JPS60250072A - Coating composition for building material - Google Patents

Abstract

PURPOSE:To provide the titled coating compsn. contg. a modified acrylic copolymer obtained by addition reaction of a fatty acid with a specified epoxy group- contg. acrylic copolymer and having high penetrating power and excellent resistance to alkali and solvent. CONSTITUTION:A modified acrylic copolymer is prepd. by addition reaction of (A) 100pts.wt. epoxy group-contg. acrylic copolymer obtained by copolymerization of 0-60wt% aromatic vinyl monomer (e.g. styrene), 5-25wt% epoxy group- contg. vinyl monomer [e.g. glycidyl (method)acrylate] and 0-10wt% alkyd resin having compolymerizable unsatd. bonds, with (B) 5-60pts.wt. fatty acid having an iodine value of below 100 (e.g. soybean oil). The coating compsn. is obtained by blending the copolymer, a drier for paint, a levelling agent, an organic peroxide, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION (Object of the Invention) The present invention relates to a primer for building materials that has good permeability, alkali resistance, and solvent resistance, and a top coat for building materials that has good weather resistance, gloss, and physical properties.

[Industrial application field]

When painting alkaline inorganic materials such as cement, slate, and mortar, it is common to apply a primer (sealer) to prevent deterioration of the intermediate coat and top coat by sealing out the alkali that flows out from those materials. It is.

The required performance of these primers is alkali resistance,
It should have good water resistance, be unaffected by the solvent if a solvent-based paint is used for the top coat, and have good glabellar adhesion with the intermediate coat and/or top coat.

Recently, external walls,
There is a need for a so-called penetrating sealer, which can be applied to defective areas such as minor cracks and peeling in inner walls, etc., so that the sealer penetrates into the defective areas and stops deterioration. In order to impart permeability, it is effective to lower the molecular weight and/or tg, but resins with lower molecular weight and tg usually have significantly lower alkali resistance and solvent resistance. .

On the other hand, as top coats for building materials, one-component, one-component or two-component isocyanate-cured acrylic paints, such as vinyl acetate-acrylic paints and acrylic-styrene paints, are widely used. Although two-component paints have very good performance, they have problems in terms of workability, toxicity, and cost. Raccata.

Although Eve is generally inexpensive, since it is not a crosslinked three-dimensional coating film, it has always been poor in performance, particularly in weather resistance, graininess, and adhesion.

〔Effect of the invention〕

As a result of intensive studies in view of these points, the inventors found that modified acrylic copolymers obtained by adding fatty acids to epoxy group-containing copolymers have good dilutability with solvents, and that when the molecular weight is set to a certain low level, It has better permeability than conventional lacquer resins, and because the unsaturated bonds contained in the fatty acids of the modified acrylic copolymer undergo oxidative polymerization,
In order to provide a strong coating film with high molecular weight, we discovered that it is ideal as a sealer because it has good water resistance, alkali resistance, and solvent resistance, and also has good interlayer adhesion with intermediate coatings such as emulsion light. Ta. Furthermore, we have discovered that when the modified acrylic copolymer is used as a top coat resin for building materials, it has good weather resistance and grain resistance due to oxidative polymerization, and has a much better gloss than conventional acrylic lacquers. The present invention has now been completed. Additionally, since hydroxyl groups are generated in the step of adding fatty acids to the epoxy group-containing copolymer, urethane crosslinking can be achieved by blending polyisocyanate, and the two crosslinking reactions of oxidative polymerization crosslinking and urethane crosslinking using a dryer can be performed. They can also be used together.

[Prior art]

By the way, a method of obtaining an air-curable resin by adding a drying oil fatty acid to such an epoxy group-containing acrylic copolymer has already been disclosed in British Patent No. 767,476, and the method of obtaining an air-curable resin by such a method has already been disclosed. In order to solve the problem of insufficient gloss due to insufficient wetting of the resin to the pigment, improvement methods as described in JP-A-53-51233 and JP-A-53-99231, respectively, have been proposed.

However, in all of the above improvement methods, fi+ A total reaction consisting of three steps: production of an acrylic copolymer, (2) addition of a drying oil fatty acid to the copolymer, and (3) esterification of the fatty acid-modified copolymer with dicarboxylic anhydride. This method cannot be said to be a preferable method because it lengthens the time and complicates reaction control, leading to increased production costs.

