JPS6119671A - Corrosion-resistant paint composition - Google Patents

Abstract

PURPOSE:To provide a corrosion-resistant paint compsn. for the interior of vessels, which has an excellent corrosion-resisting effect over a long period of time by simply treating substrates before coating, by blending a specified modified epoxy resin, a bituminous substance and a liquid synthetic rubber. CONSTITUTION:A modified epoxy resin (e.g. Adeka Resin EPX-880, a product of Asahi Denka Kogyo K.K.) obtd. by reacting an epoxy resin of formula I (wherein R1 is H, methyl; R2 is CH2, a group of formula II; n is 5-30) with an ester having neighboring hydroxyl groups derived from a polycarboxylic acid and a polyhydric alcohol or a polynuclear polyhydric phenol having neighboring hydroxyl groups in a solvent, is used. 30-600pts.wt. bituminous substance (e.g. soft to medium pitch having a coal tar content of 5-20% and a softening point of 50-60 deg.C) and 0-50pts.wt. liquid synthetic rubber (e.g. polyisobutylene having an MW of 200-50,000) are blended with 100pts.wt. said modified epoxy resin.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention provides a low-accumulative jtl+ system for completely preventing corrosion of the interior of ships made by @, such as ballast tanks, void spaces, cofertums, holds, and chain lockers.
The present invention relates to a controlled VI food paint composition.

(Conventional technology 9) There are anticorrosive paints for the interior of ships that are mainly composed of epoxy resins, urethane resins, vinyl resins, chlorinated rubber resins, bituminous substances, and pigments. It has excellent water resistance and corrosion resistance, and is widely used.

(Problem that the invention attempts to solve) 110 people However, in order to fully demonstrate sufficient performance, careful preparation of the substrate, such as sandblasting, Sl55m-2,5 or power tool treatment, 5ISSt-3, etc. is necessary. . Furthermore, the structure of the interior of a ship is complex and the scaffolding is poor, so scaffolding is sometimes necessary to ensure work safety, and the careful preparation of the surface described above requires a great deal of effort, time, and expense. The reality is that she has blonde hair.

Grease-like non-drying anticorrosive paints are paints that can be applied with simple preparation of the substrate, but they are not widely used because the paint film remains soft and easily damaged.

Is the purpose of the present invention to provide excellent corrosion protection over a long period of time through simple substrate preparation? I-An object of the present invention is to provide an anticorrosive paint that exhibits excellent corrosion resistance.

Another object of the present invention is to reduce the process tray width of progressive adjustment.

(Means for Solving All Problems) The polyhydric phenol-modified epoxy resin having adjacent hydroxyl groups used in the anticorrosive paint of the present invention can be used to prevent rust caused by iron hydroxide, iron oxide, etc. generated on the surface of the steel material to be coated. penetrates into
It forms a chelate with rust to stabilize the end metal and at the same time prevent the progress of rust. The state of this chelate formation is shown in Formula-1.

Formula-1 P: Indicates epoxy resin skeleton.

The polyhydric phenol group having a water-containing tR group in the modified epoxy tree has a reducing property, and has the effect of converting red rust into stable black rust as shown in Formula 2.

Formula-2 Felon '"no" group Fe104 (red rust
(Black Rust) In order to bond a polyhydric phenol group having adjacent hydroxyl groups to a total epoxy resin, a polyhydric phenol polyhydric alcohol ester having adjacent hydroxyl groups or (and/or)
A condensate of a polyhydric phenol having adjacent hydroxyl groups and formalin is reacted with an epoxy resin in a total solution.

Polyhydric phenol polyhydric alcohol esters having adjacent hydroxyl groups include polyhydric alcohols such as ethylene glycol, propylene glycol, butylene glycol, 1,6-hexanediol, glycerin, trimethylolpropane, benmeerythritol, sorbitol, glucose, etc. , catechol-3-carboxylic acid, catechol-4-carboxylic acid, gallic acid, m-digallic acid, pyrugalol-
Any combination of ester compounds with polyhydric phenol carboxylic acids such as 4-carboxylic acid, pyrogallol-4,6-dicarboxylic acid, and mendinine 11 can be used, but when these are reacted with the epoxy resin, Mononuclear phenol carboxylic acid esters such as salicylic acid ester and P-hydroxybenzoic acid ester may be mixed.

