US4145369A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flame-retardant epoxy resin compositions
Assignee: Hitachi Ltd
•
Filing: 1977-09-19
•
Granted: 1979-03-20
•
Expires: 1997-09-19
Abstract
Abstract Flame-retardant epoxy resin compositions comprising a polyepoxide, an acid anhydride curing agent, an imidazole curing accelerator, aluminum trihydrate powder and red phosphorus powder or red phosphorus powder coated by a thermo-setting resin have a lower viscosity and therefore show a longer pot life and better workability on casting as compared with prior art resin compositions. Also, a fly-back transformer coil produced by casting of said flame-retardant epoxy resin compositions is flame-retardant. Even if it burns slightly, no toxic gas is produced. Therefore, the coil has advantages in that a magnet wire is not corroded and voids are difficult to be formed and thereby partial discharge is difficult to occur, resulting in a long life and a stable output voltage.
Inventors
- 👤 Yasuo Hira
- 👤 Ryoichi Sudo
- 👤 Issei Takemoto
- 👤 Tokio Isogai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:07
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/02; C08G; C08G59/00; C08G59/18; C08G59/40; C08G59/42; C08G59/4215; C08G59/68; C08G59/686; C08K3/18; C08K3/20; C08K3/22; C08K3/32; C08K5/00; C08K5/54
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
184 words
A flame-retardant epoxy resin composition comprising 100 parts by weight of a polyepoxide containing more than one epoxy group in its molecule, 0.8 to 1.2 equivalents of an acid anhydride curing agent per equivalent of the polyepoxide, 0.5 to 5 parts by weight of an imidazole curing agent per 100 parts by weight of said polyepoxide, and amounts of aluminum trihydrate powder and at least one member selected from the group consisting of red phosphorus powder and red phosphorus powder coated by a thermo-setting resin within the range surrounded by connecting the points A, B, C, D, E, F, G, H and I as described below per 100 parts by weight of said polyepoxide, wherein the points A, B, C, D, E, F, G, H and I each represent the following compositions: ______________________________________
Red phosphorus
Aluminum powder or red
trihydrate phosphorus powder
powder coated by a thermo-
(parts by setting resin
weight) (parts by weight)
______________________________________
A 72 50
B 83 20
C 103 10
D 160 5
E 220 4
F 198 20
G 178 31
H 154 40
I 112 46
______________________________________
Claim 2
Dependent Claim
184 words
A flame-retardant epoxy resin composition comprising 100 parts by weight of a polyepoxide containing more than one epoxy group in its molecule, 0.8 to 1.2 equivalents of an acid anhydride curing agent per equivalent of the polyepoxide, 0.5 to 5 parts by weight of an imidazole curing agent per 100 parts by weight of said polyepoxide, and amounts of aluminum trihydrate powder and at least one member selected from the group consisting of red phosphorus powder and red phosphorus powder coated by a thermo-setting resin within the range surrounded by connecting the points A, B, C, D, E, F, G, H and I as described below per 100 parts by weight of said polyepoxide, wherein the points A, B, C, D, E, F, G, H and I each represent the following compositions: ______________________________________
Red phosphorus
Aluminum powder or red
trihydrate phosphorus powder
powder coated by a thermo-
(parts by setting resin
weight) (parts by weight)
______________________________________
A 72 50
B 83 20
C 103 10
D 160 5
E 220 4
F 198 20
G 178 31
H 154 40
I 112 46
______________________________________
Claim 3
Dependent Claim
134 words
A flame-retardant epoxy resin composition according to claim 1, wherein said polyepoxide containing more than one epoxy group in its molecule is at least one polyepoxide selected from the group consisting of diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, polyglycidyl esters of polycarboxylic acids and epoxidized cyclohexene derivatives, said acid anhydride curing agent is at least one acid anhydride selected from the group consisting of methyltetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride and modified hexahydrophthalic anhydrides, said imidazole curing accelerator is at least one imidazole compound selected from the group consisting of 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-methylimidazole, 1-benzyl-2-methylimidazole and 1,2-dimethylimidazole, said aluminum trihydrate powder has an average particle size of 1 to 20μ, and said red phosphorus powder or red phosphorus powder coated by a thermo-setting resin has an average particle size of 4 to 20μ.
