	US 12,448,510 B2
	Prepreg, method for producing same, and slit tape prepreg
Hiroshi Kobayashi, Tacoma, WA (US); Taiki Maeyama, Ehime (JP); and Hiroaki Sakata, Ehime (JP)
Assigned to Toray Industries, Inc., Tokyo (JP)
Filed by Toray Industries, Inc., Tokyo (JP)
Filed on Jun. 6, 2023, as Appl. No. 18/206,386.
Application 18/206,386 is a continuation of application No. 16/475,518, granted, now 11,708,487, previously published as PCT/JP2018/001443, filed on Jan. 18, 2018.
Claims priority of application No. 2017-007304 (JP), filed on Jan. 19, 2017; application No. 2017-007305 (JP), filed on Jan. 19, 2017; and application No. 2017-201581 (JP), filed on Oct. 18, 2017.
Prior Publication US 2023/0357561 A1, Nov. 9, 2023
Int. Cl. C08L 63/00 (2006.01); C08J 5/24 (2006.01)

CPC C08L 63/00 (2013.01) [C08J 5/243 (2021.05); C08J 2363/00 (2013.01); C08J 2363/02 (2013.01); C08J 2463/00 (2013.01); C08J 2463/02 (2013.01); C08J 2481/06 (2013.01); C08L 2205/025 (2013.01); C08L 2205/03 (2013.01); C08L 2205/035 (2013.01)]

13 Claims

1. A prepreg comprising the components [A] to [D] below and a preliminary reaction product of the component [B] and the component [C],

wherein the component [B] comprises a m- or p-aminophenol epoxy resin [b1] and either a glycidyl ether epoxy resin or a glycidyl amine epoxy resin [b2] that has two or more glycidyl groups in a molecule, and the component [b1] in the prepreg including the preliminary reaction product accounts for 10 to 60 parts by mass, whereas the component [b2] in the prepreg including the preliminary reaction product accounts for 40 to 90 parts by mass relative to the total quantity, which accounts for 100 parts by mass, of the component [B] in the prepreg including the preliminary reaction product,

wherein the epoxy resin composition is the remainder of the prepreg deprived of the component [A] and has a degree of conversion of 1% or more and 20% or less and a glass transition temperature in the range of −5° C. to 20° C. as measured by differential scanning calorimetry (DSC), and

wherein at least one surface resin in the prepreg has a storage elastic modulus G′ in the range of 1.0×10³to 2.0×10⁸Pa as measured at a temperature of 40° C. and an angular frequency in the range of 0.06 to 314 rad/s:

[A] carbon fiber,

[B] an epoxy resin,

[C] a curing agent, and

[D] a thermoplastic resin.