JP2000026769A - Thick anticorrosion coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thick anticorrosion coating composition hardly causing problems on safety and hygiene, and having improved compatibilities of an epoxy resin and an amine-based hardening agent with a petroleum-based resin. SOLUTION: This thick anticorrosion coating composition comprises (A) an epoxy resin, (B) an amine-based hardening agent, and (C) a reaction product of an aromatic hydrocarbon-formaldehyde resin with the epoxy resin, and contains 20-200 pts.wt. component C without the solvent based on 100 pts.wt. total of the components A and B. The thick anticorrosion coating composition also comprises (A) the epoxy resin, (B) the amine-based hardening agent, (C) the reaction product of the aromatic hydrocarbon-formaldehyde resin with the epoxy resin, and (D) a petroleum-based resin having 50-150 deg.C softening point, and contains 20-500 pts.wt. total of the components C and D based on 100 pts.wt. total of the components A and B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anticorrosion paint composition containing no tar, particularly useful for coating the interior of ships such as ballast tanks.

[0002]

2. Description of the Related Art Conventionally, tar epoxy paints have been used as anticorrosion paints for ships and steel structures. Although the paint is excellent in corrosion resistance, water resistance, chemical resistance, etc., since it contains tar, there is a problem in safety and hygiene due to benzopyrene (carcinogenic substance) contained in the tar. Not only was there a concern, but the black color made it difficult to maintain and manage, and it became dark in a closed place, causing problems such as danger of work. In recent years, non-tar paints using petroleum-based resins instead of tars have been developed. However, such paints are not suitable for compatibility between petroleum-based resins and cured resins composed of epoxy resins and amine curing agents. There is a problem, and it is not enough to be applied to a ballast tank of a ship that requires high corrosion resistance and water resistance.

[0003]

SUMMARY OF THE INVENTION The present invention overcomes the above-mentioned disadvantages of the conventional method and has no problem in terms of safety and health and has improved the compatibility between an epoxy resin and an amine curing agent and a petroleum resin. It is a composition for anticorrosion paints.

[0004]

The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, have found that a reaction product of an aromatic hydrocarbon formaldehyde resin and an epoxy resin, or a petroleum resin and an aromatic hydrocarbon formaldehyde. By using a combined system of resin and epoxy resin reactant, it is safe while maintaining compatibility with epoxy resin and amine curing agent, aromatic hydrocarbon formaldehyde resin and epoxy resin reactant and petroleum resin. The present inventors have found that an anticorrosion coating composition which is excellent in corrosion resistance, water resistance and adhesion and has a hygiene problem and can form a light-colored coating film as compared with tar is obtained.

That is, the present invention relates to (A) an epoxy resin,
(B) an amine-based curing agent, and (C) a reaction product of an aromatic hydrocarbon formaldehyde resin and an epoxy resin,
A composition for a heavy-duty anticorrosive paint, comprising 20 to 200 parts by weight of (C) excluding the solvent with respect to 100 parts by weight of (A) + (B) excluding the solvent, and (A) an epoxy resin , (B) an amine-based curing agent, (C) a reaction product of an aromatic hydrocarbon formaldehyde resin and an epoxy resin, and (D)
It consists of a petroleum resin having a softening point of 50 to 150 ° C. and contains 20 to 500 parts by weight of the total of (C) + (D) excluding the solvent with respect to 100 parts by weight of (A) + (B) excluding the solvent. The present invention provides a heavy-duty anticorrosive paint composition characterized by the following:

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The epoxy resin (A) used in the present invention has at least two or more epoxy groups in one molecule and has an epoxy equivalent of 150 to 900, preferably 15 to 900.
A range of 0 to 500 is suitable. Examples of such epoxy resins include bisphenol type epoxy resins, aliphatic epoxy resins, glycidyl ester type epoxy resins, glycidylamine type epoxy resins, phenol novolak type epoxy resins, cresol type epoxy resins, and dimer.
Conventionally known ones such as an acid-modified epoxy resin may be mentioned, and these may be used alone or in combination of two or more.