[Structure of the invention]

In view of the above-mentioned circumstances, the present inventors obtained a fatty acid-modified acrylic copolymer with good pigment wettability and excellent gloss using a simpler method.

That is, the present invention uses 0 to 60% by weight of an aromatic vinyl monomer and 5 to 25% by weight of an epoxy group-containing vinyl monomer.
, 0 to 10% by weight of alkyds having copolymerizable unsaturated bonds and other vinyl monomers copolymerizable with these 5
Modified acrylic copolymer obtained by copolymerizing ~95% by weight and then adding-reacting fatty acid at a ratio of 5 to 60 parts by weight to 100 parts by weight of the epoxy group-containing acrylic copolymer thus obtained. The present invention provides a coating composition for building materials that includes a coating composition.

Typical fatty acids used in the present invention include drying oil fatty acids of natural oils such as cottonseed oil, soybean oil, rice bran oil, dehydrated castor oil, linseed oil, tall oil, or Chinese tung oil; Hygiene H”, “Hidiene S”, rsK conjugated fatty acid #20J (all Soken Chemical products) or [PAMOLYN 200
．． Synthetic drying oil fatty acids such as 300J (product of Percules, USA), or coconut oil fatty acids, castor oil fatty acids,
Octylic acid, lauric acid, "persatic acid" (synthetic drying oil fatty acids manufactured by Shell in the Netherlands), stearic acid or human waxy stearic acid with an iodine value of 10
There are less than 0 fatty acids and saturated fatty acids, but these semi-drying oils, non-drying oils, and saturated fatty acids can of course be used in combination with the above-mentioned drying oil fatty acids.

The appropriate amount of the fatty acid used is 5 to 60 parts by weight, preferably 10 to 50 parts by weight, based on 100 parts by weight of the epoxy group-containing vinyl copolymer.

If the amount used is less than 5 parts by weight, physical properties and solvent resistance will deteriorate; if it exceeds 60 parts by weight, yellowing may occur easily and weather resistance may deteriorate. Moreover, as a result of excessive crosslinking of the resulting coating film, flexibility is impaired and the coating film becomes brittle, making it impossible to put it into practical use.

Next, the epoxy group-containing vinyl copolymer described above will be described. Typical epoxy group-containing vinyl monomers include glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, or (meth)allyl glycidyl ether, as well as (meth)acrylic acid, fumaric acid, maleic acid, and itacon. Unsaturated monomers such as acids or dicarboxylic acids, or α,β-ethylenically unsaturated carboxylic acids such as monoesters of such unsaturated dicarboxylic acids and monohydric alcohols, rHOA
Carboxyl group-containing compounds such as -MPJ or rHOA-H3J (carboxyl group-containing acrylic monomer manufactured by Osaka Organic Chemical Company), or mono-2-(
Hydroxyl group-containing vinyl monomers such as meth)acryloyloxyethyl phthalate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate or di-2-hydroxyethyl fumarate, and maleic acid, phthalic acid, tetrahydrophthalic acid, Obtained by equimolar addition reaction with polycarboxylic acids (anhydrides) such as hexahydrophthalic acid, benzenetricarboxylic acid, "Himic acid" [Hitachi Chemical product], dodecynylsuccinic acid, succinic acid or tetrachlorophthalic acid. Various unsaturated forces such as additives! To levonic acid, [Ebikuloa 200.400.441.850 or 10
50J (epoxy resin manufactured by Dainippon Ink & Chemicals)
, [Epicote 828.1001 or 1004J
(epoxy resin manufactured by Shell), [Araldite 6o7
1 or 6084J (epoxy resin manufactured by Ciba Geigy, Switzerland), [Chissonox 221J (epoxy compound manufactured by Chisso ■) or [Bunacol EX-8
1, such as 10J (epoxy compound manufactured by Nagashio Sangyo ■)
There are epoxy group-containing polymerizable compounds obtained by addition-reacting various polyepoxy compounds having at least two epoxy groups in the molecule in equimolar ratios, and these can be used alone or in combination of two or more. However, considering reactivity, number of reaction steps, viscosity or price of the final product, relatively low molecular weight types such as glycidyl (meth)acrylate and β-methylglycidyl (meth)acrylate are recommended. Monomers are the easiest to use.

