrylate;

  (H) Diesters of various dicarboxylic acids typified by maleic acid, fumaric acid or itaconic acid such as dimethyl maleate, diethyl maleate, diethyl fumarate, dibutyl fumarate or dibutyl itaconate;

  (I) Various vinyl esters such as vinyl acetate, vinyl benzoate or “Beoba” (trade names of vinyl esters of branched (branched) aliphatic monocarboxylic acids, manufactured by Shell of the Netherlands);

  (Nu) “Biscoat 3F, 3FM, 8F, 8FM or 17FM” [trade name of fluorine-containing acrylic monomers manufactured by Osaka Organic Chemical Co., Ltd.], perfluorocyclohexyl (meth) acrylate, di-perfluorocyclohexyl fuma Various (per) fluoroalkyl group-containing vinyl esters such as rate or Ni-propyl perfluorooctanesulfonamidoethyl (meth) acrylate, -vinyl ether,-(meth) acrylate or -unsaturated polycarboxylic acid ester, etc. Various fluorine-containing polymerizable compounds;

  (L) Phosphorus atom-containing vinyl such as dialkyl [(meth) acryloyloxyalkyl] phosphate or (meth) acryloyloxyalkyl acid phosphate, dialkyl [(meth) acryloyloxyalkyl] phosphite or (meth) acryloyloxyalkyl acid phosphite System monomers;

  (O) Epoxy group-containing polymerizable compounds such as glycidyl (meth) acrylate, (β-methyl) glycidyl (meth) acrylate or (meth) allyl glycidyl ether can be used.

  When the other vinyl monomer is used, among the polyester segment and the hydroxyl group-containing vinyl polymer segment constituting the hydroxyl group-containing vinyl copolymer (A) to be obtained, Fox of the hydroxyl group-containing vinyl polymer segment It is preferable from the viewpoints of the drying property, hardness, tackiness, etc. of the coating film that the glass transition temperature determined by the formula

  Here, the glass transition temperature (hereinafter abbreviated as Tg) in the present invention is a value calculated by the generally known Fox equation shown below. For calculation, the Tg of the homopolymer is: Values generally described in the literature can be used. Furthermore, it can obtain | require also by measuring using a differential scanning calorimetry method and a dynamic viscoelasticity measuring method.

1 / Tg = Σ (Wn / Tgn)
Tg: Glass transition temperature of polymer (absolute temperature)
Wn: weight fraction of monomer n Tgn: glass transition temperature (absolute temperature) of homopolymer of monomer n

  Examples of the organic solvent (C) solution of the hydroxyl group-containing vinyl copolymer (A) having a polyester segment used in the present invention include the above hydroxyl group in the organic solvent (C) solution of a polyester resin having a (semi) drying oil component. Drop vinyl-containing monomers and other vinyl monomers in the presence or absence of radical polymerization initiators either collectively or separately, and graft polymerize the vinyl monomers directly onto the unsaturated bonds of the polyester resin. Can be manufactured. In addition, a vinyl monomer having a functional group capable of reacting with an acid group or a hydroxyl group of a polyester resin was previously graft-polymerized in an organic solvent (C) solution of an oil-free polyester resin containing no (semi) drying oil component. It can be produced by dropping a macromonomer and another vinyl monomer together or separately in the presence of a radical polymerization initiator to cause radical polymerization.

  At this time, the use amount of the polyester resin is based on the hydroxyl group-containing vinyl copolymer (A) having a polyester segment from the viewpoint of adhesion to the old coating film and pigment dispersibility of the obtained two-component coating composition. It is preferably 1 to 50% by weight.

  Examples of such radical polymerization initiators include azobisisobutyronitrile (AIBN), benzoyl peroxide (BPO), tert-butyl perbenzoate (TBPB), tert-butyl hydroperoxide (TBHPO), di-tert- And butyl peroxide (DTBPO), cumene hydroperoxide (CHP) or o, o-tert-o- (1,2,2,6,6-pentamethyl-4-piperidinyl) monoperoxycarbonate, etc. Can be used alone or in combination of two or more.

