JPH0127108B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel coating composition, and more particularly to a coating composition containing a vinyl copolymer modified with cellulose acetate butyrate and a polyisocyanate compound and having particularly excellent gloss and texture. Traditionally, acrylic lacquer, acrylic enamel, and acrylic urethane paints have been mainly used when repairing automobiles, industrial machinery, buildings, structures, furniture (including steel), etc. Paints have various defects, and improvement of these defects is strongly desired. for example,
Acrylic lacquer is a paint whose vehicle main component is a cold blend of acrylic resin and nitrocellulose or cellulose acetate butyrate. Even within the composition range, the paint film formed from the lacquer is prone to cracking during outdoor exposure, and the paint film has poor texture and texture, requiring polishing to smooth the paint film. It has drawbacks such as the need for many steps to achieve a nice painted surface. In addition, acrylic enamel has acrylic resin as its main vehicle component, but
The coating film formed from this enamel has hardness, solvent resistance,
Acrylic urethane paints have drawbacks such as insufficient chemical resistance and durability, and although the main vehicle components of acrylic urethane paints are acrylic resin and polyisocyanate compounds, the drying properties of the paint film are poor. It is also known to further add nitrocellulose or cellulose acetate butyrate to the lacquer, but in this case, as in the case of the acrylic lacquer, there are problems with the compatibility, the texture of the paint film, the texture, etc. This is not preferable because it causes Therefore, in view of the above situation, the present inventors
It cures quickly at room temperature, and can form a smooth painted surface with gloss and excellent texture just by painting without polishing.It is also highly durable and can be exposed to the outdoors for a long time. We have worked diligently to develop coating compositions that do not crack even when exposed to water and provide coatings with excellent water resistance, adhesion, gasoline resistance, weather resistance, chemical resistance, solvent resistance, etc. As a result of our research, we found that a modified vinyl copolymer obtained by copolymerizing cellulose acetate butyrate with a vinyl monomer mixture containing a vinyl monomer having a hydroxyl group and a lower alkyl ester of acrylic acid or methacrylic acid was used as the main vehicle. It was discovered that the above object could be achieved by using a polyisocyanate compound as a curing agent component and a polyisocyanate compound as a curing agent component, and by combining the two, and completed the present invention. Thus, according to the present invention, [] (a) cellulose acetate butyrate 5-
(b) (i) 1 to 50% by weight of at least one functional vinyl monomer containing a hydroxyl group; and (ii) C ₁ of acrylic acid or methacrylic acid.
~At least one _C5 alkyl ester,
or acrylic acid or methacrylic acid
At least _one C1- _C5 alkyl ester
mixtures of at least one copolymerizable vinyl monomer other than alkyl esters of acrylic acid or methacrylic acid 99
A modified vinyl copolymer obtained by copolymerizing 95-25% by weight of a vinyl monomer mixture consisting of ~50% by weight, and [] a polyisocyanate compound having two or more free isocyanate groups in one molecule. There is provided a coating composition characterized in that the main component is: Hereinafter, the coating composition of the present invention will be explained in more detail. [] Modified vinyl copolymer (a) Cellulose acetate butyrate Cellulose acetate butyrate (hereinafter referred to as
(abbreviated as "CAB") is a cellulose derivative obtained by further butyl esterification of partially acetylated cellulose, and CAB that can be preferably used in the present invention generally has an acetyl group content of 1 to 30% by weight. , preferably 1-14% by weight
, the butyl group content is generally 16-60% by weight, preferably 35-60% by weight, and the ASTM-
The viscosity when measured by the viscosity measurement method described in D1343-54T (Formula A) is generally 0.005~
5 seconds, preferably in the range of 0.005 to 1 second. Specifically, products manufactured by Eastman Kodatsu Co., Ltd. in the United States, such as product names (the second digit of the former number is the butyl group content (wt%))
