JPS6213469A - Coating agent - Google Patents

Abstract

PURPOSE:To obtain a coating agent which can be thickcoated and allows curing time to be shortened, by blending a salt of a copolymer of isobutylene, maleic acid and styrene or an acrylic acid compd. with water. CONSTITUTION:A coating agent contains a salt of a copolymer of isobutylene, maleic acid or anhydride and styrene and/or a salt of a copolymer of isobutylene, maleic acid or anhydride and an acrylic acid compd. and water. Pref. the terpolymer is composed of 0.5-10mol of maleic acid or anhydride and 0.01-1.5mol of styrene or acrylic acid compd. per mol of isobutylene. Preferred examples of the salts are sodium, potassium and ammonium salts.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a coating agent, and more particularly, to a coating agent that contains water and whose water content can evaporate in a short period of time after coating.

[Prior Art] As a coating agent applied to various materials such as metals and wood for the purpose of rust prevention and waterproofing, a coating agent consisting of a salt of an inbutylene-maleic anhydride copolymer and water is conventionally known. After such a coating agent is applied to a surface to be coated, moisture is evaporated, and then the coating agent is generally cured under predetermined conditions.

[Problems to be Solved by the Invention] Although such conventional coating agents have relatively excellent functions in terms of rust prevention or waterproofing, it takes a long time for water to evaporate after application.

There are problems in that thick coating, that is, the thickness of the coating layer cannot be increased, and that overall curing including water evaporation takes a long time.

It is an object of the present invention to solve these conventional problems and to provide a coating agent whose water content evaporates in a short period of time after application, allowing for thick application and shortening the overall curing time.

[Means for Solving the Problems] In order to achieve the above object, the present inventors have conducted intensive research focusing on the copolymer components of the copolymer, and as a result, the above-mentioned conventional binary copolymer Instead of polymers.

The present invention was completed by discovering that excellent effects can be obtained when a specific terpolymer is used as a coating agent component.

That is, the coating agent of the present invention is made of isobutylene-
It is characterized by containing a salt of maleic acid or its anhydride-styrene copolymer and/or a salt of isobutylene-maleic acid or its anhydride-acrylic acid compound copolymer; and water.

[Specific Description] As mentioned above, the coating agent of the present invention is a salt of isobutylene-maleic acid or its anhydride-styrene copolymer, or a copolymer of isobutylene-maleic acid or its anhydride-acrylic acid compound. or a mixture of salts of these two types of ternary copolymers.

In such a ternary copolymer, the composition ratio of each copolymer component is not particularly limited;
Maleic acid or its anhydride is 0.5 per mole
~lO mol, 0 styrene or acrylic acid compounds
．． It is preferable to set the amount to be about 0.01 to 1.5 moles. In addition, acrylic acid compounds include, but are not particularly limited to, methyl acrylate,
Ethyl acrylate, propyl acrylate, butyl acrylate.

Octyl acrylate and the like are preferred. The coating agent of the present invention contains a salt of such a terpolymer as a constituent component, and examples of such salt include, for example,
Sodium salts, potassium salts or ammonium salts are preferred.

The salt of this ternary copolymer is produced, for example, as follows. That is, first, predetermined amounts of each copolymer component except inbutylene are charged into a reaction vessel, cooled and sufficiently degassed. Next, a predetermined amount of inbutylene is added and a copolymerization reaction is carried out with stirring. At this time, the reaction temperature is 30 to 200°C, preferably 45 to 150°C,
The reaction time is 0.5 to 20 hours, preferably 1 to 10 hours.
Set to time. In this copolymerization reaction, acetonitrile, nitromethane, nitroethane,
Solvents such as methyl ethyl ketone, acetone, N,N-dimethylformamide, dimethyl sulfoxide, benzoyl peroxide, lauroyl peroxide, cumene hydroperoxide, tertiary butyl hydroperoxide, dicumyl peroxide, azobisisobutyronitrile, etc. catalysts can be used.