Polynuclear polyhydric phenol compounds having adjacent hydroxyl groups include catechol, catechol-3 (or 4)-carboxylic acid (or its ester), pyrogallol, pyrogallol-4-carbon a<t or its ester, pyrogallol-4,6 - dicarboxylic acid (or its ester),
Formalin condensates such as 3,4,5-t')oxybenzoic acid (or its esters), tannic acid (or its esters), and urushiol are used.Also, when condensing polyhydric phenols with formalin, phenol , mononuclear phenols such as cresol, hydroquinone, and salicylic acid may be mixed.

In order to improve waterproofness, it is essential to use a T* substance, which has a content of 30 to 60% based on the IOO part of the P1 modified epoxy resin.
0 autopsy, preferably 60-4008Il'iTJ&
Zeng needs to be used. If the amount is less than 30 parts, sufficient waterproofness cannot be obtained, and conversely, if the amount of 6001fIl is too much, the chelate formation of the modified epoxy resin will be insufficient.

Bituminous materials include coal-based materials and petroleum-based materials.
There are some materials that can be used as raw materials, but it is necessary to select them based on properties such as waterproofness, hardness, and cohesive strength.

When coal is carbonized, it is called distillate, which mainly contains aromatic compounds, and coal tar pitch is further classified into soft, medium, and hard pitches depending on the softening point. Hard coal tar pitch, which is a polymer, has the best waterproof properties, but it is brittle, so
In reality, a small amount of coal tar is mixed with coal tar pitch to balance waterproofness and physical properties. :I-
Luthal, which can cause blooming, is essential as a plasticizer for coal tar pitch. Also 1M stone
Powder i coal tar/coal tar pitch mixture, 3
There is so-called swollen charcoal, which is swollen at a high temperature of 00°C or higher, and has the best waterproof properties. This material has a high softening point and excellent caking strength.

The petroleum-based bituminous material used in the present invention is asphalt. Mainly composed of aliphatic polymer substances9
It has superior caking properties and flexibility compared to coal-based bituminous materials, but its waterproof properties are slightly inferior. Therefore, when using asphalts, it is preferable to use them together with a coal-based bituminous material.

Asphalts include Gilt Night, Glance Pitch,
There are natural asphalts such as grahamatite, and petroleum asphalts obtained from petroleum refining residues such as plain asphalt obtained by oxidative polymerization of straight asphalt and straight asphalt at high temperatures.

The bituminous material used in the present invention has a softening point of 50 to 60.
A soft/medium pinch containing 5 to 20% of °C Nocortar T is suitable as it has a good balance of waterproofness and flexibility.

In the case of swelling charcoal, it is preferable to have a softening point of about 60 to 70° C., since it has excellent flexibility despite being hard. Although asphalt improves the flexibility of pitch, it reduces waterproofness, so it is preferable to use it in an amount of 50X or less in the total amount of bituminous material. When using a bituminous substance having a high softening point, such as hard pitch or hard swelling carbon, flexibility can be improved by using a small amount of liquid synthetic rubber as described below.

In order to improve the flexibility of the coating film, a polymer of a compound having at least one conjugated double bond selected from butadiene, chloroprene, neoprene, etc., or a compound having the above-mentioned conjugated double bond ( Q A copolymer of at least lf! and at least one unsaturated compound such as inbutylene, styrene, acrylonitrile, etc., or a liquid synthetic rubber such as polyimbutylene t, mixed with 0 to 50 parts per 100 parts of a modified epoxy resin. Particularly when hard coal tar pitch, hard swollen carbon, etc. are used, it is preferable to use the above-mentioned liquid synthetic rubber in combination.

Liquid synthetic rubber has a large flexibility imparting effect even with a small amount and has good waterproof properties. However, if the weight average molecular weight is less than 200, the paint film tends to produce sticky sounds, and conversely, if it is more than so, ooo, the viscosity of the paint increases, and the modified epoxy resin,
Problems such as decreased miscibility with bituminous substances, stringy sound during spraying, and difficulty in obtaining a smooth coating film? arise. Therefore, the weight average molecular weight of liquid synthetic rubber is 200~
so, o o o, preferably 500~zo, o
oo is suitable.

