JPS6284165A - Acrylic lacquer composition - Google Patents

Abstract

PURPOSE:To provide the titled composition composed of a (co)polymer of a vinyl monomer containing a cycloalkyl (meth)acrylate at a specific ratio and an organic solvent, having excellent gloss, building property and sharpness of coating film and good solvent dilution property and sprayability. CONSTITUTION:The objective composition can be produced by (co)polymerizing a vinyl monomer containing a cycloalkyl acrylate and/or cycloalkyl methacrylate (e.g. cyclohexyl methacrylate) at a ratio of >=10wt% (preferably >=30wt%) in the vinyl monomer (the other monomer component is e.g. butyl methacrylate) in an organic solvent (e.g. toluene) in the presence of a polymerization initiator (e.g. benzoyl peroxide). The amount of the organic solvent in the composition is preferably <=45wt% to obtain a coating film having excellent building property.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to new and improved acrylic lacquer compositions. More specifically, it provides a coating film with excellent gloss, durability, sharpness, weather resistance, and solvent resistance that is useful for various uses such as paints and inks, as well as solvent dilutability, spray workability, and drying properties. The present invention relates to an acrylic lacquer composition that has excellent properties such as:

(Prior art) Acrylic lacquer has been widely known as an acrylic resin paint, and has superior weather resistance, chemical resistance, water resistance, etc. than acrylic resin paints and other resin-based paints, resulting in a high-quality finish. It is widely used in fields that require

Acrylic lacquer is used to achieve the desired coating film t# [performance] without three-dimensional crosslinking and curing with amine resins such as melamine resins, isocyanate compounds such as tolylene diisocyanate, epoxy resins, etc. In general, acrylic resins for lacquers have higher molecular weights and higher glass transition points (TO) than cross-linked acrylic resins, and in order to further improve drying properties, nitrocellulose or cellulose acetate is added to the acrylic lacquers. Many cellulose derivatives such as butyrate are added.

(Problems to be solved by the invention) Therefore, conventional acrylic lacquers have poor solvent dilutability and atomization during spraying, and the resulting coating film has poor leveling during painting, lacks luster, and lacks thickness. There are problems such as poor image quality, poor image clarity, and poor weather resistance.

In other words, if the molecule ω of the acrylic resin is increased or a cellulose derivative is used, the solvent dilutability deteriorates, and as a result, a large amount of solvent is required to match the viscosity of the spray etc. The non-volatile content of the paint is low,
To obtain a desired coating thickness, the amount of q cloth must be increased and the coating thickness when wet must be increased. Therefore, vertical surfaces etc. tend to sag, and the dried paint film becomes thinner.

Furthermore, those with a large molecular weight have poor atomization during spraying, resulting in severe roughness of the coating film, difficulty in obtaining a smooth coating surface, and extremely poor gloss and appearance. In addition, it has been pointed out that the shortcomings of conventional acrylic lacquers in general include poor durability and image clarity.

As a method to improve these drawbacks, strong solvents or strong solvents with high boiling points are used to improve solvent dilution and spray workability, but this increases cost and increases the boiling point. Drying performance deteriorates and is not fully satisfied.

In addition, if, for example, styrene monomer is introduced into a part of the acrylic resin for lacquer in order to improve gloss and durability, the gloss and durability will improve, but yellowing will be strong when exposed outdoors and weather resistance will be reduced. Deteriorate.

Furthermore, it has been pointed out that one of the major drawbacks of conventional acrylic lacquers is that they tend to chalk easily when exposed outdoors or in areas exposed to strong ultraviolet rays, resulting in a large decrease in gloss.

Although acrylic lacquer is often used as a relatively expensive, high-quality, high-grade finishing paint, it has many problems as described above, and there has been a strong demand for improvements.

As a result of intensive research to overcome the above-mentioned problems, the inventors of the present invention have created a coating film with excellent gloss, durability, sharpness, solvent resistance, and weather resistance, as well as solvent dilubility and weather resistance. An acrylic lacquer composition with excellent sprayability and drying properties has been completed without degrading other properties.

