JPS60110766A - Paint composition - Google Patents

Abstract

PURPOSE:To provide paint having excellent dryness and gloss, containing a cellulose derivative contg. copolymerizable double bonds and an acrylic graft copolymer. CONSTITUTION:A paint compsn. contains a cellulose derivative (A) obtd. by reacting a cellulose derivative with a mono- or diester of maleic or fumaric acid and a binder component (B) composed of an acrylic graft copolymer obtd. by copolymerizing a polymerizable monomer mixture contg. 20-50wt% styrene. Examples of the cellulose derivatives are cellulose acetate butyrate, cellulose acetate, and cellulose acetate propionate. It is desirable that the main chain moiety (excluding cellulose derivative) of said graft copolymer has a number-average MW of 1,000-15,000 and a glass transition temp. of 50-95 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a coating composition, and more particularly to a coating composition containing a specific acrylic Graph 1-copolymer as a binder component and having excellent drying properties and gloss.

Acrylic thermosetting paints or air-drying two-component urethane paints usually produce coatings with excellent gloss, hardness, water resistance, chemical resistance, weather resistance, etc., and are suitable for automobiles, vehicles, electrical equipment, furniture, etc. Widely used for painting enamel, fully bent sheets, etc. In addition to the property of providing a good appearance, fast drying properties are strongly desired for applications such as automobile repair.

Recently, the technology of blending cellulose derivatives to improve the drying properties of paints has been attracting attention, but in the case of acrylic paints, it is necessary to increase the styrene content in order to obtain high gloss and good chemical resistance. . However, since the drying property is several hundred, even if a cellulose derivative is blended with the acrylic resin, the high styrene content of the acrylic resin results in poor compatibility with the resin, resulting in poor appearance. Systems that do not contain cellulose derivatives have good appearance but poor drying properties.

As described above, dryness and appearance are contradictory issues and it has been difficult to achieve both.

However, in recent years, fields such as automobile repair, woodworking, ceramics, etc. that require dryness and appearance are becoming more and more popular.

JP-A-56-157463 discloses a room-temperature-drying coating composition containing as a vehicle component a modified vinyl copolymer obtained by copolymerizing cellulose acetate butyrate (hereinafter referred to as CAD) and a vinyl monomer. is shown, but
It is said that there is a limit to the amount of styrene that can be copolymerized. This method involves the conventional direct reaction of CAB and vinyl monomers, or reacting CAB with maleic acid, fumaric acid, acid anhydride, acid chloride, etc., and then reacting with vinyl monomers. This is because all of the methods described in 8105 and the like had poor graph 1 to ratios, and it was not possible to copolymerize more than a certain limit amount of styrene monomer, for example, more than 35 weight of all the monomers.

If cellulose derivatives can be efficiently incorporated into acrylic polymers to improve drying properties, and if the styrene content can be polymerized at a level higher than 20%, which is necessary for high gloss, it is possible to improve drying properties and appearance. It is expected that both problems will be solved simultaneously and a useful resin vehicle will be obtained.

The present inventors previously applied CAB to an acrylic polymer in graph 1-
As a means of oxidation, we focused on the acetate and butylene 1-ester bonds of CAD, and reacted mono- or diesters of fumaric acid and maleic acid with CAB to obtain a macromer with CAII having a copolymerizable double bond. He developed a method and discovered that the desired product could be obtained with a high grafting rate by copolymerizing the CAD macromer with a polymerizable monomer. A patent application was filed for a manufacturing method.

In the invention according to the above application, the grafting rate of CAH is increased,
The purpose is to obtain a resin composition that has good solubility and compatibility with solvents or other resins and does not become cloudy when formed into a coating, and the polymerizable monomer copolymerized with the CAB macromer is styrene. It was recognized as any vinyl monofilament having α,β-ethylenically unsaturated bonds for obtaining ordinary acrylic resins including acrylic resins. In subsequent research, the present inventors found that the same method could be applied not only to cellulose acetate butyrate but also to other cellulose esters such as cellulose acetate-1 and cellulose acetate propione-1 (hereinafter referred to as cellulose derivatives). ) and acrylic resins with a high styrene content, that is, styrene accounts for 20 to 50% of the monomers constituting the acrylic resin, and have been found to be particularly useful for obtaining a resin vehicle capable of providing a high-gloss coating surface.

Therefore, in the present invention, the monomer to be copolymerized with the cellulose derivative macromer is preferably 25% to 40%.
A polymerizable monomer containing % styrene is copolymerized with a cellulose derivative macromer, and the resulting styrene-rich cellulose derivative graph 1-acrylic copolymer is used as an essential component of the resin vehicle. be.

