JPH01152166A - Alcohol-resistant coating composition - Google Patents

Abstract

PURPOSE:To obtain the present composition excellent in flexibility, strength, adhesion and alcohol resistance, by mixing a glycidyl ether epoxy resin having a polysulfide skeleton with an amine. CONSTITUTION:A glycidyl ether epoxy resin is reacted with a substance having a polysulfide skeleton of the formula -R-Sx (wherein R is an alkylene having at least one ether bond, x has an average of 1-3) in the presence of, optionally, a solvent such as toluene and a catalyst such as a tert. amine to obtain a glycidyl ether epoxy resin (A) having 50-90wt.% polysulfide skeleton. 100pts.wt. component A is mixed with 1-100pts.wt. amine (B) (e.g., diethylenetriamine) and, optionally, an antifloating agent, an antiskinning agent, a drying agent, a pigment, a dispersant, etc.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an alcohol-resistant coating composition, and more specifically, it relates to an alcohol-resistant coating composition that is highly flexible, strong, has good adhesion, and has excellent alcohol resistance. This invention relates to an alcohol-resistant paint composition.

[Conventional technology]

Epoxy resins have excellent adhesive properties, chemical resistance, and durability, and are therefore used in fields such as paints, electrical/electronic parts, and adhesives. Compared to various synthetic resin paints,
Epoxy resin paints have excellent performance and are widely used as paints for cans, automobiles, ships, heavy-duty anti-corrosion paints, chemical-resistant paints, etc. However, conventional epoxy resin paints lack flexibility and are prone to peeling from the material and cracking of the paint film.

As a method of imparting flexibility to an epoxy resin, a method is known in which a urethane skeleton, a glycol skeleton, or a nitrile rubber skeleton is introduced into the epoxy resin to produce a flexible epoxy resin. However, the introduction of a urethane skeleton, glycol skeleton, or nitrile rubber skeleton greatly reduced the alcohol resistance of epoxy resins, and these flexible epoxy resins could not be used as alcohol-resistant coating compositions.

Furthermore, it is known that by mixing a polysulfide polymer with an epoxy resin, a cured epoxy resin product with appropriate flexibility can be obtained.

[Problem that the invention seeks to solve]

However, since polysulfide polymers have a unique mercaptan odor, epoxy resin compositions containing polysulfide polymers have tended to be avoided for use as paints.

Accordingly, an object of the present invention is to provide a coating composition that has good flexibility, strength, and adhesion as well as excellent alcohol resistance.

[Means for solving problems]

In view of the above-mentioned problems, the inventors of the present invention have made extensive studies on paint compositions with good alcohol resistance, and found that by using glycidyl ether-based epoxy resins with polysulfide bonded to the skeleton and amines as main components, It has been discovered that an alcohol-resistant coating composition that is highly flexible, strong, has good adhesion, and has excellent alcohol resistance and has no mercaptan odor has been developed, and the present invention has been conceived.

That is, the alcohol-resistant coating composition of the present invention has (A)
It is characterized by containing a glycidyl ether-based epoxy resin having a polysulfide skeleton and (B) an amine.

The epoxy resin used in the present invention is an epoxy resin in which a polysulfide skeleton is introduced into a glycidyl ether type epoxy resin.

Examples of the glycidyl ether epoxy resin in the present invention include bisphenol A epoxy resin, bisphenol AD epoxy resin, and halogenated bisphenol A epoxy resin.
type epoxy resin, bisphenol F type epoxy resin, halogenated bisphenol F type epoxy resin, novolak type epoxy resin, etc., or those having a molecular structure similar to these. Glycidyl ether-based epoxy resin generally has epoxy groups at both ends.

The polysulfide skeleton contained in the glycidyl ether-based epoxy resin in the present invention is expressed by the general formula: % (wherein, R is an alkylene group having at least one ether bond, and the average of x is 1 to 3). expressed.

Preferably, the polysulfide skeleton is represented by the general formula: % (L, R+, L, R8 are alkylene groups having 1 to 4 carbon atoms, and the average of X is 1 to 3). Note that the preferable average value of X is 1.5 to 2.5.

A particularly preferred polysulfide skeleton is -C2H4
0CH20C2H, -3X- (however, the average of X is 1.
5 to 2.5. ).