The epoxy group-containing vinyl monomer is used in a range of 5 to 25% by weight, but although the epoxy group in the monomer participates in the reaction with the fatty acid as mentioned above, the amount of the monomer used is mainly It goes without saying that the amount should be determined depending on the amount of fatty acid used, but it is usually 1.0 to 1 per equivalent of fatty acid carboxyl group.
．． It is preferable to use the epoxy group in a proportion of 25 equivalents from the viewpoint of reaction rate and the possibility of preventing the adverse effects of residual carboxyl groups on the coating film.

In addition, the above-mentioned alkyd resins having copolymerizable unsaturated bonds can be used not only for pigments with low oil absorption such as titanium oxide and Bengara, but also for TMR pigments such as quinacridone, phthalocyanine, and azo. It is used when it is desired to improve the dispersibility of pigments with relatively large oil absorption and poor dispersibility, such as carbon black.
In that sense, it can be said that the alkyd resin does not significantly affect the coating performance itself.

The alkyd resin may be one modified with oil or fatty acid, or a so-called oil-free alkyd resin that is not modified with these. A type having an unsaturated bond copolymerizable with a vinyl monomer is suitable in the present invention.

The alkyd resin includes octyl acid, lauric acid,
Saturated fatty acids such as stearic acid or "persatic acid"; unsaturated fatty acids such as oleic acid, linoleic acid, lyluic acid, eleostearic acid or ricinoleic acid; "Vamoline 200.300J, Chinese tung oil (fatty acid), linseed oil (fatty acid), dehydrated castor oil (fatty acid), tall oil (fat #), cottonseed oil (fatty acid), soybean oil (fatty acid), olive oil (fatty acid), safflower oil (fatty acid)
, (semi-)drying oils (fatty acids) or hydrogenated coconut oil (fatty acids), such as castor oil (fatty acids) or rice bran oil (fatty acids);
Ethylene glycol, propylene glycol, with or without the use of one or a mixture of two or more oils or fatty acids, such as coconut oil (fatty acids) or non-drying oils (fatty acids) such as palm oil (fatty acids). glycerin,
Trimethylolethane, trimethylolpropane, neopentyl glycol, 1,6-hexanediol, 1.
2. One or more polyhydric alcohols such as 6-hexahydriol, pentaerythritol or sorbitol and benzoic acid, p-butylbenzoic acid,
Phthalic acid (anhydride), hexahydrophthalic acid (anhydride), tetrahydrophthalic acid (anhydride), phthalic acid, tetrachlorophthalic acid (anhydride), hexachlorophthalic acid (anhydride), tetrabromophthalic acid (anhydride), trimellitic acid, Himic acid, (anhydrous) succinic acid, (anhydrous) maleic acid,
(anhydrous) one or more carboxylic acids such as itaconic acid, fumaric acid, adipic acid, sepathic acid or oxalic acid in a conventional manner, and if necessary, "Cardura E" (a product of Shell Co., Ltd.), etc. Monoepoxy compounds such as glycidyl esters of fatty acids of "Epiclon 200.
400'', [polyepoxy compounds such as Epicote 828.100IJ, or diisocyanates such as tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate or 4,4'-methylenebis(cyclohexyl isocyanate);
One or more polyisocyanates obtained by addition reaction of each of these diisocyanates with the above-mentioned polyhydric alcohols or water, or polyisocyanates having an isocyanuric ring obtained by (co)polymerization of diisocyanates with each other. Suitable are those obtained by replacing a part of the polyhydric alcohols and carboxylic acids mentioned above and reacting them by a conventional method.

In this case, the alkyd resin must be of a saturated fatty acid or non-drying oil (fatty acid) modified type that does not have copolymerizable unsaturated bonds or has a small amount, or an oil-free alkyd resin that has not been modified with oil or fatty acids. For those products, it is necessary to introduce copolymerizable unsaturated bonds that serve as grafting points for other vinyl monomers into the alkyd resin using an unsaturated carboxylic acid such as (anhydrous) maleic acid or fumaric acid. Needless to say, it is.

