US4072795A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thin film electrostatic epoxy powder coating process and the resulting article
Assignee: Westinghouse Electric Corp
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Filing: 1976-10-04
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Granted: 1978-02-07
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Expires: 1996-10-04
Abstract
Abstract A coating powder is made by preparing a composition of two different diglycidyl ethers of bisphenol A and a curing agent, extruding the composition, cooling it to form a solid, and grinding the solid into a powder. Wire or other articles are coated with the coating powder in an electrostatic fluidized bed or with an electrostatic gun and the powder is cured.
Inventors
- 👤 Charles M. Noonan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:15
CPC Classifications
B; B05; B05D; B05D1/00; B05D1/02; B05D1/04; B05D1/06; B05D1/18; B05D1/22; B05D1/24; B05D7/00; B05D7/20; C; C08; C08G; C08G59/00; C08G59/18; C08G59/182; C08G59/186; C08G59/20; C08G59/22; C08G59/226; C08G59/40; C08G59/4007; C08G59/4014; C08G59/4021; C08G59/4035; C08G59/42; C08G59/4207; C09; C09D; C09D163/00; B05D2202/00; B05D2401/00; B05D2401/30; B05D2401/32; Y; Y10; Y10S; Y10S524/00; Y10S524/901; Y10S524/902; Y10S524/904; Y10S525/00; Y10S525/934; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/294; Y10T428/31504; Y10T428/31511; Y10T428/31529
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
290 words
A method of coating a metallic object with a coating powder comprising: (I) applying a coating powder to said metallic object with an electrostatic means selected from the group consisting of a gun and a fluidized bed, said coating powder being made by (A) dry mixing a composition which comprises: (1) a first diglycidyl ether of bisphenol A having an E.E.W. of about 400 to about 900 and a melting point of about 70° to about 110° C; (2) a second diglycidyl ether of bisphenol A having an E.E.W. of about 750 to about 1400 and a melting point of about 100° to about 130° C, where said second diglycidyl ether is different from said first diglycidyl ether and the weight ratio of said first diglycidyl ether to said second diglycidyl ether is about 1 to 1 to about 12 to 1; (3) about 10 to about 60% by weight based on the weight of the total composition of an epoxy ester, the epoxy portion of said ester being derived from a diglycidyl ether of bisphenol A having an E.E.W. of about 400 to about 900 and a melting point of about 70° to about 110° C, and the ester portion being derived from a dibasic acid having the formula HOOC--(CH 2 ) m -- COOH, where m is about 18 to about 54; and (4) about 2 to about 8 phr of a curing agent for said diglycidyl ethers; (B) extruding said composition; (C) cooling said composition to form a solid; and (D) grinding said composition into a powder having a particle size of about 15 to about 74 microns; (II) curing said coating powder at about 125° to about 200° C for about 1 to about 10 minutes.
Claim 2
Independent Claim
290 words
A method of coating a metallic object with a coating powder comprising: (I) applying a coating powder to said metallic object with an electrostatic means selected from the group consisting of a gun and a fluidized bed, said coating powder being made by (A) dry mixing a composition which comprises: (1) a first diglycidyl ether of bisphenol A having an E.E.W. of about 400 to about 900 and a melting point of about 70° to about 110° C; (2) a second diglycidyl ether of bisphenol A having an E.E.W. of about 750 to about 1400 and a melting point of about 100° to about 130° C, where said second diglycidyl ether is different from said first diglycidyl ether and the weight ratio of said first diglycidyl ether to said second diglycidyl ether is about 1 to 1 to about 12 to 1; (3) about 10 to about 60% by weight based on the weight of the total composition of an epoxy ester, the epoxy portion of said ester being derived from a diglycidyl ether of bisphenol A having an E.E.W. of about 400 to about 900 and a melting point of about 70° to about 110° C, and the ester portion being derived from a dibasic acid having the formula HOOC--(CH 2 ) m -- COOH, where m is about 18 to about 54; and (4) about 2 to about 8 phr of a curing agent for said diglycidyl ethers; (B) extruding said composition; (C) cooling said composition to form a solid; and (D) grinding said composition into a powder having a particle size of about 15 to about 74 microns; (II) curing said coating powder at about 125° to about 200° C for about 1 to about 10 minutes.
