JPH04154876A - Chipping resistant paint - Google Patents

Abstract

PURPOSE:To obtain the title pollution-free coating compound curable, at normal temperature, useful as an undercoat for back of floor of automobile, having chipping resistance and corrosion resistance, comprising a specific copolymer, a reactive silicon group-containing oxyalkylene polymer and a curing promoter as essential components. CONSTITUTION:The objective coating compound comprising (A) a copolymer composed of an acrylic acid alkyl ester monomer unit or/and a methacrylic acid alkyl ester monomer unit which contains a reactive silicon group and a molecular chain with 1-8C alkyl and an acrylic acid alkyl ester monomer unit or/and a methacrylic acid alkyl ester monomer unit which contains >=10C alkyl, (B) a reactive silicon group-containing oxyalkylene polymer and (C) a curing promoter (e.g. dibutyltin dilaurate) as essential components to give the objective coating compound.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is suitable for use as a paint, that is, an undercoat, used for chipping and rust prevention on the underside of automobiles, and is non-polluting and This invention relates to a novel chipping-resistant paint that cures at room temperature.

[Conventional technology]

In recent years, due to the extension of the service life of automobiles and the improvement in the level of rust prevention requirements, vinyl chloride plastisol-based chipping-resistant paint has been applied to the underside of automobiles, side seals, fuel tanks, front aprons, tire houses, etc., for example, by airless painting. Techniques for painting using equipment are known. Chipping resistance refers to damage to the exterior of a car that occurs when pebbles, gravel, etc. fly off the road surface while the car is running and collides with the car body (chipping), as well as suppressing the spread of rust when these scratches reach the underlying surface. refers to the ability to

Vinyl chloride plastisol has been the mainstream for this undercoat material (chipping-resistant paint) due to the balance of cost and performance. Since vinyl chloride plastisol is mainly composed of vinyl chloride resin, hydrochloric acid gas is generated during combustion treatment for the purpose of recycling metal materials after scrapped cars, causing acid rain. Particularly in Europe, it has been reported that environmental destruction caused by acid rain is having various adverse effects on the natural world. Therefore, it is an important and urgent issue to try to use chlorinated vinyl resins in many other materials, including undercoat materials (chip-resistant paints).

[Problem to be solved by the invention]

The present invention was invented in view of the above-mentioned current situation, and does not use vinyl chloride resin, has excellent chipping resistance and rust prevention, satisfies other performances required as an undercoat material, and is non-polluting. The purpose of the present invention is to provide a chipping-resistant paint that is hardenable at room temperature.

[Means to solve the problem]

In order to solve the above-mentioned problems, the chipping-resistant paint of the present invention contains (A) a reactive silicon group, and the molecular chain is substantially (1)
An acrylic acid alkyl ester monomer unit and (or) a methacrylic acid alkyl ester monomer unit having an alkyl group having 1 to 8 carbon atoms, and (2) an acrylic acid alkyl ester monomer having an alkyl group having 10 or more carbon atoms. (B) an oxyalkylene polymer having a reactive silicon group; and (C) a curing accelerator. .

Each of the above components itself is 0. Although it is disclosed in JP-A-63-112642, there is no teaching that this composition is suitably used as a chipping-resistant paint.

Here, the reactive silicon group is a silicon-containing functional group that can be crosslinked by forming a siloxane bond, and a representative example is the general formula (■): (wherein, R1 is a substituted or unsubstituted group having 1 to 20 carbon atoms. Substituted monovalent organic group or triorganosiloxy group, X is a hydroxyl group or a different or similar hydrolyzable group, a is an integer of 0, 1 or 2, b is an integer of 0, 1.2 or 3, a-2
and does not become b-3, a is an integer from 0 to 13). A preferable reactive silicon functional group from the point of view of economy and the like has the general formula (n) R'.

It is a group represented by Si

In the chipping-resistant paint of the present invention, the curing accelerator is 0.1 to 10 parts per 100 parts of the polymers (A) and (B).
It is used by mixing about 1 part. If this amount is less than 0.1 part, curing will be slow, and if it is more than 1-5 = 0 parts, storage stability will be poor.

Examples of the curing accelerator include organic tin compounds, acidic phosphoric acid esters, reaction products of acidic phosphoric acid esters and amines, saturated or unsaturated polyhydric carboxylic acids or their acid anhydrides, and organic titanate compounds. Can be mentioned.