  The weight ratio of the hydroxyl group-containing vinyl copolymer (A) having a polyester segment in the organic solvent (C) solution of the hydroxyl group-containing vinyl copolymer (A) having the polyester segment obtained by the method is 50-60. It is preferable that it is weight%.

  In the present invention, a dispersion in which the hydroxyl group-containing vinyl copolymer (A) having the polyester segment is dispersed in the organic solvent (C) can also be used.

  Such a dispersion is obtained by dispersing the hydroxyl group-containing vinyl copolymer (A) having the polyester segment in an organic solvent (C). For example, an organic solvent of a polyester resin having a (semi) drying oil component ( C) The hydroxyl group-containing vinyl monomer, relatively high-polarity vinyl monomer and other vinyl monomers are dropped into the solution all at once or separately in the presence of a radical polymerization initiator, and dispersed particles are added. It can be manufactured by forming. In addition, a vinyl monomer having a functional group capable of reacting with an acid group or a hydroxyl group of a polyester resin was previously graft-polymerized in an organic solvent (C) solution of an oil-free polyester resin containing no (semi) drying oil component. It can be produced by radically polymerizing a macromonomer, a relatively high-polarity vinyl monomer, and other vinyl monomers in the presence or absence of a radical polymerization initiator.

  When manufacturing the said dispersion liquid, it is preferable to use a vinyl monomer with comparatively high polarity, for example, using (meth) acrylic acid acrylate, 2-hydroxyethyl (meth) acrylate, ethyl acrylate, etc. It is preferable in terms of stability in the organic solvent (C).

  The dispersion described above can be used by mixing with an organic solvent (C) solution of a hydroxyl group-containing vinyl copolymer (dispersion stabilizer) having a polyester segment that is soluble in the organic solvent (C).

  In that case, the solid content ratio of the dispersion stabilizer / dispersed particles is preferably in the range of 10/90 to 70/30. Is more preferable, the range of 20/80 to 70/30 is more preferable, and the range of 20/80 to 70/30 is still more preferable. Further, from the viewpoint of coating film performance and coating workability, the number average molecular weight of the dispersion stabilizer and dispersed particles is preferably controlled to about 5000 to 20000.

  The number average molecular weight of the hydroxyl group-containing vinyl copolymer (A) having the polyester segment thus obtained is preferably 5,000 to 20,000, and is preferably in the range of 5,000 to 15,000. It is preferable from the viewpoint.

  The hydroxyl group-containing vinyl copolymer (A) having the polyester segment preferably has a hydroxyl value of 10 to 100, more preferably in the range of 15 to 80, from the viewpoint of the performance of the resulting coating film. More preferably, it is in the range of 25-70.

  (2) Polyalkylene glycol (B)

  The polyalkylene glycol (B) used in the present invention dissolves in the organic solvent (C) described later and is compatible with the vinyl polymer and the polyisocyanate (D) described below. What is below is preferable and what is 200-1000 is more preferable.

  Examples of the polyalkylene glycol (B) include polyethylene glycol and polypropylene glycol. Particularly, polyethylene glycol includes “# 200, # 300, # 400, # 600” [above, Daiichi Kogyo Seiyaku ( Manufactured by Co., Ltd.]; as polypropylene glycol, “Hyprox MP-600” (produced by Dainippon Ink & Chemicals, Inc.), “Diol-400, Diol-700, Diol-1000” [above, Mitsui Chemicals, Inc. “PTMG650, PTMG850, PTMG1000” [manufactured by Mitsubishi Chemical Corporation], etc. are preferable.

  The polyalkylene glycol (B) is preferably used in an amount of 0.5 to 10% by weight based on the hydroxyl group-containing vinyl copolymer (A) having the polyester segment. By using such a range, it is soft enough to smooth the unevenness caused by condensation after coating, and can exhibit sufficient hardness and stain resistance after curing.