Claim 3
Dependent Claim
187 words
A method according to claim 1 wherein said composition comprises: (1) a first diglycidyl ether of bisphenol A having an E.E.W. of about 700 to about 875 and a melting point of about 85° to about 100° C; (2) a second diglycidyl ether of bisphenol A having an E.E.W. of about 780 to about 825 and a melting point of about 112° to about 120° C, where the weight ratio of said first diglycidyl ether to said second diglycidyl ether is about 3 to 1 to about 5 to 1; (3) about 10 to about 60% by weight based on the weight of the total composition of an epoxy ester, the epoxy portion of said ester being derived from a diglycidyl ether of bisphenol A having an E.E.W. of about 700 to about 875 and a melting point of about 85° to about 100° C, and the ester portion being derived from a dibasic acid having the formula HOOC--(CH 2 ) m --COOH where m is about 18 to about 54; and (4) about 2 to about 5 phr of a curing agent for said diglycidyl ethers.
Claim 4
Dependent Claim
12 words
A method according to claim 1 wherein said curing agent is dicyandiamide.
Claim 5
Dependent Claim
20 words
A method according to claim 1 wherein said extrusion is performed near but above the melting point of said composition.
Claim 6
Dependent Claim
14 words
A method according to claim 1 wherein said extrusion is performed in a kneader.
Claim 7
Dependent Claim
25 words
A method according to claim 1 wherein said composition is ground to a powder having a particle size of about 100 to about 400 mesh.
Claim 8
Dependent Claim
23 words
A method according to claim 1 wherein said composition includes about 2 to about 8 phr of an accelerator for said diglycidyl ethers.
Claim 9
Dependent Claim
34 words
A method according to claim 7 wherein said accelerator is about 2 to about 5 phr of a mixture of about 20 to about 30% 2-methyl imidazole and about 70 to about 80% dicyandiamide.
Claim 10
Dependent Claim
20 words
A method according to claim 7 wherein said composition includes about 10 to about 30% of a flow control agent.
Claim 11
Dependent Claim
11 words
A method according to claim 1 wherein m is about 36.
Claim 12
Dependent Claim
19 words
A method according to claim 1 wherein the amount of said epoxy ester is about 40 to about 60%.
Claim 13
Dependent Claim
13 words
A method according to claim 1, wherein said metallic object is a wire.
Claim 14
Dependent Claim
10 words
A coated wire made by the method of claim 12.
Claim 15
Dependent Claim
21 words
A coated wire according to claim 13 wherein the coating on said wire is about 1 to about 16 mils thick.
Claim 16
Dependent Claim
39 words
A coated wire made according to the method of claim 12 wherein said wire is about 10 to about 200 mils round, square or rectangular of copper, aluminum, or steel, and said coating is less than 2 mils thick.
Claim 17
Dependent Claim
252 words
An article comprising a substrate having thereon a coating comprising a cured film less than 2 mils thick of a coating powder made by (A) dry mixing a composition which comprises: (1) a first diglycidyl ether of bisphenol A having an E.E.W. of about 400 to about 900 and a melting point of about 70° to about 110° C; (2) a second diglycidyl ether of bisphenol A having an E.E.W. of about 750 to about 1400 and a melting point of about 100° to about 130° C, where said second diglycidyl ether is different from said first diglycidyl ether and the weight ratio of said first diglycidyl ether to said second diglycidyl ether is about 1 to 1 to about 12 to 1; (3) about 10 to about 60% by weight based on the weight of the total composition of an epoxy ester, the epoxy portion of said ester being derived from a diglycidyl ether of bisphenol A having an E.E.W. of about 400 to about 900 and a melting point of about 70° to about 110° C, and the ester portion being derived from a dibasic acid having the formula HOOC--(CH 2 ) m -- COOH, where m is about 18 to about 54; and (4) about 2 to about 8 phr of a curing agent for said diglycidyl ethers; (B) extruding said composition; (C) cooling said composition to form a solid; and (D) grinding said composition into a powder having a particle size of about 15 to about 74 microns.