That is, an acrylic lacquer composition comprising a (co)polymer obtained by (co)polymerizing a vinyl spinning wheel matrix containing a specific amount of acrylic acid cycloalkyl ester and/or methacrylic acid cycloalkyl ester, )
Even when the polymer has a relatively high molecular weight, its solution viscosity is low, and various acrylic resin paints such as enamel using this acrylic lacquer composition have excellent solvent dilutability and spray workability, and the resulting coating film is It was discovered that it dries quickly, has good leveling properties, and has excellent properties such as gloss, long-lasting properties, and weather resistance.

(Means and effects for solving the problems) The present invention provides acrylic acid cycloalkyl ester and/or methacrylic acid cycloalkyl ester in a vinyl 1lffi body.
The present invention relates to an acrylic lacquer composition consisting of a (co)polymer (Δ) obtained by (co)polymerizing a vinyl monopendicular body containing at least % by weight and an organic solvent.

Acrylic acid cycloalkyl ester and/or methacrylic acid cycloalkyl ester (hereinafter referred to as (meth)acrylic acid cycloalkyl ester) used in the present invention.

) include cyclohexyl acrylate, cyclohexyl methacrylate, methylcyclohexyl acrylate, methylcyclohexyl methacrylate, tert-butylcyclohexyl methacrylate, cyclooctyl acrylate, cyclooctyl methacrylate, cyclododecyl acrylate, cyclododecyl methacrylate, etc. .

m of the (meth)acrylic acid cycloalkyl ester which is an essential component in the (co)polymer (A) in the present invention is (
The amount is 10% by weight or more, more preferably 30% by weight or more in the vinyl single ω substance used to obtain the co)polymer (A). (meth)acrylic acid cycloalkyl ester is 1
If it is less than 0% by weight, the characteristics of the acrylic lacquer composition of the present invention, such as a good balance between drying properties and leveling properties, as well as gloss, long-lasting properties, solvent resistance, and weather resistance, will not be fully exhibited, and it will not be possible to achieve the intended purpose. The desired coating performance cannot be obtained.

The vinyl monomers used to obtain the (co)polymer (A) include, in addition to (meth)acrylic acid cycloalkyl ester as an essential component, copolymerization components such as methyl (meth)acrylate, ethyl ( meth)acrylate, propyl(meth)acrylate, isopropyl(meth)acrylate, butyl(meth)acrylate, isobutyl(meth)acrylate, tertiary-butyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, lauryl(meth)acrylate, (Meth)acrylic acid alkyl esters such as stearyl (meth)acrylate; (meth)acrylamide, (meth)acrylonitrile, N,N'-dimethylaminoethyl (meth)acrylate, styrene, α-methylstyrene, vinyltoluene, vinyl acetate , vinylpyridine, vinylimidazole, etc. These (meth)acrylic acid alkyl esters and other vinyl monomers are used as the remainder of the (meth)acrylic acid cycloalkyl ester, and can be used as necessary to achieve the desired coating performance in a well-balanced manner. Bye.

The (co)polymer (A) can be prepared by known combination methods. However, considering the form of use as a lacquer, it is preferable to use a solution polymerization method since the operation of dissolving the (co)polymer (Δ) in an organic solvent is not necessary.

When employing the solution polymerization method, radical polymerization initiators such as azobisisobutyronitrile, benzoyl peroxide, and di-tert-butyl peroxide can be used as the polymerization initiator, and as the polymerization solvent, Toluene, xylene and other high-temperature aromatic solvents; Ester solvents such as ethyl acetate, butyl acetate and cellosolve acetate; Ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone; Alcohols such as methyl alcohol, ethyl alcohol and butyl alcohol. These solvents can be used alone or in combination.

The organic solvent used in the present invention is not particularly limited as long as the polymerization solvent used in solution polymerization as described above can be used as is, and it can dissolve the (co)polymer (A) at a relatively high concentration. Further, it is preferable that the amount of the organic solvent in the acrylic lacquer composition of the present invention is 45% by weight or less, since a coating film with particularly excellent durability can be obtained.

(Effects of the Invention) The acrylic lacquer composition of the present invention provides a coating film with excellent gloss, durability, sharpness, weather resistance, and solvent resistance, and also has excellent solvent dilutability, spray workability, It has excellent drying properties and can be used not only as a clear paint, but also as a colored enamel paint by dispersing various inorganic and organic pigments using known pigment dispersion methods. Further, various known additives for paints can be added as necessary.

The paint thus prepared can be applied to wood products, metals, plastics, etc. using general coating methods such as spray coating, roll coating, and heka-coating.

