Patent US3725345A successfully refreshed from Google Patents.
US3725345A
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Composition comprising an epoxy resin acid anhydride and a n,n{40 {0 bis-imide
Assignee: Rhone Poulenc SA
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Filing: 1971-01-14
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Granted: 1973-04-03
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Expires: 1991-01-14
Abstract
Abstract IN WHICH D represents a divalent radical containing a carboncarbon double bond, and A represents a divalent radical containing at least two carbon atoms. A thermosetting composition which may be cured to give resins having good heat stability and rigidity comprising the reaction product of an epoxy resin, a carboxylic acid anhydride and a N, N''-bis-imide of the formula:
Inventors
- 👤 M Bargain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:43
CPC Classifications
C; C08; C08G; C08G59/00; C08G59/18; C08G59/40; C08G59/44; C08G59/46; C08G59/48; C08G59/4007; C08G59/4014; C08G59/4042
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
26 words
A composition according to claim 1, wherein the ratio of the number of anhydride groups to the number of epoxy groups is from 0.4:1 to 1.5:1.
Claim 2
Dependent Claim
26 words
A composition according to claim 2, wherein the ratio of the number of anhydride groups to the number of epoxy groups is from 0.8:1 to 1.1:1.
Claim 3
Dependent Claim
26 words
A composition according to claim 1, wherein the bis-imide is present in an amount from 40 to 250 percent based on the weight of epoxy resin.
Claim 4
Dependent Claim
26 words
A composition according to claim 4, wherein the bis-imide is present in an amount from 120 to 200 percent based on the weight of epoxy resin.
Claim 5
Dependent Claim
48 words
A composition according to claim 1, wherein the epoxy resin is a glycidyl ether of a polyol or phenol, the reaction product of epichlorohydrin and a primary or secondary amine or an aliphatic or alicyclic polyepoxide obtained by reacting a per-acid with an unsaturated aliphatic or alicyclic compound.
Claim 6
Dependent Claim
18 words
A composition according to claim 1, wherein the epoxy resin contains at least three epoxy groups per molecule.
Claim 7
Dependent Claim
21 words
A composition according to claim 1, wherein the epoxy resin is a glycidyl ether of a poly(hydroxyphenyl)alkane or a phenol/formaldehyde resin.
Claim 8
Dependent Claim
22 words
A composition according to claim 1, wherein the carboxylic acid anhydride is phthalic, maleic, tetrahydrophthalic, hexahydrophthalic, endomethylenetetrahydrophthalic, itaconic, citraconic or dodecylsuccinic anhydride.
Claim 9
Dependent Claim
21 words
A composition according to claim 1, wherein the carboxylic acid anhydride is trimellitic, pyromellitic, azophthalic, benzophenonetetracarboxylic, cyclopentatetracarboxylic, 3,4,4''-benzophenonetricarboxylic or benzoylpyromellitic anhydride.
Claim 10
Dependent Claim
44 words
A composition according to claim 1, wherein A represents a divalent radical comprising Several benzene or alicyclic radicals which are joined directly, or indirectly by an oxygen or sulphur atom, an alkylene group having from one to three carbon atoms, or a -NR2-, -P(O)R1-,
Claim 11
Dependent Claim
16 words
A composition according to claim 1, wherein D is derived from an ethylenic anhydride of formula
Claim 12
Dependent Claim
14 words
A composition according to claim 1, which also contains an epoxy resin curing accelerator.
Claim 13
Dependent Claim
20 words
A cured resin obtained by curing a composition as claimed in claim 1 at a temperature from 150* to 300*C.
References Cited (Backward Citations)
US3379685A
Cited
US3450711A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |