Claims
- 1. A temporary rust resisting coating composition having excellent weldability which consists essentially of:
- (A) 10 to 25% by weight of a organic solvent dispersed binder having an ignition loss of not more than 33% by weight,
- (B) 40 to 70% by weight of zinc powder,
- (C) 5 to 50% by weight of an talc, clay or mica which has been heated at not less than 500.degree. C. up to an ignition loss of 3% by weight;
- said binder (A) being a mixture of the solvent type colloidal silica (a.sub.2) and a hydrolyzate (a.sub.1) of the compound having the formula
- (R.sub.1).sub.m Si(OR.sub.2).sub.4-m
- wherein R.sub.1 and R.sub.2, which are the same of different, represent an alkyl group having 1 to 5 carbon atoms, m is 0 or 1 in a weight ratio (a.sub.1 /a.sub.2) of 85/15 to 30/70 based on SiO.sub.2, and said hydrolyzate (a.sub.1) being prepared by controlling a molar ratio of water/OR.sub.2 to from 0.45 to 0.55 and wherein the amounts of the components (A), (B) and (C) are based on a dried film of said coating composition and an amount of water of said coating composition is controlled to not more than 1% by weight.
- 2. The coating composition according to claim 1 wherein said zinc powder has a particle size of 1 to 20 micrometers.
- 3. The coating composition according to claim 1 wherein said zinc powder is an alloy of zinc and other metals.
- 4. The coating composition according to claim 1 wherein said inorganic oxide pigment is clay, talc or mica.
- 5. The coating composition according to claim 1 wherein said inorganic oxide pigment has a particle size of not more than 20 micrometers.
- 6. The coating composition according to claim 1 wherein said dried film has an ignition loss, at the deoxygenated condition for 1 hour, of not more than 8%.
- 7. The coating composition according to claim 1 which exhibits rust resistance and improved weldability at temperatures of 600.degree. C. and above.
- 8. The coating composition according to claim 7 which exhibits rust resistance and improved weldability at temperatures of 600.degree. C. to 800.degree. C.
Priority Claims (1)
Number |
Date |
Country |
Kind |
63-79232 |
Mar 1988 |
JPX |
|
Parent Case Info
This application is a continuation-in-part of Ser. No. 07/653,156, filed Feb. 11, 1992, which in turn is a continuation of Ser. No. 07/331,380, filed Mar. 31, 1989, both of the latter applications being now abandoned.
US Referenced Citations (12)
Foreign Referenced Citations (2)
Number |
Date |
Country |
10141381 |
May 1985 |
EPX |
A30196835 |
Oct 1986 |
EPX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
331380 |
Mar 1989 |
|
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
653156 |
Feb 1991 |
|