The alkyd resin thus obtained is 0
It is used in a range of 10 to 10% by weight, but when used in a large amount exceeding 10% by weight, solvent resistance, stain resistance, etc. become inferior. Moreover, during polymerization, the carboxyl group in the alkyd resin and the epoxy group in the epoxy group-containing vinyl monomer react with each other, resulting in undesirable problems such as easy gelation.

Therefore, the amount of the alkyd resin to be used should be within the above-mentioned range, and the acid value, oil length, amount of copolymerizable unsaturated bonds, and the alkyd resin should be adjusted so that gelation does not occur due to the reaction between these groups. It is preferable to determine the molecular weight by considering the molecular weight of the polymer and the molecular weight of the modified copolymer obtained.

Typical aromatic vinyl monomers mentioned above include styrene, α-methylstyrene, pt-butylstyrene, and vinyltoluene, among which styrene is most preferred in terms of cost.

If the aromatic vinyl monomer is used in a large amount exceeding 60% by weight, the resulting coating film will have poor weather resistance and will be unsuitable as an outdoor paint resin. When used, it should be determined within 60% by weight depending on required performance such as gloss, texture and weather resistance. From the viewpoint of the balance of gloss, texture, leveling properties, and weather resistance, a range of 10 to 50% by weight is preferable.

Typical vinyl monomers that can be copolymerized with the epoxy group-containing vinyl monomers, aromatic vinyl monomers, and alkyd resins having copolymerizable unsaturated bonds include methyl (meth) Acrylate, ethyl (meth)acrylate, n-propyl (meth)
Acrylate, 1-propyl (meth)acrylate, n
-Butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate
Acrylate, cyclohexyl (meth)acrylate,
Various (meth)acrylates such as benzyl (meth)acrylate, dibromopropyl (meth)acrylate, tribromophenyl (meth)acrylate or alkoxyalkyl (meth)acrylate; unsaturated dicarboxylic acids such as maleic acid, fumaric acid or itaconic acid. Diesters of acids and monohydric alcohols; vinyl esters such as vinyl acetate, vinyl benzoate or "Beoba" (vinyl ester manufactured by Shell); "Viscoat BFSB"
FM, 3F or 3FMJ (fluorine-containing acrylic monomer manufactured by Osaka Organic Chemical ■), perfluorocyclohexyl (meth)acrylate, ciba-fluorocyclohexyl fumarate or N-1-propyl perfluorooctane sulfonamide ethyl (meth)acrylate (per)fluoroalkyl group-containing vinyl esters such as;
Fluorine-containing compounds such as vinyl ethers, (meth)acrylates, or unsaturated carboxylic acid esters; or olefins such as (meth)acrylonitrile, vinyl chloride, vinylidene chloride, vinyl fluoride, or vinylidene fluoride.

Typical vinyl monomers containing hydroxyl groups include 2-
Hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate Acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, di-2-hydroxyethyl fumarate, mono-
Collection of hydroxyalkyl esters of α,β-ethylenically unsaturated carboxylic acids such as 2-hydroxyethyl-monobutyl fumarate or polyethylene glycol mono(meth)acrylate (meth)acrylic acid, crotonic acid, maleic acid, fumaric acid, itacon α,β-ethylenically unsaturated carboxylic acids such as unsaturated monomers or dicarboxylic acids such as acid or citraconic acid, and molar esters of these dicarboxylic acids and monohydric alcohols;
Adducts with various polycarboxylic acids (anhydrides) such as the above α,β-unsaturated unsaturated carboxylic acid hydroalkyl esters, and “Cardura E”, coconut oil fatty acid glycidyl ester or octylic acid glycidyl ester Examples include monoglycidyl esters of monovalent carboxylic acids or adducts with monoepoxy compounds such as butylglycidyl ether, ethylene oxide or propylene oxide; or compounds containing methylol groups such as N-methylolated acrylamide, or hydroxyethyl vinyl ether. In the case of monomers containing functional groups such as such hydroxyl group-containing vinyl monomers, it is necessary to determine the amount used so as not to cause gelation, and the hydroxyl groups in the hydroxyl group-containing vinyl monomer and the above-mentioned The amount should be determined so that gelation does not occur due to reaction with the (β-methyl)glycidyl group in (β-methyl)glycidyl (meth)acrylate.

