Disclosed are a water storage tank bladder, a manufacturing method therefor, the water storage tank including the bladder, and a water treatment apparatus including the water storage tank. According to one embodiment of the present invention, the water storage tank bladder used in the water storage tank to receive and store water and discharge the stored water has a lower side of which the thickness can be thicker than the thickness of the upper side of the bladder and thicker than the thickness of the lateral sides of the bladder.

A method for manufacturing a composite preform is provided, including preparing a preform that is formed from a plastic material, preparing a tubular heat shrinkable plastic member that is longer than the preform and has a margin for thermocompression bonding at one end, inserting the preform into the plastic member having the plastic member undergo thermal shrinkage by heating the preform and the plastic member, and bonding the margin of the plastic member by thermocompression.

A pressure vessel including: a cylindrical straight body section and dome sections provided at both ends of the body section, where: the body section and the dome sections are composed of a resin main body, and an outer shell made of a fiber reinforced resin material, the outer shell being on the outside of the main body; each of dome sections has pinch-off regions extending from a tip of the dome section toward the body section; and when an end of each of the pinch-off regions opposite to the tip of the dome section is located in a region where a distance from the tip of the dome section to the end of each of the pinch-off regions opposite to the tip of the dome section in the axial direction of the straight body section is less than a distance from the tip of each of the dome sections to a boundary between the straight body section of the main body and each of the dome sections in the axial direction of the straight body section.

A fuel tank includes: a tank main body made of a resin material; and a cover member which is formed using threads made of a fiber-reinforced composite material containing a thermoplastic resin fusible to a surface of the tank main body. The cover member has a twill weave structure at least in its portion fused to the upper surface of the tank main body. The threads each have a core-sheath structure in which a fiber made of a polypropylene resin is coated with a polyethylene resin.

An object of the present invention is to provide a pressure vessel that is light in weight and has a sufficient internal capacity as well as excellent durability. The present invention provides a pressure vessel (1) including: a cylindrical straight body section (10) and dome sections (11) provided at both ends of the body section (10), wherein: the body section (10) and the dome sections (11) are composed of a resin main body (2), and an outer shell (3) made of a fiber reinforced resin material, the outer shell (3) being provided on the outside of the main body (2); each of dome sections (2b) of the main body (2) has pinch-off regions (12) extending from a tip of the dome section (2b) toward the body section (2a); and when a distance from the tip of each of the dome sections (2b) to a boundary between the body section (2a) of the main body (2) and each of the dome sections (2b) in an axial direction of the body section (2a) is 1, an end (12a) of each of the pinch-off regions (12) opposite to the tip of the dome section (2b) is located in a region where an distance from the tip of the dome section (2b) in the axial direction of the body section (2a) is less than 1.

Disclosed are a water storage tank bladder, a manufacturing method therefor, the water storage tank including the bladder, and a water treatment apparatus including the water storage tank. According to one embodiment of the present invention, the water storage tank bladder used in the water storage tank to receive and store water and discharge the stored water has a lower side of which the thickness can be thicker than the thickness of the upper side of the bladder and thicker than the thickness of the lateral sides of the bladder.

This method for manufacturing a composite preform (70) includes: preparing a preform (10a) that is formed from a plastic material; preparing a tubular heat shrinkable plastic member (40a) that is longer than the preform (10a) and has a margin (80a) for thermocompression bonding at one end; inserting the preform (10a) into the plastic member (40a); having the plastic member (40a) undergo thermal shrinkage by heating the preform (10a) and the plastic member (40a); and bonding the margin (80a) of the plastic member by thermocompression.

A fuel tank includes: a tank main body made of a resin material; and a cover member which is formed using threads made of a fiber-reinforced composite material containing a thermoplastic resin fusible to a surface of the tank main body. The cover member has a twill weave structure at least in its portion fused to the upper surface of the tank main body. The threads each have a core-sheath structure in which a fiber made of a polypropylene resin is coated with a polyethylene resin.

A plastic container assembly includes an outer container and an inner liner or bag, wherein the inner liner or bag is expanded within the outer container. Processes for making a plastic container with an inner liner are also disclosed.

An object of the present invention is to provide a core member for a sandwich panel and a method of forming the core member for the sandwich panel which are capable of attaining a desired profile, a desired pattern on its surface, and a desired inner structure in accordance with an application of the sandwich panel. According to an aspect of the invention, there is provided a thermoplastic resin core member interposed between two resin skin sheets comprising a closed hollow portion located to be inside of a desired position in accordance with an application of the sandwiched panel, and it is formed by clamping parison of a molten thermoplastic resin positioned to be between two split molds so as to exhibit a desired profile and/or a surface shape, two surfaces against each of which the molten parison is pressed to form an adhesive surface on which the corresponding resin skin sheet is formed.