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Prepregs and method for production thereof

Assignee: Teijin Ltd
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Filing: 1985-08-01
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Granted: 1987-12-22
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Expires: 2005-08-01
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Abstract

Abstract A prepreg obtained by impregnating fibers with an epoxy resin composition by a hot melt method is described, wherein the epoxy resin composition comprises components (A), (B), and (C), wherein (A) is an epoxy resin (B) is a hardening agent composition containing a hydrazide type hardening agent for an epoxy resin, and having a melting point of not higher than 160 DEG C., and (B) further contains at least one compound selected from the group consisting of alcohols and phenols having a melting point of not less than 50 DEG C., (C) is a urea compound represented by the formula <IMAGE> wherein X and Y each represents H, Cl, or OCH3.

Inventors

  • 👤 Yasuhisa Nagata

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 05:49
CPC Classifications
C; C08; C08G; C08G59/00; C08G59/18; C08G59/40; C08G59/4007; C08G59/4014; C08G59/4035; C08G59/68; C08G59/686; C08J; C08J5/00; C08J5/24; C08J5/241; C08J5/243; C08J5/249; C08J2363/00; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2904; Y10T428/2907; Y10T428/2913; Y10T428/2918; Y10T428/2933; Y10T428/2938; Y10T428/2964; Y10T428/30; Y10T442/00; Y10T442/20; Y10T442/2926; Y10T442/2951

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 111 words
A prepreg obtained by impregnating fibers with an epoxy resin composition by a hot melt method, wherein the epoxy resin composition comprises components (A), (B) and (C), wherein (A) is an epoxy resin, (B) is a hardening agent composition consisting of a hydrazide type hardening agent for an epoxy resin, and having a melting point of not higher than 160° C., and (B) further contains at least one compound selected from the group consisting of alcohols and phenols having a melting point of not less than 50° C., and (C) is a urea compound represented by the formula ##STR7## wherein X and Y each represents H, Cl, and OCH 3 .
Claim 2
Dependent Claim 111 words
A prepreg obtained by impregnating fibers with an epoxy resin composition by a hot melt method, wherein the epoxy resin composition comprises components (A), (B) and (C), wherein (A) is an epoxy resin, (B) is a hardening agent composition consisting of a hydrazide type hardening agent for an epoxy resin, and having a melting point of not higher than 160° C., and (B) further contains at least one compound selected from the group consisting of alcohols and phenols having a melting point of not less than 50° C., and (C) is a urea compound represented by the formula ##STR7## wherein X and Y each represents H, Cl, and OCH 3 .
Claim 3
Dependent Claim 41 words
A prepreg as in claim 1, wherein the amounts of the components (B) and (C) are from 5 to 80 parts by weight and from 0.1 to 20 parts by weight, respectively, per 100 parts by weight of the epoxy resin.
Claim 4
Dependent Claim 20 words
A prepreg as in claim 2, wherein the weight ratio of component (B) to (C) is from 0.5/1 to 20/1.
Claim 5
Dependent Claim 31 words
A prepreg as in claim 1, wherein said at least one compound selected from the group consisting of alcohols and phenols has a melting point of not higher than 160° C.
Claim 6
Dependent Claim 41 words
A prepreg as in claim 1, wherein the amount of said at least one compound selected from the group consisting of alcohols and phenols is from 1 to 50 parts by weight per 100 parts by weight of the component (A).
Claim 7
Dependent Claim 40 words
A prepreg as in claim 5, wherein the weight ratio of the amount of the hardening agent to the amount of said at least one compound selected from the group consisting of alcohols and phenols is from 0.1/1 to 10/1.
Claim 8
Dependent Claim 49 words
A prepreg as in claim 1, wherein said epoxy resin is selected from the group consisting of a bisphenol A-type epoxy resin, a phenol/novolak-type epoxy resin, a cresol/novolak-type epoxy resin, a glycidylamine-type epoxy resin, an alicyclic epoxy resin, a urethane-modified epoxy resin, and a brominated bisphenol A-type epoxy resin.
Claim 9
Dependent Claim 33 words
A prepreg as in claim 1, wherein said hardening agent composition contains a hydrazide compound having a melting point of not higher than 160° C. as the hardening agent for the epoxy resin.
Claim 10
Dependent Claim 34 words
A prepreg as in claim 8, wherein said hydrazide compound is selected from the group consisting of ##STR8## wherein X represents the phenylene group ##STR9## wherein R is H or CH 3 , ##STR10##
Claim 11
Dependent Claim 32 words
A prepreg as in claim 1, wherein said hardening agent composition contains a hydrazide compound having a melting point of higher than 160° C. as the hardening agent of the epoxy resin.
Claim 12
Dependent Claim 41 words
A prepreg as in claim 10, wherein the amount of said at least one compound selected from the group consisting of alcohols and phenols is such that the melting point of the hardening agent composition becomes not higher than 160° C.
Claim 13
Dependent Claim 50 words
A prepreg as in claim 11, wherein said hydrazide compound is selected from the group consisting of adipic acid dihydrazide, sebacic acid dihydrazide, diglycolic acid dihydrazide, tartaric acid dihydrazide, isophthalic acid dihydrazide, dodecanoic acid dihydrazide, malonic acid dihydrazide, oxalic acid dihydrazide, succinic acid dihydrazide, malic acid dihydrazide and derivatives thereof.
Claim 14
Dependent Claim 56 words
A prepreg as in claim 1, wherein said at least one compound selected from the group consisting of alcohols and phenols is selected from the group consisting of pyrocatechol and derivatives thereof, resorcinol and derivatives thereof, hydroquinone and derivatives thereof, pyrogallol and derivatives thereof, trimethylolpropane, cyclohexanediol, octanediol, salicyl alcohol, naphtholic derivatives, dimethylhexanetriol, tetritol, and stearyl alcohol.
Claim 15
Dependent Claim 21 words
A prepreg as in claim 1, wherein said urea compound is selected from the group consisting of 3-(3,4-dichlorophenyl)-1,1-dimethylurea, 3-(p-chlorophenyl)-1,1-dimethylurea, and 3-(p-methoxyphenyl)-1,1-dimethylurea.
Claim 16
Dependent Claim 22 words
A prepreg as in claim 1, wherein the viscosity of said epoxy resin is from 10 to 2,000 poises at 70° C.
Claim 17
Dependent Claim 28 words
A prepreg as in claim 1, wherein said fibers are selected from the group consisting of carbon fibers, glass fibers, silicon carbide fibers, alumina fibers, and metal fibers.
Claim 18
Dependent Claim 29 words
A prepreg as in claim 1, wherein said fibers are in a form of milled fibers, chopped fibers, unidirectional fiber bundles, woven fabrics, knitted fabrics, felts, or nonwoven fabrics.
Claim 19
Dependent Claim 20 words
A prepreg as in claim 1, wherein said phenol is capable of dissolving the hardening agent when said phenol melts.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-12-21 1991-06-22 1991-12-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-12-21 1995-06-22 1995-12-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-12-21 1999-06-22 1999-12-22 $7700.00 Window Closed / Lapsed

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