Thereafter, the copolymer thus obtained is neutralized with an alkali to produce a copolymer salt. At this time, the alkali used is preferably sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium carbonate, ammonia, sodium acetate, urea, thiourea, organic amines, etc. The reaction temperature of this neutralization reaction is 20 ~
150℃.

The reaction time is preferably set to 0.5 to 10 hours.

The coating agent of the present invention contains the salt of the above-mentioned ternary copolymer and water as essential components, and the amounts of both are not particularly limited.

100 to 20 parts of water per 100 parts by weight of the ternary copolymer
It is preferable to set the amount to 00 parts by weight, more preferably 200 to 1000 parts by weight.

Furthermore, in addition to the above-mentioned essential components, the coating agent of the present invention may optionally contain titanium oxide, calcium carbonate,
Inorganic fillers such as barium sulfate, zinc oxide, aluminum oxide, magnesium oxide, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, talc, clay;
polyvinyl alcohol, carboxymethylcellulose,
It may contain water-soluble resins such as hydroxymethylcellulose, hydroxyethylcellulose, starch, glue, and sodium polyacrylate; plasticizers such as dioctyl phthalate, dibutyl phthalate, di(2-ethylhexyl) adipate, and tricresyl phosphate.

The coating agent of the present invention obtained as described above is
It can be applied to various materials such as metal, wood, glass, paper, plastics, asbestos, and concrete as a coating agent for surface protection such as rust prevention, waterproofing, adhesive base, and scratch prevention.

[Examples] Examples 1 to 4 Into an autoclave with an internal volume of 11, the indicated amounts of the indicated components except for inbutylene were charged, and the autoclave was cooled to -10°C, and the inside of the container was sufficiently degassed. Next, the indicated amount of imbutylene, 480 cc of acetonitrile as a solvent, and 0.6 g of benzoyl peroxide as a catalyst were added, and the mixture was heated at 110°C.
A copolymerization reaction was carried out for 2 hours, and then the product was poured into water to obtain a copolymer. The number average molecular weight, acid value (gKOH/g), amount of styrene (% by weight), and amount of methyl acrylate (% by weight) of the obtained copolymer are shown in the table.

Thereafter, an amount of sodium hydroxide aqueous solution was added to the copolymer in an amount that would give a neutralization degree of 1 to bring the concentration to 20% by weight.
A neutralization reaction was carried out at 90° C. for 6 hours to produce a copolymer salt, thereby obtaining a coating agent of the present invention.

The coating agent thus obtained was coated with an inner diameter of 90
A coating film was formed by spreading the mixture to a thickness of 1 g on a Petri dish, and the weight loss rate was measured every hour after being left in the air. Further, the drying time to the touch of this coating film was measured in accordance with JIS K 5400, and the above results are shown in the table.

Example 5 A mixture of the copolymers obtained in Examples 2 and 4 above at a weight ratio of III was used as the copolymer.
After producing coating agents in the same manner as in Examples 1 to 4 above, similar evaluation tests were conducted and the results are shown in the table.

Comparative Example 1 A copolymer and a coating agent were produced in the same manner as in Examples 1 to 4 above, except that only the two indicated components were used as copolymerization components, and the same evaluation tests were conducted to obtain the results. Shown in the table.

Comparative Example 2 In the copolymerization reaction, n-butyl acetate was used as a solvent,
Except that azobisisobutyronitrile was used as a catalyst, the temperature of one reaction was 55°C, and the reaction time was 8 hours.
After producing a copolymer Oyohi coating agent in the same manner as in Comparative Example 1 above, the same evaluation test was conducted and the results are shown in the table. Since the water in this coating agent evaporates quickly after application, the curing time including the water evaporation process can be significantly shortened compared to conventional coating agents, making it suitable for rust prevention of various materials such as metal, wood, and glass. It is extremely useful as a coating agent for waterproofing, adhesive base, or surface protection, and has great industrial value.

Claims (1)

[Claims] A coating agent characterized by containing a salt of isobutylene-maleic acid or its anhydride-styrene copolymer and/or a salt of isobutylene-maleic acid or its anhydride-acrylic acid compound copolymer; and water.