, the third digit also indicates the hydroxyl group content, and the latter number indicates the viscosity (seconds)], and the EAB
-171-2, EAB-381-0.5, EAB-381-2,
EAB-531-1, EAB-551-0.2, EAB-551-
Grades such as 0.01 are advantageously used, and EAB
―381―0.5, EAB―551―0.2 and EAB―551―
0.01 is particularly preferred. (b) Vinyl monomer mixture The vinyl monomer mixture to be copolymerized with CAB according to the invention comprises at least a functional vinyl monomer containing a hydroxyl group and a C ₁ -C ₅ alkyl ester of acrylic acid or methacrylic acid, thereby resulting in the modification obtained. A functional group (hydroxyl group) can be introduced into the vinyl copolymer. Examples of the functional vinyl monomer containing a hydroxyl group (hereinafter abbreviated as a hydroxyl group-containing vinyl monomer) include acrylic acid or methacrylic acid such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, and hydroxypropyl methacrylate. C ₂ - C ₂₄ hydroxyalkyl esters of Examples include mono- or di-C ₁ -C ₁₂ hydroxyalkylamides of acrylic acid or methacrylic acid such as. The above hydroxyl group-containing vinyl monomer may be used alone or in combination.
Combinations of one or more species can be used. In addition, examples of the C ₁ to _{C 5} alkyl ester of acrylic acid or methacrylic acid used in combination with the above-mentioned hydroxyl group-containing vinyl monomer include:
Methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-
Examples include butyl acrylate, n-butyl methacrylate, i-butyl acrylate, i-butyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, and these can be used alone or in combination of two or more types. . On the other hand, other copolymerizable vinyl monomers other than those mentioned above to be used in combination with the hydroxyl group-containing vinyl monomer contain 1 to 2, preferably only 1, radically polymerizable α,β-ethylenically unsaturated bond. For example, the following compounds (A) to (C) are preferably used.
One or more of these can be appropriately selected and used. (A) Vinyl aromatic compounds such as styrene, vinyltoluene, α-methylstyrene, or other vinyl monomers such as vinyl acetate, acrylonitrile, methacrylonitrile; (B) Acrylamide, methacrylamide, N-methylacrylamide, N-ethyl methacrylamide, N,N-dimethylacrylamide, N,
Acrylic or methacrylamide such as N-diethylmethacrylamide. (C) Glycidyl vinyl ethers, glycidyl methyl acrylate, such as glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, methacryl glycidyl ether,
Glycidyl group-containing vinyl monomers such as glycidyl methyl methacrylate. These other copolymerizable vinyl monomers can be used alone, or two or more types can be used in combination. Among these vinyl monomers, 2-hydroxyethyl methacrylate is used as a hydroxyl group-containing vinyl monomer, and other copolymerizable vinyl monomers include styrene and C ₁ -C ₅ alkyl esters of acrylic acid or methacrylic acid, such as methyl acrylate, methyl methacrylate. , ethyl acrylate, ethyl methacrylate, n-butyl acrylate, n-butyl methacrylate, etc. are suitable. In particular, when styrene, another vinyl monomer, is contained in an amount of 5 to 35% by weight based on the total weight of the vinyl monomer mixture, the chemical resistance, adhesion, etc. of the coating film are further improved. According to the invention, when these other copolymerizable vinyl monomers are used in combination with the hydroxyl-containing vinyl monomer, the hydroxyl-containing vinyl monomer is present in an amount of 1 to 50% by weight, based on the total weight of the vinyl monomer mixture. , preferably 5 to 35% by weight, and therefore the remaining 99 to 50% by weight,
Preferably, 95 to 65% by weight can be the other copolymerizable vinyl monomer. If the proportion of the hydroxyl group-containing vinyl monomer in the vinyl monomer mixture is less than 1% by weight, the crosslinking reaction of the formed coating film will be insufficient, resulting in poor gasoline resistance, solvent resistance, chemical resistance, water resistance, etc. On the other hand,