As a modified epoxy resin having chelate-forming ability, Adeka Resin EPX-880° Adeka Resin EPX-881 (all product names) manufactured by Kadenka Kogyo 1 can be used.

In designing the entire anticorrosive coating, it is important to balance the i-rate forming ability of the modified epoxy resin, waterproofness, physical properties of the coating film, etc., and the present invention was completed by the following method.

In order to impart coating film stripes, coating film hardness, and painting workability,
Extender pigments such as mica, Merck, and barium acid, and if necessary, coloring pigments such as Bengara, anti-sagging agents, anti-settling agents, etc. can be mixed as appropriate.

The anticorrosive paint is composed of the above-mentioned composition, all solvents, such as aromatic solvents such as doluol, kijiroru, solvent naphtha, M
EK%MIBK, ketone solvents such as cyclohexanone,
alcoholic solvents such as n-propyl alcohol, 1so-7'lopyl alcohol, n-butanol, 1ao-7'tylalkol, ester solvents such as 1[ethyl, butyl acetate, ethylene glycol monoacetate, ethylene glycol monomethyl After mixing and dispersing in a disper with at least two selected from cellosolve solvents such as ether acetate, ethylene glycol monoethyl ether acetate, and ethylene glycol motuptyl ether acetate, the mixture is mixed and dispersed using a disper, followed by a three-roll mill, a ball mill,
It can be prepared by kneading it with a dispersion device such as a sand grind mill, and it can be coated by ordinary coating means such as printing, roller coating, air spraying, and airless spraying.

In addition to the interior of steel ships mentioned above, it is also used as an anticorrosion coating for oil storage tanks, onshore plants, the inner surfaces of bridge girders, and other low-grade surfaces of steel structures.

(Effects of the Invention) ■ The polyhydric phenol group having a P-attached hydroxyl group in the modified epoxy resin reacts with rust, forms a chelate, and stabilizes the rust.

■ Adjacent hydroxyl groups in modified epoxy resin? The polyhydric phenol group possessed has reducing properties and also has the effect of converting red rust into stable black rust.

■ Bituminous substances used in combination with modified epoxy tree manure have excellent waterproof properties and will prevent the progression of rust. It completely prevents the penetration of water, salts, oxygen, etc. into the iron surface.

■ If hard bitumen is used, the paint film will become brittle, causing cracks and damage from impact. It becomes easier to receive. By adding a small amount of liquid synthetic rubber, this drawback can be improved and the durability of the coating film can be improved.

(2) Due to the synergistic effect of (1), (2), and (3) above, and appropriately adjusted physical properties of the coating film, long-term corrosion protection is possible even with simple substrate adjustment.

(Example) Examples of the present invention are shown in Table 1, and Comparative Examples are shown in Table 2.

Table-1 Note 1 = 7 Deka Resin E'PX-880 (solid content 35%,
Manufactured by Kadenka Kogyo Co., Ltd.] Note 2 Near Decal Resin EPX-881 (solid content 53%, manufactured by Kadenka Kogyo Co., Ltd.) Note 3: Softening point 50-60°C, tar oil/soft pitch = 1
0/90 Note 4: Softening point 70-80℃, Mer oil/medium pitch = 1
5/85 Note 5: Swelling carbon (manufactured by BO Chemical) Note 6: Straight asphalt Note 7 Double weight average molecular weight 5. OOO Note 8 = Weight average molecular weight 10.000 Note 9 = Cyclohexanone/Ethyl Cellosolve/Doluol = 20/30150 Table-2 Note 7 = Trade name Epicor) 1001 (Shell Chemical Co., Ltd. Ifri Note 8 = Trade name Persamide 115.75 %Kijirol liquid (
Henkel Co., Ltd. (R) is a curing agent for epoxy resins, which is mixed directly into the paint used, and is not mixed during the production of the paint shown in Comparative Example 1 in Table 2.

a9: The performance of each of the compositions of Examples and Comparative Examples prepared using three rolls of product name R-20 (manufactured by Yamama Kokusaku Pulp Co., Ltd.) was evaluated in the following manner.