In addition to increasing the styrene content, it is desirable that the number average molecular weight of the main chain portion of the acrylic graft copolymer excluding the cellulose derivative is approximately 1,000 to 15,000. This is because if it is less than 1,000, the initial drying properties are poor, and if it exceeds 15,000, the flowability is poor and the appearance is poor, both of which are undesirable for the purpose of the invention. The glass transition temperature of the main chain resin is preferably within the range of 50 to 956C; below 50C, initial drying properties are low;
When the temperature exceeds 5°C, there is a tendency for weather resistance to deteriorate. Furthermore, although it is not an absolute condition, if the resin acid value is less than 2, the curing properties during crosslinking will be poor, and if it exceeds 20, the reaction will be too fast and there is a tendency to cause distortion, etc., so the design should be within the range of 2 to 20. Also, if the hydroxyl value is less than 50, the crosslinking density will be low, the reactivity will be slow and drying will be poor, and if it exceeds 150, the concentration will be too high.
It is preferable to set it to 150.

The coating composition of the present invention contains any organic or inorganic pigment used for top coating, intermediate coating, etc., and constitutes a stable dispersion system.

If desired, other resins, extender materials, ultraviolet absorbers, antioxidants, surface conditioners, wetting agents, and other arbitrary coating additives can be added to the coating composition.

The coating composition of the present invention obtained in this way has excellent drying properties based on cellulose and high styrene content, and has gloss, weather resistance, chemical resistance, etc., and is useful for a wide range of applications including automobile repair, woodworking, ceramics, etc. Thermosetting paint in the paint field, 2
Useful as liquid urethane paint, etc.

The present invention will be explained below with reference to Examples. Unless otherwise specified, parts and percentages in the examples are by weight.

CAB resin resin liquid 8-liquid production example 1 Cellulose acetate-1-butyrate “CAB
-551-0,2J (Eastman Chemical Prog 91
(manufactured by ~) and 500 parts of xylene were charged, the temperature was gradually raised, and after confirming that CAB had dissolved, 150 parts of monobutyl maleate, 1.0 part of dibutyltin oxide, and 100 parts of xylene were charged. The reaction was carried out under a temperature condition of 150°C by heating and stirring for about 7 hours while blowing nitrogen gas. After the reaction was completed, 500 parts of toluene, 500 parts of xylene, and 1,000 parts of butyl acetate were added to dilute the mixture to obtain a CAB resin solution having a double bond copolymerizable with other polymerizable monomers. The obtained resin solution was a transparent solution having a nonvolatile content of 20 parts, a viscosity of A2-A3, and a color number of 1.

Production Examples 2 to 4 of CAII Macromer CAD resin solutions of Production Examples 2 to 4 were obtained using the same method as Production Example 1 and the formulations shown in Table 1. The special values are shown at the bottom of Table 1.

Table 1 Production Example of CAr3 Grafted Acrylic Resin Solution 40 parts of the CAB resin solution obtained in Production Example 1 of ICAD resin solution, 25 parts of toluene, 25 parts of xylene, and 19 parts of butyl acetate were mixed with a thermometer, a stirrer, a reflux condenser, The mixture was charged into a reactor equipped with a nitrogen introduction tube and a dropping funnel, heated and stirred while introducing nitrogen gas, and when the temperature reached 120'C, the following mixed solution of vinyl monomer component and polymerization initiator was heated at a constant temperature of 120°C. The solution was added dropwise from the dropping funnel at a constant rate over 3 hours.

Thirty minutes after the completion of the dropwise addition, a mixed solution of 0.8 parts of tertiary-butylperoxy-2-ethylhexanoate and 7 parts of butyl acetate was added dropwise at a constant rate over a period of 30 minutes. 90 minutes after completion of dripping12
It was maintained at 0°C and the contents were taken out after cooling.

The obtained graft copolymer solution had a nonvolatile content of 50.2%.
It was a uniform and transparent solution with a viscosity of X and a color number of 1 or less.

Other resin properties are shown in Table 3.

Vinyl monomer component and polymerization initiator styrene・・・・・・・・・・・・・・・・・・・・・
......40.0 parts 2-hydroxyethyl methacrylate...16.2 parts Methacrylic acid...
・・・・・・・・・・・・・・・・・・0.6 parts Methyl methacrylate・・・・・・・・・・・・・・・3
2.0 parts Isobutyl methacrylate...
...1.5 parts n-butyl acrylate...
・・・・・・・・・9.7 parts tertiary-butylperoxy 2 ethylhexanoei 1-・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・ 2.0 Total 102.0 parts Production Examples 2 to 7 of CAB graft acrylic resin solution CAB grafted acrylic resin solutions 2 to 7 were obtained using the vinyl monomer components and polymerization initiators shown. The special values are shown in Table 3.

(Space below) Table 2 Production Examples 2 to 7 of CAD Grafted Acrylic Resin Solutions Comparative Production Example 1 25 parts of 1-toluene was added to a reactor equipped with a stirrer, thermometer, reflux condenser, nitrogen gas introduction tube, and dropping funnel. 25 parts of xylene and 9 parts of butyl acetate were charged, heated and stirred while introducing nitrogen gas, and when the temperature reached 120°C, the vinyl monomer component and polymerization initiator shown in Production Example 1 of CAB-grafted acrylic resin solution were added. 102 parts of mixed solution to 120'
A continuous layer was added from the dropping funnel under the C-foot over 3 hours.