As the amine curing agent (B) used in the present invention, a conventionally known curing agent for epoxy resin, for example, 1,
3-bisaminomethylbenzene, isophoronediamine,
Aliphatic polyamines such as diethylenetriamine, triethylenetetramine, diaminodiphenylmethane, alicyclic polyamines, and aromatic polyamines; epoxy resin adducts, polyamidoamines, and polyamide resins of the polyamine; Two or more kinds can be used in combination. Among these, aliphatic polyamines having an aromatic ring are preferred from the viewpoint of compatibility with a reaction product of an aromatic hydrocarbon formaldehyde resin and an epoxy resin, and compatibility with a petroleum resin, and reactivity with an epoxy resin. 3-
A resin adducted with a Mannich base obtained by modifying bisaminomethylbenzene with phenol or alkylphenol and formalin or an epoxy resin is most suitable.

The mixing ratio of the above components (A) and (B) is
Although it is appropriately selected depending on the type of use of both, it is usually preferable that the equivalent ratio of [active hydrogen equivalent in (B) / epoxy equivalent in (A)] be in the range of 0.5 to 1.0. Appropriate.

The reaction product (C) of the aromatic hydrocarbon formaldehyde resin and the epoxy resin used in the present invention is obtained by converting an aromatic hydrocarbon formaldehyde resin and a bisphenol type epoxy resin into an acid catalyst such as P-toluenesulfonic acid or phosphoric acid. It can be obtained by reacting in the presence or by reacting an aromatic hydrocarbon formaldehyde resin, a bisphenol type epoxy resin and bisphenol A in the presence of an amine catalyst such as 2-ethyl 4-methylimidazole. The modification ratio of the aromatic hydrocarbon formaldehyde resin and the bisphenol-type epoxy resin can be freely selected in a weight ratio of 3/7 to 7/3. When the proportion of the aromatic hydrocarbon formaldehyde resin is reduced from 3/7, the epoxy resin
The compatibilizing action for the curing agent is reduced, which is not preferable.
If the proportion of the aromatic hydrocarbon formaldehyde resin is increased from 7/3, the compatibilizing action with respect to the epoxy resin base material and the curing agent also decreases, which is not preferable.

The petroleum resin (D) used in the present invention is, for example, an aromatic petroleum resin obtained by polymerizing a C9 fraction such as a styrene derivative or indene from heavy oil produced by petroleum naphtha cracking. Petroleum resin obtained by copolymerizing a C5 fraction and a C9 fraction, aliphatic petroleum resin obtained by partially cyclopolymerizing a conjugated diene such as cyclopentadiene and 1,3-pentadiene, and aromatic petroleum resin And alicyclic petroleum resins obtained by polymerizing dicyclopentadiene.

The reaction product (C) of the aromatic hydrocarbon formaldehyde resin and the epoxy resin excluding the solvent is a total amount of the epoxy resin (A) excluding the solvent and the amine curing agent (B) of 1
The content is preferably 20 to 200 parts by weight with respect to 00 parts by weight, and if less than 20 parts by weight, the flexibility is poor, and
When the amount is more than 00 parts by weight, the temperature difference water resistance and the seawater resistance are inferior, which is not preferable. The total amount of the reaction product (C) of the aromatic hydrocarbon formaldehyde resin and the epoxy resin excluding the solvent and the petroleum-based resin (D) having a softening point of 50 to 150 ° C. excluding the solvent is calculated based on the epoxy resin (A) excluding the solvent. ) And the amine-based curing agent (B) are preferably contained in an amount of from 20 to 500 parts by weight based on 100 parts by weight, and if the amount is less than 20 parts by weight, the flexibility is poor. Poor water resistance and seawater resistance are not preferred.

In the composition of the present invention, from the viewpoint of imparting flexibility, other liquid modifiers, for example, aromatic hydrocarbon formaldehyde resins such as xylene resin, mesitylene resin and toluene resin; butyl glycidyl ether, etc. A non-reactive diluent such as a monoepoxy compound and a non-reactive diluent such as a phenol-modified polycondensate may be added in a range of 50 parts by weight or less based on 100 parts by weight of the composition of the present invention.
Of these, aromatic ones are preferably used from the viewpoint of maintaining water resistance.

The composition of the present invention may further contain, if necessary, pigments such as extender pigments, rust preventive pigments, coloring pigments, etc .; reactive diluents; organic solvents, anti-settling agents, anti-sagging agents, wetting agents,
A usual paint additive such as a reaction accelerator, an adhesion-imparting agent, and a dehydrating agent may be appropriately contained.

The composition of the present invention is a two-pack type paint comprising a main agent containing an epoxy resin and an amine-based curing agent, and is usually applied on a primary rust preventive coating such as a zinc primer. Conventional methods such as air spray, airless spray, brush coating, and roller can be adopted as the method of applying the paint, and the paint can be applied to a dry film thickness of 150 to 300 μm. .

[0015]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. “Parts” and “%” are “parts by weight” respectively.
And "% by weight".

Production Example 1 500 g of Epicoat 828 as an epoxy resin, 500 g of Nicanol L (xylene resin manufactured by Mitsubishi Gas Chemical Co., Ltd.) and 220 g of xylene as an aromatic hydrocarbon formaldehyde resin were placed in a 2 L separable flask equipped with a Deinstalk trap. 80 g of butanol and 80 g
The mixture is stirred for 1 hour at the above temperature to dissolve uniformly. 20 g of P-toluenesulfonic acid is dissolved and added in 20 ml of water, and the mixture is reacted at reflux temperature for 3 hours while draining water. Viscosity 90
(Cp / 25 ° C.), 1320 g of a resin having a nonvolatile content of 73.4% and an epoxy equivalent of 830 was obtained. This resin is referred to as resin E.

Production Example 2 500 g of Epicoat 1001, 500 g of Nicanol L (xylene resin manufactured by Mitsubishi Gas Chemical Co., Ltd.), 360 g of xylene, and 180 g of butanol were charged into a 2 L separable flask equipped with a Deinstalk trap at 80 ° C. Stir for an hour to dissolve uniformly. 4 g of 85% phosphoric acid in 5 ml
The reaction is carried out at reflux temperature for 3 hours while draining water. 1545 g of a resin having a viscosity of 200 (cp / 25 ° C.) and a nonvolatile content of 63% and an epoxy equivalent of 2430 were obtained. This resin is referred to as resin F.

Production Example 3 380 g of Epikote 828 in a 2 L separable flask
, 114 g of bisphenol A, 494 g of Nicanol L (xylene resin manufactured by Mitsubishi Gas Chemical Co., Ltd.) and 0.3 g of 2-ethyl-4-methylimidazole are charged and reacted at 150 ° C. for 2 hours. Thereafter, the temperature was lowered to 100 ° C.
2 g butanol 212 g was added, and the viscosity 700 (c
p / 25 ° C), nonvolatile content 67.5%, epoxy equivalent 1,
1410 g of 570 resin were obtained. This resin is referred to as resin G.

Production Example 4 Into a 1 liter container, 33 parts of epoxy resin (Note 1), 70 parts of titanium white, 100 parts of talc, 136 parts of resin (E) and 20 parts of xylene were added, mixed with a disper, stirred and dispersed. To make the main ingredient, to which amine curing agent (H) (Note 2) 80
Was added immediately before coating, and mixed and stirred to obtain an anticorrosive paint. (Note 1) "Epicoat 1001X75": Epoxy equivalent of solids: 475, 75% xylene solution, manufactured by Yuka Shell Epoxy Co., Ltd. (Note 2) Amine-based curing agent (H): Versamide 230X
B60: Polyamide-based curing agent Active hydrogen equivalent of solid 230, 60% solution Henkel Japan K.K. (Note 3) Quinton 1500: Dicyclopentadiene-based petroleum resin 50% xylene / butanol solution from Nippon Zeon K.K. (Note 4) Nicanol L: Xylene resin Used in a 70% xylene / butanol solution manufactured by Mitsubishi Gas Chemical Company, Inc. (Note 5) Amine-based curing agent (I): “Ditoclar X7
78 "Active hydrogen equivalent of solid content of Mannich-modified type curing agent of 1,3-bisaminomethylbenzene 70 Made by Daito Sangyo Co., Ltd. (Note 6) Tar epoxy paint: Eposeal 6000PS
Manufactured by Kansai Paint Co., Ltd.

