JPH06192531A - Thermosetting acrylic resin composition having excellent adhesivity - Google Patents

Abstract

(57) [Summary] [Structure] Part of an acrylic resin obtained by copolymerizing a monomer having an α, β-monoethylenically unsaturated group is composed of a chlorinated acrylic resin and a curing agent. A thermosetting acrylic resin composition having excellent adhesion. [Effect] A thermoplastic acrylic resin composition having excellent adhesiveness is provided and is useful as a paint or an ink binder.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention has excellent adhesiveness,
The present invention relates to a thermosetting acrylic resin composition which is useful as an adhesive, a surface coating agent, and an ink binder and has excellent adhesion.

[0002]

2. Description of the Related Art Conventionally, thermosetting acrylic resins are used for paints,
It is used as a sealer or top coat for adhesives, paper, metals, plastics, wood, rubber, and inorganic materials. The thermosetting acrylic resin composition currently used cannot always be said to have sufficient adhesion to plastics. Among the plastics, it is particularly difficult to adhere to sheet molding compounds (SMC) and polyethylene terephthalate, and in the past, adhesion was a problem due to stickiness, stains, temperature dependence, etc. It was

[0003]

DISCLOSURE OF THE INVENTION The inventors of the present invention have made extensive studies to solve the above problems, and as a result, in an acrylic resin, a thermosetting acrylic resin composition in which a part of the acrylic resin is chlorinated. However, they found that the adhesiveness to plastics was excellent, and arrived at the present invention.

[0004]

[Means for Solving the Problems]

[Means for Solving the Problem] That is, the present invention is as follows. (A) Excellent adhesion, characterized in that a part of the acrylic resin obtained by copolymerizing a monomer having an α, β-monoethylenically unsaturated group is composed of a chlorinated acrylic resin and a curing agent. A thermosetting acrylic resin composition. (B) The monomer having an α, β-monoethylenically unsaturated group contains 0.5% by weight or more of a chlorinated monomer having an α, β-monoethylenically unsaturated group ( (A) A thermosetting acrylic resin composition having excellent adhesion as described above. (C) Heat generated by reacting a monomer having an α, β-monoethylenically unsaturated group with an acrylic resin made of a monomer having a hydroxyl group having an α, β-monoethylenically unsaturated group and a chlorine compound The thermosetting acrylic resin composition having excellent adhesion as described in (a) above, wherein the chlorine compound content in the curable acrylic resin composition is 0.5% by weight or more. (D) The thermosetting acrylic resin composition has a hydroxyl value of 10 to 10
The thermosetting acrylic resin composition having excellent adhesiveness according to claim 3, which has 150 KOHmg / g. (E) The curing agent is an amino resin, and the content in the composition is 5 to 5.
40% by weight of the thermosetting acrylic resin composition having excellent adhesion as described in (A) above.

In the present invention, a method for producing a partially chlorinated acrylic resin is as follows.
Is mentioned. 1) A method of obtaining a partially chlorinated acrylic resin by copolymerizing a chlorinated monomer with a hydroxyl group-containing monomer and an α, β-monoethylenically unsaturated group-containing monomer. 2) A method of synthesizing an acrylic resin having a hydroxyl group and reacting the hydroxyl group with a chlorine compound to obtain an acrylic resin partially chlorinated. As the chlorinated monomer in the above production method 1),
It is represented by the following general formula (1). (In the formula, R is a chain or cyclic alkyl group having 1 to 22 carbon atoms), acrylic acid chloride, or methacrylic acid chloride, and one or more of them can be used.

Examples of the monomer having a hydroxyl group include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, and an adduct of polycaprolactone and hydroxyethyl (meth) acrylate (Placcel F series). ;
Product name: Daicel Chemical Industries, Ltd.), Addition product of polyethylene glycol and methacrylic acid (Blenmer PE series; Product name: NOF Corporation), Addition product of polypropylene glycol and methacrylic acid (Bremmer PP series; Product) Means Nippon Oil & Fat Co., Ltd. etc. are mentioned, and these can be used 1 or more types. Examples of the monomer having an α, β-monoethylenically unsaturated group include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate,
Isobutyl (meth) acrylate, tert-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, tridecyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) Acrylate, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid and their monoesters, dimethylaminoethyl (meth)
Examples thereof include acrylate, diethylaminoethyl (meth) acrylate, glycidyl (meth) acrylate, methylglycidyl (meth) acrylate, and allylglycidyl ether, and one or more of them can be used.

