Abstract: An injection molding method uses a die with a cavity into which molten resin is to be injected to fill the cavity. The die has a shape that causes the molten resin injected into the cavity to branch and merge. The injection molding method includes providing bubbles into the molten resin before the molten resin is injected, generating fine bubbles with the provided bubbles before the molten resin is injected, injecting the molten resin containing the fine bubbles, and bursting the fine bubbles of the injected molten resin containing the fine bubbles in a merging location where the molten resin merges.

Abstract: A method of manufacturing a fiber-reinforced composite material which is molded by impregnating a fiber-reinforced sheet with a resin and curing the resin includes: placing the fiber-reinforced sheet in a cavity of a mold; and molding the fiber-reinforced composite material, the molding including injecting the resin into the cavity of the mold, impregnating the fiber-reinforced sheet with the resin, and curing the resin. In the molding, after fine air bubbles contained in the resin are placed at a predetermined position of the cavity, the resin is cured.

Abstract: In a method for producing a fiber-reinforced composite material, the fiber-reinforced composite material is formed by impregnating a reinforcing fiber sheet with a resin and curing the resin. The method includes: storing the reinforcing fiber sheet in a cavity of a forming mold; and impregnating the reinforcing fiber sheet with the resin by injecting the resin into the cavity of the forming mold, and curing the resin. In the impregnating and curing, the resin containing a magnetic powder is injected into the cavity, and a magnetic field is generated in the cavity to cause the resin containing the magnetic powder to flow.

Abstract: An injection molding method uses a die with a cavity into which molten resin is to be injected to fill the cavity. The die has a shape that causes the molten resin injected into the cavity to branch and merge. The injection molding method includes providing bubbles into the molten resin before the molten resin is injected, generating fine bubbles with the provided bubbles before the molten resin is injected, injecting the molten resin containing the fine bubbles, and bursting the fine bubbles of the injected molten resin containing the fine bubbles in a merging location where the molten resin merges.

Abstract: In a method for producing a fiber-reinforced composite material, the fiber-reinforced composite material is formed by impregnating a reinforcing fiber sheet with a resin and curing the resin. The method includes: storing the reinforcing fiber sheet in a cavity of a forming mold; and impregnating the reinforcing fiber sheet with the resin by injecting the resin into the cavity of the forming mold, and curing the resin. In the impregnating and curing, the resin containing a magnetic powder is injected into the cavity, and a magnetic field is generated in the cavity to cause the resin containing the magnetic powder to flow.

Abstract: A method of manufacturing a fiber-reinforced composite material which is molded by impregnating a fiber-reinforced sheet with a resin and curing the resin includes: placing the fiber-reinforced sheet in a cavity of a mold; and molding the fiber-reinforced composite material, the molding including injecting the resin into the cavity of the mold, impregnating the fiber-reinforced sheet with the resin, and curing the resin. In the molding, after fine air bubbles contained in the resin are placed at a predetermined position of the cavity, the resin is cured.