Injection moulding method

A method of assembling a support, comprising:

• providing a frame;
• injection moulding a polymeric resin to form an article that is suitable for strain orientation, the injection moulding comprising:
• providing a polymeric resin comprising a thermoplastic polyester elastomer;
• heating the resin to form a molten resin at a temperature of at least 240° C.;
• injecting the molten resin into a mould of a moulding apparatus to substantially fill the mould and form an article, wherein at least part of the article is a sheet part with a plurality of members that are integrally formed into the sheet part, with apertures provided between at least some of the members of the sheet part to form a mesh;
• and
• removing the formed article from the mould, wherein at least the sheet part of the article is suitable for strain orientation;
• wherein the formed article has an as moulded dimension less than a corresponding dimension of the frame;
• stretching at least part of the sheet part of the formed article so that the formed article has a stretched dimension greater than the corresponding dimension of the frame and such that strain orientation of at least part of the sheet part of the formed article occurs;
• relaxing the at least part the sheet part of the formed article so that the formed article has a post-relaxation dimension between the as moulded dimension and the stretched dimension;
• and
• supporting the formed article from the frame after the step of relaxing.

A method of forming a support surface for a chair, the method comprising:

• providing a polymeric resin comprising a thermoplastic polyester elastomer;
• heating the resin to form a molten resin at a temperature of at least 240° C.;
• injecting the molten resin into a mould of a moulding apparatus to substantially fill the mould and form an article, wherein at least part of the article is a sheet part with a plurality of members that are integrally formed into the sheet part, with apertures provided between at least some of the members of the sheet part to form a mesh;
• and
• removing the formed article from the mould, wherein at least the sheet part of the article is suitable for strain orientation, and wherein the formed article is a support surface for a chair.

A method of injection moulding a polymeric resin to form an article that is suitable for strain orientation, the method comprising:

• providing a polymeric resin comprising a thermoplastic polyester elastomer;
• heating the resin to form a molten resin at a temperature of between 240° C. and 260° C.;
• injecting the molten resin into a mould of a moulding apparatus through a nozzle to substantially fill the mould to form an article, wherein the mould comprises at least one gate for delivering resin into a part of the mould where the article is to be formed, wherein the mould is at a temperature of at least 50° C., wherein the step of injecting comprises passing the molten resin through the nozzle at a temperature of between 240° C. and 260° C., and wherein the step of injecting comprises injecting at least a major part of the molten resin with a velocity of between 1000 mm/second and 2000 mm/second at the or each gate;
• wherein at least part of the article is a sheet part with a plurality of members that are integrally formed into the sheet part, with apertures provided between at least some of the members of the sheet part to form a mesh, wherein the method comprises holding the resin in the mould at a hold pressure of less than 22 MPa during curing of the article;
• and
• removing the formed article from the mould, wherein at least the sheet part of the article is suitable for strain orientation, and wherein the formed article is a support surface to be supported from a frame of a chair.