The epoxy resin in the present invention can be produced, for example, by reacting a glycidyl ether-based epoxy resin with a substance having a polysulfide skeleton.

It can also be produced by reacting a substance with a polysulfide skeleton with epichlorohydrin and then causing a dehydrochlorination reaction with an alkali.

The reaction between the polysulfide polymer and the glycidyl ether epoxy resin is preferably carried out in a state where the glycidyl ether epoxy resin is in excess.

The epoxy resin in the present invention can be produced by a method using a solvent such as toluene, a method using a catalyst such as tertiary amines, or a method of reaction without a solvent or catalyst. Epoxy resins manufactured by can also be used in the present invention.

The content of polysulfide skeleton in the epoxy resin in the present invention varies depending on the purpose of use. If a relatively soft coating film is desired, the content of polysulfide skeleton is increased, for example, from 50% to 90% by weight. In addition, if a relatively hard coating film is intended, the content of polysulfide skeleton should be reduced, for example, from 5% by weight to 5% by weight.
Make it 0% by weight. Therefore, it is generally preferable to control the content of polysulfide skeleton within the range of 5% by weight to 90% by weight. If the content of the polysulfide skeleton exceeds 90% by weight, the coating film becomes too soft and the strength decreases, which is not preferable. Further, if the content of the polysulfide skeleton is less than 5% by weight, the flexibility of the coating film decreases and cracks and creases are more likely to occur, which is not preferable. The more preferable polysulfide skeleton content is 8 to 8.
It is 80% by weight.

Note that the content of polysulfide skeleton can be controlled by appropriately selecting the molecular weight of the material having a polysulfide skeleton as a raw material. The content of polysulfide skeleton can also be controlled by appropriately selecting the molecular weight of the glycidyl ether epoxy resin. Alternatively, the content of the polysulfide skeleton can also be controlled by selecting the reaction ratio between the substance having the polysulfide skeleton and the glycidyl ether epoxy resin or epichlorohydrin.

In the present invention, amines are blended as a curing agent.

Examples of amines used in the present invention include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, influoronediamine, cyclohexylamine, 1,2-diaminocyclohexane, 1,3-bis(amino 4. Methyl)cyclohexane, bis(4-amino-3-methylcyclohexyl)methane, m-xylene diamine, N-aminoethylpiperazine, p, p'-diaminodiphenylmethane, diaminodiphenylsulfone, m-phenylenediamine, 4. 4°-methylene dianiline, N-benzylethylenediamine, 1-(2-aminoethyl>piperazine,
N, N-diethylamino-m-propylamine, N,
N, N', N'-tetramethylhexamethylenediamine, piperidine, menthanediamine, benzyldimethylamine, dimethylaminomethylphenol, 2.4
．． 6-tris(dimethylaminomethyl)phenol, D
BU, polyamine epoxy resin adduct produced by reacting epoxy resin with excess amine, polyamine-ethylene oxide adduct, polyamine-propylene oxide adduct, cyanoethylated polyamine, ketamine, or polyamines and phenols, aldehydes, etc. Dehydrated condensate obtained by reaction, 2-ethyl-4
-Imidazoles such as methylimidazole, etc. can be mentioned.

In the present invention, the amount of amines to be blended varies depending on the type of amines, but is generally 1 to 100 parts by weight, preferably 2 to 80 parts by weight, based on 100 parts by weight of the epoxy resin.

The alcohol-resistant coating composition of the present invention is mainly composed of a glycidyl ether-based epoxy resin having a polysulfide skeleton and an amine, but if necessary, compatible or compatible substances such as a reactive diluent may be added. Can be added.

Furthermore, in the alcohol-resistant coating composition of the present invention,
Zinc white, aramid fiber, mica powder, yellow lead,
Zinc octylate, carbon fiber, carbon black, glass lll fiber, glass flakes, kaolin, clay, ultramarine blue, chromium oxide, titanium oxide, silica, fatty acid amide,
Aluminum hydroxide, hydrogenated castor oil, zinc stearate, quartz powder, talc, calcium carbonate, precipitated barium sulfate, iron black, xylene, toluene, pallite powder, phthalocyanine green, phthalocyanine blue, red iron, benzotriazole, polyethylene wax, Anti-color separation agents such as methyl isobutyl ketone and organic bentonite, anti-skinning agents, desiccants, pigments, dispersants, ultraviolet absorbers, antifoaming agents, fillers, thickeners, extenders, anti-sagging agents, anti-settling agents. agent, emulsifier, viscosity stabilizer, reinforcing agent, solvent, deterioration inhibitor,
Flame retardants and the like can be added.

