JPWO2022210018A5 - - Google Patents

Description

(Examples 2 to 27, 29 to 37, Reference Example 28, Comparative Examples 1 to 10)
Tables 1 and 2 show the blending amounts of each component, and metal-based coating agents of Examples , Reference Examples, and Comparative Examples were prepared in the same manner as in Example 1. The types of each component indicated by symbols in Tables 1 and 2 are shown below.

Using the metal-based coating agents of the above Examples , Reference Examples, and Comparative Examples, cold-rolled steel sheets were coated with a bar coater. The temperature of the base material to be coated was room temperature. After that, baking was performed for 60 seconds at the baking temperature shown in Tables 3 and 4 to prepare test plates of the surface-treated metals of Examples , Reference Examples, and Comparative Examples. The Zn content in the film in Tables 3 and 4 is a numerical value showing the content of zinc in terms of zinc atoms in the film in g/m2, which is the mass per unit area. In Example 24, the substrate temperature was set to 350° C. and the coating was performed by an airless spray.

[Repellency evaluation]
Repellency evaluation was performed using the metal-based coating agents of Examples , Reference Examples, and Comparative Examples obtained as described above. The evaluation was carried out by applying the metal-based coating agents of each example , reference example, and comparative example to cold-rolled steel sheets heated to 350°C by airless spraying so that the zinc content in the film was 8 g/ ^m2 in terms of zinc atoms. Then, the presence or absence of cissing (a state in which droplets of the metallic coating agent applied due to the Leidenfrost phenomenon touch the substrate surface only intermittently and do not adhere) was visually observed. Evaluation was performed according to the following criteria, and 2 was regarded as a pass. Tables 3 and 4 show the results.
2: Repelling of the metallic coating agent is not visually observed 1: Repelling of the metallic coating agent is visually observed

[Adhesion evaluation]
Adhesion was evaluated using the surface-treated metal test plates of each of the examples , reference examples, and comparative examples obtained above. Evaluation was carried out by a tape peeling test according to JIS K 5600 5-6. Evaluation was performed according to the following criteria, and 2 or more was regarded as a pass. Tables 3 and 4 show the results.
3: No peeling 2: No peeling from the interface between the substrate and the coating 1: Peeling from the interface between the substrate and the coating

[Corrosion resistance evaluation]
A combined cycle test (CCT) defined in JIS H 8502 was performed for 30 cycles using the surface-treated metal test plates of each of the examples , reference examples, and comparative examples obtained above. After that, evaluation was performed according to the following criteria, and 3 or more was regarded as a pass. Tables 3 and 4 show the results.
4: No red rust is observed after 30 CCT cycles 3: 15 or more CCT cycles and less than 30 CCT cycles until red rust occurs 2: 9 or more CCT cycles and less than 15 CCT cycles until red rust occurs 1: Less than 9 CCT cycles until red rust occurs

[Burning]
The scorching property was evaluated by the following method. The metal-based coating agents of each example , reference example, and comparative example were applied with a bar coater (No. 28) using a cold-rolled steel sheet at room temperature as an object to be coated, and baked by heating at 350 ° C. for 60 seconds. rice field. The state of the film at that time was visually observed and evaluated based on the following criteria. Evaluation 2 was set as the pass. Tables 3 and 4 show the results.
2: No burning 1: Burning

Claims (6)

Zinc particles (A), Al particles (B) that are at least one of aluminum particles and aluminum compound particles, a silane coupling agent (C), a solvent (D), and water (E) It is a metal-based coating agent,
(A) + (B), which is the sum of the zinc particles (A) and the Al particles (B), is 10 to 51% by mass with respect to the total mass of the metal-based coating agent,
(A)/(B), which is the mass ratio of the zinc particles (A) to the Al particles (B), is 0.9 to 9.0;
(C) / ((A) + (B)), which is the ratio of the silane coupling agent (C) to the (A) + (B), is 10 to 50% by mass,
The solvent (D) has a volume expansion coefficient of 500 times or less from liquid to gas,
(D)/((D)+(E)), which is the ratio of the solvent (D) to the total of the solvent (D) and the water (E), is 20 to 80% by mass;
The total content of aqueous resins selected from the group consisting of water-soluble resins, aqueous resin emulsions, cellulosic resins, and polysaccharides is 0.15% by mass or less with respect to the total mass,
The zinc particles (A) are spherical and have an average particle size of 1 to 15 μm.
Metallic coating agent. The metal-based coating agent according to claim 1 , wherein the Al particles (B) contain aluminum particles and aluminum compound particles. The metal-based coating agent according to claim 1 or 2 , wherein the silane coupling agent (C) is a silane coupling agent having an epoxy group. The metal-based coating agent according to any one of claims 1 to 3 , wherein the solvent (D) is at least one of dipropylene glycol, N-methylpyrrolidone, ethylene glycol mono-n-butyl ether, and isopropyl alcohol. . A film is formed on the surface of a metal substrate that is an object to be coated with the metal-based coating agent according to any one of claims 1 to 4 ,
The surface-treated metal, wherein the content of zinc in the coating is 4 g/m ² or more in terms of zinc atoms. A surface treatment method comprising a coating step of coating the surface of an object to be coated with the metallic coating agent according to any one of claims 1 to 4 , and a baking step.