When the amount exceeds 50% by weight, the coating film becomes brittle and chemical resistance, water resistance, weather resistance, etc. decrease. Furthermore, in the present invention, a carboxyl group-containing vinyl monomer can be used in combination with the vinyl monomer mixture for the purpose of improving adhesion, flexibility, pigment dispersibility, compatibility, and the like. Examples of the carboxyl group-containing vinyl monomer include C ₃ to C ₆ unsaturated fats such as acrylic acid, methacrylic acid, vinyl acetic acid, itaconic acid, crotonic acid, maleic acid, maleic anhydride, fumaric acid, citraconic acid, and mesaconic acid. Family- or dibasic acids are preferred. The amount of the carboxyl group-containing vinyl monomer used is 5% by weight or less, based on the total amount (vinyl monomer mixture) of the hydroxyl group-containing vinyl monomer, the other copolymerizable vinyl monomer, and the carboxyl group-containing vinyl monomer, Preferably
The content is 0.2 to 2% by weight, and if it exceeds 5% by weight, water resistance, storage stability, etc. will decrease. Copolymerization The modified vinyl copolymer used as the main component of the vehicle in the present invention can be obtained by copolymerizing the above-mentioned CAB and the above-mentioned vinyl monomer mixture. The copolymerization ratio of CAB and vinyl monomer mixture can be varied depending on the composition of the vinyl monomer mixture used and its ratio, but generally, based on the total amount of CAB and the vinyl monomer mixture, CAB is 5-75% by weight, preferably 10-50% by weight, more preferably 30-50% by weight
The vinyl monomer mixture is blended within the range of
It can be blended in an amount of 95 to 25% by weight, preferably 90 to 50% by weight, and more preferably 70 to 50% by weight. If the blending amount of CAB is less than 5% by weight, defects such as those in acrylic enamel will occur, and the hardness, solvent resistance, chemical resistance, durability, etc. of the coating film will deteriorate, and if it exceeds 75% by weight, the coating surface will deteriorate. There is a tendency for skin irritation to occur and also for a decrease in adhesion. The copolymerization of CAB and the above-mentioned vinyl monomer mixture is advantageously carried out by a solution polymerization method in the presence of a radical polymerization initiator. Examples of solvents that can be used in the solution polymerization include alkylbenzene derivatives such as benzene, toluene, and xylene;
Butyl acetate, ethyl acetate, propyl acetate, amyl acetate, methoxybutyl acetate, methyl acetoacetate,
Acetate ester solvents such as ethyl acetoacetate, methyl cellosolve acetate, cellosolve acetate, diethylene glycol monomethyl acetate, and carbitol acetate; Ether solvents such as dioxane, ethylene glycol diethyl ether, ethylene glycol butyl ether, diethylene glycol diethyl ether; acetone, methyl ethyl ketone, Examples include ketone solvents such as methyl isobutyl ketone, and these may be used alone or in combination of two or more. Additionally, the polymerization temperature can generally range from about 50 to about 200°C, preferably from about 80 to about 150°C. Examples of the radical polymerization initiator include organic peroxide type initiators, such as peroxide polymerization initiators such as benzoyl peroxide, lauroyl peroxide, dicumyl peroxide, etc., and tert-butyl hydroperoxide, cumene hydroperoxide, etc. Hydroperoxide-based polymerization initiators such as the following are preferably used, and ketone peroxide-based and perester-based polymerization initiators can also be used. These polymerization initiators are added to the polymerization reaction system either alone or in combination of two or more. Furthermore, in addition to the above-mentioned peroxides, hydroperoxides, etc., an azo polymerization initiator such as azobisiso-butyronitrile may be used in combination. especially,
Benzoyl peroxide is preferred. In copolymerization reactions using organic peroxides as polymerization initiators as described above, free radicals of organic compounds generated by thermal decomposition of these polymerization initiators generally cause so-called chain transfer to hydrocarbon compounds. It is thought that the free radicals generated on the hydrocarbon compound initiate polymerization of the vinyl monomer, and the vinyl monomer grows in a branched form on the hydrocarbon compound, forming a graft copolymer. In the copolymerization of the present invention using CAB and a vinyl monomer mixture, it is thought that a graft copolymer of CAB and a vinyl monomer mixture is formed by such a reaction mechanism. The modified vinyl copolymer thus formed, ie, the CAB graft copolymer, has excellent solubility in organic solvents and compatibility with other resins. In the present invention, it is desirable that substantially all of the blended CAB be copolymerized with