US 12,441,853 B2
Prepreg and carbon fiber-reinforced composite material
Mizuki Sasaki, Osaka (JP); and Toru Kaneko, Osaka (JP)
Assigned to TEIJIN LIMITED, Osaka (JP)
Appl. No. 16/980,100
Filed by TEIJIN LIMITED, Osaka (JP)
PCT Filed Mar. 12, 2019, PCT No. PCT/JP2019/009986
§ 371(c)(1), (2) Date Sep. 11, 2020,
PCT Pub. No. WO2019/176935, PCT Pub. Date Sep. 19, 2019.
Claims priority of application No. 2018-046085 (JP), filed on Mar. 13, 2018.
Prior Publication US 2021/0024713 A1, Jan. 28, 2021
Int. Cl. C08J 5/04 (2006.01); C08J 5/24 (2006.01); C08K 5/18 (2006.01); C08K 5/21 (2006.01)
CPC C08J 5/042 (2013.01) [C08J 5/243 (2021.05); C08J 5/249 (2021.05); C08K 5/18 (2013.01); C08J 2363/00 (2013.01); C08K 5/21 (2013.01)] 13 Claims
 
1. A prepreg comprising:
a fiber-reinforced substrate composed of a carbon fiber;
an epoxy resin composition with which the fiber-reinforced substrate is partially or wholly impregnated,
wherein a gel time of the epoxy resin composition at 150° C. is 300 seconds or less, and
wherein the epoxy resin composition includes an epoxy resin, a dicyandiamide, a urea-based accelerator and an aromatic amine represented by the following Formula (1),

OG Complex Work Unit Chemistry
wherein the aromatic amine has at least one substituent other than a hydrogen atom in an ortho position with respect to an amino group, and, in Chemical Formula (1), R1 to R8 each independently represent any of a hydrogen atom, an aliphatic substituent having 1 to 6 carbon atoms, an aromatic substituent, and a halogen atom, at least one of the substituents is the aliphatic substituent having 1 to 6 carbon atoms, and X represents any of —CH2—, —CH(CH3)—, —C(CH3)2—, —S—, —O—, —CO—, —CONH—, and —C(═O)—, and
wherein the blending amount of the aromatic amine is from 3 to 20 parts by mass with respect to 100 parts by mass of the total epoxy resin,
the blending amount of the dicyandiamide is from 1 to 4 parts by mass with respect to 100 parts by mass of the total epoxy resin, and
the blending amount of the urea-based accelerator is from 3 to 7 parts by mass with respect to 100 parts by mass of the total epoxy resin, and
wherein
an epoxy resin in the epoxy resin composition consists essentially of two or more epoxy resins selected from bisphenol epoxy resins, alcohol epoxy resins, biphenyl epoxy resins, hydrophthalic acid epoxy resins, dimer acid epoxy resins, alicyclic epoxy resins, tetrafunctional epoxy resins having a glycidyl amine structure, naphthalene epoxy resins and novolac epoxy resins, and
the blending amount of the tetrafunctional epoxy resins having a glycidyl amine structure is from 50 to 75 parts by mass with respect to 100 parts by mass of the total epoxy resin.