  (3) Organic solvent (C)

  The organic solvent (C) used in the present invention contains an aliphatic hydrocarbon solvent in an amount of 20% by weight or more. Examples of the aliphatic hydrocarbon solvent include normal hexane, normal heptane, “IP solvent 1016”. 1620 "[made by Idemitsu Petrochemical Co., Ltd.];" Isopar E, G, H "[produced by Exxon];" Marcazole R "(manufactured by Maruzen Petrochemical Co., Ltd.);" Kyowasol C-900 "[Kyowa Hakko ( Commercially available products can be used.

  As the organic solvent (C), a mixed solvent containing a specific amount of an aromatic hydrocarbon solvent can be used in addition to the aliphatic hydrocarbon solvent as the main component. Examples of the mixed solvent include “Pegazole 3040” (aliphatic hydrocarbon solvent / aromatic hydrocarbon solvent = 85/15 weight ratio), “Pegazole AN45” (aliphatic hydrocarbon solvent / aromatic hydrocarbon solvent = 70 / 30 weight ratio) (both manufactured by Exxon Mobil); “LAWS” (aliphatic hydrocarbon solvent / aromatic hydrocarbon solvent = 70/30 weight ratio), “HAWS” (aliphatic hydrocarbon solvent / aromatic) Hydrocarbon solvent = 50/50 weight ratio (all manufactured by Shell Japan Co., Ltd.); “New Solvent” (aliphatic hydrocarbon solvent / aromatic hydrocarbon solvent = 70/30 weight ratio) [manufactured by Nippon Oil Corporation ] Etc. are mentioned.

  As an organic solvent (C), what mixed the said aliphatic hydrocarbon solvent and the other organic solvent shown below can be used.

  Examples of such other organic solvents include (yo) alicyclic hydrocarbon solvents such as cyclohexane, methylcyclohexane, “Exol D30, D40” (manufactured by Exxon Mobil), “Shellsol D40” [Shell Japan, Inc. Made] etc .;

  (Ta) Aromatic hydrocarbon solvents such as toluene, xylene, “Solvesso 100, 150” (manufactured by Exxon Mobil); “Swazole 1000, 1500” (manufactured by Maruzen Petrochemical Co., Ltd.), etc.

  (L) Ester solvents such as ethyl acetate, (iso) propyl acetate, (iso) butyl acetate, 2-ethoxyethyl acetate, 3-methoxybutyl acetate, amyl acetate, ethoxyethyl propionate and the like;

  (So) ketone solvents such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), cyclohexanone, etc .;

  (Ii) ether solvents such as diethyl ether, diethylene glycol dimethyl ether, etc .;

  (E) Alcohol solvents such as ethyl alcohol, isopropyl alcohol, (iso) butanol, 3-methoxy-1-butanol, 3-methoxy-3-methyl-1-butanol, etc .; When an isocyanate is used as a curing agent, the isocyanate group of the polyisocyanate and the hydroxyl group of the alcohol solvent can react and be used within a range that does not hinder curing.)

  (Na) Glycol ester solvents such as cellosolve acetate; 3-methoxy-3-methylbutyl acetate, methoxypropyl acetate and the like;

  (La) Glycol ether solvents, such as methyl cellosolve, ethyl cellosolve, propylene glycol monoethyl ether, butyl cellosolve; diethylene glycol monobutyl ether, etc .; (However, glycol ether solvents are used when polyisocyanates described later are used as curing agents. The isocyanate group of the polyisocyanate and the hydroxyl group of the glycol ether solvent can be used within a range that does not inhibit the curing.

