Lubricating coating agent for plastic working and method for producing the same

Patent metadata

Field	Value
Publication number	US-9487732-B2
Application number	US-201314040053-A
Country	US
Kind code	B2
Filing date	Sep 27, 2013
Priority date	Mar 28, 2011
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

To provide a lubricating coating agent for plastic working, containing a non-black solid lubricating material, and a metal material coated with the agent, which enable highly difficult forging that has been conventionally difficult to practically apply to anything except lubricating coating films containing a black solid lubricant typified by molybdenum disulfide. The problems can be achieved by means of a lubricating coating agent for plastic working, which is characterized by containing, at 5 mass % or more in terms of solid content ratio in a coating film, a calcium sulfate hydrate with a particular scale-like crystal shape among calcium sulfate hydrates deposited by reacting a sulfuric acid or a sulfate with a calcium compound in water, and a metal material coated with the agent.

First claim

What is claimed is:

1. A lubricating coating agent for plastic working comprising 6 mass % to 98 mass % in terms of solid content ratio in a coating film, of a calcium sulfate hydrate deposited by reacting a sulfuric acid or a sulfate with a calcium compound in water, which is 1.5 μm or less in thickness of crystal and scale-like shape; and 2 mass % to 94 mass % in terms of the solid content ratio in the coating film, being comprised of a binder component and/or one or more additives.

2. The lubricating coating agent according to claim 1 , wherein the calcium sulfate hydrate has an intensity ratio of (020) plane/(021) plane of 10 or more, said ratio being obtained from an analysis result in an X-ray diffraction method directed to a smooth surface of a crystal aggregation created by dry-solidifying a dispersion of the crystals of the calcium sulfate hydrate in water on a flat surface at a temperature of 80° C. or less.

3. The lubricating coating agent according to claim 1 , having a suspension stability of 15 mm or more, measured as a sedimentation layer height of 50 ml of a 3 mass % dilution in water of the lubricating coating agent upon storage for 24 hours at 40° C. in a 35 mm diameter cylindrical bottle.

4. The lubricating coating agent according to claim 1 , wherein the calcium sulfate hydrate is present at 10 mass % to 90 mass %.

5. The lubricating coating agent according to claim 1 , wherein the calcium sulfate hydrate is present at 60 mass % to 98 mass %.

6. The lubricating coating agent according to claim 1 , comprising no black components and having an L* value of 50 or more in the L*a*b* color specification system according to JIS-Z-8729.

7. A lubricating coating agent for plastic working comprising at 5 mass % to 98 mass % in terms of solid content ratio in a coating film, of calcium sulfate hydrate crystals, produced by reacting a sulfuric acid or a sulfate with a calcium compound in water, said crystals having a scale-like shape and an average thickness of 1.5 micron or less; wherein said crystals comprise surfaces that are at least partially coated with a calcium compound coating having a solubility in water that is less than solubility in water of the calcium sulfate hydrate.

8. The lubricating coating agent according to claim 7 , wherein the calcium compound coating is selected from the group consisting of calcium salts of inorganic acids, calcium salts of organic acids and mixtures thereof.

9. The lubricating coating agent according to claim 8 , wherein a mass ratio of the calcium sulfate hydrate crystal to calcium compound coating is 5 to 2000.

10. The lubricating coating agent according to claim 9 , wherein the calcium compound coating is selected from the group consisting of calcium fluoride, calcium iodate, calcium phosphite, calcium phosphate, calcium monohydrogen phosphate, calcium diphosphate, calcium metaphosphate, calcium carbonate, calcium silicate, calcium metasilicate, calcium tetraborate, calcium tungstate, calcium molybdate, calcium oxalate, calcium stearate, calcium oleate, resins with calcium coordinated on a hydrated group, water-dispersible resin emulsions with calcium coordinated on a hydrated group and mixtures thereof.

11. The lubricating coating agent according to claim 8 , wherein the calcium compound coating is selected from the group consisting of calcium salts of saturated fatty acids having 12 to 20 carbon atoms or calcium salts of unsaturated fatty acids having 12 to 20 carbon atoms and mixtures thereof; and wherein a mass ratio of the calcium sulfate hydrate crystal to fatty acid calcium salt deposited on the surface of the calcium sulfate hydrate crystal is 1-20.

12. A method of making a lubricating coating agent comprising steps of:
a. reacting a mixture of:
i. a sulfuric acid or a sulfate salt; and
ii. a calcium compound selected from calcium hydroxide, calcium carbonate, calcium phosphate, calcium chloride, calcium oxalate, calcium citrate and mixtures thereof;

in liquid water at temperatures of 30 deg. C or less, to thereby produce a dispersion in water of calcium sulfate hydrate crystals; i) and ii) being present in amounts such that concentration of said crystals is 10 wt % or less, with i) being present in excess;
b. agitating the dispersion such that the calcium sulfate hydrate crystals produced have a scale-like shape and 1.5 microns or less average thickness; and
c. neutralizing the dispersion in water of calcium sulfate hydrate crystals;
d. optionally, coating at least a portion of surfaces of the calcium sulfate hydrate crystals with a calcium compound coating having a solubility in water that is less than solubility in water of the calcium sulfate hydrate; and
e. drying, forming a slurry, mixing with a binder component, mixing with additives or combinations thereof.

13. A metal material having a surface coated with a lubricating coating agent made according to claim 12 , said lubricating coating agent being dried upon said surface at temperatures of 190° C. or lower.

14. The metal material according to claim 13 , wherein the lubricating coating agent contains, as a binder component, at least one selected from aqueous inorganic salts, aqueous organic acid salts, and aqueous resins.

15. The metal material according to claim 13 , wherein the lubricating coating agent further comprises at least one lubricating supplemental component selected from oils, soap, waxes, and extreme pressure agents.

Assignees

• Henkel Ag & Co Kgaa

Inventors

• Komiyama Shinobu
• Serita Atsushi
• Ishii Hitoshi
• Mori Kazuhiko

Classifications

• C10M2201/084

  containing sulfur, selenium or tellurium · CPC title

• C10M2207/125

  having hydrocarbon chains of eight up to twenty-nine carbon atoms, i.e. fatty acids · CPC title

• C10M2201/061

  Carbides; Hydrides; Nitrides · CPC title

• C10M2201/085

  Phosphorus oxides, acids or salts · CPC title

• C10M2207/126

  monocarboxylic · CPC title