Specific examples of the organic tin compound include dibutyltin dilaurate, dioctyltin maleate, dibutyltin naphthalate, stannous octylate, dibutyltin methoxide, dibutyltin diacetylacetonate, dibutyltin diversate, and the like.

Examples of organic titanate compounds include titanate esters such as tetrabutyl titanate, tetraisopropyl titanate, and triethanolamine titanate.

In addition, this chipping-resistant paint may contain diluents (phthalate ester plasticizers such as dioctyl phthalate and butylbenzyl phthalate, plasticizers such as epoxidized soybean oil, solvents such as methanol, ethanol, toluene, etc.) as necessary. , reactive diluents, fillers (heavy calcium carbonate, light calcium carbonate, colloidal calcium carbonate, kaolin, talc, silica, titanium oxide, aluminum silicate, magnesium oxide, zinc oxide, carbon black, glass balloon, plastic balloon, etc.) ), an fj imparting agent (such as a silane coupling agent such as aminosilane or epoxysilane), an anti-sag agent, a coloring agent, a preservative, an ultraviolet absorber, a light stabilizer, a moisture absorbent, etc. can be added.

Furthermore, in order to accelerate the curing of the chipping-resistant paint of the present invention,
Humidification, heating, etc. can also be performed as necessary.

[Effect]

The chipping-resistant paint of the present invention eliminates the problems of poor curing (undrying) and water resistance by actively utilizing the moisture present in the atmosphere, and does not necessarily require heat for the curing reaction. This makes it possible to reduce thermal energy. In addition, since vinyl chloride resin is not used, the working environment in the car painting process is greatly improved, and no harmful gases (chlorine gas, etc.) are emitted during the incineration process after a scrapped car, so there is no need to worry about pollution. It is something without.

〔Example〕

Examples of the present invention will be described below.

Synthesis Examples 1 to 5 According to Synthesis Examples 1 to 5 of JP-A-63-112642, (meth)acrylic acid ester polymers as shown in Table 1 were obtained.

(Margin below) 1/- Table 1 Notes in Table 1 are as follows.

*1: Acrylic ester S manufactured by Mitsubishi Rayon ■ *2: CI□, CI3 mixed alkyl methacrylate 1 manufactured by Mitsubishi Rayon ■
/-t*3: T-methacryloxypropyltrimethoxysilane*4: T-mercaptopropyltrimethoxysilane*5: azobisisobutyronitrile*6: T-methacryloxypropylmethyldimethoxysilane*7: T-mercapto Propylmethyldimethoxysilane *8: Based on GPC measurement.

Synthesis Examples 6 and 7 CH at the end of the molecule according to Synthesis Examples 8 and 9 of JP-A-63-112642.

Polyoxypropylene having (CHsO)zs i CHzCHzCHzO- group was obtained.

In each Example, adhesive compositions using the polymers of Synthesis Examples 2 to 5 instead of the polymer of Synthesis Example 10 were prepared and evaluated, and almost the same results as in each Example were obtained.

Example 1 A composition of the polymer of Synthesis Example 1 and the polymer of Synthesis Example 7 (3100 parts of a mixture of 50 parts of an acrylic polymer having a terminal silyl group and 50 parts of a polyether having a terminal silyl group, 50 parts of calcium carbonate, 0.5 parts of moisture absorbent,
Five parts of a silane coupling agent (adhesive agent) and two parts of a curing accelerator (Neostane U-100) were stirred using a Dalton mixer, and the mixture was defoamed and stirred under reduced pressure to obtain a sample. This sample could be diluted to any proportion with a common organic solvent and could be cured at room temperature.

In addition, we evaluated the coating performance of this chipping-resistant paint and
Shown in the table. As is clear from the results in the same table, this chipping-resistant paint has excellent chipping resistance and does not generate harmful hydrochloric acid gas when heated.

Example 2 Composition of the polymer of Synthesis Example 10 and the polymer of Synthesis Example 6 [using 3100 parts of a mixture of 50 parts of an acrylic polymer having a terminal silyl group and 50 parts of a polyether having a terminal silyl group, and The formulation was exactly the same as in Example 1, and a similar sample was obtained using the same procedure. This sample could also be diluted to any desired ratio with a common organic solvent and could be cured at room temperature. Furthermore, the coating film performance of this chipping-resistant paint was evaluated and is shown in Table 2. As is clear from the results in the same table, this chipping-resistant paint has excellent chipping resistance and does not generate harmful hydrochloric acid gas when heated.