〔Example〕

Next, the present invention will be explained in more detail with reference to Synthesis Examples, Examples, and Comparative Examples.

Synthesis Example 1 In a 1 liter separable flask, add bisphenol A.
Type epoxy resin (manufactured by Asahi Denka Kogyo ■ ADEKA RESIN BP-
4100'') and 150 g of a polysulfide polymer with a molecular weight of 1000 and an S content (average of It was confirmed that all the polysulfide polymers reacted with bisphenol A type epoxy resin.The epoxy equivalent at this time was 3.
42, the viscosity was 645 poise (25°C), and the reaction product had no mercaptan odor.

Example 1 The method for measuring alcohol resistance is JIS K 540.
0 (1979) rPaints/General Test Methods.

100 parts by weight of the epoxy resin of Synthesis Example 1 and additives were mixed in the following proportions to form a main ingredient.

Epoxy resin of Synthesis Example 1 100 parts by weight Titanium dioxide 50 parts by weight Calcium carbonate
30 parts by weight of organic bentonite) 0.5 parts by weight 5 parts by weight of triethylenetetramine was used as a hardening agent, and the mixture was applied to an iron plate. After curing at room temperature for 7 days, it was soaked in methanol for 2 weeks at room temperature. The test piece was taken out and left at room temperature for 1 hour, and then the state of the coating film was observed. The results are shown in Table 1.

As shown in Table 1, no blistering, cracking, peeling, softening, or elution was observed in the coating film, and no abnormalities were observed after immersion in methanol. It can be seen that the methanol resistance is better than that of Comparative Example 1, which will be described later.

The method for measuring bending resistance is JIS K 5400 (197
9) The general test method for paints was followed.

After mixing the base resin and curing agent, the mixture was applied to a tin plate having a thickness of Q and 3 mm. After curing at room temperature for 7 days, flex resistance was measured at room temperature using a flex tester. The results are shown in Table 1. As shown in Table 1, even under the most severe conditions in the bending resistance test (when the diameter of the mandrel was 2 mm), no cracking or peeling was observed in the coating film, and the bending resistance was good. Compared to Comparative Example 1, which will be described later, no abnormality was observed in the coating film even under severe conditions, indicating that the coating film had good bending resistance.

Comparative Example 1 100 parts by weight of a bisphenol A type epoxy resin ("Adeka Resin BP-4100" manufactured by Asahi Denka Kogyo ■) and additives were mixed in the following proportions to form a main resin.

Bisphenol A type epoxy resin 100 parts by weight Titanium dioxide 50 parts by weight Calcium carbonate 30 parts by weight Organic bentonite)
After forming a coating film in the same manner as in Example 1 using 0.5 parts by weight and 9 parts by weight of triethylenetetramine as a curing agent, the methanol resistance was measured. The results are shown in Table 1.

As shown in Table 1, peeling occurred in the coating film, indicating poor methanol resistance.

Furthermore, the bending resistance was measured in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, even under the most gentle conditions in the bending resistance test (when the diameter of the mandrel was 1Q mm), cracking and peeling occurred in the coating film, and the bending resistance was poor.

Example 2 In Example 1, 23 parts by weight of modified aliphatic polyamine (Adeka Hardener EH-230 manufactured by Asahi Denka Kogyo ■) was used instead of triethylenetetramine, and Example 1
A coating composition was produced in the same manner as above, and the methanol resistance of the resulting coating film was measured.

The results are shown in Table 1. As shown in Table 1, the methanol resistance was better than that of Comparative Example 2 described below.

Furthermore, the bending resistance was measured in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, even under the most severe conditions in the bending resistance test (when the diameter of the mandrel was 2 mm), no cracking or peeling was observed in the coating film, and the bending resistance was good. Compared to Comparative Example 2 described later, no abnormality was observed in the coating film even under severe conditions, and the bending resistance was good.

Comparative Example 2 In Comparative Example 1, 40 parts by weight of modified aliphatic polyamine (Adeka Hardener EH-230 manufactured by Asahi Denka Kogyo ■) was used in place of triethylenetetramine.
A coating composition was produced in the same manner as above, and the methanol resistance of the resulting coating film was measured.

