US 12,404,399 B2
Thermosetting resin sheet and printed wiring board
Eiichiro Saito, Osaka (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Appl. No. 17/914,690
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
PCT Filed Apr. 1, 2021, PCT No. PCT/JP2021/014226
§ 371(c)(1), (2) Date Apr. 21, 2023,
PCT Pub. No. WO2021/201252, PCT Pub. Date Oct. 7, 2021.
Claims priority of application No. 2020-067746 (JP), filed on Apr. 3, 2020.
Prior Publication US 2023/0257576 A1, Aug. 17, 2023
Int. Cl. C08L 63/00 (2006.01); C08J 5/24 (2006.01); H05K 1/03 (2006.01)
CPC C08L 63/00 (2013.01) [C08J 5/244 (2021.05); H05K 1/036 (2013.01); C08J 2363/00 (2013.01); C08J 2463/00 (2013.01); C08L 2205/025 (2013.01); C08L 2205/035 (2013.01); H05K 2201/0195 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A thermosetting resin sheet consisting of:
a prepreg layer including a base member and a semi-cured product of a first thermosetting resin composition impregnated into the base member; and
a resin sheet layer stacked on the prepreg layer, wherein:
the resin sheet layer is a semi-cured product of a second thermosetting resin composition,
each of the first thermosetting resin composition and the second thermosetting resin composition contains a thermosetting resin and an additive selected from the group consisting of a curing agent, a curing accelerator, a flame retardant, and an inorganic filler,
the prepreg layer and the resin sheet layer are in a condition that, a curing time to further cure the resin sheet layer is longer than a curing time to further cure the prepreg layer,
the prepreg layer and the resin sheet layer are in a condition that the semi-cured product of the first thermosetting resin composition in the prepreg layer has been cured in a more advanced degree than the semi-cured product of the second thermosetting resin composition in the resin sheet layer,
the curing time to further cure the resin sheet layer is a time to gelatinize resin powder of the resin sheet layer at a temperature of 170° C. and is measured in compliance with the JIS C6521-1996 standard, and
the curing time to further cure the prepreg layer is a time to gelatinize resin powder of the prepreg layer at a temperature of 170° C. and is measured in compliance with the JIS C6521-1996 standard.