JPS636591B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Field of Application) The present invention relates to an anticorrosive coating composition used for low-grade surface treatment of steel structures, such as ships, marine structures, plants, bridges, etc., to prevent corrosion. (Prior art) There are bituminous anticorrosive paints for corrosion protection of steel structures, such as two-component coal tar epoxy, coal tar urethane, one-component coal tar chloride rubber, and coal tar vinyl. , these have excellent water resistance, salt water resistance, and corrosion resistance, and are widely used. In particular, two-component coal tar epoxy systems and coal tar urethane systems are popular. (Problem to be solved by the invention) However, in order for these conventional anticorrosive paints to exhibit sufficient performance, careful preparation of the substrate, such as sandblasting SIS Sa-2.5 and power tool treatment SIS St-3, is required. is necessary. Therefore, if the steel structure is large, it may be necessary to erect scaffolding to ensure work safety, and the reality is that the above-mentioned careful preparation of the ground requires a great deal of labor, time, and expense. It is. In addition, two-component anticorrosive paints such as coal tar epoxy and coal tar urethane systems require extra labor to open and mix the can, and are inconvenient in painting work, such as having limited pot life. . An object of the present invention is to provide a one-component anticorrosion paint that can exhibit excellent anticorrosion effects over a long period of time with simple substrate preparation. Another object of the present invention is to provide an anticorrosive paint that can greatly reduce the process of preparing the substrate. (Means for Solving the Problems) The present invention is characterized by the use of butyl recycled rubber and bituminous material as a color vehicle. Another feature of the present invention is that recycled butyl rubber, bituminous material, and chlorinated resin are used as color vehicles. The recycled butyl rubber used as a color vehicle in the present invention is vulcanized butyl rubber used in tire tubes, etc., which has been mechanically and chemically treated to make it dispersible in a solvent. It retains some of the sulfur structure and inherits the properties of vulcanized butyl rubber, and is also thought to undergo oxidation during molecular cleavage to produce active groups such as hydroxyl groups and carboxyl groups. For this reason, in addition to the characteristics of butyl rubber, such as low atmospheric permeability, water resistance, and salt water resistance, it has the property of adsorbing metal ions and exhibits good adhesion due to its affinity with rust, making it suitable for low-grade substrates. It has the excellent properties required for anticorrosive paints. The unique properties of butyl recycled rubber are as follows:
It cannot be obtained with liquid unvulcanized butyl rubber. However, recycled butyl rubber has drawbacks such as poor painting workability, tendency to cause stringing and foaming especially in spray coating, and although the coating film is highly flexible, drying is slow. It is advantageous to use bituminous substances in order to improve the sprayability. However, increasing the amount of bituminous material tends to reduce drying properties. Therefore, in order to improve the hardness and drying properties of the coating film, the present invention uses a chlorinated resin in addition to butyl recycled rubber and a bituminous substance as a color vehicle. As another method for improving spraying workability and drying performance, it is possible to incorporate pigments, but there is a limit as corrosion resistance tends to decrease as the amount incorporated increases. In addition, the proportion of butyl recycled rubber in the color vehicle in the anticorrosive paint composition is 20 to 80% by weight (hereinafter simply referred to as "%").
is displayed. ) is appropriate. This is because if the butyl recycled rubber content is less than 20%, the effect will be small and the purpose of the present invention will not be achieved, and if it is more than 80%, the spraying workability will decrease, which is undesirable, and the most appropriate amount is 30%.
~60%. As mentioned above, the bituminous substance is useful for improving the density of the coating film by improving the spray coating properties, thereby improving the corrosion resistance, and as an agent for improving the compatibility between butyl recycled rubber and chlorinated resin. Addition of a bituminous substance reduces drying properties, so it is preferable to use a chlorinated resin with excellent drying properties and hardness, and a mixture of a bituminous substance and a chlorinated resin is suitable for this anticorrosive coating composition. It is preferable to mix it into the color vehicle of the product in an amount of 80 to 20% by weight, most preferably 70 to 40% by weight. The mixing ratio of bituminous material and chlorinated resin is 80:20 ~
A weight ratio of 30:70 is suitable. If the bituminous material exceeds 80 parts, the drying properties will decrease, and if the chlorinated resin exceeds 70 parts, the coating film will tend to become brittle, and the compatibility with butyl recycled rubber will tend to decrease. The mixing ratio of chlorinated resin and 70:30 to 40:60
Weight ratios are most preferred. The bituminous materials used in the present invention are broadly classified into those made from coal and those made from petroleum. When coal is carbonized, a fraction consisting mainly of aromatic compounds is obtained.The fraction at temperatures between 300 and 360℃ is called coal tar, and the fraction at temperatures above 360℃ is called coal tar pitch.Furthermore, coal tar pitch reaches its softening point. Therefore, it is differentiated into soft, medium, and hard. Hard coal tar pitch, which is a polymer, has excellent waterproof properties, but due to the high viscosity and brittle nature of the solution, it is actually used in combination with coal tar. In addition, there is so-called swollen coal, which is made by swelling coal powder in a mixture of coal tar and coal tar pitch at a high temperature of 300℃ or higher.
It is also the most preferred because it has excellent caking strength considering its high softening point. Petroleum-based bituminous substances include asphalts. It is mainly composed of aliphatic polymeric substances and has excellent cohesive strength and flexibility, but its waterproof properties are slightly inferior to that of coal-based bituminous substances. In the present invention, since butyl recycled rubber has sufficient flexibility, a coal-based bituminous material with excellent waterproof properties is mainly used. As the chlorinated resin used in the present invention, at least one selected from chlorinated rubber, chlorinated polyethylene, and chlorinated polypropylene can be used. The solvents used in the anticorrosive paint composition include mainly hydrocarbon solvents such as toluene and xylene, ketone solvents such as MEK, MIBK, and cyclohexanone, alcohol solvents such as ethanol, isopropyl alcohol, and butyl alcohol, and ethylene glycol. At least two kinds of solvents selected from ethylene glycol solvents such as monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, and acetic esters thereof can be used. As pigments, extender pigments such as talc, barium sulfate, calcium carbonate, silica powder, and mica are mainly used, and commercially available anticorrosive pigments such as zinc chromate and red lead can also be used. Other anti-settling agents and anti-sagging agents that can be used include organic bentonite-based agents, hydrogenated castor oil-based agents, amide-based agents, colloidal silica-based agents, and polyethylene oxide-based agents. When applying this anticorrosive paint, conventional painting means such as brush, roller, and spray painting can be used. In addition, there is no need for careful surface preparation such as SIS St-3, SIS Sa-2.5, etc., which was required for conventional anticorrosive paints, and simple surface preparation, such as SIS St-3, is not necessary.
-1, SIS Sa-1 level, or if the rust is mild, it can be painted by hand brushing or without any treatment, but conventional anti-corrosive paints such as coal tar epoxy paints are applied after careful preparation of the base. It can exhibit corrosion protection that is equivalent to or better than that of other systems. Another advantage in handling the paint is that the anticorrosive paint is one-component, whereas coal tar epoxy paint is two-component. Furthermore, due to the above-mentioned excellent anticorrosive effect of the anticorrosive paint, it is also possible to greatly reduce the great amount of labor, time, and expense required for the conventional careful preparation of the substrate. (Effects of the Invention) (1) Butyl recycled rubber has excellent waterproofness, chemical resistance, and flexibility, and also exhibits excellent adhesion due to its tackiness and affinity for rust. (2) Bituminous substances not only have excellent waterproof properties, but also improve the spray coating workability of the composition, allowing a dense coating film to be obtained, and improving corrosion resistance. (3) Chlorinated resin has excellent hardness and dries quickly, so it improves the fastness and drying properties of the coating film. Due to the synergistic effect of (1), (2), and (3), long-term corrosion protection is possible even with simple substrate preparation, and the substrate cleaning process can be greatly reduced. (Example) Examples of the present invention, comparative examples, and compositions are shown in Attached Table-1.
The evaluation results are shown in Attached Table 2. All of the paints in the examples were prepared using three rolls. A commercially available paint was used for the comparative example. The test plate was a sandblasted board with a size of 1.6 x 70 x 150 mm, which was soaked in 3% saline solution and then exposed outdoors for 3 days to develop rust, which was repeated 10 times. This untreated rust plate is SIS St-1 (simple rust removal level) and SIS St- with a disc sander.
A total of three types of rust removal levels were adjusted: 3 (careful rust removal level). The paints of Examples and Comparative Examples were applied to the above three types of rust removal test plates using an air sprayer to a dry film thickness of 200 microns, and dried at 20°C for 7 days to prepare test pieces. . The test pieces were evaluated in the following manner. (1) Drying property: After drying at 20℃ for 2 days after application,
Evaluate according to JIS-K-5400 coating film curing criteria. (2) Impact resistance: Using a DuPont impact tester, use a 1/2 inch diameter punch to apply an impact of 500g/50cm to determine the degree of peeling of the coating film. (3) Appearance of paint film: Determine the degree of blistering, cracking, rusting, etc. using sunlight. (4) Adhesion: Cut sections reaching the substrate at 2 mm intervals, peel off rapidly with adhesive tape, and count the number of remaining sections. (5) Salt water resistance: After soaking in 3% salt water at room temperature for 3 months, examine impact resistance, adhesion, and coating appearance. (6) High temperature and high humidity resistance: 14 at 50℃ and relative humidity of 95% or higher
After the day-long test, examine impact resistance, adhesion, and appearance of the paint film. The criteria for the evaluation results in Table 2 are as follows. ◎ Good 〇 Fairly good △ Fairly poor × Poor

