Patent US4872961A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4872961A Expired / Lapsed US ⏱️ 0.0 years remaining

Corrosion resistant, low temperature cured cathodic electrodeposition coating

Assignee: Dow Chemical Co
•
Filing: 1987-08-28
•
Granted: 1989-10-10
•
Expires: 2007-08-28
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Cathodic electrodepositable coating compositions comprising an aqueous dispersion of (1) at least one cationic epoxy-based resin, (2) at least one blocked isocyanate crosslinker, and (3) a solvent system containing one or more organic solvents are improved by (a) employing a blocked isocyanate crosslinker which deblocks at a temperature of less than about 160° C., and (b) employing as the solvent system, one which is substantially free of any organic solvent which will react with isocyanate groups at the temperature employed to cure said coating.

Inventors

  • 👤 John M. McIntyre
  • 👤 Kenneth W. Anderson
  • 👤 Nancy A. Rao
  • 👤 Richard A. Hickner

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 23:40
CPC Classifications
C; C09; C09D; C09D5/00; C09D5/44; C09D5/4419; C09D5/443; C09D5/4453; B; B01; B01D; B01D39/00; B01D39/14; B01D39/20; B01D39/2055; B01D39/2058; B01D39/2062; C08; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/10; C08G18/28; C08G18/40; C08G18/58; C08G18/581; C08G18/584; C08G18/64; C08G18/6407; C08G18/70; C08G18/72; C08G18/80; C08G18/8061; C08G18/807; C08G18/8077; B01D2239/00; B01D2239/04; B01D2239/0407; B01D2239/0442; B01D2239/06; B01D2239/065; B01D2239/08; B01D2239/086; B01D2239/12; B01D2239/1208; B01D2239/1241; C08G2150/00; C08G2150/90; Y; Y10; Y10S; Y10S524/00; Y10S524/901