Claim 4
Dependent Claim
85 words
A flame-retardant epoxy resin composition according to claim 1, wherein said polyepoxide containing more than one epoxy group in its molecule is a mixture of diglycidyl ether of bisphenol A and diglycidyl tetrahydrophthalate, said acid anhydride curing agent is a mixture of methyltetrahydrophthalic anhydride and methylendomethylenetetrahydrophthalic anhydride, said imidazole curing accelerator is 2-ethyl-4-methylimidazole, said aluminum trihydrate powder has an average particle size of 8μ, and said red phosphorus powder or red phosphorus powder coated by a thermo-setting resin has an average particle size of 6μ.
Claim 5
Dependent Claim
35 words
A flame-retardant epoxy resin composition according to claim 1, wherein 0.3 to 2.5 parts by weight of a silane coupling agent is added to 100 parts by weight of a polyepoxide in the resin composition.
Claim 6
Dependent Claim
16 words
A flame-retardant epoxy resin composition according to claim 4, wherein said silane coupling agent is γ-glycidoxypropyltrimethoxysilane.
Claim 7
Dependent Claim
32 words
A flame-retardant epoxy resin composition according to claim 2, wherein 0.3 to 2.5 parts by weight of γ-glycidoxypropyltrimethoxysilane is added to 100 parts by weight of a polyepoxide in the resin composition.
Claim 8
Dependent Claim
32 words
A flame-retardant epoxy resin composition according to claim 3, wherein 0.3 to 2.5 parts by weight of γ-glycidoxypropyltrimethoxysilane is added to 100 parts by weight of a polyepoxide in the resin composition.
Claim 9
Dependent Claim
166 words
A flame-retardant epoxy resin composition comprising 100 parts by weight of a polyepoxide containing more than one epoxy group in its molecule, 0.8 to 1.2 equivalents of an acid anhydride curing agent per equivalent of the polyepoxide, 0.5 to 5 parts by weight of an imidazole curing agent per 100 parts by weight of said polyepoxide, and amounts of aluminum trihydrate powder and red phosphorus powder coated by a thermo-setting resin within the range surrounded by connecting the points A, B, C, D, E, F, G, H and I as described blow per 100 parts by weight of said polyepoxide, wherein the points A, B, C, D, E, F, G, H and I each represent the following compositions: ______________________________________
Aluminum Red phosphorus
trihydrate powder coated
powder by a thermo-
(parts by setting resin
weight) (parts by weight)
______________________________________
A 72 50
B 83 20
C 103 10
D 160 5
E 220 4
F 198 20
G 178 31
H 154 40
I 112 46
______________________________________
Claim 10
Dependent Claim
166 words
A flame-retardant epoxy resin composition comprising 100 parts by weight of a polyepoxide containing more than one epoxy group in its molecule, 0.8 to 1.2 equivalents of an acid anhydride curing agent per equivalent of the polyepoxide, 0.5 to 5 parts by weight of an imidazole curing agent per 100 parts by weight of said polyepoxide, and amounts of aluminum trihydrate powder and red phosphorus powder coated by a thermo-setting resin within the range surrounded by connecting the points A, B, C, D, E, F, G, H and I as described blow per 100 parts by weight of said polyepoxide, wherein the points A, B, C, D, E, F, G, H and I each represent the following compositions: ______________________________________
Aluminum Red phosphorus
trihydrate powder coated
powder by a thermo-
(parts by setting resin
weight) (parts by weight)
______________________________________
A 72 50
B 83 20
C 103 10
D 160 5
E 220 4
F 198 20
G 178 31
H 154 40
I 112 46
______________________________________
Claim 11
Dependent Claim
130 words
A flame-retardant epoxy resin composition according to claim 8, wherein said polyepoxide containing more than one epoxy group in its molecule is at least one polyepoxide selected from the group consisting of diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, polyglycidyl esters of polycarboxylic acids and epoxidized cyclohexene derivatives, said acid anhydride curing agent is at least one acid anhydride selected from the group consisting of methyltetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride and modified hexahydrophthalic anhydrides, said imidazole curing accelerator is at least one imidazole compound selected from the group consisting of 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-methylimidazole, 1-benzyl-2-methylimidazole and 1,2-dimethylimidazole, said aluminum trihydrate powder has an average particle size of 1 to 20μ, and said red phosphorus powder coated by a thermo-setting resin has an average particle size of 4 to 20μ.