  The aliphatic hydrocarbon solvent is preferably contained in the organic solvent (C) in an amount of 30 to 85% by weight, and preferably 40 to 85% by weight. By adjusting to such a range, the coating composition which can fully dissolve the hydroxyl group-containing vinyl copolymer (A) and polyalkylene glycol (B) having the polyester segment and does not attack the old coating film. Can be obtained.

(4) Polyisocyanate The two-component coating composition of the present invention is an organic solvent (C) comprising a hydroxyl group-containing vinyl copolymer (A) having a polyester segment and a polyalkylene glycol (B). A solution or dispersion is used in combination with polyisocyanate as a curing agent.

  Examples of such polyisocyanates include toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), hydrogenated XDI, and hydrogenated MDI. Derivatives of allophanates, biurets, uretdiones, isocyanurates, adducts, etc .; and polyisocyanates blocked with lactams, alcohols or oximes, such as “Bernock DB-980K” [Dainippon Ink Chemical Co., Ltd. ( Co., Ltd. Products] etc. Blocked isocyanates and the like can be used.

  When using the two-component coating composition of the present invention, particularly as a coating for building exteriors, the weather resistance of the resulting coating film is required, but in order to impart weather resistance to the coating film, It is preferable to use aliphatic and / or alicyclic polyisocyanates, especially polyisocyanates having good stability in the organic solvent (C). For example, “Bernock DN-990, DN-991, DN-991S”. , DN-992 "[Dainippon Ink Chemical Co., Ltd. product]," Desmodur Z-4370 "[Sumitomo Bayer Urethane Co., Ltd. product] or" Duranate THA-100 "[Asahi Kasei Kogyo Co., Ltd.] It is done.

  As the use amount of the polyisocyanate, an equivalent ratio of [hydroxyl group having a hydroxyl group-containing vinyl copolymer (A) having a polyester segment + hydroxyl group having a polyalkylene glycol (B)] / [isocyanate group having a polyisocyanate] Is preferably in the range of 1.0 / 0.5 to 1.0 / 1.5, more preferably in the range of 1.0 / 0.7 to 1.0 / 1.2. Within such a range, a coating film having sufficient curability can be obtained, and foaming does not occur when it is applied to a coated surface having a high water content.

  Examples of the two-component coating composition of the present invention include pigment dispersants such as “Disperbyk-161, BYK-P104” [both manufactured by Big Chemie, Germany]; for example, “BYK-302” [Big Chemy, Germany] Leveling agents such as “BYK-065” [BIC Chemie product of Germany], “Disparon OX-70” [product of Enomoto Kasei Co., Ltd.], etc .; for example, “DISPARON 6820- 20M "[Enomoto Kasei Co., Ltd. product] and other anti-sagging agents;" Tinubin P, 328 "[both products manufactured by Ciba-Geigy, Switzerland], etc .; for example," Tinubin 770, 765 "[ All of these are light stabilizers such as products from Ciba-Geigy, Switzerland], antifungal agents, such as cobalt-based, lead-based, zirconium-based or calcium-based In the present invention, various commonly used additives for paints commonly used in the paint industry, such as all the so-called metal dryers or curing accelerators such as dibutyltin dilaurate as used so far, are used in the present invention. Can be used within the scope of achieving the purpose.

  Further, in the present invention, the above-mentioned dryers as auxiliary crosslinking agents, aluminum-based, zirconium-based or titanium-based metal alkoxides, metal acylates or metal chelates (for example, “acetope” [product of Hope Pharmaceutical Co., Ltd.], “ "Chita Coat" [Nippon Soda Co., Ltd. product], "Plenact" [Ajinomoto Co., Ltd. product], "Orgachix TA series, TC series, ZA series, ZB series, ZC series or AL series" [Matsumoto Pharmaceutical Co., Ltd. products ], "AIPD, AMD, ASBD or ALCH series" or "Aluminum chelate A, D or M" [Kawaken Fine Chemical Co., Ltd. product] or "Tencalate TP series" [Tenka Polymer Co., Ltd. product]), etc. It can be used as long as the effects of the invention are not impaired.

