US4740343A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing rigid resin molds
Assignee: Mitsubishi Gas Chemical Co Inc
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Filing: 1987-03-25
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Granted: 1988-04-26
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Expires: 2007-03-25
Abstract
Abstract A method for producing a rigid resin mold for preparing plastic moldings which comprises: (1) preparing a composition (I) consisting essentially of (A) a cyanate ester resin composition, and (B-1) a metallic substance which does not substantially accelerate gelation of the cyanate ester resin composition (A), (2) preparing a composition (II) consisting essentially of (C) epoxy resin, and (B-2) a metallic substance which accelerates gelation of the cyanate ester resin composition (A) and does not substantially accelerate gelation of the epoxy resin (C) at temperatures below or equal to 100° C., (3) mixing composition (I) of step (1) and composition (II) of step (2) to form composition (III), (4) casting composition (III) of step (3) into a mold (5) and gelling the cast resin.
Inventors
- 👤 Morio Gaku
- 👤 Hidenori Kimbara
- 👤 Jun Yokoi
- 👤 Yasunari Osaki
- 👤 Mitsuru Nozaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:31
CPC Classifications
C; C08; C08L; C08L79/00; C08L79/04; C08L79/08; B; B29; B29C; B29C33/00; B29C33/38; B29C33/40; C08K; C08K3/00; C08K3/02; C08K3/08; H; H05; H05K; H05K2201/00; H05K2201/09; H05K2201/09009; H05K2201/09118
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
237 words
A method for producing a rigid resin mold for preparing plastic moldings which comprises: (1) a step of preparing a composition (I) consisting essentially of (A) 25-75 parts by weight of a cyanate ester resin composition which having a melting point of less than 100° C., and (B-1) 75-25 parts by weight of a metallic substance which does not substantially accelerate gelation of the cyanate ester resin composition (A), (2) a step of preparing a composition (II) consisting essentially of (C) 15-75 parts by weight of epoxy resin having a melting point of less than 80° C., and (B-2) 85-25 parts by weight of a metallic substance which accelerates gelation of the cyanate ester resin composition (A) and does not substantially accelerate gelation of the epoxy resin (C) at temperatures below or equal to 100° C., (3) a step of mixing composition (I) of step (1) and composition (II) of step (2), to form a composition (III) having fluidity at a temperature of less than 100° C., (4) a step of casting composition (III) of step (3) into a mold at a temperature of less than 100° C., (5) a step of gelling the cast resin at a temperature of 60°-150° C. to form self-sustaining solid, and (6) a step of withdrawing the gelled resin from the mold and heating it at a temperature of 150°-240° C. which is higher than the gelation temperature of step (5).
Claim 2
Independent Claim
237 words
A method for producing a rigid resin mold for preparing plastic moldings which comprises: (1) a step of preparing a composition (I) consisting essentially of (A) 25-75 parts by weight of a cyanate ester resin composition which having a melting point of less than 100° C., and (B-1) 75-25 parts by weight of a metallic substance which does not substantially accelerate gelation of the cyanate ester resin composition (A), (2) a step of preparing a composition (II) consisting essentially of (C) 15-75 parts by weight of epoxy resin having a melting point of less than 80° C., and (B-2) 85-25 parts by weight of a metallic substance which accelerates gelation of the cyanate ester resin composition (A) and does not substantially accelerate gelation of the epoxy resin (C) at temperatures below or equal to 100° C., (3) a step of mixing composition (I) of step (1) and composition (II) of step (2), to form a composition (III) having fluidity at a temperature of less than 100° C., (4) a step of casting composition (III) of step (3) into a mold at a temperature of less than 100° C., (5) a step of gelling the cast resin at a temperature of 60°-150° C. to form self-sustaining solid, and (6) a step of withdrawing the gelled resin from the mold and heating it at a temperature of 150°-240° C. which is higher than the gelation temperature of step (5).
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein the ratio of Composition (I) and Composition (II) mixed in step (3) is in range of 25:75 to 95:5.
Claim 4
Dependent Claim
49 words
The method of claim 1 wherein the metallic substance (B-1) is selected from the group consisting of aluminum, aluminum alloys, zinc, zinc alloys, stainless steel and mixtures thereof, and the metallic substance (B-2) is selected from the group consisting of copper, copper alloys, iron, iron alloys and mixtures thereof.
Claim 5
Dependent Claim
45 words
The method of claim 1 wherein the composition (II) contains a curing catalyst (D) which accelerates gelation of the cyanate ester resin composition (A) and which does not substantially accelerate gelation of the epoxy resin (C) at a temperature below or equal to 100° C.
Claim 6
Dependent Claim
26 words
The method of claim 4 wherein the curing catalyst (D) is selected from the group consisting of organic metal salts, metal chelate compounds and mixtures thereof.
Claim 7
Dependent Claim
51 words
The method of claim 5 wherein the curing catalyst (D) is selected from the group consisting of zinc naphthenate, lead stearate, lead naphthenate, zinc octoate, tin oleate, tin octoate, dibutyl tin maleate, manganese naphthenate, cobalt naphthenate, iron acetyl acetonate, copper acetyl acetonate, cobalt acetyl acetonate, manganese acetyl acetonate and mixtures thereof.
References Cited (Backward Citations)
US3427689A
Cited
US3674589A
Cited
US3737266A
Cited
US4410666A
Cited
US4499245A
Cited
US4396745A
Cited
US4466936A
Cited
US4645784A
Cited
US4374076A
Cited
US4506053A
Cited
US4533727A
Cited
US4552690A
Cited
DE3423385A1
Cited
US4576768A
Cited
DE3426883A1
Cited
US4554346A
Cited
US4675358A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-04-26 | 1991-10-26 | 1992-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-26 | 1995-10-26 | 1996-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-26 | 1999-10-26 | 2000-04-26 | $7700.00 | Window Closed / Lapsed |