In obtaining the composition of the present invention, first, the epoxy group-containing vinyl copolymer is usually cleaved by solution polymerization, and then
The above-mentioned drying oil fatty acid is added to this copolymer, and in this copolymerization reaction, which can be called the first stage reaction, the polymer conversion rate of the epoxy group-containing vinyl copolymer is usually After securing 95% or more, drying oil fatty acid can be added to proceed with the addition reaction, which can be called the second stage reaction, without waiting for the completion of the copolymerization reaction.

Further, the reaction temperature is not particularly limited, and it may be at a temperature suitable for polymerizing each component compound as described above during the copolymerization reaction, that is, a temperature within the normally employed range of 50 to 140°C. On the other hand, during the addition reaction, a temperature suitable for the addition of each reaction component as described above, that is, 110~
The temperature may be in the range of 180° C., and particularly during the addition reaction, a high temperature may be used to promote this reaction.

Furthermore, in order to promote the addition reaction, a ring-opening catalyst for epoxy groups may be used. In that case, any known and commonly used catalyst can be used, but among them, triethylamine, diethylenetriamine, and imidazole are particularly representative. These include tertiary amines such as BF, complexes, or acids such as phosphoric acid or sulfuric acid.

In addition, as the polymerization initiator used for polymerization, any known and commonly used initiator can be used, but among them, particularly representative ones include azobisisobutyronitrile and benzoyl peroxide. , t-7' chill perbenzoate, t-butyl per octate, di-
Such as t-butyl peroxide. Furthermore, a chain transfer agent may be used in combination.

Known and commonly used solvents can be used, but the most representative ones include aromatic solvents such as toluene or xylene, ester solvents such as ethyl acetate, butyl acetate or cellosolve acetate, and alcoholic solvents such as methanol or butanol. or a ketone type solvent such as methyl ethyl ketone or methyl isobutyl ketone. Furthermore, aliphatic or alicyclic type solvents such as hexane, heptane, cyclohexane, methylcyclohexane, petroleum naphtha or mineral spirit can also be used.

The types, combinations, and amounts of such solvents are as follows:
The amount can be appropriately determined in consideration of the amount of the fatty acid used, the amount of the vinyl moiety used in the epoxy group-containing vinyl copolymer, and the like.

The fatty acid-modified vinyl copolymer obtained in this way is
Since it has both a double bond and a hydroxyl group in its molecule, it is possible to perform oxidative polymerization using a dryer and urethane crosslinking alone or in combination.

The dryer used here may be any dryer that is commonly used for paints, but the most typical dryers include cobalt, vanadium, manganese, cerium, lead, iron, calcium, and zinc. , naphthenate, octylate or resinate such as zirconium, nickel or tin.
It may be determined as appropriate depending on the combination of each component or required performance.

At this time, a small amount of an organic peroxide such as benzoyl peroxide, methyl ethyl ketone peroxide or t-butyl perbenzoate may be used in combination to enhance the effectiveness of the dryer. Furthermore, known and commonly used paint additives such as leveling agents can also be used in combination.

Typical polyisocyanates include aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate, or diphenylmethane diisocyanate; aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, or trimethylhexamethylene diisocyanate; or isophorone diisocyanate. , methylcyclohexane-2,4-(or 2,6-)diisocyanate, cycloaliphatic diisocyanates such as 4°4'-methylenebis(cyclohexylisocyanate) or 1,3-di(isocyanatomethyl)cyclohexane, etc.; Alternatively, each of these diisocyanates and the above-mentioned polyhydric alcohols, low molecular weight polyester resins (including oil-modified types) having functional groups that react with isocyanate groups, acrylic copolymers (styrene is used as a comonomer) ), adducts with water, etc., as well as biuret bodies and (co)polymers (including oligomers) of the above-mentioned diisocyanates.

By the way, when using the polyisocyanate for a period of time, aromatic diisocyanates and their derivatives, which yellow or crack when exposed to ultraviolet rays, are unsuitable for use as top coats, and are used exclusively for weather resistance reasons. Suitable for undercoat paints such as primers that do not require it. Therefore, in such cases, aliphatic diisocyanates, alicyclic diisocyanates, or various derivatives thereof, which have good weather resistance, may be used as the top coat.