Other monomers include, for example, styrene, α-methylstyrene, vinyltoluene, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl propionate, acrylamide, methacrylamide, methylolacrylamide, methylolmethacrylamide, ethylene, propylene. , C _{4 to} C ₂₀ α-olefins and the like, and one or more of them can be used. It is suitable to limit the amount of the chlorinated monomer used so that it is 0.5% by weight or more in the acrylic resin.
A more preferable content is 5% by weight or more. When the content of the chlorinated monomer in the acrylic resin is less than 0.5% by weight, the adhesion to plastics is poor. The amount of the monomer having a hydroxyl group is appropriately limited so that the hydroxyl value of the acrylic resin is 10 to 150 KOHmg / g. Hydroxyl value is 10 KOHmg / g
If it is less than the above, the reaction with the curing agent is insufficient and the solvent resistance is poor. If the hydroxyl value exceeds 150 KOHmg / g, the water resistance of the coating film will decrease. The acrylic resin can be synthesized by a conventional method, and can be produced by any known polymerization method such as a solution polymerization method, a suspension polymerization method, a bulk polymerization method and an emulsion polymerization method.

In that case, as the polymerization initiator, for example, azobisisobutyronitrile, 4,4'-azobis (4-cyanopentanoic acid), benzoyl peroxide, t-butylperoxy-2-ethylhexanoate. , Cumene hydroperoxide, potassium persulfate, hydrogen peroxide, 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) propioamide] and the like can be used, and if necessary, chain transfer As the agent, dodecyl mercaptan, mercaptoethanol, α-methylstyrene dimer and the like can be used. As the monomer having a hydroxyl group and the monomer having an α, β-monoethylenically unsaturated group in the production method 2), one or more of those exemplified in the production method 1) can be used. The above acrylic resin can be synthesized by a conventional method as in the production method 1). In the production method 2), the chlorine compound is not particularly limited as long as it is a compound capable of reacting with a hydroxyl group, but a chlorine compound having an acid anhydride group is preferable in production. Examples thereof include chlorendic anhydride, tetrachlorophthalic anhydride, tetrachlorosuccinic anhydride, dichloromaleic anhydride and the like, and one or more of them can be used. . It is appropriate to limit the amount of the chlorine compound used so that the amount of the chlorine compound in the resin is 0.5% by weight or more. A more preferable content is 5% by weight or more. If the content of the chlorine compound in the resin is less than 0.5% by weight, the adhesion to plastics is poor. The amount of the monomer having a hydroxyl group is appropriately limited so that the hydroxyl value of the acrylic resin is 10 to 150 KOHmg / g. Hydroxyl value is 10K
If it is less than OHmg / g, the reaction with the curing agent is insufficient and the solvent resistance is poor. If the hydroxyl value exceeds 150 KOHmg / g, the water resistance of the coating film will decrease.

The curing agent used in the thermosetting acrylic resin composition of the present invention includes amino resins. The amino resin is a resin synthesized from at least one of melamine, urea, benzoguanamine, glycoluril and the like and formaldehyde, for example, a methylol group of a lower alcohol such as methanol, ethanol, propanol, isopropanol, butanol or isobutanol. Part or all of which is alkyl etherified is used. The content of the amino resin in the composition is 5 to
50% by weight is suitable. If the content is less than 5% by weight, the curing reaction with the acrylic resin is insufficient and the solvent resistance of the coating film is poor, and if it exceeds 50% by weight, the appearance of the coating film is poor. Also, para-toluene sulfonic acid as a curing catalyst,
An external catalyst typified by dodecylbenzene sulfonic acid, naphthalene sulfonic acid or amine neutralized products thereof can be added. When the thermosetting acrylic resin composition of the present invention is used in a solvent-based paint, the solvent that can be used is not particularly limited, and examples thereof include aliphatic hydrocarbons such as hexane and heptane, aromatic hydrocarbons such as toluene and xylene. Esters such as hydrogen, ethyl acetate, butyl acetate,
Examples thereof include ketones such as acetone and methyl isobutyl ketone, and alcohols such as butyl alcohol. When the thermosetting acrylic resin composition of the present invention is used as a sealer and a base coat paint, a metal pigment, a coloring pigment and the like may be added in a predetermined amount. In the thermosetting acrylic resin composition of the present invention, various resins such as acrylic resin, epoxy resin, polyester resin, synthetic resin such as polyamide, or fibrin derivative are blended to such an extent that the object of the present invention is not impaired. In addition, flow additives, antiblocking agents, ultraviolet absorbers, benzoin, antistatic agents, antioxidants and other commonly used coating additives may be added. Further, when used as a clear coat, a small amount of pigment may be added so that the pigment is colored to such an extent that the hiding property is not fully expressed. When the thermosetting acrylic resin composition of the present invention is used as a coating composition, the above components are blended by a general method, and a Ford cup No. 1 is used with a diluting solvent. 4 is prepared so that the viscosity at 25 ° C. is within the range of 10 to 50 seconds to prepare a paint, and the paint is directly applied to various plastics. Next, a coating film is formed by heating at room temperature or by heating. As a coating method, a usual method, for example, brush coating, spray coating, dip coating and the like can be mentioned.