Performance test: The anticorrosion paint obtained by the formulation of Production Example 4 was subjected to the following performance test, and the results are shown in Example 1 of Table 1. Tables 1 and 2 show the test results of Examples 1 to 8 and Comparative Examples 1 to 8 of the anticorrosion paints obtained by changing the formulation.
It was shown to.

(* 1) Flexibility: Each anticorrosive paint was applied to a degreased polished mild steel plate (150 × 70 × 0.8 mm) with an airless sprayer to a thickness of about 250 μm (dry film thickness). Each test coated plate was dried by drying in an atmosphere at 65 ° C. and 65% RH for 7 days. The coated plate was bent at 90 ° in an atmosphere of 25 ° with the coated surface outside, and the coating film at the bent portion was visually evaluated for cracks (の: no cracks, Δ: slightly cracked, ×: considerably cracked) ).

(* 2) Water resistance against temperature difference: Each anticorrosive paint obtained above was shot on a shot-blasted steel plate (300 × 100 × 3.2 mm) by airless spraying for about 2 hours.
Painted to 50 μm (dry film thickness), 25 ° C, 6
Each test coated plate was dried for 7 days in an atmosphere of 5% RH.
The coated surface of this test coated plate was heated to 40 ° C hot water,
After immersion for 14 days in an immersion tank in contact with water, the state of the coated surface was visually evaluated (○: no abnormality, Δ: blister,
The generation of rust is slightly recognized, and X: blister rust is remarkably generated).

(* 3) Seawater resistance: Each test coated plate obtained in the same manner as in (* 2) was visually immersed in seawater at 50 ° C. for 3 months, and the coated surface condition was visually evaluated (○: abnormal). None, Δ: slight occurrence of blisters, ×: significant occurrence of blisters)

[0024]

[Table 1]

[0025]

[Table 2]

[0026]

The anticorrosion coating composition of the present invention comprises a reaction product of an aromatic hydrocarbon formaldehyde resin and an epoxy resin instead of tar and a reaction product of an aromatic hydrocarbon formaldehyde resin and an epoxy resin and a petroleum resin. By using a specific amount of the mixture, the compatibility with the epoxy resin and the amine-based curing agent is good, and there is no problem on safety and health, and the anticorrosion property,
It is excellent in water resistance and adhesion, and can form a light-colored coating film as compared with tar, and is very useful as an anticorrosion paint for ships and steel structures.

Claims (6)

[Claims] 1. A composition comprising (A) an epoxy resin, (B) an amine-based curing agent, and (C) a reaction product of an aromatic hydrocarbon formaldehyde resin and an epoxy resin, excluding the solvent [(A) + (B) ] A composition for a heavy-duty anticorrosive paint, comprising 20 to 200 parts by weight of (C) excluding the solvent with respect to 100 parts by weight. 2. An epoxy resin, (B) an amine curing agent, (C) a reaction product of an aromatic hydrocarbon formaldehyde resin and an epoxy resin, and (D) a softening point of 50 to 150.
(A) +
(B)] The solvent was removed with respect to 100 parts by weight [(C) +
(D)] in a total amount of from 20 to 500 parts by weight. 3. The composition according to claim 1, wherein (B) is an epoxy adduct of 1,3-bisaminomethylbenzene or a Mannich base. (D) is a styrene derivative, indene,
3. The composition according to claim 2, which is one or a mixture of two or more resins obtained by polymerizing one of cyclopentadiene, 1,3-pentadiene and dicyclopentadiene. 5. The composition according to claim 1, wherein (C) is obtained by reacting an aromatic hydrocarbon formaldehyde resin with a bisphenol type epoxy resin under an acid catalyst. 6. The composition according to claim 1, wherein (C) is obtained by reacting an aromatic hydrocarbon formaldehyde resin with bisphenol A and a bisphenol-type epoxy resin under an amine catalyst.