US4241101A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low dissipation factor epoxy coating powder
Assignee: ABB Inc USA
•
Filing: 1979-05-17
•
Granted: 1980-12-23
•
Expires: 1999-05-17
Abstract
Abstract A coating powder is disclosed which is prepared from a solventless non-aqueous composition of a solid epoxy resin having an epoxy equivalent weight of about 400 to about 8000, a Durran's softening point of at least 70 DEG , a solid polyanhydride curing agent at least about 50 mole % of which is trimellitic anhydride, and a cross-linking agent having the general formula R3SnX where each R is selected from alkyl, aryl, aralkyl, and alkaryl up to C20 and X is selected from acetate, propionate, butyrate, halogen, and hydroxyl. The composition is dry-blended and then melt-mixed at 50 DEG to 150 DEG C. To prepare the coating powder, it is then cooled, crushed, and ground to a particle size of less than 100 microns. The coating powder is electrostatically applied to a conductor and is cured above the melting point of the resin.
Inventors
- 👤 Howard E. Saunders
- 👤 James D. B. Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:30
CPC Classifications
C; C08; C08G; C08G59/00; C08G59/18; C08G59/40; C08G59/42; C08G59/4223; C08G59/68; C09; C09D; C09D163/00; H; H01; H01B; H01B13/00; H01B13/06; H01B13/065; H01B3/00; H01B3/18; H01B3/30; H01B3/40
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
150 words
A solventless, non-aqueous composition which comprises (A) a solid bisphenol A epoxy resin having an EEW of about 400 to about 8000, a Durran's softening point of at least about 70° C., and less than 30 hydroxyl groups per molecule; (B) about 5 to 40 phr of a solid polyanhydride curing agent at least about 50 mole % of which is trimellitic anhydride; (C) about 0.01 to about 1 phr of a cross-linking agent having the general forma R 3 SnX where each R is independently selected from alkyl, aryl, aralkyl, and alkaryl up to C 20 , and X is selected from acetate, propionate, butyrate, halogen, and hydroxy; (D) about 0.01 to about 5 phr of an accelerator for said curing agent; and (E) about 0.1 to about 5 phr of an activator for said cross-linking agent selected from the group consisting of catechol, pyrogallol, phloroglucinol, and mixtures thereof.
Claim 2
Dependent Claim
150 words
A solventless, non-aqueous composition which comprises (A) a solid bisphenol A epoxy resin having an EEW of about 400 to about 8000, a Durran's softening point of at least about 70° C., and less than 30 hydroxyl groups per molecule; (B) about 5 to 40 phr of a solid polyanhydride curing agent at least about 50 mole % of which is trimellitic anhydride; (C) about 0.01 to about 1 phr of a cross-linking agent having the general forma R 3 SnX where each R is independently selected from alkyl, aryl, aralkyl, and alkaryl up to C 20 , and X is selected from acetate, propionate, butyrate, halogen, and hydroxy; (D) about 0.01 to about 5 phr of an accelerator for said curing agent; and (E) about 0.1 to about 5 phr of an activator for said cross-linking agent selected from the group consisting of catechol, pyrogallol, phloroglucinol, and mixtures thereof.
Claim 3
Dependent Claim
39 words
A composition according to claim 1 wherein said epoxy resin has an epoxy equivalent weight of about 750 to about 2000, a Durran's softening point of at least about 90° C., and less than 20 hydroxyl groups per molecule.
Claim 4
Dependent Claim
18 words
A composition according to claim 1 wherein said solid polyanhydride curing agent is 100 mole % trimellitic anhydride.
Claim 5
Dependent Claim
16 words
A composition according to claim 1 wherein said accelerator for said curing agent is 2-methyl imidazole.
Claim 6
Dependent Claim
18 words
A composition according to claim 1 wherein R is C 4 to C 10 and X is acetate.
Claim 7
Dependent Claim
14 words
A composition according to claim 1 wherein R 3 SnX is tributyl tin acetate.
Claim 8
Dependent Claim
15 words
A composition according to claim 1 wherein said activator for said cross-linking agent is catechol.
Claim 9
Dependent Claim
19 words
A composition according to claim 1 which includes about 0.2 to about 5 phr of a flow control agent.
Claim 10
Dependent Claim
13 words
A composition according to claim 8 wherein said flow agent is a polyacrylate.
Claim 11
Dependent Claim
18 words
A composition according to claim 1 which includes up to about 40 phr of a pigment or dye.
Claim 12
Dependent Claim
17 words
A composition according to claim 1 which includes 0.005 to about 5 phr of a thixotropic agent.
Claim 13
Dependent Claim
12 words
A composition according to claim 11 wherein said thixotropic agent is silica.
Claim 14
Dependent Claim
48 words
A method of preparing an electrostatic powder coating composition comprising dry blending a composition according to claim 1, melt mixing said composition at about 50° to about 150° C., cooling said composition, crushing said composition, and grinding said composition to a particle size of less than 100 microns.
Claim 15
Dependent Claim
12 words
An electrostatic coating composition prepared according to the method of claim 13.
Claim 16
Dependent Claim
32 words
A method of forming a coating on a conductor comprising electrostatically applying the electrostatic coating composition of claim 13 to a conductor and fusing and curing said composition above its melting point.
Claim 17
Dependent Claim
144 words
A solventless, non-aqueous composition which comprises (A) a solid bisphenol A epoxy resin having an epoxy equivalent weight of about 750 to about 2000, a Durran's softening point of at least about 90° C., and less than 20 hydroxyl groups per molecule, (B) about 2.5 to about 20 phr of trimellitic anhydride, (C) about 0.05 to about 2 phr of 2-methyl imidazole, (D) about 0.02 to about 0.5 phr of a cross-linking agent having the general formula R 3 Sn--OCOCH 3 where each R is independently selected from alkyl, aryl, arykyl and alkaryl from C4 to C10, (E) about 0.2 to about 2 phr of catechol, (F) about 0.5 to about 3 phr of a polyacrylate flow control agent, (G) about 5 to about 20 phr of a pigment or a dye, (H) about 0.01 to about 2 phr of a silica thixotropic agent.
Claim 18
Dependent Claim
144 words
A solventless, non-aqueous composition which comprises (A) a solid bisphenol A epoxy resin having an epoxy equivalent weight of about 750 to about 2000, a Durran's softening point of at least about 90° C., and less than 20 hydroxyl groups per molecule, (B) about 2.5 to about 20 phr of trimellitic anhydride, (C) about 0.05 to about 2 phr of 2-methyl imidazole, (D) about 0.02 to about 0.5 phr of a cross-linking agent having the general formula R 3 Sn--OCOCH 3 where each R is independently selected from alkyl, aryl, arykyl and alkaryl from C4 to C10, (E) about 0.2 to about 2 phr of catechol, (F) about 0.5 to about 3 phr of a polyacrylate flow control agent, (G) about 5 to about 20 phr of a pigment or a dye, (H) about 0.01 to about 2 phr of a silica thixotropic agent.
References Cited (Backward Citations)
US3400098A
Cited
US3244670A
Cited
US3344096A
Cited
US3506598A
Cited
US3477971A
Cited
US4009223A
Cited
US4040993A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-12-23 | 1984-06-23 | 1984-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-23 | 1988-06-23 | 1988-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-23 | 1992-06-23 | 1992-12-23 | $7700.00 | Window Closed / Lapsed |