Claim 12
Dependent Claim
82 words
A flame-retardant epoxy resin composition according to claim 8, wherein said polyepoxide containing not more than one epoxy group in its molecule is a mixture of diglycidyl ether of bisphenol A and diglycidyl tetrahydrophthalate, said acid anhydride curing agent is a mixture of methyltetrahydrophthalic anhyride and methylendomethylenetetrahydrophthalic anhydride, said imidazole curing accelerator is 2-ethyl-4-methylimidazole, said aluminum trihydrate powder has an average particle size of 8μ, and said red phosphorus powder coated by a thermo-setting resin has an average particle size of 6μ.
Claim 13
Dependent Claim
35 words
A flame-retardant epoxy resin composition according to claim 8, wherein 0.3 to 2.5 parts by weight of a silane coupling agent is added to 100 parts by weight of a polyepoxide in the resin composition.
Claim 14
Dependent Claim
16 words
A flame-retardant epoxy resin composition according to claim 11, wherein said silane coupling agent is γ-glycidoxypropyltrimethoxysilane.
Claim 15
Dependent Claim
32 words
A flame-retardant epoxy resin composition according to claim 9, wherein 0.3 to 2.5 parts by weight of γ-glycidoxypropyltrimethoxysilane is added to 100 parts by weight of a polyepoxide in the resin composition.
Claim 16
Dependent Claim
32 words
A flame-retardant epoxy resin composition according to claim 10, wherein 0.3 to 2.5 parts by weight of γ-glycidoxypropyltrimethoxysilane is added to 100 parts by weight of a polyepoxide in the resin composition.
Claim 17
Dependent Claim
19 words
A flame-retardant epoxy resin composition according to claim 1, wherein said at least one member is red phosphorus powder.
Claim 18
Dependent Claim
125 words
A flame-retardant epoxy resin composition according to claim 15, wherein said polyepoxide containing more than one epoxy group in its molecule is at least one polyepoxide selected from the group consisting of diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, polyglycidyl esters of polycarboxylic acids and epoxidized cyclohexene derivatives, said acid anhydride curing agent is at least one acid anhydride selected from the group consisting of methyltetrahydrophthalic anhydride, methylendomethylene-tetrahydrophthalic anhydride and modified hexahydrophthalic anhydrides, said imidazole curing accelerator is at least one imidazole compound selected from the group consisting of 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-methylimidazole, 1-benzyl-2-methylimidazole and 1,2-dimethylimidazole, said aluminum trihydrate powder has an average particle size of 1 to 20μ, and said red phosphorus powder has an average particle size of 4 to 20μ.
Claim 19
Dependent Claim
76 words
A flame-retardant epoxy resin composition according to claim 15, wherein said polyepoxide containing more than one epoxy group in its molecule is a mixture of diglycidyl ether of bisphenol A and diglycidyl tetrahydrophthalate, said acid anhydride curing agent is a mixture of methyltetrahydrophthalic anhydride and methylendomethylenetetrahydrophthalic anhydride, said imidazole curing accelerator is 2-ethyl-4-methylimidazole, said aluminum trihydrate powder has an average particle size of 8μ, and said red phosphorus powder has an average particle size of 6μ.
Claim 20
Dependent Claim
35 words
A flame-retardant epoxy resin composition according to claim 15, wherein 0.3 to 2.5 parts by weight of a silane coupling agent is added to 100 parts by weight of a polyepoxide in the resin composition.
Claim 21
Dependent Claim
16 words
A flame-retardant epoxy resin composition according to claim 18, wherein said silane coupling agent is γ-glycidoxypropyltrimethoxysilane.
Claim 22
Dependent Claim
32 words
A flame-retardant epoxy resin composition according to claim 16, wherein 0.3 to 2.5 parts by weight of γ-glycidoxypropyltrimethoxysilane is added to 100 parts by weight of a polyepoxide in the resin composition.
Claim 23
Dependent Claim
32 words
A flame-retardant epoxy resin composition according to claim 17, wherein 0.3 to 2.5 parts by weight of γ-glycidoxypropyltrimethoxysilane is added to 100 parts by weight of a polyepoxide in the resin composition.
Claim 24
Dependent Claim
17 words
A flame-retardant epoxy resin composition according to claim 8, wherein the thermosetting resin is a phenol resin.
References Cited (Backward Citations)
US3373135A
Cited
US3477982A
Cited
US3660321A
Cited
US3867344A
Cited
US3563850A
Cited
US3823200A
Cited
US3922459A
Cited
US3780132A
Cited
US3936342A
Cited
US3906055A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-19 | 1982-09-18 | 1983-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-19 | 1986-09-18 | 1987-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-19 | 1990-09-18 | 1991-03-20 | $7700.00 | Window Closed / Lapsed |