  Further, for the purpose of improving the performance of the two-component coating composition of the present invention, if it is soluble in the organic solvent (C), for example, a plasticizer, an acrylic copolymer, a fiber compound, an acrylate An alkyd resin, an alkyd resin, a silicon resin, a fluororesin, an epoxy resin, a condensate of a silane compound or the like as a low-contamination agent can be used in combination as appropriate within the scope of achieving the object of the present invention.

  In addition, the two-component coating composition of the present invention can be used as, for example, a clear coating that does not use pigments, a metallic coating in which aluminum powder or the like is dispersed, and a colored coating that uses a pigment.

  Examples of such pigments include inorganic pigments such as titanium oxide, carbon black, petal, and yellow; organic pigments such as cyanine blue and cyanine green; so-called extender pigments such as calcium carbonate, precipitated barium sulfate, talc, and clay; And dispersed pigments and processed pigments. The pigment is an organic solvent (C) solution or dispersion of the hydroxyl group-containing vinyl monomer (A), or an organic solvent of the hydroxyl group-containing vinyl monomer (A) and polyalkylene glycol (B) ( C) It can be mixed with a solution or a dispersion and kneaded and dispersed using, for example, a known and common device such as a sand mill, a ball mill, a three roll, a paint conditioner.

  In addition, a high-concentration resin composition obtained by kneading the organic solvent (C) solution or dispersion of the hydroxyl group-containing vinyl monomer (A) and polyalkylene glycol (B) with a pigment, if necessary In addition, those letdown with various vinyl copolymers can also be used as enamel paints.

  The two-component coating composition of the present invention thus obtained is particularly preferably used as a tin roof repair coating in which the above-mentioned poor appearance at the time of condensation is feared. For example, aluminum, stainless steel, chromium -Metal products such as aluminum sashes and gates made of various metal materials such as plating, tin plate or tin plate; or roof tiles; and various building interior and exterior materials such as building exterior walls and inorganic building materials; doors, handrails, etc. It can be used widely as a paint for interior and exterior of buildings including iron parts and PVC base materials.

  The two-component coating composition of the present invention can be applied to the above-mentioned substrate by a known and common method such as spraying, brushing or roller.

  Next, the present invention will be described more specifically with reference examples, examples and comparative examples. In the following, all parts are based on weight unless otherwise specified.

  Reference Example 1 [Preparation Example of Hydroxyl-Containing Vinyl Copolymer (A1) Having Polyester Segment]

  In a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas inlet tube, “LAWS” (shell hydrocarbon solvent. Aliphatic hydrocarbon solvent / aromatic hydrocarbon solvent = 70/30 ) 235.7 parts, "Beccosol P-470-70" (Dainippon Ink & Chemicals, soybean oil-based long oil alkyd resin; nonvolatile content 70 wt%, solvent "LAWS") Was heated up to 120 ° C.

  When the temperature reached 120 ° C., 200 parts of styrene (hereinafter abbreviated as St), 525 parts of i-butyl methacrylate (hereinafter abbreviated as i-BMA), 2-ethylhexyl acrylate (hereinafter abbreviated as 2EHA). 40 parts, 82 parts of 2-hydroxyethyl acrylate (hereinafter abbreviated as 2-HEMA), 2 parts of methacrylic acid (hereinafter abbreviated as MAA), and tert-butylperoxy (as a polymerization initiator) 2-ethyl hexanoate) (hereinafter abbreviated as perbutyl O) and 400 parts of “LAWS” were added dropwise over 4 hours, held at the same temperature for 8 hours, and then added with 300 parts of xylene. Thus, an organic solvent solution of the hydroxyl group-containing vinyl copolymer (A1) having a polyester segment was obtained.