The amount of polyisocyanate used is OH/NC
An equivalent ratio of O=1/'0.1 to 1/1.2 is suitable.

The composition of the present invention meets the various needs in this industry as described above. Crosslinking reaction by oxidative polymerization based on fatty acid residues contained in the modified copolymer or crosslinking reaction between the hydroxyl groups slightly present in the modified copolymer and the polyisocyanate blended therewith, and furthermore, The three types of crosslinking reactions between the two are:
It can be said that this is a unique composition in that one type of modified vinyl copolymer can be employed as desired, and a coating film with excellent performance can be obtained through such a crosslinking reaction.

Next, the present invention will be specifically explained with reference to Examples and Comparative Examples. In the following, all parts and percentages are based on weight unless otherwise specified.

(11 Examples and Comparative Examples Regarding Primer Example 1 800 parts of xylene was added to a four-way flask equipped with a thermometer, a reflux condenser, a stirrer, and a nitrogen gas inlet. ■
71 parts of long oil alkyd resin) and di-t-butyl peroxide (hereinafter abbreviated as DTBPO).
The temperature was raised to 125°C, and at the same temperature, 400 parts of styrene (St), 300 parts of methyl methacrylate (MMA), and 5 parts of acrylonitrile (AN) were charged.
5 parts of glycidyl methacrylate (GMA), 70 parts of ethyl acrylate (EA), 10 parts of azobisisobutyronitrile (AIBN), 10 parts of t-butyl peroctate (TBPO) and t-butyl. 5 parts of a mixture of 10 parts of perbenzoate (TBPB)
After the dropwise addition was completed, the temperature was kept at the same temperature for 5 hours until the nonvolatile content reached 53.9%. After 13 hours, the non-volatile content was 60.3% and the viscosity (Gardner; the same applies hereinafter) was 26. A solution of a fatty acid-modified acrylic copolymer having an acid value of 2.6 was obtained, and 400 parts of xylene was added to this solution to adjust the nonvolatile content to 50%.

< L, the resulting resin solution has a non-volatile content of 50.1%.
The viscosity is LM, the color number (Gardner; hereinafter the same) is 5 to 6, and the number average molecular weight (hereinafter the same) by gel nomeation chromatography (GPC) is 40.
It was a clear solution.

Example 2 In a flask similar to Example 1, "Pesocozole 1343" was added.
200 parts of J (medium oil alkyd resin made by the same company), 1300 parts of xylene, and 3 parts of DTBPO were charged and heated to 120°C.
At the same temperature, 300 parts of St, 300 parts of MMA,
A mixture consisting of 200 parts of GMA, 100 parts of n-butyl acrylate (BA), 15 parts of AIBN, 10 parts of TBPO, and 2 parts of TBPB was added dropwise over 5 hours, and was further maintained at the same temperature for 12 hours to polymerize. By continuing the process, an acrylic copolymer having a nonvolatile content of 42.0% and a viscosity of Y was obtained.

Next, 100 parts of cottonseed oil fatty acid and 300 parts of dehydrated castor oil fatty acid were added to this copolymer and reacted at 150°C until the acid value became approximately 1, resulting in a non-volatile content of 50.8%.
, the viscosity is Z-Zi, the acid value is 1.1, the number of colors is 1-2,
A transparent resin solution having a number average molecular weight of 7,200 was obtained.

Example 3 In a flask similar to Example 1, 1300 parts of xylene,
Charge 3 parts of DTBPO and raise the temperature to 120°C, and at the same temperature add 400 parts of St, 200 parts of MMA, 200 parts of BA, 200 parts of GMA, 15 parts of ATBN, and T B'P.
A mixture consisting of 5 parts of
An acrylic copolymer of 2.5% and a viscosity of X was obtained. Next, 200 parts of soybean oil fatty acid and 100 parts of coconut oil fatty acid were added to this copolymer and reacted at 150°C until the acid value became approximately 1, resulting in a non-volatile content of 50.4% and a viscosity of Y. −
Z has an acid value of 1.2, a color number of 3, and a number average molecular weight of 6000.
A clear resin solution was obtained.