the vinyl monomer mixture, but a small amount of CAB and/or the vinyl monomer mixture may remain unreacted in the copolymer. There is no problem even if it remains. [] Polyisocyanate compound In the coating composition of the present invention, the polyisocyanate compound that acts as a curing agent for the modified vinyl copolymer is a compound known per se, and contains free isocyanate groups in one molecule. It is a compound having 2 or more, preferably 2 to 3. That is, (1) a diisocyanate compound, (2) a triisocyanate compound, and (3) an isocyanate addition having two or more terminal isocyanate groups in one molecule, which is obtained by reacting the di- or triisocyanate compound with an active hydrogen-containing compound. Examples include things. The polyisocyanate compounds belonging to (1) to (3) above easily react with the modified vinyl copolymer and cure, so they are suitable when the coating composition of the present invention is used as a room-temperature curing type. . Examples of diisocyanate compounds and triisocyanate compounds belonging to (1) and (2) above include tetramethylene diisocyanate, hexamethylene diisocyanate, decamethylene diisocyanate, ethylene diisocyanate, propylene diisocyanate, isophorone diisocyanate, isophorone diamine diisocyanate, lysine diisocyanate, dimer Aliphatic isocyanates such as acid diisocyanate, xylylene diisocyanate, methylxylylene diisocyanate, phenylene diisocyanate, tolylene diisocyanate, naphthylene diisocyanate, 4,4'-methylenebis(phenyl isocyanate), 4,4'-ethylenebis( phenyl isocyanate), 3,3'-diisocyanate 1,4 dimethylbenzene, 3,3'-diisocyanate diethylbenzene, 3,3'-diisocyanate dimethyltoluene, 3,3'-diisocyanate diethyltoluene, 3,3'-diisocyanate dimethyl Aromatic isocyanates such as xylene, 3,3'-diisocyanate diethylxylene, triphenylmethane diisocyanate, diphenylmethane diisocyanate, metaphenylene diisocyanate, diphenylmethane triisocyanate, and 1-methyl-2,4 diisocyanate cyclohexanone, 4 , 4'-methylene bis(cyclohexyl isocyanate), ethylene bis(cyclohexyl isocyanate), and alicyclic isocyanates such as cyclohexane diisocyanate. Moreover, the polyisocyanate compound belonging to the above (3) is obtained by reacting the above di- or triisocyanate compound with an active hydrogen-containing compound.
isocyanate adducts having at least 1, preferably 2 to 3 terminal free isocyanate groups.
Examples of the active hydrogen-containing compound include ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, 2,2,
4-trimethyl 1,3 pentadiol, hexamethylene glycol, cyclohexanedimethanol,
trimethylolpropane, hexanetriol,
Examples include glycerin, pentaerythritol sorbitol, sucrose, castor oil, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, hexamethylenediamine, water, polyether polyol, polyester polyol, polyamide, and hydroxyl group-containing acrylic resin. The addition reaction between these di- or triisocyanate compounds and the active hydrogen-containing compound can be carried out by a known method. The polycyanate compounds belonging to the above (1) to (3) are suitable when the coating composition of the present invention is used as a room-temperature curing type, and these may be used singly or in combination.
More than one species can be used in combination, but among these, the above (3)
It is preferable to use polyisocyanate compounds (isocyanate adducts) belonging to the above group because of their low toxicity and the moderate evolution of the curing reaction with the modified vinyl copolymer. Among them, adducts of hexamethylene diisocyanate or xylene diisocyanate and water or polyhydric alcohols have a relatively long pot life, and
It is suitable because it has excellent painting workability. Preparation of Coating Composition The coating composition of the present invention can be prepared by mixing the above-mentioned modified vinyl copolymer and polyisocyanate compound in the presence of an appropriate solvent, if necessary. At this time, the mixing ratio of the modified vinyl copolymer and the polyisocyanate compound is preferably 0.3 to 2.0 moles of free isocyanate groups contained in the polyisocyanate compound per 1 mole of hydroxyl groups contained in the modified vinyl copolymer. is 0.5 to 1.5 mol, more preferably 0.8 to 1.5 mol
It is within the range of 1.2 moles. The isocyanate group is
If the amount is less than 0.3 mol, the curing properties of the coating film formed will be insufficient, resulting in poor gasoline resistance, solvent resistance,