Claim 18
Dependent Claim
252 words
An article comprising a substrate having thereon a coating comprising a cured film less than 2 mils thick of a coating powder made by (A) dry mixing a composition which comprises: (1) a first diglycidyl ether of bisphenol A having an E.E.W. of about 400 to about 900 and a melting point of about 70° to about 110° C; (2) a second diglycidyl ether of bisphenol A having an E.E.W. of about 750 to about 1400 and a melting point of about 100° to about 130° C, where said second diglycidyl ether is different from said first diglycidyl ether and the weight ratio of said first diglycidyl ether to said second diglycidyl ether is about 1 to 1 to about 12 to 1; (3) about 10 to about 60% by weight based on the weight of the total composition of an epoxy ester, the epoxy portion of said ester being derived from a diglycidyl ether of bisphenol A having an E.E.W. of about 400 to about 900 and a melting point of about 70° to about 110° C, and the ester portion being derived from a dibasic acid having the formula HOOC--(CH 2 ) m -- COOH, where m is about 18 to about 54; and (4) about 2 to about 8 phr of a curing agent for said diglycidyl ethers; (B) extruding said composition; (C) cooling said composition to form a solid; and (D) grinding said composition into a powder having a particle size of about 15 to about 74 microns.
Claim 19
Dependent Claim
187 words
An article according to claim 16 wherein said composition comprises: (1) a first diglycidyl ether of bisphenol A having an E.E.W. of about 700 to about 875 and a melting point of about 85° to about 100° C; (2) a second diglycidyl ether of bisphenol A having an E.E.W. of about 780 to about 825 and a melting point of about 112° to about 120° C, where the weight ratio of said first diglycidyl ether to said second diglycidyl ether is about 3 to 1 to about 5 to 1; (3) about 10 to about 60% by weight based on the weight of the total composition of an epoxy ester, the epoxy portion of said ester being derived from a diglycidyl ether of bisphenol A having an E.E.W. of about 700 to about 875 and a melting point of about 85° to about 100° C, and the ester portion being derived from a dibasic acid having the formula HOOC--(CH 2 ) m --COOH where m is about 18 to about 54; and (4) about 2 to about 5 phr of a curing agent for said diglycidyl ethers.
Claim 20
Dependent Claim
12 words
An article according to claim 16 wherein said curing agent is dicyandiamide.
Claim 21
Dependent Claim
20 words
An article according to claim 16 wherein said extrusion is performed near but above the melting point of said composition.
Claim 22
Dependent Claim
14 words
An article according to claim 16 wherein said extrusion is performed in a kneader.
Claim 23
Dependent Claim
25 words
An article according to claim 16 wherein said composition is ground to a powder having a particle size of about 100 to about 400 mesh.
Claim 24
Dependent Claim
23 words
An article according to claim 16 wherein said composition includes about 2 to about 8 phr of an accelerator for said diglycidyl ethers.
Claim 25
Dependent Claim
34 words
An article according to claim 22 wherein said accelerator is about 2 to about 5 phr of a mixture of about 20 to about 30% 2-methyl imidazole and about 70 to about 80% dicyandiamide.
Claim 26
Dependent Claim
20 words
An article according to claim 22 wherein said composition includes about 10 to about 30% of a flow control agent.
Claim 27
Dependent Claim
11 words
An article according to claim 16 wherein m is about 36.
Claim 28
Dependent Claim
19 words
An article according to claim 16 wherein the amount of said epoxy ester is about 40 to about 60%.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-06 | 1981-08-08 | 1982-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-06 | 1985-08-08 | 1986-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-06 | 1989-08-08 | 1990-02-07 | $7700.00 | Window Closed / Lapsed |