To the thus obtained resin solution, 0.2% (solid content ratio) of 6% cobalt naphthenate and 0.4% of 24% lead naphthenate were added.
(solid content ratio) added. Furthermore, a paint obtained by adding an equivalent amount of Parnock DN-950 (hexamethylene diisocyanate curing agent manufactured by Daikomoto Ink Kagaku Kogyo Co., Ltd.) to the paint after addition of the dryer in Example 1 was also prepared.

As a comparative example, a commercially available acetic acid-vinyl acrylic primer was used.

As for the permeability test item, 1 g of a solution diluted with xylene to a non-volatile content of 30% was dropped onto a commercially available slate plate, and the permeation depth was examined. Water resistance and alkali resistance were evaluated by spray painting on a slate board, drying for one week, immersing in tap water and saturated calcium hydroxide aqueous solution for two days, and evaluating the coated surface. Solvent resistance was evaluated by spray painting on a slate board and spotting toluene after 10 minutes to evaluate the painted surface.

The results are shown in Table 1.

(2) Examples and Comparative Examples Regarding Top Coat Example 4 In a four-eye flask equipped with a thermometer, reflux condenser, stirrer, and nitrogen gas inlet, 800 parts of xylene, 71 parts of Hesokosol P-470-70J, 1 part and 2 parts of DTBPO were charged, the temperature was raised to 125°C, and at the same temperature, 400 parts of St, 300 parts of BA, 55 parts of AN, and GM were added.
125 copies of A, 70 copies of MMA, 10 copies of ATBN, T
A mixture consisting of 7 parts of BPO and 4 parts of TBPB was added dropwise over 5 hours, and the temperature was kept at the same temperature for 5 hours after the addition, and when the non-volatile content reached 53.9%, soybean oil fatty acid Adding 200 parts of 2MIZ and 0.2 parts of 2MIZ and carrying out an addition reaction between glycidyl groups and carboxyl groups at the same temperature resulted in a non-volatile content of 60.3% and a viscosity of 7.
In Example 3, a solution of a fatty acid-modified acrylic copolymer having an acid value of 2.6 was obtained, and 400 parts of xylene was added to this solution to adjust the nonvolatile content to 50%.

The resin solution thus obtained had a nonvolatile content of 50.1%,
Example 5 A transparent solution with a viscosity of V and a color number of 5 to 6 was prepared. In a flask similar to Example 1, [Hesokozol 1343] was added.
200 parts of J, 1300 parts of xylene, 3 parts of DTBPO
At the same temperature, add 300 parts of St, 100 parts of St, 200 parts of GMA, 300 parts of EA, 15 parts of 8 IBN, 10 parts of TBPO and TBPB.
A mixture consisting of 2 parts of
．． An acrylic copolymer with a viscosity U of 'c% was obtained.

When reacted at ℃ until the acid value was about 1, the nonvolatile content was 50.8%, the viscosity was x-y, the acid value was 1.1, and the number of colors was 1.
A clear solution of ~2 was obtained.

Next, 120 parts of the varnish obtained in Example 4.5, 40 parts of "Tie Bake CR-90J (titanium oxide manufactured by Ishiya Sangyo ■)"
The mixture was milled in a sand mill to obtain an own paint with a PWC of 40%. To these were added 1 part of 6% cobalt naphthenate, 2 parts of 24% lead naphthenate, and 1 part of anti-skinning agent. An additional 10 parts of Burnock DN-950 was added to half of the paint.

For comparison, a commercially available vinyl acetate-acrylic exterior paint and a commercially available acrylic urethane exterior paint were used.

These paints were diluted with urethane thinner and sprayed on commercially available slate plates and polished mild steel plates, and after drying at room temperature for one week, a grain quality test was conducted. Furthermore, weather resistance was judged based on the gloss retention rate after 1 year of dew in the Sakai area. Table 2 shows the results.
Shown below.

Claims (1)

[Claims] 0 to 60% by weight of aromatic vinyl monomers, 5 to 25% by weight of vinyl monomers containing epoxy groups, 0 to 10% by weight of alkyds having copolymerizable unsaturated bonds, and other vinyl monomers copolymerizable with these. Copolymerize 5 to 95% by weight of heptamine, and then add 5 to 60 parts by weight of fatty acid to 100 parts by weight of the epoxy group-containing acrylic copolymer thus obtained.
A coating composition for building materials containing a modified acrylic copolymer obtained by addition reaction in parts by weight.