Chemical resistance will decrease, and if the amount exceeds 2.0 mol, curing (crosslinking) with the modified vinyl copolymer will occur.
Since the reaction occurs rapidly, painting work becomes complicated,
Moreover, the flexibility, texture, texture, durability, etc. of the coating film are deteriorated, so all of these are unfavorable. Furthermore, since the above-mentioned modified vinyl copolymer has excellent compatibility with other resins as described above, the coating composition of the present invention utilizes this property to improve the physical properties of the coating film. For the purpose of improvement and cost reduction, etc.
Other paint resins commonly used in paints, such as acrylic resins, cellulose derivatives, acrylic graft alkyd resins, alkyd resins, petroleum resins, natural resins, etc., can be included. These coating resins may contain hydroxyl groups that react with isocyanate groups, but in that case, the above-mentioned blending ratio of the polyisocyanate compound should be the same as that of the modified vinyl copolymer and the coating resin. It refers to the total amount of hydroxyl groups contained per mole. In the coating composition of the present invention, any conventional organic solvent for paints can be used as necessary, but from the viewpoint of improving the storage stability of the composition, organic solvents that do not have hydroxyl groups are preferred. It is preferable to use For example, ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, methyl hexyl ketone and cyclohexanone, or methyl acetate, ethyl acetate, butyl acetate, propyl acetate, amyl acetate,
Methoxybutyl acetate, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl ether acetate (methyl cellosolve acetate), ethylene glycol monoethyl acetate (cellosolve acetate), butyl cellosolve acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl acetate, etc. Use ester solvents as true solvents, and use heptane,
Hydrocarbon solvents such as octane, methylcyclohexane, toluene, and xylene may be used as diluting solvents. The amount of these true solvents used is preferably about 40% by weight or more based on the total solvent. Furthermore, the coating composition of the present invention may contain colorants (e.g., inorganic or organic colorants such as titanium white, carbon black, red iron, yellow lead, deep blue, ultramarine, etc.), extender pigments (e.g., talc, clay,
Calcium carbonate, mica, etc.), metallic pigments (e.g. metal powders such as aluminum powder, copper powder, bronze powder, titanium dioxide coating, micaceous iron oxide, nickel sulfide powder, cobalt sulfide powder, manganese sulfide powder, titanium nitrogen powder, etc.) Metal compound powder) etc. may be contained alone or in combination. The coating composition of the present invention can be prepared by mixing and dispersing the above-mentioned components in a conventional manner. That is, polyisocyanate compounds having free isocyanate groups (compounds and adducts belonging to (1) to (3) above) easily react and cure with modified vinyl copolymers at room temperature. It is preferable to separate it from the modified vinyl copolymer in advance, mix and dilute it immediately before coating, and use it (coating) in a so-called two-component form. For example, the two components, which have a solid content of about 20 to 80% by weight, preferably 35 to 75% by weight, are separated in advance, and other paint resins, pigments, solvents, various additives, etc. are added as necessary. is mixed and dispersed in either or both of the two components, and then the two components are mixed immediately before painting to obtain a solid content of approximately 20 to 20%.
It is preferable to prepare it to 80% by weight and then apply it to the coating. In this case, immediately before painting means within one week, preferably three days prior to the time of painting.
It refers to a period of less than one day, more preferably one day or less. The dryness of the paint film painted in this way is 20
C. for about 5 to 10 minutes, and curing and drying at the same temperature for about 30 to 40 minutes, but if necessary, curing can be accelerated by heating to a temperature of 80.degree. C. or lower. Since this two-component paint hardens quickly even at room temperature, it is preferably applied to objects to be coated that are difficult or impossible to heat. The coating composition of the present invention can be diluted with a solvent if necessary during use, so that the organic solvent content is generally 80 to 20% by weight, especially when applied.
