| 摘要 |
A coating powder for producing a high temperature resistant coating has a resin system which comprises (A) between about 50 and about 93 wt % based on total of (A) plus (B) of a silicone resin and (B) between about 7 and about 50 wt % based on total weight of (A) plus (B) of a polyhydroxyl component. The silicone resin (A) of the coating powder has organic substitutents selected from the group consisting of phenyl, methyl, C2 through C6 alkyl and mixtures thereof. The silicone resin has a viscosity of between about 500 and about 10,000 cps at 150 DEG C., a condensable hydroxyl content of between about 2 and about 4.5 wt %, and a glass transition temperature (Tg) of about 55 DEG C. or above. The silicone resin preferably contains about 0.2% or less of organic solvents. The polyhydroxyl component (B) is a polyhydroxyl compound or blends of polyhydroxyl compounds with average hydroxyl equivalent weight of between 100 and 500, containing an average of at least three hydroxyl groups per molecule, and of number average molecular weight between 300 and 20,000. The blend of the silicone resin (A) and polyhydroxyl component (B) should have a combined glass transition temperature (Tg) of at least about 50 DEG C.
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