Claims Analysis

Total Claims: 50
Claim 1
Independent Claim 87 words
In a cathodic electrodepositable coating composition comprising an aqueous dispersion of (1) at least one cationic epoxy-based resin, (2) at least one blocked isocyanate crosslinker, and (3) a solvent system containing one or more organic solvents: the improvement which comprises (a) employing a blocked isocyanate crosslinker which deblocks at a temperature of less than about 160° C., and (b) employing as the solvent system, one which is substantially free of any organic solvent which will react with isocyanate groups at the temperature employed to cure said coating.
Claim 2
Dependent Claim 87 words
In a cathodic electrodepositable coating composition comprising an aqueous dispersion of (1) at least one cationic epoxy-based resin, (2) at least one blocked isocyanate crosslinker, and (3) a solvent system containing one or more organic solvents: the improvement which comprises (a) employing a blocked isocyanate crosslinker which deblocks at a temperature of less than about 160° C., and (b) employing as the solvent system, one which is substantially free of any organic solvent which will react with isocyanate groups at the temperature employed to cure said coating.
Claim 3
Dependent Claim 65 words
A cathodic electrodepositable coating composition of claim 1 wherein (a) an oxime blocked isocyanate crosslinker which deblocks at a temperature of between about 100° C. and about 155° C. is employed, and (b) said solvent system which is substantially free of any organic solvent which will react with isocyanate groups contains aromatic hydrocarbon(s), aliphatic hydrocarbon(s), glycol ether ester(s), ester(s), ketone(s), ether(s) or any combination thereof.
Claim 4
Dependent Claim 17 words
A cathodic electrodepositable coating composition of claim 2 wherein the blocked isocyanate is a ketoxime blocked isocyanate.
Claim 5
Dependent Claim 76 words
A cathodic electrodepositable coating composition of claim 3 wherein (a) at least a portion of said oxime blocked isocyanate crosslinker is an oxime blocked isocyanate-containing prepolymer wherein said isocyanate-containing prepolymer is the reaction product of a polyisocyanate and a polyether polyol and (b) said solvent system which is substantially free of any organic solvent which will react with isocyanate groups is selected from the group consisting of aromatic hydrocarbon(s), aliphatic hydrocarbon(s), ketone(s) and any combination thereof.
Claim 6
Dependent Claim 83 words
A cathodic electrodepositable coating composition of claim 4 wherein (a) said oxime blocked isocyanate crosslinker is an isocyanate terminated prepolymer prepared from toluene diisocyante and a polyoxypropylene glycol having a number average molecular weight of from about 130 to about 500 which has been blocked with acetone oxime, methyl ethyl ketoxime, cyclohexanone oxime or any combination thereof: and (b) said solvent system which is substantially free of any organic solvent which will react with isocyanate groups contains xylene, cyclohexanone or any combination thereof.
Claim 7
Dependent Claim 46 words
A cathodic electrodepositable coating composition of claim 1, 2, 3, 4 or 5 wherein said epoxy-based resin is based on an advanced epoxy resin prepared by reacting a diglycidyl ether of bisphenol A having an EEW of from about 175 to about 250 with bisphenol A.
Claim 8
Dependent Claim 73 words
A cathodic electrodepositable coating composition of claim 1, 2, 3, 4 or 5 wherein said epoxy-based resin is based on a mixture of an advanced epoxy resin prepared by reacting a diglycidyl ether of bisphenol A having an EEW of from about 175 to about 250 with bisphenol A and an advanced epoxy resin prepared by reacting a diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule with bisphenol A.
Claim 9
Dependent Claim 60 words
A cathodic electrodepositable coating composition of claim 1, 2, 3, 4 or 5 wherein said epoxy resin is based on an advanced epoxy resin prepared by reacting a diglycidyl ether of bisphenol A having an EEW of from about 175 to about 250 and a diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule with bisphenol A.
Claim 10
Dependent Claim 45 words
A cathodic electrodepositable coating composition of claim 7 wherein said epoxy resin is partially capped with a monofunctional phenolic compound in an amount such that up to about 0.7 equivalents of capping agent is employed per epoxy equivalent contained in the epoxy resin before capping.
Claim 11
Dependent Claim 45 words
A cathodic electrodepositable coating composition of claim 8 wherein said epoxy resin is partially capped with a monofunctional phenolic compound in an amount such that up to about 0.7 equivalents of capping agent is employed per epoxy equivalent contained in the epoxy resin before capping.
Claim 12
Dependent Claim 40 words
A cathodic electrodepositable coating composition of claim 7 wherein said diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule is a diglycidyl ether of a polyoxypropylene glycol having an EEW of from about 180 to about 400.
Claim 13
Dependent Claim 40 words