(1) A polished mild steel plate with a test plate size of 1.6 x 70 x 150 mm is immersed in 3% saline solution and then exposed outdoors for 3 days to develop rust. This process was repeated 2io times to obtain a rusted steel sheet metal.

This rusted steel plate was removed with a disc sundae and SIS
Adjustable to two types of rust removal levels: 5t-3 (careful rust removal level) and 5ISSt-1 (simple rust removal level).

Next, paints with the compositions of Examples and Comparative Examples were applied to the above two types of rust removal test plates with a brush to a dry film thickness of 20G microns, dried indoors for 7 days, and then used as test plates. did.

(2) Evaluation method a: Paint film appearance - Visually judge the degree of blistering, cracking, rusting, etc.

b2 Adhesive -2 + a Cut the goban that reaches the substrate of the spacing p
, peel off the adhesive tape rapidly and count the number of remaining sections.

C: Flexibility - 90 bends around a 1 inch diameter rod;
Inspect for cracks, peeling, etc.

d: Impact resistance - DuPont impact tester, 500 ri xao
cm, 3 (apply impact with an inch punch and check for peeling of the j!! film.

e: Salt water resistance - After being immersed in 3% saline solution at room temperature for 3 months, the appearance and adhesion of the coating film are examined.

f: High humidity resistance After testing for 14 days at -50°C and 95% relative humidity, the appearance and adhesion of the coating film are examined.

Table 3 shows the evaluation results of Examples and Comparative Examples.

Table-3

Claims (5)

[Claims] (1) (A) General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (However, R_1; H or CH_3, R_2; -CH_2- or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ n; 5 to 30) A high molecular weight reaction product (hereinafter referred to as “modified epoxy resin ''); (b) a bituminous substance; and (c) a liquid synthetic rubber. (2) In claim 1, the polyhydric phenol polyhydric alcohol ester having adjacent hydroxyl groups includes ethylene glycol, propylene glycol, butylene glycol, 1,6-hexanediol, glycerin, trimethylolpropane, pentaerythritol, Sorbit, polyhydric alcohol of glucose, catechol-3-carboxylic acid, catechol-4-carboxylic acid, gallic acid, m
- An anticorrosive coating composition characterized in that it is an ester compound of any combination of digallic acid, pyrogallol-4-carboxylic acid, pyrogallol-4,6-dicarboxylic acid, and tannic acid with a polyhydric phenol carboxylic acid. (3) In claim 1, the polynuclear polyhydric phenol having adjacent hydroxyl groups is catechol, catechol-
3 (or 4)-carboxylic acid (or ester thereof), pyrogallol, pyrogallol-4-carboxylic acid (or ester thereof), pyrogallol-4,6-dicarboxylic acid (or ester thereof), 3,4,5 - An anticorrosive paint composition characterized by being a formalin condensate of trioxybenzoic acid (or its ester), tannic acid (or its ester), and urushiol. (4) In claim 1, the bituminous material is
Coal tar pitch, a mixture of coal tar and coal tar pitch, heavy materials obtained from coal such as swollen coal obtained by heat treating coal powder with coal tar or a mixture of coal tar and coal tar pitch, and petroleum. 30 to 600 parts of at least one selected from straight asphalt, blown asphalt obtained by oxidative polymerization of straight asphalt at high temperature, and naturally occurring natural asphalt is mixed with 100 parts of modified epoxy resin. An anticorrosive paint composition characterized by comprising: (5) In claim 1, the liquid synthetic rubber is a single or copolymer of a compound having at least one conjugated double bond selected from butadiene, chloroprene, and neoprene, or the above-mentioned conjugated double bond. At least one compound having a heavy bond, isobutylene, styrene,
A copolymer with at least one unsaturated compound selected from acrylontrile or polyisobutylene,
An anticorrosive coating composition characterized in that it is mixed in 0 to 50 parts with respect to 100 parts of a modified epoxy resin.