A film and method of forming a film provides an unmodified starting layer of a starting material, the starting layer having opposed first and second surfaces and an initial thickness, T.sub.1, and a modified surface layer of thickness T.sub.2, which is less than T.sub.1, formed in at least a portion of the second surface, wherein a portion of the modified surface layer is not supported by unmodified starting material removed from the first surface opposite the modified surface layer.

Disclosed are preforms which incorporate improvements in the region of the neck and upper segment of the body to allow the production of lightweight containers, such as bottles suitable for containing water or other beverages. In accordance with certain embodiments, the improvements include a thinner neck finish area than conventional bottles, where the thinner area is extended into the upper segment of the body portion below the support ring. Reducing the thickness in these areas of the bottle allows for less resin to be used in forming the preform and bottle.

Regarding a laser welded body in which a laser transmissive/absorptive molding member containing a PBT-based material and a laser absorptive molding member containing a PBT-based material are integrated with each other by laser welding, the following laser welded body is proposed as a laser welded body in which a bond strength can be further increased. A laser welded body having a structure in which a member I and a member II are integrally bonded to each other, the member I contains 0.0005 to 5.0 parts by mass, with respect to 100 parts by mass of a polyester-based resin A, of a laser transmissive/absorptive coloring material capable of transmitting and absorbing laser beam, and the polyester-based resin A contains at least a polybutylene terephthalate copolymer resin, the member II contains 0.15 to 10.00 parts by mass, with respect to 100 parts by mass of a polyester-based resin B, of a laser absorptive coloring material not transmitting but capable of absorbing laser beam, and the polyester-based resin B contains (B1) a homo PBT, (B2) a homo PBT-based mixed resin containing a homo PBT, or (B3) a copolymerized PBT-based mixed resin containing a copolymerized PBT.

Regarding a laser welded body in which a laser transmissive/absorptive molding member containing a PBT-based material and a laser absorptive molding member containing a PBT-based material are integrated with each other by laser welding, the following laser welded body is proposed as a laser welded body in which a bond strength can be further increased. A laser welded body having a structure in which a member I and a member II are integrally bonded to each other, the member I contains 0.0005 to 5.0 parts by mass, with respect to 100 parts by mass of a polyester-based resin A, of a laser transmissive/absorptive coloring material capable of transmitting and absorbing laser beam, and the polyester-based resin A contains at least a polybutylene terephthalate copolymer resin, the member II contains 0.15 to 10.00 parts by mass, with respect to 100 parts by mass of a polyester-based resin B, of a laser absorptive coloring material not transmitting but capable of absorbing laser beam, and the polyester-based resin B contains (B1) a homo PBT, (B2) a homo PBT-based mixed resin containing a homo PBT, or (B3) a copolymerized PBT-based mixed resin containing a copolymerized PBT.

The present invention relates to a method for producing foam and foam produced thereby. The method for producing foam includes a step for producing foam by kneading and injection molding a first extrusion product and a second extrusion product, wherein the first extrusion product is obtained by extruding a first composition including an aromatic vinyl-based resin, and the second extrusion product is obtained by extruding a second composition including a polyamide resin and a foaming agent.

Preform assembly for blow moulding a container, comprising at least a first and a second perform, wherein the first perform is positioned inside the second perform before blow moulding the performs into the container, wherein each perform has a body forming portion having a wall thickness of less than about 8 millimetres, preferably less than about 6 mm.

A phase difference film solely consisting essentially of a single species of copolymer P containing a polymerization unit A and a polymerization unit B, the phase difference film having a phase separation structure that exhibits a structural birefringence, and the phase difference film having an NZ factor of greater than 0 and smaller than 1; and the production method therefor. Preferably, the phase separation structure has a form of any of lamella, cylinder and spheroid, and the distance between phases in the phase separation structure is 200 nm or less.

Disclosed are preforms which incorporate improvements in the region of the neck and upper segment of the body to allow the production of lightweight containers, such as bottles suitable for containing water or other beverages. In accordance with certain embodiments, the improvements include a thinner neck finish area than conventional bottles, where the thinner area is extended into the upper segment of the body portion below the support ring. Reducing the thickness in these areas of the bottle allows for less resin to be used in forming the preform and bottle.

A three-dimensional model built with an extrusion-based digital manufacturing system, and having a perimeter based on a contour tool path that defines an interior region of a layer of the three-dimensional model, where at least one of a start point and a stop point of the contour tool path is located within the interior region of the layer.

Preform assembly for blow moulding a container, comprising at least a first and a second perform, wherein the first perform is positioned inside the second perform before blow moulding the performs into the container, wherein each perform has a body forming portion having a wall thickness of less than about 8 millimetres, preferably less than about 6 mm.