The results are shown in Table 1. As shown in Table 1, blistering occurred in the coating film, indicating poor methanol resistance.

Furthermore, the bending resistance was measured in the same manner as in Comparative Example 1. The results are shown in Table 1. As shown in Table 1, even under the most gentle conditions in the bending resistance test (when the diameter of the mandrel was lQmn+), cracking and peeling occurred in the coating film, and the bending resistance was poor.

Synthesis Example 2 Put the polysulfide polymer into a 1 liter separable flask and add "Thiokol LP-3" made by Thiokol.
Add 93g and 165g of bisphenol F type epoxy resin (Adeka Resin BP-4901 manufactured by Asahi Denka Kogyo ■),
After stirring at 90° C. for 10 hours, it was confirmed that all the polysulfide polymer had reacted with the bisphenol F type epoxy resin. The epoxy equivalent at this time is 330,
The viscosity was 280 poise (25°C), and the reaction product had no mercaptan odor.

Example 3 100 parts by weight of the epoxy resin of Synthesis Example 2 and additives were mixed in the following proportions to form a main ingredient.

Epoxy resin of Synthesis Example 2 100 parts by weight Titanium dioxide 50 parts by weight Calcium carbonate
30 parts by weight of organic bentonite 0.5 parts by weight A coating composition was produced using 10 parts by weight of l-xylene diamine as a curing agent, and Example 1 was conducted for the resulting coating film.
Methanol resistance was measured in the same manner as above. Similarly, ethanol resistance and ethylene glycol resistance were measured under the same conditions. The results are shown in Table 2. As shown in Table 2, no abnormality was observed in the coating film, and the alcohol resistance was good.

Furthermore, the bending resistance was measured in the same manner as in Example 1. The results are shown in Table 2. As shown in Table 2, even under the most severe conditions in the bending resistance test (when the diameter of the mandrel was 2 mm), no cracking or peeling was observed in the coating film, and the bending resistance was good.

Synthesis Example 3 Add bisphenol A type epoxy resin (Adeka Resin BP- manufactured by Asahi Denka Kogyo ■) to a 1 liter separable flask.
Add 200 g of polysulfide polymer "Thiokol LP-3" (manufactured by Kutoshi Thiokol ■) and stir at 90°C for 20 hours to confirm that all the polysulfide polymer has reacted with the bisphenol A epoxy resin. was confirmed.The epoxy equivalent at this time was 59
The reaction product had no mercaptan odor.

Example 4 100 parts by weight of the epoxy resin of Synthesis Example 3 and additives were mixed in the following proportions to form a main ingredient.

Epoxy resin of Synthesis Example 3 100 parts by weight Titanium dioxide 50 parts by weight Calcium carbonate
A coating composition was prepared in the same manner as in Example 1, using 30 parts by weight of organic bentonite and 0.5 parts by weight of 14 parts by weight of modified aliphatic polyamine (Reac CA-681 manufactured by Sanyo Chemical Industries, Ltd.) as a curing agent. The methanol resistance of the resulting coating film was measured.

Ethanol resistance and ethylene glycol resistance were also measured in the same manner. The results are shown in Table 2. As shown in Table 2, no abnormality was observed in the coating film, and the alcohol resistance was good.

Furthermore, the bending resistance was measured in the same manner as in Example 1. The results are shown in Table 2. As shown in Table 2, even under the most severe conditions in the bending resistance test (when the diameter of the mandrel was 2 mm), no cracking or peeling was observed in the coating film, and the bending resistance was good.

Table 1 Table 2 [Effects of the Invention] As detailed above, since the alcohol-resistant paint composition of the present invention contains a glycidyl ether-based epoxy resin having a polysulfide skeleton as its main component, it has excellent alcohol resistance and chemical resistance. It has excellent strength, flexibility, toughness, abrasion resistance, and durability. Furthermore, since the alcohol-resistant coating composition of the present invention does not contain any component having a mercaptan odor, its uses are not limited by odor.

The alcohol-resistant paint composition of the present invention having the above characteristics can be used as a paint for cans, a paint for ships, a paint for civil engineering and construction, and the like.

Claims (1)

[Claims] An alcohol-resistant coating composition comprising (A) a glycidyl ether-based epoxy resin having a polysulfide skeleton and (B) an amine.