Patent US4921745A successfully refreshed from Google Patents.
US4921745A
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Honeycomb structure of aromatic polyimide
Assignee: Ube Corp
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Filing: 1988-12-27
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Granted: 1990-05-01
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Expires: 2008-12-27
Abstract
Abstract A new honeycomb core structure of heat-resistant aromatic polyimide is disclosed. The structure comprises plural aromatic polyimide sheets wherein adjoining two aromatic polyimide sheets are combined to each other with a heat resistant adhesive at adhesive regions arranged between the two sheets at equal intervals and the adhesive regions on one side of any aromatic polyimide sheet are located at positions shifting from positions of adhesive regions arranged on another side of the sheet. The honeycomb structure is formed by extending the combined aromatic polyimide sheets in the direction vertical to the plane of the polyimide sheets.
Inventors
- 👤 Kazuhiko Mitsui
- 👤 Kazuo Kumamoto
- 👤 Keiichirou Koyashiki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:24
CPC Classifications
B; B32; B32B; B32B3/00; B32B3/10; B32B3/12; B32B27/00; B32B27/34; B32B2305/00; B32B2305/02; B32B2305/024; B32B2379/00; B32B2379/08; B32B2607/00; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1003; Y10T428/00; Y10T428/24; Y10T428/24149; Y10T428/24165; Y10T428/31504; Y10T428/31721
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
106 words
A honeycomb structure of aromatic polyimide comprising plural aromatic polyimide sheets wherein adjoining sheets of an aromatic polyimide prepared from an aromatic tetracarboxylic acid or its derivative and an aromatic diamine are combined to each other with a heat resistant adhesive at adhesive regions arranged between the two sheets at equal intervals and the adhesive regions on one side of any aromatic polyimide sheet are located at positions shifted from positions of adhesive regions arranged on the opposite side of said sheet and wherein the aromatic polyimide sheets are extended in the direction vertical to the plane of the polyimide sheets to form a honeycomb structure.
Claim 2
Dependent Claim
106 words
A honeycomb structure of aromatic polyimide comprising plural aromatic polyimide sheets wherein adjoining sheets of an aromatic polyimide prepared from an aromatic tetracarboxylic acid or its derivative and an aromatic diamine are combined to each other with a heat resistant adhesive at adhesive regions arranged between the two sheets at equal intervals and the adhesive regions on one side of any aromatic polyimide sheet are located at positions shifted from positions of adhesive regions arranged on the opposite side of said sheet and wherein the aromatic polyimide sheets are extended in the direction vertical to the plane of the polyimide sheets to form a honeycomb structure.
Claim 3
Dependent Claim
51 words
The honeycomb structure as claimed in claim 1, wherein said adhesive is an aromatic imide oligomer having an unsaturated group as a terminal group which is obtained by a reaction of an aromatic tetracarboxylic acid, an aromatic diamine and a monoamine compound having an unsaturated group or a monocarboxylic acid compound.
Claim 4
Dependent Claim
116 words
The honeycomb structure as claimed in claim 1, wherein said adhesive is a terminal-modified imide oligomer produced by reacting an aromatic tetracarboxylic acid or its derivative containing at least 50 molar % of 2,3,3',4'-biphenyltetracarboxylic acid or its derivative, a diamine compound, and an unsaturated dicarboxylic acid or its derivative or an unsaturated monoamine in an organic solvent; said oligomer having an unsaturated group as a terminal group and an imide bond within the oligomer; and said oligomer having a logarithmic viscosity of not more than 1.0, said logarithmic viscosity being measured under conditions of a concentration of 0.5 g/100 ml N-methyl-2-pyrrolidone and temperature of 30° C., and has a melting point of 50° to 300° C.
Claim 5
Dependent Claim
144 words
The honeycomb structure as claimed in claim 1, wherein said adhesive is a terminal-modified imide oligomer having been produced by reacting an aromatic tetracarboxylic acid or its derivative containing at least 50 molar % of 3,3',4,4'-biphenyltetracarboxylic acid or its derivative, a diamine compound, and an unsaturated dicarboxylic acid or its derivative or an unsaturated monoamine in an organic solvent; said diamine compound having been selected from the group consisting of trialkylbenzene diamines, bis(phenoxy)benzene diamines, diphenylalkane diamines, bis(phenoxy)propane diamines, bis[(phenoxy)phenyl]propane diamines, diphenylsulfone diamines and bis(phenoxy)diphenylsulfone diamines; said oligomer having an unsaturated group as a terminal group and an imide bond inside of the oligomer; and said oligomer having a logarithmic viscosity of not more than 1.0, said logarithmic viscosity being measured under the conditions of concentration of 0.5 g/100 ml-N-methyl-2-pyrrolidone and temperature of 30° C., and has a melting point of 50° to 300° C.
Claim 6
Dependent Claim
26 words
The honeycomb structure as claimed in claim 1, wherein said aromatic polyimide sheet has a second-order transition temperature in the range of 250° to 400° C.
Claim 7
Dependent Claim
36 words
The honeycomb structure as claimed in claim 1, wherein the aromatic polyimide is a resin which is prepared by reaction of 2,3,3',4'- or 3,3',4,4'-biphenyltetracarboxylic acid, its dianhydride, its ester or its salt with an aromatic diamine.
Claim 8
Dependent Claim
101 words
A process for preparing a honeycomb structure of aromatic polyimide comprising the steps of: preparing a composite of laminated plural aromatic polyimide sheets wherein adjoining aromatic polyimide sheets are combined to each other with a heat-resistant adhesive at adhesive regions arranged between the two sheets at equal intervals and the adhesive regions on one side of any aromatic polyimide sheet are located at positions shifted from positions of adhesive regions arranged on the opposite side of said sheet and extending the combined aromatic polyimide sheets in the direction vertical to the plane of the polyimide sheets to form a honeycomb structure.
Claim 9
Dependent Claim
101 words
A process for preparing a honeycomb structure of aromatic polyimide comprising the steps of: preparing a composite of laminated plural aromatic polyimide sheets wherein adjoining aromatic polyimide sheets are combined to each other with a heat-resistant adhesive at adhesive regions arranged between the two sheets at equal intervals and the adhesive regions on one side of any aromatic polyimide sheet are located at positions shifted from positions of adhesive regions arranged on the opposite side of said sheet and extending the combined aromatic polyimide sheets in the direction vertical to the plane of the polyimide sheets to form a honeycomb structure.
Claim 10
Dependent Claim
55 words
The process for preparing a honeycomb structure as claimed in claim 7, wherein the adhesive is an aromatic imide oligomer having an unsaturated group as a terminal group which is obtained by a reaction of an aromatic tetracarboxylic acid, an aromatic diamine and a monoamine compound having an unsaturated group or a monocarboxylic acid compound.
Claim 11
Dependent Claim
30 words
The process for preparing a honeycomb structure as claimed in claim 7, wherein said aromatic polyimide sheet has a second-order transition temperature in the range of 250° to 400° C.
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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) | 1993-04-30 | 1993-10-30 | 1994-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-30 | 1997-10-30 | 1998-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-30 | 2001-10-30 | 2002-05-01 | $7700.00 | Window Closed / Lapsed |