EP 0213567 B1 19900124 - PROCESS FOR APPLYING PHOSPHATE COATINGS
Title (en)
PROCESS FOR APPLYING PHOSPHATE COATINGS
Publication
Application
Priority
US 76943385 A 19850826
Abstract (en)
[origin: US4595424A] Disclosed is an improved method for coating a zinc surface comprising treating said surface with an aqueous, acidic solution containing: (a) about 0.5 to about 4 percent phosphate ion; (b) an ion selected from the group consisting of zinc ions, manganese ions, and mixtures thereof, said ions being present at a level sufficient to form dihydrogen phosphate with substantially all of said phosphate ions; and (c) about 0.01 to about 1 percent complex fluoride ions; wherein the weight:weight ratio of complex fluoride ions:chloride ions in said solution is at a value of about 8:1 or greater. It is preferred that the ratio complex of fluoride ion to chloride ion (F-:Cl-) in said solution to be maintained at a value of greater than about 8:1, preferably greater than about 10:1, and more preferably greater than about 14:1. The select weight:weight complex fluoride:chloride ratio substantially eliminates the abnormal crystal growth frequently found in treated surfaces while at the same time reduces the need for excess fluoride.
IPC 1-7
IPC 8 full level
C23C 22/12 (2006.01); C23C 22/18 (2006.01); C23C 22/36 (2006.01)
CPC (source: EP US)
C23C 22/36 (2013.01 - EP US); C23C 22/362 (2013.01 - EP US)
Designated contracting state (EPC)
AT BE DE FR IT NL SE
DOCDB simple family (publication)
US 4595424 A 19860617; AT E49781 T1 19900215; AU 5871886 A 19870305; AU 594685 B2 19900315; CA 1293165 C 19911217; DE 3628303 A1 19870312; DE 3668475 D1 19900301; EP 0213567 A1 19870311; EP 0213567 B1 19900124; ES 2000229 A6 19880116; GB 2179680 A 19870311; GB 8620633 D0 19861001; JP H06104906 B2 19941221; JP S6247489 A 19870302; MX 165325 B 19921105
DOCDB simple family (application)
US 76943385 A 19850826; AT 86111618 T 19860822; AU 5871886 A 19860613; CA 511358 A 19860611; DE 3628303 A 19860821; DE 3668475 T 19860822; EP 86111618 A 19860822; ES 8601334 A 19860825; GB 8620633 A 19860826; JP 19989186 A 19860826; MX 346586 A 19860818