A method for producing an injection-molded product is provided, where sunflower hulls are processed into sunflower hull fibers at a maximum temperature T.sub.PFmax of less than 200° C. Then an injection-moldable composite material is produced by mixing the sunflower hull fibers with a plastic material at a maximum temperature T.sub.PCmax ofless than 200° C. Next the produced injection-moldable composite material is automatically injection-molded into an injection-molding tool such that a molded composite material is produced. The composite material introduced into the injection-molding tool has a temperature T.sub.IM of more than 200° C. in at least one section of the injection-molding tool. Then the molded composite material is removed such that the injection-molded product is produced. A corresponding injection-molded product and the use of especially prepared sunflower hull fibers as an additive are also provided.

A method for producing an injection-molded product is provided, where sunflower hulls are processed into sunflower hull fibers at a maximum temperature T.sub.PFmax of less than 200° C. Then an injection-moldable composite material is produced by mixing the sunflower hull fibers with a plastic material at a maximum temperature T.sub.PCmax ofless than 200° C. Next the produced injection-moldable composite material is automatically injection-molded into an injection-molding tool such that a molded composite material is produced. The composite material introduced into the injection-molding tool has a temperature T.sub.IM of more than 200° C. in at least one section of the injection-molding tool. Then the molded composite material is removed such that the injection-molded product is produced. A corresponding injection-molded product and the use of especially prepared sunflower hull fibers as an additive are also provided.

Provided is a glass fiber-reinforced resin molded article having high dimension stability and low dielectric characteristics. In the glass fiber-reinforced resin molded article, the fiber diameter D of glass fiber included in the glass fiber-reinforced resin molded article is in the range of 5.0 to 15.0 μm, the dielectric constant Dk at a measurement frequency of 1 GHz of the glass fiber is in the range of 4.0 to 7.0, the linear expansion coefficient C of the glass fiber is in the range of 2.0 to 6.0 ppm/K, the number average fiber length L of the glass fiber is in the range of 150 to 400 μm, and the D, Dk, C, and L satisfy the following formula (1):

57.9≤Dk×C.sup.1/4×L.sup.1/2/D.sup.1/4≤70.6  (1)

An object of the present invention is to provide a sizing agent composition that gives a carbon fiber from which a carbon fiber-reinforced composite material having excellent adhesion between a resin and the carbon fiber and having excellent mechanical properties can be formed. The sizing agent composition of the invention is a sizing agent composition comprising (A) a blocked isocyanate, and (B) a compound containing at least one polar group and at least one unsaturated group per molecule. In the invention, the mixing ratio (mass ratio) of the blocked isocyanate (A) and the compound (B) containing at least one polar group and at least one unsaturated group per molecule (A/B) is preferably 95/5 to 5/95. In the invention, the blocked isocyanate (A) is preferably a compound having an aliphatic skeleton.

A method for producing a prepreg, includes the steps of (1) an opening step of opening glass fiber bundles to form plural glass fiber filaments, and (2) a step of aligning the plural glass fiber filaments formed in the previous opening step, on a thermosetting resin composition-coated surface of a carrier material so as to make the filaments run nearly parallel to each other in one direction thereon to form a prepreg. A method for producing a laminate, includes a step of preparing two or more prepregs formed in the previous step (2), laminating them in such a manner that, in at least one pair of prepregs, the running direction of the plural glass fiber filaments in one prepreg differs from the running direction of the plural glass fiber filaments in the other prepreg, and heating and pressing them.

A method for producing a prepreg, includes the steps of (1) an opening step of opening glass fiber bundles to form plural glass fiber filaments, and (2) a step of aligning the plural glass fiber filaments formed in the previous opening step, on a thermosetting resin composition-coated surface of a carrier material so as to make the filaments run nearly parallel to each other in one direction thereon to form a prepreg. A method for producing a laminate, includes a step of preparing two or more prepregs formed in the previous step (2), laminating them in such a manner that, in at least one pair of prepregs, the running direction of the plural glass fiber filaments in one prepreg differs from the running direction of the plural glass fiber filaments in the other prepreg, and heating and pressing them.

The purpose of the present invention is to provide a fiber-reinforced resin material having minimal directionality of strength as well as excellent productivity, a method and device for manufacturing a fiber-reinforced resin material whereby a molded article is obtained, and a device for inspecting a fiber bundle group. A method for manufacturing a sheet-shaped fiber-reinforced resin material in which a paste (P1) is impregnated between cut fiber bundles (CF), the method for manufacturing a fiber-reinforced resin material including a coating step applying a coating of a paste (P1) on a first sheet (S11) conveyed in a predetermined direction, a cutting step for cutting a long fiber bundle (CF) using a cutter (113A), a scattering step for dispersing the cut fiber bundles (CF) and scattering the cut fiber bundles (CF) on the paste (P1), and an impregnation step for pressing a fiber bundle group (F1) and the paste (P1) on the first sheet (S11) and impregnating the paste (P1) between the fiber bundles (CF).

The purpose of the present invention is to provide a fiber-reinforced resin material having minimal directionality of strength as well as excellent productivity, a method and device for manufacturing a fiber-reinforced resin material whereby a molded article is obtained, and a device for inspecting a fiber bundle group. A method for manufacturing a sheet-shaped fiber-reinforced resin material in which a paste (P1) is impregnated between cut fiber bundles (CF), the method for manufacturing a fiber-reinforced resin material including a coating step applying a coating of a paste (P1) on a first sheet (S11) conveyed in a predetermined direction, a cutting step for cutting a long fiber bundle (CF) using a cutter (113A), a scattering step for dispersing the cut fiber bundles (CF) and scattering the cut fiber bundles (CF) on the paste (P1), and an impregnation step for pressing a fiber bundle group (F1) and the paste (P1) on the first sheet (S11) and impregnating the paste (P1) between the fiber bundles (CF).

The present invention provides an epoxy resin composition containing:

an epoxy resin [A] that is a compound represented by Chemical formula (1) shown below:

##STR00001##

wherein R.sub.1 to R.sub.4 each independently represent one selected from the group consisting of a hydrogen atom, an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, and a halogen atom, and X represents one selected from —CH.sub.2—, —O—, —S—, —CO—, —C(═O)O—, —O—C(═O)—, —NHCO—, —CONH—, and —SO.sub.2—;

a bifunctional epoxy resin [B] having an amine type glycidyl group;

a curing agent [C] containing an aromatic polyamine, and having at least one substituent selected from an aliphatic substituent, an aromatic substituent, and a halogen atom at an ortho position with respect to an amino group; and

a particulate rubber component [D].

A process for forming a mat containing a fiber filler including providing one or more sources of extended length fiber; feeding the one or more sources of extended length fiber simultaneously to an automated cutting machine to produce chopped tow fibers; separating the chopped fiber tow into individual chopped fibers that form a fiber filler; coating the fiber filler with a binder; depositing the fiber filler on a first sheet of thermoplastic; covering the fiber filler with a second sheet of thermoplastic to form a stack; and moving the stack to a treatment chamber to form a fiber mat.