Thirty minutes after the completion of the dropwise addition, a mixed solution of 0.8 parts of tertiary-butylperoxy-2-ethylhexanoate and 7 parts of butyl acetate was added in equal layers over a period of 30 minutes. 90 minutes after completion of dripping12
After holding at 0°C, rCAB -551-0,24
(Manufactured by Eastman Chemical Prodg 1-Company) 6 parts to 12
While heating at 0°C, a solution of 15 parts of xylene, 10 parts of toluene, and 15 parts of butyl acetate was added, stirred for 30 minutes, cooled, and the contents were taken out. The varnish properties and resin characteristics are shown in Table 5.

Comparative Production Example 2 In a reactor similar to that shown in Comparative Production Example 1, rcA[l
-551-0, 2 parts 6 parts, xylene 40 parts, toluene 3 parts
5 parts and 24 parts of butyl acetate were gradually heated while introducing nitrogen gas, and when CAD was dissolved and the temperature reached 120°C, mixed solution 1 of monomer and polymerization initiator shown in Example 1 was prepared.
02 was added in equal layers from the dropping funnel at 120° C. over 3 hours.

Thirty minutes after the completion of the dropwise addition, a mixed solution of 0.8 parts of monobutylperoxy-2-ethylhexanoate and 7 parts of butyl acetate was added in equal layers over a period of 30 minutes.

After the dropwise addition was completed, the temperature was maintained at 120°C for 90 minutes, and then cooled.
I took out the contents.

The varnish properties and resin characteristics are shown in Table 5.

Comparative production example 3 Cellulose acetate butyrate +-rcAB-sl+5
1-o, 2'' and 500 parts of xylene were charged, the temperature was gradually raised, and after confirming that cellulose acetate butylene 1- was dissolved, 150 parts of maleic anhydride, 1.0 part of dibutyltin oxide, and xylene were added. Prepare 100 copies,
After about 10 hours, 500 parts of 1-toluene, 500 parts of xylene and 1,000 parts of butyl acetate were added. A cellulose acetate butyrate resin solution was obtained.

The resulting resin solution was a transparent solution with a nonvolatile content of 20%, a viscosity of D, and a color number of 1.

40 parts of the obtained resin solution, 25 parts of toluene, 2 parts of xylene
5 parts and 19 parts of butyl acetate were placed in the same reactor as in Comparative Production Example 1, and heated and stirred while introducing nitrogen gas.
When the temperature reached °C, 102 parts of the mixed solution of the vinyl monomer component and polymerization initiator shown in CAB Graph 1 - Production Example 1 of Acrylic Resin Solution was added dropwise at a constant rate of 3 hours from the dropping funnel at 120 °C. did.

30 minutes after the completion of the dropwise addition, a mixed solution of 0.8 parts of tert-butylperoxy-2-ethylhexanoate and 7 parts of butyl acetate was added dropwise at a constant rate over 30 minutes. 120 minutes for 90 minutes after completion of dripping
After cooling, the contents were taken out.

The varnish properties and resin characteristics are shown in Table 5.

Varnish Comparative Production Examples 4 to 7 Varnish Comparative Production Examples 4 to 7 were obtained using the vinyl monomer components and polymerization initiators shown in Table 4 in the same manner as in 4-part production example 1 of CAB grafted acrylic resin.

Table 4 Example 1 Preparation of white paint CAB graph 1 - Preparation of acrylic resin solution Using the varnish obtained in Example 1, perform pigment dispersion using the following dispersion blend to create a self-dispersing paste, and then dissolve and blend to prepare a white primary color. Created paint.

Hoei N Hill Titanium White CR-95 (manufactured by Ishihara Sangyo Co., Ltd.)...27
．． Part 0 Varnish・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・1o, g part toluene...
・・Old...Old group old...-2't,'1hL45.0
Part J Zheng Qiu own iFI paste...eye/old...old eye...4
s, o part varnish・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・49.2 parts -75 (Sumitomo Bayer 5R) was diluted to a predetermined viscosity with a thinner having a ratio of toluene/xylene/butyl acetate = 1/1/l and spray-coated on a commercially available lacquer primer at 25°C. The coating film performance is shown in Table 6.

Examples 2 to 7 and Comparative Examples 2 to 7 White primary color paints were prepared and spray coated in the same manner as in Example I. The coating film performance is shown in Table 6.

(Margin below)

Claims (3)

[Claims] (1) A cellulose derivative having a copolymerizable double bond obtained by reacting a cellulose derivative with a mono- or diester of maleic acid or fumaric acid, and a polymerizable monomer in which at least 20 to 50% by weight is styrene. A coating composition containing as an essential component a binder component consisting of an acrylic graft copolymer obtained by copolymerization. (2) The number average molecular weight of the main chain portion of the acrylic graft copolymer excluding the cellulose derivative is approximately 1,000 to 15
．． 000 and a glass transition temperature of 50° to 95°C. (3) The composition according to claim 1 or 2, wherein the cellulose derivative is selected from the group consisting of cellulose acetate-1-, cellulose acetate-1-propione-1-, and cellulose acetate butyrate. (The coating composition according to claim 1, in which an isocyanate prepolymer is used as a curing agent in an equivalent ratio of NC010H in the range of 0.5 to 2.0.