Example 3 A sample was prepared using the same composition and procedure as in Example 1, except that Neostane-U-300 was used as a curing accelerator. This sample could be diluted with a solvent and heat cured. Furthermore, the coating film performance of this chipping-resistant paint was evaluated and is shown in Table 1 11-2. As is clear from the results in the same table, this chipping-resistant paint has excellent chipping resistance and does not generate harmful hydrochloric acid gas when heated.

Example 4 A sample was prepared using the same composition and procedure as in Example 2, except that Neostan-U-300 was used as a curing accelerator. This sample could be diluted with an alcohol-based solvent and cured by heating. Furthermore, the coating film performance of this chipping-resistant paint was evaluated and is shown in Table 2. As is clear from the results in the same table, this chipping-resistant paint has excellent chipping resistance and does not generate harmful hydrochloric acid gas when heated.

Comparative Example 1 A sample was prepared using the same composition and procedure as in Example 1, except that Kaneki MS Polymer 300 [polyether having a terminal silyl group] was used as the polymer composition. This sample could be diluted to any proportion with a common organic solvent and could be cured at room temperature. Furthermore, the coating film performance of this sample was evaluated and shown in Table 2. As is clear from the results in the same table, this sample does not generate harmful hydrochloric acid gas when heated, but its adhesive performance is low and its chipping resistance is also poor, so it was found that it could not be used as a chipping-resistant paint.

Comparative Example 2 Using a kneader mixer, 23 parts of vinyl chloride H, 28 parts of phthalate ester, 21 parts of heavy calcium carbonate, 15 parts of surface-treated calcium carbonate, 7 parts of blocked isocyanate, 2 parts of polyamide resin, and 4 parts of calcium oxide and mixed and dispersed. Then, defoaming under reduced pressure (80 mmHg),
A sample was prepared by stirring. This sample is a typical vinyl chloride plastisol-based chipping-resistant paint resin that has been conventionally used as an undercoat material. The coating performance of this sample was evaluated and shown in Table 2. As is clear from the results in the same table, this sample generates harmful hydrochloric acid gas when heated, its adhesion performance is not very high, and its chipping resistance is also poor. It was found that this was not suitable compared to the sample.

(Left below) Table 2 In Table 2, the amount of chlorine gas generated is determined by setting the sample in a sealed capacity and blowing dry air.
The sample was heated to 0°C12O, and the internal air was sucked into the gas detection tube for measurement.

〔Effect of the invention〕

As described above, the chipping-resistant paint of the present invention does not use vinyl chloride resin, is non-polluting, has room-temperature curability, has excellent chipping resistance and rust prevention, and has other properties necessary as an undercoat material. It has the great effect of satisfying performance and being extremely suitable as an undercoat material.

Patent Applicant Cemedine Co., Ltd. Procedural Amendment December 25, 1990 1. Indication of the case Japanese Patent Application No. 2-282782 2. Title of the invention Chipping-resistant paint 3. Person making the amendment Relationship to the case Patent applicant name Title Cemedine Co., Ltd. 4, Agent address: 203 Nikko Building, 1-4-26 Takanawa, Minato-ku, Tokyo 108 'ff (449,) 5031'''1°°'°
)#P! ! "c E"""〒"−°・i・１
) 6. Number of claims increased due to amendment No increase 7
, Subject of amendment Specification (4 ril of detailed description of the invention)
! I) 8. Details of the amendment as per the attached sheet.

8. Contents of the amendment (1) In the specification, page 5, lines 9 to 10, "a is an integer of 3 and is not a-2 and b-3, a is an integer from 0 to 13)" The statement "J" is corrected to "represented by an integer of 3, a=2 and b=3, where m is an integer from 0 to 18)".

(2) Table 1 amending Table 1 on page 9 of the same document as attached. Procedural amendment June 28, 1991

Claims (2)

[Claims] (1) (A) has a reactive silicon group, and the molecular chain is substantially (1)
An acrylic acid alkyl ester monomer unit and (or) a methacrylic acid alkyl ester monomer unit having an alkyl group having 1 to 8 carbon atoms, and (2) an acrylic acid alkyl ester monomer having an alkyl group having 10 or more carbon atoms. (B) an oxyalkylene polymer having a reactive silicon group; and (C) a curing accelerator. Chipping resistant paint. (2) The chipping-resistant paint according to claim (1), further comprising (D) a filler and (E) an adhesion promoter added to the components (A), (B), and (C).