A cathodic electrodepositable coating composition of claim 8 wherein said diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule is a diglycidyl ether of a polyoxypropylene glycol having an EEW of from about 180 to about 400.
Claim 14
Dependent Claim 40 words
A cathodic electrodepositable coating composition of claim 9 wherein said diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule is a diglycidyl ether of a polyoxypropylene glycol having an EEW of from about 180 to about 400.
Claim 15
Dependent Claim 40 words
A cathodic electrodepositable coating composition of claim 10 wherein said diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule is a diglycidyl ether of a polyoxypropylene glycol having an EEW of from about 180 to about 400.
Claim 16
Independent Claim 181 words
A method of coating a composition containing a blocked isocyanate crosslinker, a solvent system containing one or more organic solvents, and a cationic, epoxy resin-based composition onto an object having an electroconductive surface by the steps comprising (1) immersing the electroconductive object into a coating bath comprising an aqueous dispersion of cationic particles of the epoxy resin-based composition, a blocked isocyanate crosslinker and solvent system containing one or more organic solvents; (2) passing an electric current through said bath sufficient to electrodeposit a coating of said composition onto the object by providing a difference in electrical potential between the object and an electrode that is (a) spaced apart from said object; (b) in electrical contact with said bath; and (c) electrically positive in relation to said object; the improvement which comprises employing (a) as the blocked isocyanate crosslinker, a blocked isocyanate crosslinker which deblocks at a temperature below about 160° C., and (b) as the organic solvent system, one which is substantially free of any organic solvent which will react with isocyanate groups at the temperature employed to cure said coating.
Claim 17
Independent Claim 181 words
A method of coating a composition containing a blocked isocyanate crosslinker, a solvent system containing one or more organic solvents, and a cationic, epoxy resin-based composition onto an object having an electroconductive surface by the steps comprising (1) immersing the electroconductive object into a coating bath comprising an aqueous dispersion of cationic particles of the epoxy resin-based composition, a blocked isocyanate crosslinker and solvent system containing one or more organic solvents; (2) passing an electric current through said bath sufficient to electrodeposit a coating of said composition onto the object by providing a difference in electrical potential between the object and an electrode that is (a) spaced apart from said object; (b) in electrical contact with said bath; and (c) electrically positive in relation to said object; the improvement which comprises employing (a) as the blocked isocyanate crosslinker, a blocked isocyanate crosslinker which deblocks at a temperature below about 160° C., and (b) as the organic solvent system, one which is substantially free of any organic solvent which will react with isocyanate groups at the temperature employed to cure said coating.
Claim 18
Dependent Claim 62 words
A method of claim 15 wherein (a) an oxime blocked isocyanate crosslinker which deblocks at a temperature of between about 100° C. and about 155° C. is employed, and (b) said solvent system which is substantially free of any organic solvent which will react with isocyanate groups contains aromatic hydrocarbon(s), aliphatic hydrocarbon(s), glycol ether ester(s), ester(s), ketone(s), ether(s) or any combination thereof.
Claim 19
Dependent Claim 14 words
A method of claim 16 wherein the blocked isocyanate is a ketoxime blocked isocyanate.
Claim 20
Dependent Claim 72 words
A method of claim 17 wherein (a) at least a portion of said oxime blocked isocyanate crosslinker is oxime blocked isocyanate-containing prepolymer wherein said isocyanate-containing prepolymer is the reaction product of a polyisocyanate and a polyether polyol and (b) said solvent system which is substantially free of any organic solvent which will react with isocyanate groups is selected from the group consisting of aromatic hydrocarbon(s), aliphatic hydrocarbon(s), ketone(s) and any combination thereof.
Claim 21
Dependent Claim 80 words
A method of claim 18 wherein (a) said oxime blocked isocyanate crosslinker is an isocyanate terminated prepolymer prepared from toluene diisocyante and a polyoxypropylene glycol having a number average molecular weight of from about 130 to about 500 which has been blocked with acetone oxime, methyl ethyl ketoxime, cyclohexanone oxime or any combination thereof; and (b) said solvent system which is substantially free of any organic solvent which will react with isocyanate groups contains xylene, cyclohexanone or any combination thereof.
Claim 22
Dependent Claim 43 words
A method of claim 15, 16, 17, 18 or 19 wherein said epoxy-based resin is based on an advanced epoxy resin prepared by reacting a diglycidyl ether of bisphenol A having an EEW of from about 175 to about 250 with bisphenol A.