[Table] Manufactured by Hayakawa Rubber Co., Ltd. Note 2 Triol liquid with solid content of 70% of swelling coal

【table】

Claims (1)

[Scope of Claims] 1. An anticorrosive paint composition using butyl recycled rubber and a bituminous substance as a color vehicle. 2. The anticorrosive coating composition according to claim 1, wherein the bituminous substance is at least one selected from coal tar, coal tar pitch, swelling coal, and asphalt. 3 In claim 1, the mixing ratio of butyl recycled rubber in the color vehicle is 20 to 80% by weight.
An anticorrosive paint composition characterized by: 4. An anticorrosive paint composition using butyl recycled rubber, a bituminous substance, and a chlorinated resin as a color vehicle. 5. The anticorrosive paint composition according to claim 4, wherein the bituminous substance is at least one selected from coal tar, coal tar pitch, swelling coal, and asphalt. 6. The anticorrosive paint composition according to claim 4, wherein the chlorinated resin is chlorinated rubber, chlorinated polyethylene, or chlorinated polypropylene. 7 In claim 4, the mixing ratio of butyl recycled rubber in the vehicle is 20 to 80% by weight.
An anticorrosive paint composition characterized by: 8. The anticorrosive coating composition according to claim 4, characterized in that the mixture ratio of the bituminous substance and chlorinated resin in the vehicle is 80 to 20% by weight. 9. The anticorrosive coating composition according to claim 4, characterized in that the mixing ratio of the bituminous material and the chlorinated resin is 80:20 to 30:70 by weight.