  The organic solvent solution of the obtained hydroxyl group-containing vinyl copolymer (A1) has a non-volatile content of 50.0% by weight; a Gardner viscosity at 25 ° C. of XY; a solution acid value of 2.0; 2; Solid content hydroxyl value 40; aliphatic hydrocarbon solvent weight in organic solvent 49% by weight; design Tg of acrylic part 40 ° C.

  Reference example 2 [Preparation example of non-aqueous dispersion type resin (A2)]

  In the same apparatus as in Reference Example 1, 1000 parts of the polyester resin-modified hydroxyl group-containing vinyl copolymer (A1) obtained in Reference Example 1 and “LAWS” for use as a dispersion stabilizer for a non-aqueous dispersion type resin. 200 parts of was charged and the temperature was raised to 100 ° C. When the temperature reached 100 ° C., 186 parts of methyl methacrylate (hereinafter abbreviated as MMA), 266 parts of ethyl acrylate (hereinafter abbreviated as EA), 47 parts of 2-HEMA, 1 part of MAA, and polymerization A mixture of 2 parts of perbutyl O as an initiator and 300 parts of “LAWS” was dropped over 4 hours and held at the same temperature for 8 hours to obtain an organic solvent dispersion of the non-aqueous dispersion type resin (A2). It was. The obtained organic solvent dispersion of the non-aqueous dispersion resin (A2) has a nonvolatile content of 50.0% by weight; a Gardner viscosity at 25 ° C. of W; a solution acid value of 2.0; a solid content hydroxyl value of 40. The weight of the aliphatic hydrocarbon solvent in the organic solvent was 59.5% by weight; the design Tg of the acrylic part was 29 ° C.

  Reference Example 3 [Preparation Example of Hydroxyl-Containing Vinyl Copolymer (A3) Without Polyester Segment]

  300 parts of “LAWS” was charged into the same apparatus as in Reference Example 1, and the temperature was raised to 120 ° C. At 120 ° C., 200 parts of St, 593 parts of i-BMA, 112 parts of 2-EHA, 93 parts of 2-HEMA, 2 parts of MAA, and 2 parts of perbutyl O which is a polymerization initiator Then, a mixture of 2 parts of perbutyl O and 400 parts of “LAWS” was added dropwise over 4 hours, held at the same temperature for 8 hours, and then 300 parts of xylene was added to obtain a solvent-soluble resin (A3) Got. The resulting organic solvent solution of the hydroxyl group-containing vinyl copolymer (A3) not modified with a polyester resin has a nonvolatile content of 50.0% by weight; a Gardner viscosity at 25 ° C. of W; a solution acid value of 2.0. The Gardner color number was 1 or less; the solid content hydroxyl value was 40; the weight of the aliphatic hydrocarbon solvent in the organic solvent was 49% by weight; and the design Tg of the acrylic part was 40 ° C.

  Reference Example 4 [Preparation Example of Hydroxyl-Containing Vinyl Copolymer (A4) Organic Solvent Solution Having Polyester Segment]

  In the same apparatus as in Reference Example 1, 150 parts of xylene, 85.7 parts of “LAWS” “Beccosol P-470-70” (a soybean oil-based long oil alkyd resin manufactured by Dainippon Ink & Chemicals, Inc .; nonvolatile content) 704.3 wt%, solvent “LAWS”) and 234.3 parts, and the temperature was raised to 120 ° C. When the temperature reached 120 ° C., 200 parts of styrene (hereinafter abbreviated as St), 526 parts of i-butyl methacrylate (hereinafter abbreviated as i-BMA), 2-ethylhexyl acrylate (hereinafter abbreviated as 2EHA). 40 parts, 82 parts of 2-hydroxyethyl acrylate (hereinafter abbreviated as 2-HEMA), 2 parts of methacrylic acid (hereinafter abbreviated as MAA), and tert-butylperoxy (as a polymerization initiator) 2-ethylhexanoate) (hereinafter abbreviated as perbutyl O) and 400 parts of xylene are added dropwise over 4 hours, held at the same temperature for 8 hours, and then 300 parts of xylene are added. A polyester resin-modified hydroxyl group-containing vinyl copolymer (A4) organic solvent solution was obtained. The obtained hydroxyl group-containing vinyl copolymer (A4) organic solvent solution having polyester segments has a non-volatile content of 50.0% by weight; a Gardner viscosity at 25 ° C. of U; a solution acid value of 2.0; The number was 2, the hydroxyl value of the solid content was 40, the weight of the aliphatic hydrocarbon solvent in the organic solvent was 15% by weight, and the Tg of the acrylic part was 40 ° C.