[0010]

EXAMPLES The present invention will be described below with reference to Examples and Comparative Examples for more specific description, but the present invention is not limited to these Examples. In the description, "part" and "%" are by weight unless otherwise specified. Reference Example 1 Production Method 1) Acrylonitrile partially chlorinated by copolymerization of a chlorinated monomer with a hydroxyl group-containing monomer and an α, β-monoethylenically unsaturated group-containing monomer. How to get a resin. (Production of acrylic resin a-1 to 6) Stirrer, thermometer,
90 parts of toluene and 10 parts of n-butanol were charged into a four-necked flask equipped with a reflux condenser and a nitrogen introducing tube,
The temperature was raised to 100 degrees. The monomers shown in Table 1 and 2 parts of N, N′-azobisisobutyronitrile as a polymerization initiator were added dropwise thereto over 5 hours, and thereafter, the mixture was kept at 100 ° C. for 5 hours to obtain an acrylic resin ( a-1) to (a-6) were obtained. Reference Example 2 Production method 2) A method of synthesizing an acrylic resin having a hydroxyl group and reacting the hydroxyl group with a chlorine compound to obtain an acrylic resin partially chlorinated. (Production of acrylic resins b-1 to b-6) Reference Example 1 except that the solvent was changed to 90 parts of toluene and 10 parts of butyl acetate.
Acrylic resin having a hydroxyl group consisting of the monomers shown in Table-2 was synthesized by the same method as described above, and the chlorine compound shown in Table-2 was put into a flask and reacted at 100 ° C for 2 hours to obtain acrylic resin (b-1). (B-6) were obtained. Reference Example 4 (Preparation of clear coat paint) Acrylic resin 140 parts obtained in Reference Examples 1 and 2 and Uban 225 (butylated melamine resin, manufactured by Mitsui Toatsu Chemicals, Inc., solid content 60%) 50 parts,
2 parts of para-toluene sulfonic acid was mixed with stirring to obtain toluene 5
Ford No. with a mixed solvent consisting of 0 part and 50 parts of butyl acetate. It was diluted to 30 seconds / 25 ° C. in 4 to obtain a clear coat paint.

Example 1 A clear coat paint was prepared from the acrylic resin (a-1) by the method shown in Reference Example 4. Various plastics were coated with air spray to a dry film thickness of 30 μm, set for 10 minutes, and then heated at 120 ° C. for 20 minutes to obtain a test plate. Table 3 shows the test evaluation of the coating film. Examples 2 to 6 and Comparative Examples 1 to 6 Paints were prepared in the same manner as in Example 1 and test plates were obtained by the same method. Table 3 shows the test evaluation of the coating film. Example 7 A coating material was prepared in the same manner as in Example 1 except that 50 parts of acrylic resin (a-1) and 50 parts of (b-4) were mixed and used, and a test plate was obtained by the same method. Table 3 shows the test evaluation of the coating film.
Shown in.

[0012]

[Table 1]

[0013]

[Table 2]

[0014]

[Table 3]

[0015]

[Table 4]

Test Method and Evaluation Method 1) Adhesion Test After the cellophane tape was attached to the dry coating film, the cellophane tape was peeled off. The case where there was no peeling of the coating film was evaluated as ⊚, the case where the film was slightly peeled was evaluated as ○, and the case where the film was significantly peeled was evaluated as ×. 2) Solvent resistance The surface of the coating film was rubbed 50 times with gauze impregnated with xylene and then observed. Those with no trace were evaluated as ◎, and those with a trace were evaluated as x. 3) Water resistance After immersing the coating film in warm water of 50 ° C. for 48 hours, the coating film was observed. Those with no abnormality were evaluated with ⊚, and those with whitening and blister were evaluated with ×.

[0017]

EFFECTS OF THE INVENTION It is clear from Table 3 that the thermosetting acrylic resin composition of the present invention having excellent adhesion is excellent in adhesion, solvent resistance and water resistance to various plastic materials. .

Claims (5)

[Claims] 1. Adhesion, characterized in that an acrylic resin obtained by copolymerizing a monomer having an α, β-monoethylenically unsaturated group is composed of a chlorinated acrylic resin and a curing agent. Excellent thermosetting acrylic resin composition. 2. The α, β-monoethylenically unsaturated group-containing monomer contains 0.5% by weight or more of a chlorinated monomer having an α, β-monoethylenically unsaturated group. A thermosetting acrylic resin composition having excellent adhesion according to claim 1. 3. A monomer having an α, β-monoethylenically unsaturated group is reacted with an acrylic resin made of a monomer having an α, β-monoethylenically unsaturated group having a hydroxyl group and a chlorine compound. The thermosetting acrylic resin composition having excellent adhesion according to claim 1, wherein the content of chlorine compound in the thermosetting acrylic resin composition is 0.5% by weight or more. 4. The thermosetting acrylic resin composition according to claim 3, wherein the thermosetting acrylic resin composition has a hydroxyl value of 10 to 150 KOHmg / g. 5. The thermosetting acrylic resin composition having excellent adhesiveness according to claim 1, wherein the curing agent is an amino resin and the content of the composition is 5 to 40% by weight.