From the viewpoint of painting workability, it is desirable that the content be 70 to 35% by weight. The coating composition of the present invention is applied according to a conventional method,
For example, air spraying, airless spraying, electrostatic coating, brush coating, roller coating, dip coating, etc. can be used, and it is particularly preferable that the dry coating film thickness is in the range of about 5 to 100 μm. The coating composition of the present invention can be applied to any material or amount without particular limitation, and can be used to coat various materials, such as metals (iron, aluminum, alloys containing these, etc.), wood, glass, plastics, etc. Examples include substrates coated with organic or inorganic coatings. As mentioned above, the characteristics of the coating composition of the present invention are that a graft copolymer (modified vinyl copolymer) containing CAB and a polyisocyanate compound are used in combination, and as a result, as described below, We were able to achieve such excellent technical effects. First, in the coating composition of the present invention, since the modified vinyl copolymer contained therein is formed by copolymerizing CAB and the specific vinyl monomer mixture, CAB and the vinyl resin are each It is possible to simultaneously and fully exhibit the advantages of both CABs, such as the excellent curability, solvent release resistance, gasoline resistance, and weather resistance of CAB, and the excellent coating surface texture and properties of vinyl resins. Properties such as adhesion work together to provide a coating film with excellent coating performance. It is difficult to use both of the above components together due to their poor compatibility, and even if they were compatible, the performance of the coating formed using the mixture would be extremely insufficient and would not be practically satisfactory. However, by using a modified vinyl copolymer obtained by graft polymerization as described above, the above-mentioned technical effects could be achieved, and it can be said to be a groundbreaking work. . Further, since the composition of the present invention uses the modified vinyl copolymer together with a polyisocyanate compound, it has the ability to form a three-dimensionally crosslinked and cured coating film even at room temperature. As a result, various properties of the coating film, such as hardness, flexibility, water resistance, weather resistance, solvent resistance, and chemical resistance, can also be significantly improved. It also has excellent adhesion to the old top coat, and is a highly practical paint that does not cause any abnormalities to the paint film. Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. Note that all parts and % indicate parts by weight and % by weight. Production Example of Modified Vinyl Copolymer Solution 1 The following ingredients are charged into a reactor equipped with a thermometer, a stirrer, a reflux condenser, and a dropping funnel. Toluene 30 parts Butyl cellosolve acetate 20 parts EAB-551-0.2 (CAB manufactured by Eastman Kodatsu) 50 parts Total 100 parts The above mixture is heated under a nitrogen gas atmosphere to 100°C for about 1 hour or more. After confirming that the temperature reached 100℃ and that the CAB was completely dissolved,
A mixture of a vinyl monomer mixture and a polymerization initiator shown below is added dropwise to the CAB solution over a period of 3 hours. 2-Hydroxyethyl methacrylate 12 parts Acrylic acid 1 part Styrene 20 parts Methyl methacrylate 20 parts Ethyl acrylate 47 parts Xylol 50 parts Benzoyl peroxide 2 parts Total 152 parts 30 minutes after the completion of dropping, add 0.5 part of azobisisobutyronitrile, Further, for 2 hours under nitrogen atmosphere, 100
C., and then xylol was added to obtain a modified vinyl copolymer solution A with a solid content of 50%. The copolymer solution was clear and colorless. Production Examples 2 to 17 Modified vinyl copolymer solutions B to Q with a solid content of 50% were produced using the same production method as for modified vinyl copolymer solution A in Production Example 1. Composition of vinyl monomer mixture in each copolymer solution, and CAB
(EAB-551-0.2 or EAB-381-0.5 manufactured by Eastman Kodak) is shown in Table 1, including Production Example 1. In addition, among the following copolymer solutions,
K to Q are for comparative tests.