Example 1 25 parts of toluene and 25 parts of butyl acetate were placed in a four-bottle flask equipped with a stirrer, thermometer, condenser, and nitrogen gas inlet tube, and the temperature was raised to 90°C under a nitrogen gas stream.
A mixture consisting of 15 parts of hexyl methacrylate, 5 parts of styrene, 15 parts of butyl methacrylate, 15 parts of methyl methacrylate and 0.5 parts of benzoyl peroxide was added dropwise over 2 hours, and further maintained at the same temperature for 4 hours.
Copolymer solution with non-volatile content of 50.2% and viscosity of 71 to Z2 (
Hereinafter, it will be referred to as acrylic lacquer composition (1). ) was obtained.

Example 2 35 parts of toluene and 15 parts of isopropyl alcohol were charged into the same reaction vessel as used in Example 1, and the temperature was raised to 80°C under a nitrogen gas stream, and 25 parts of cyclohexyl acrylate and 20 parts of methyl methacrylate were added thereto. , 5 parts of butyl acrylate and 0.3 parts of azobisisobutyronitrile
A mixture consisting of 50% and 50% was added dropwise over 2 hours, and kept at the same temperature for 4 hours to obtain a mixture with a non-volatile content of 49.8% and a viscosity of 72~z3.
copolymer solution (hereinafter referred to as acrylic lacquer composition (2)
). ) was obtained.

Comparative Example 1 38.5 toluene was added to the same reaction vessel used in Example 1.
1 part and 16.5 parts of isopropyl alcohol,
A mixture consisting of 35 parts of methyl methacrylate, 7 parts of butyl acrylate, 3 parts of butyl methacrylate, and 0.4 parts of benzoyl peroxide was added dropwise to the mixture heated to 90°C under a nitrogen gas stream over 2 hours, and the mixture was further heated at the same temperature. 4
A comparative copolymer solution (hereinafter referred to as comparative lacquer composition (1)) having a nonvolatile content of 45.6% and a viscosity of 73 to z4 was obtained by holding for a certain period of time.

Comparative Example 2 30 parts of toluene and 25 parts of butyl acetate were charged into the same reaction vessel as used in Example 1, and the mixture was heated at 80°C under a nitrogen gas stream.
3 parts of cyclohexyl acrylate, 25 parts of methyl methacrylate, 10 parts of styrene, 7 parts of butyl acrylate, and 0.
A mixture consisting of 3 parts was added dropwise over 2 hours and kept at the same temperature for 4 hours to give a non-volatile content of 45.2% and a viscosity of 72 to Z.
Comparative copolymer solution of No. 3 (hereinafter referred to as comparative lacquer composition (No. 2)
). ) was obtained.

Example 3 Acrylic lacquer composition obtained in Examples 1-2 (1
) to (2) and comparative lacquer compositions (1) to (2) obtained in Comparative Examples 1 to 2, titanium oxide (Tiebake R-820,6 manufactured by Hara Sangyo (1 part)) was added to each of the comparative lacquer compositions (1) to (2) at a pigment weight concentration. 40% and dispersed in a sand mill to prepare white enamels. Each of the obtained white enamels was applied to a mild steel plate with air spray to a dry film thickness of 20μ, and dried at room temperature for 48 hours. After that, the performance of the coating film was evaluated.

The performance of the coating film is determined by the following performance test method: ◎〜○〜Δ〜
The evaluation was performed on a four-level scale of ×, and the evaluation results are shown in Table 1.

<Performance test method> Comparison of two 60 degree specular reflectance measurements.

Durability: Visual judgment of paint film.

Judgment by spot test of solvent-resistant Niratsuka thinner.

Spray - Workability Judged based on the workability of the temporary varnish spray.

Judging by how easy it is to dilute with solvent-dilutable Niratsuka thinner.

Drying: Judgment by finger pressure immediately after drying and masking test.

Weather resistance: Judgment based on gloss retention after outdoor exposure.

Supplementary manuscript (spontaneous) October 25, 1985

Claims (1)

[Claims] 1. Acrylic acid cycloalkyl ester and/or methacrylic acid cycloalkyl ester in vinyl monomer
An acrylic lacquer composition comprising a (co)polymer (A) obtained by (co)polymerizing vinyl monomers contained in a proportion of at least % by weight and an organic solvent.