Paint-based preparation example 1 (abbreviation: BP1)
180 parts of an organic solvent solution of the vinyl copolymer (A1) obtained in Reference Example 1, 4 parts of “Taipek R-930 (titanium oxide manufactured by Ishihara Sangyo Co., Ltd.)”, “Mitsubishi Carbon MA-100” [ 3 parts of “Mitsubishi Chemical Carbon Black”, 5 parts of “Todacolor 140-ED” [Valley manufactured by Toda Kogyo Co., Ltd.] 3 ”[Iron Oxide Yellow manufactured by Toyo Dye Industry Co., Ltd.] was kneaded with a sand mill and then diluted with“ LAWS ”so that the steamer viscosity was 70 KU at 25 ° C. to obtain a paint base (BP1) having a PWC of 20 wt% .

Paint-based preparation example 2 (abbreviation: BP2)
Except for replacing the organic solvent solution of the vinyl copolymer (A1) with the organic solvent dispersion of the non-aqueous dispersion type resin (A2), a paint base (BP2) having a PWC of 20% by weight was prepared in the same manner as in Preparation Example 1. Got.

Paint-based preparation example 3 (abbreviation: BP3)
A paint base (BP3) having a PWC of 20% by weight is obtained in the same manner as in Preparation Example 1 except that the organic solvent solution of the vinyl copolymer (A1) is replaced with the organic solvent solution of the vinyl copolymer (A3). It was.

Paint-based preparation example 4 (abbreviation: BP4)
In the same manner as in Preparation Example 1 except that the organic solvent solution of the vinyl copolymer (A1) is replaced with the organic solvent solution of the vinyl copolymer (A4), a paint base (BP4) containing 20 wt. Obtained.

Examples 1-5 and Comparative Examples 1-3
Table 1 shows polypropylene glycol (hereinafter abbreviated as PPG) “Hyprox MP-600” [Dainippon Ink & Chemicals, Inc.] with respect to the vinyl copolymers in the paint bases (BP1) to (BP4). In addition, the weak solvent-soluble polyisocyanate “Bernock DN-990” [Dainippon Ink Chemical Co., Ltd.] is added to the hydroxyl group of the vinyl copolymer and PPG and the polyisocyanate. It compounded so that an equivalent ratio with an isocyanate group might be set to 1, and 150 g / m < ² > was coated on the tin plate.

1) Shrinkage occurs with long oil alkyd paint, one-part acrylic paint, one-part acrylated alkyd paint 2) Adhesion failure with long-oil alkyd paint, one-part acrylic paint, one-part acrylated alkyd paint 3) Long oil Poor adhesion with alkyd paint, one-part acrylic paint, one-part acrylated alkyd paint PHR represents a weight ratio with respect to 100 parts by weight of resin.

1. Color separation <Evaluation method>
When the paint shown in Table 1 is applied to a tin plate with a brush of 150 g / m2 and the touch-drying after about 20 minutes is not finished, the presence or absence of a color difference from the peripheral part when rubbing with a finger, and after the touch-drying Then, a part of the remaining paint is hung on the coating film, and after drying, it is judged by the presence or absence of a color difference from the peripheral part.

<Evaluation criteria>
○: There is almost no color difference and the color difference is not a problem in the market.
Δ: A level where a slight color difference is recognized and there is a concern about problems in the market.
X: Color difference is regarded as a problem in the market.

