A layer pad (10) comprises a substantially flat sheet (12) having first and second opposite substantially planar faces (14, 16). The layer pad (10) further includes at least one raised formation (18) on at least one of the faces (14, 16).

A cavity plate assembly (400) for a preform mold (100), which includes a cavity plate (410) having an array of seats (412) and a corresponding array of cavity inserts (440) mounted to a front face (CVF) of the cavity plate (410) and in communication with a respective seat (412). Each cavity insert (440) includes a body (441) with a mounting face (441a) and a spigot (443) projecting from the mounting face (441a) and received in a respective seat (412) of the cavity plate (410) such that the mounting (441a) face abuts the front face (CVF) of the cavity plate (410). Each cavity insert (440) also includes a molding surface (448) along its length, at least two thirds of which extends beyond the cavity plate (410).

An injection mold with a centering device includes a die-holding plate with a cavity-forming die unit, a core-holding plate with a core unit, and a stripping plate between the core-holding and die-holding plates. The centering device has a insert and a mount with a clearance, which is rotationally symmetrical about a center axis and is for receiving the insert. The insert has an opening for receiving the core unit and the insert and the clearance of the mount are insertable in a torsion-free manner in the clearance of the mount in at least three positions rotatable about a center axis of the insert, and the center axis of the clearance and the center axis of the insert overlie one another. A center axis of the opening of the insert is arranged eccentrically in relation to the center axis of the insert by an offset. The centering unit is arranged in the stripping plate.

An apparatus for molding process includes a mount including a base, a support on the base, first and second side columns, and a mounting member moveably on tops of the first and second columns; pneumatic first and second half molding assemblies for forming a mold; and first and second auxiliary devices cooperating with a die to insert the mold for molding. There are further provided second cooling devices, first and second lifting devices, first and second lowering devices, and a control device.

Mold clamping conditions, including a predetermined mold gap, a predetermined mold clamping force, a predetermined back pressure for a movable mold, a predetermined mold closing pressure, and a predetermined mold closing pressure adjustment condition associated with the compression state of a molding material, are set beforehand. At the time of molding, an injection filling process for causing the injection device to inject and fill the molding material into a mold of a mold clamping device for which the mold clamping conditions have been set is performed, and, after completion of the injection filling process, a compression process is performed on the basis of the mold clamping conditions including the mold closing pressure adjustment condition.

A polygonal mirror includes a reflecting surface capable of reflecting laser light emitted from a light source, a base material made of a metal material, and a molded member molded outside the base material and including a first surface and a second surface which crosses the first surface and which corresponds to the reflecting surface.

A manufacturing method of a polygonal mirror using a metal mold including a first mold, a second mold, a third mold, and a fourth mold includes a step of forming the molded member by providing the third mold and the fourth mold between the first mold and the second mold in a state in which the third mold and the fourth mold are in contact with each other and then by injecting a resin material into the metal mold, and a step of separating the third mold from the first crossing surface of the molded member in a direction crossing the first crossing surface.

A polygonal mirror includes reflecting surfaces, a molded member including a first surface and a second surface, a contact portion, and gate marks. Each of said first surface and said second surface has a polygonal shape. The contact portion and the gate marks are formed at non-overlapping positions with a line segment connecting a vertex of the polygonal shape with a rotation center. The gate marks and the reflecting surfaces are the same in number. A perpendicular bisector of a line segment connecting centers of the gate marks adjacent to each other with respect to a rotational direction of the polygonal mirror is formed at a position passing through an associated vertex of the polygonal shape and the rotation center.

A mold apparatus includes first and second mold plates that constitute a cassette mold, a first base mold, a base intermediate mold for loading the first mold plate, a second base mold for loading the second mold plate, a base intermediate mold driving device for positioning and fixing the base intermediate mold at any position between the first and second base molds, and a controller for performing control to position and fix the base intermediate mold so that the first mold plate and the first base mold are in contact with each other when a molded product is taken out.

A mold apparatus includes a first mold plate formed with a runner flow path, a second mold plate, a runner stripper plate having a through hole that communicates with the runner flow path, a runner locking part formed with an inverse tapered space which communicates with the through hole and has an inverse tapered shape and in which a locking portion made of a molding material is formed, and a runner unlocking means for moving the runner stripper plate away from the runner locking part to unlock the locking portion.