【table】

[Table] (a) 2-ethylhexyl methacrylate
(b) Lauryl methacrylate Example 1 To 100 parts of the 50% modified vinyl copolymer solution A obtained in Production Example 1, 10 parts of methyl cellosolve acetate, 10 parts of toluene, and 10 parts of xylol were added, and the mixture was heated with a disper for 5 minutes. While stirring, 10 parts of Takenate D110N (trade name of Takeda Pharmaceutical Co., Ltd., xylene diisocyanate adduct) was added and mixed to obtain a coating composition with a solid content of 42%. Examples 2 to 16, Comparative Examples 1 to 15 Coating compositions were obtained in the same manner as in Example 1 based on the formulations shown in Tables 2 and 3.

【table】

【table】

【table】

【table】

〔Test results〕

Various performance tests were conducted on the coating compositions obtained in Examples 1 to 16 and Comparative Examples 1 to 15. The results are shown in Table 4 (1) and (2). The test methods in Table 4 (1) and (2) are as follows. (1) Dry to the touch time: After applying the paint to a glass plate with a doctor blade in a constant temperature and humidity room at a temperature of 20°C and humidity of 75% to a thickness of about 100μ, touch it with your finger until the paint is dry to the touch. The time until it stopped adhering to the surface (touch dry time) was measured. (2) Pencil hardness: After painting in the same manner as in (1) above and leaving it at 20℃ for 24 hours,
A pencil scratch test was conducted at the same temperature to determine the hardness of the pencil that would cause the paint film to break. The pencil used was a daily-tested pencil scratch value test. (3) Gloss: Apply an alkyd-modified lacquer-based primer (“Campe Plasaf Gray” Kansai Paint Co., Ltd. product name) to a mild steel plate by air spraying to a dry film thickness of 40 μm, and dry at 20°C for 1 hour. After that, an acrylic lacquer topcoat (“Acrylic No. 1531 White” Kansai Paint Co., Ltd. product name) was applied to a dry film thickness of 50 μm.
The coated surface was coated in layers until it was dry for 7 days at 20°C, and then sanded with #400 waterproof paper until the coated surface was smooth. The paints obtained in the above Examples and Comparative Examples were applied to the thus obtained coating film using air spray so that the dry film thickness was 50μ, and the 60 degree specular reflectance was measured after standing at 20°C for 24 hours. did. (4) Painted surface: The condition of the painted surface of the painted board prepared in the same manner as in (3) above was visually determined. (5) Gasoline resistance: A coated plate prepared in the same manner as in (3) above was immersed in regular type gasoline at 20°C for 10 hours and the condition of the coated surface was examined. (6) Toluene resistance: A coated plate prepared in the same manner as in (3) above was immersed in toluene at 20°C for 10 hours, and then the condition of the coated surface was examined. (7) Alkali resistance: A coated plate prepared in the same manner as in (3) above was heated to 3% at 20°C.
The condition of the painted surface was examined after immersion in NaOH aqueous solution for 24 hours. (8) Acid resistance: A coated plate prepared in the same manner as in (3) above was heated to 5% at 20°C.
After being immersed in an HCI aqueous solution for 24 hours, the condition of the painted surface was examined. (9) Water resistance: A coated plate prepared in the same manner as in (3) above was immersed in tap water at 20°C for 7 hours, and then the condition of the coated surface was examined. (10) Adhesion: Perform the same procedure as in (9) above, remove from the water, immediately wipe off the water with a cloth, cross-cut with a knife on the diagonal of the coated plate so as to reach the substrate, and perform a peeling test with adhesive tape. Ta. (11) Accelerated weather resistance: The results of a 500-hour sunshine weather meter test on a coated plate prepared in the same manner as in (3) above are shown. (12) Cracking resistance: A coated board prepared in the same manner as in (3) above was left at 70°C for 1 hour → immersed in tap water at 20°C for 1 hour → −
A test in which one cycle was ``Leave it at 20℃ for 1 hour.''
The condition of the painted surface was examined after 20 consecutive cycles.

【table】

【table】

【table】

Claims (1)

[Scope of Claims] 1 [] (a) 5 to 75% by weight of cellulose acetate butyrate, and (b) 1 to 50% by weight of at least one of (i) a functional vinyl monomer containing a hydroxyl group, and (ii) C ₁ of acrylic acid or methacrylic acid
~At least one _C5 alkyl ester,
or acrylic acid or methacrylic acid
At least _one C1- _C5 alkyl ester
A mixture of at least one copolymerizable vinyl monomer other than an alkyl ester of acrylic acid or methacrylic acid99~
A transparent solution of a modified vinyl thread copolymer obtained by copolymerizing 95 to 25% by weight of a vinyl monomer mixture consisting of 50% by weight, and [] a polyisocyanate having two or more free isocyanate groups in one molecule. A coating composition curable at room temperature, characterized by comprising a compound. 2 The cellulose acetate butyrate is 1-
With an acetyl group content of 30% by weight and a butyl group content of 16-60% by weight, and ASTM-D1343-54T
The coating composition according to claim 1, which has a viscosity of 0.005 to 5 seconds as measured according to the method described in (Formula A). 3. The coating composition according to claim 1 or 2, wherein the vinyl monomer mixture contains 0 to 5% by weight of a carboxyl group-containing vinyl monomer. 4. A coating composition according to any one of claims 1 to 3, wherein the copolymerization is carried out by solution polymerization at a temperature of about 50 to about 200°C. 5. The polyisocyanate compound is a diisocyanate compound, a triisocyanate compound, or an isocyanate adduct having two or more free isocyanate groups in one molecule produced by the reaction of the di- or triisocyanate compound with an active hydrogen-containing compound. Certain claims 1st to 4th
The coating composition according to any one of paragraphs. 6 The mixing ratio of the modified vinyl copolymer and the polyisocyanate compound is such that the free isocyanate group of the latter is equal to 1 mole of hydroxyl group contained in the former.
Claims 1 to 2 are in the range of 0.3 to 2.0 moles.
Coating composition according to any one of Item 5.