2. Old paint shrinkage <Evaluation method>
Long oil alkyd paint (soybean oil), one-part acrylic paint (vinyl acetate-acrylic type), one-part acrylated alkyd-based tin repair paint (containing 30% by weight of alkyd), BP1 described in Preparation Example 1 The acrylic urethane-based paint shown was applied to a tin plate at 150 g / m ² and dried, and the resulting coating film was deteriorated for 500 hours with a sunshine weatherometer, and then the paint of the present invention shown in Table 1 was overcoated. Evaluation of shrinkage of coating film.

<Evaluation criteria>
○: Level at which the entire coating does not shrink.
Δ: Level at which slight shrinkage occurs in some coating films.
X: A level at which significant shrinkage occurs in some coating films and shrinkage is regarded as a problem in the market.

3. Old film adhesion <Evaluation method>
After the coating film of the long oil alkyd paint, the one-part acrylic paint, the one-part acrylated alkyd-type tin repair paint, and the weak solvent acrylic urethane paint described in Preparation Example 1 is deteriorated with a sunshine weatherometer for 500 hours. Then, the paint of the present invention shown in Table 1 was overcoated, and a 1 mm square cross-cut adhesion test (cello tape peeling) was conducted after one week.

<Evaluation criteria>
○: Adhesiveness level of 90/100 or more on all coating films.
(Triangle | delta): Adhesiveness is the level of 50/100-90/100 on all the coating films.
X: Adhesiveness is less than 50/100 on all coating films, or the level of full peeling with some coating films.

4). Condensation appearance <Evaluation method>
The paint shown in Table 1 was applied to a tin plate with 150 g / m ² brush, dried for 2 hours, then placed in a high-temperature humidifier at 10 ° C./90% RH, taken out the next morning, and exposed to sunlight for 2 hours. Evaluated with high gloss.

<Evaluation criteria>
○: Level at which the 20 ° gloss value exceeds 60.
(Triangle | delta): A 20 degree gloss value is a level of 35-60.
X: Level at which the 20-degree gloss value is less than 35.

5). Next day coating film <Evaluation method>
The paints shown in Table 1 and ² brushing 150 g / m to tinplate, after 18 hours drying, place the 500g weight on gauze, evaluated in resistance when peeling off the gauze after 1 hour.

<Evaluation criteria>
○: Level with almost no resistance.
(Triangle | delta): There is considerable resistance and it is the level which a worker's footwear and clothes are expected to get a little dirty.
X: A level at which there is a great resistance and the worker's footwear and clothes are expected to be considerably dirty.

Claims (5)

The organic solvent comprising a copolymer solution or dispersion containing a hydroxyl group-containing vinyl copolymer (A) having a polyester segment (A), a polyalkylene glycol (B) and an organic solvent (C) and a polyisocyanate (D). 20 parts by weight or more of (C) is an aliphatic hydrocarbon solvent, and the polyalkylene glycol (B) is dissolved in the organic solvent (C). The two-component coating composition according to claim 1, wherein a weight ratio of the polyester segment in the hydroxyl group-containing vinyl copolymer (A) having the polyester segment is 1 to 50% by weight. The hydroxyl group-containing vinyl copolymer (A) having the polyester segment comprises a polyester segment and a hydroxyl group-containing vinyl polymer segment, and the glass transition temperature determined by the Fox formula of the hydroxyl group-containing vinyl polymer segment is 20 ° C. The two-component coating composition according to claim 1, which is as described above. The two-component coating composition according to claim 1, wherein the hydroxyl group-containing vinyl copolymer (A) having the polyester segment has a hydroxyl value of 10 to 100. The two-component coating composition according to claim 1, wherein the content of the polyalkylene glycol (B) is 0.5 to 10% by weight based on the hydroxyl group-containing vinyl copolymer (A) having the polyester segment. .