Thermoplastic prepreg and laminate
A prepreg formed from a resin and unidirectionally aligned reinforcement fibers, characterized in that: the prepreg is sheet-shaped; the prepreg has cutouts of a depth for cutting the reinforcement fibers, and includes reinforcement fibers (A) cut by the cutouts to a length of 10 to 50 mm and reinforcement fibers (B) having a length of equal to or more than 50% of the sheet length of the prepreg in the alignment direction of the reinforcement fibers; the surface area of a band section including the reinforcement fibers (B) in a plan view is 1.4% to 35.0% of the entire surface area of the prepreg in a plan view; and at least one end of the reinforcement fibers (B) is positioned at an end portion of the prepreg in the alignment direction of the reinforcement fibers.
1. A prepreg comprising a resin and unidirectionally aligned reinforcement fibers,
wherein
the prepreg is sheet-shaped;
the prepreg has slits with a depth capable of cutting off the reinforcement fibers;
the reinforcement fibers of the prepreg comprise reinforcement fibers A cut by the slits to a length of 10 to 50 mm; and reinforcement fibers B having a length equivalent to 50% or more of the sheet length of the prepreg in the alignment direction of the reinforcement fibers;
the surface area in a plan view of a band section containing the reinforcement fibers B is from 1.4% to 35.0% relative to the total surface in a plan view of the prepreg,
at least one end of the reinforcement fibers B is positioned at an edge of the prepreg in the alignment direction of the reinforcement fibers, and
at least two band sections formed from the reinforcement fibers A cut by the slits and band sections containing the reinforcement fibers B are alternately arranged in a repeating pattern over the entire surface of the prepreg, and
the prepeg comprises at least one band section containing the reinforcement fibers B between two band sections formed from the reinforcement fibers A cut by the slits.
2. The prepreg according to claim 1 , wherein a band section containing the reinforcement fibers B is disposed between one band section formed from the reinforcement fibers A cut by the slits and another band section formed from the reinforcement fibers A cut by the slits.
3. The prepreg according to claim 1 , wherein a width Wn of a band section containing the reinforcement fibers B is from 0.5 mm to 10.0 mm, and a distance Wp between one band section containing the reinforcement fibers B and another band section containing the reinforcement fibers B, is from 5 mm to 150 mm.
4. The prepreg according to claim 1 , wherein widths Wn of the band sections containing the reinforcement fibers B are all of the same length.
5. The prepreg according to claim 1 , wherein the reinforcement fibers B are reinforcement fibers that are not cut over the length from one side to the other side of the prepreg.
6. The prepreg according to claim 1 , wherein one side of the prepreg is parallel to the alignment direction of the reinforcement fibers.
7. The prepreg according to claim 1 , wherein the sum total of the cutting lengths formed by the slits in a surface area in a plan view of 1 m 2 of the prepreg, is from 20 m to 150 m.
8. The prepreg according to claim 1 , wherein an angle formed by the slits and the reinforcement fibers is from 30° to 60°.
9. The prepreg according to claim 1 , wherein a thickness of the prepreg is from 50 μm to 200 μm.
10. The prepreg according to claim 1 , wherein the reinforcement fibers are carbon fibers.
11. The prepreg according to claim 1 , wherein the resin that forms the prepreg is a thermoplastic resin.
12. The prepreg according to claim 1 , wherein at least one side of the prepreg is from 500 mm to 2000 mm in length.
13. A laminated base material formed by laminating plural sheets of prepregs, wherein the laminated base material comprises at least one sheet of the prepreg according to claim 1 .
14. The laminated base material according to claim 13 , further comprising at least one layer which is formed from a thermoplastic resin and does not contain the reinforcement fibers.
15. The laminated base material according to claim 13 , wherein a volume fraction of the reinforcement fibers included in the laminated base material is from 15% by volume to 55% by volume relative to the total volume of the laminated base material.
16. A molded article obtained by molding the laminated base material according to claim 13 by a process comprising heating and pressurization.