Claim 23
Dependent Claim 70 words
A method of claim 15, 16, 17, 18 or 19 wherein said epoxy-based resin is based on a mixture of an advanced epoxy resin prepared by reacting a diglycidyl ether of bisphenol A having an EEW of from about 175 to about 250 with bisphenol A and an advanced epoxy resin prepared by reacting a diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule with bisphenol A.
Claim 24
Dependent Claim 57 words
A method of claim 15, 16, 17, 18 or 19 wherein said epoxy resin is based on an advanced epoxy resin prepared by reacting a diglycidyl ether of bisphenol A having an EEW of from about 175 to about 250 and a diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule with bisphenol A.
Claim 25
Dependent Claim 42 words
A method of claim 21 wherein said epoxy resin is partially capped with a monofunctional phenolic compound in an amount such that up to about 0.7 equivalents of capping agent is employed per epoxy equivalent contained in the epoxy resin before capping.
Claim 26
Dependent Claim 42 words
A method of claim 22 wherein said epoxy resin is partially capped with a monofunctional phenolic compound in an amount such that up to about 0.7 equivalents of capping agent is employed per epoxy equivalent contained in the epoxy resin before capping.
Claim 27
Dependent Claim 37 words
A method of claim 21 wherein said diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule is a diglycidyl ether of a polyoxypropylene glycol having an EEW of from about 180 to about 400.
Claim 28
Dependent Claim 37 words
A method of claim 22 wherein said diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule is a diglycidyl ether of a polyoxypropylene glycol having an EEW of from about 180 to about 400.
Claim 29
Dependent Claim 37 words
A method of claim 23 wherein said diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule is a diglycidyl ether of a polyoxypropylene glycol having an EEW of from about 180 to about 400.
Claim 30
Dependent Claim 37 words
A method of claim 24 wherein said diglycidyl ether of a compound having two aliphatic hydroxyl groups per molecule is a diglycidyl ether of a polyoxypropylene glycol having an EEW of from about 180 to about 400.
Claim 31
Dependent Claim 21 words
A method of claim 15, 16, 17, 18 or 19 wherein a catalyst is employed to accelerate curing of the coating.
Claim 32
Dependent Claim 16 words
A method of claim 20 wherein a catalyst is employed to accelerate curing of the coating.
Claim 33
Dependent Claim 16 words
A method of claim 21 wherein a catalyst is employed to accelerate curing of the coating.
Claim 34
Dependent Claim 16 words
A method of claim 22 wherein a catalyst is employed to accelerate curing of the coating.
Claim 35
Dependent Claim 16 words
A method of claim 23 wherein a catalyst is employed to accelerate curing of the coating.
Claim 36
Dependent Claim 16 words
A method of claim 24 wherein a catalyst is employed to accelerate curing of the coating.
Claim 37
Dependent Claim 16 words
A method of claim 25 wherein a catalyst is employed to accelerate curing of the coating.
Claim 38
Dependent Claim 16 words
A method of claim 26 wherein a catalyst is employed to accelerate curing of the coating.
Claim 39
Dependent Claim 16 words
A method of claim 27 wherein a catalyst is employed to accelerate curing of the coating.
Claim 40
Dependent Claim 16 words
A method of claim 28 wherein a catalyst is employed to accelerate curing of the coating.
Claim 41
Dependent Claim 25 words
A method of claim 15, 16, 17, 18 or 19 where said coating bath contains from about 60 to about 95 percent water by weight.
Claim 42
Dependent Claim 20 words
A method of claim 20 where said coating bath contains from about 60 to about 95 percent water by weight.
Claim 43
Dependent Claim 20 words
A method of claim 21 where said coating bath contains from about 60 to about 95 percent water by weight.
Claim 44
Dependent Claim 20 words
A method of claim 22 where said coating bath contains from about 60 to about 95 percent water by weight.
Claim 45
Dependent Claim 20 words
A method of claim 23 where said coating bath contains from about 60 to about 95 percent water by weight.
Claim 46
Dependent Claim 20 words
A method of claim 24 where said coating bath contains from about 60 to about 95 percent water by weight.
Claim 47
Dependent Claim 20 words
A method of claim 25 where said coating bath contains from about 60 to about 95 percent water by weight.
Claim 48
Dependent Claim 20 words
A method of claim 26 where said coating bath contains from about 60 to about 95 percent water by weight.
Claim 49
Dependent Claim 20 words
A method of claim 27 where said coating bath contains from about 60 to about 95 percent water by weight.
Claim 50
Dependent Claim 20 words
A method of claim 28 where said coating bath contains from about 60 to about 95 percent water by weight.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-10-09 1993-04-10 1993-10-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-10-09 1997-04-10 1997-10-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-10-09 2001-04-10 2001-10-10 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag