Process for producing molded product, and heat-exchange membrane element
A molded product including a film bonded to a resin frame is produced by a method including: 1) reinforcing the film with a solvent-soluble or solvent-disintegrable reinforcing layer; 2) inserting the reinforced film in an injection mold; 3) feeding a resin to the mold to attach a frame body to the reinforced film while injection molding the resin frame; and 4) treating the resulting injection molded product with a solvent to remove the reinforcing layer. This production process can establish a technique capable of bonding (integrally molding) the film solely to the frame body, regardless of the size of the film. The film may preferably be an expanded porous polytetrafluoroethylene film, and the moisture-permeable resin may preferably be combined with the expanded porous polytetrafluoroethylene film.
1. A process for producing a molded product comprising a film bonded to a resin frame body, said process comprising:
reinforcing the film with a solvent-soluble or solvent-disintegrable reinforcing layer;
inserting the reinforced film in an injection mold;
feeding a resin to the mold to attach a frame body to the reinforced film while injection molding the resin frame; and
treating the resulting injection molded product with a solvent to remove the reinforcing layer
wherein the film is a porous expanded polytetrafluoroethylene film.
2. The process for producing a molded product according to claim 1 , wherein a moisture-permeable resin is combined with the expanded porous polytetrafluoroethylene film.
3. The process for producing a molded product according to claim 2 , wherein the moisture-permeable resin is selected from the group consisting of urethane resins, cross-linked polyvinyl alcohols and ion exchange fluororesins.
4. The process for producing a molded product according to claim 1 , wherein the film has a thickness from about 0.5 μm to about 100 μm.
5. The process for producing a molded product according to claim 1 , wherein the solvent is water and the reinforcing layer is formed of a water-soluble fiber.
6. The process for producing a molded product according to claim 1 , wherein the solvent is water, and
wherein the reinforcing layer is a formed product of a polyvinyl alcohol fiber or a paper formed of a pulp fiber capable of being finely dispersed in water.
7. The process for producing a molded product according to claim 1 , wherein the film reinforced with a reinforcing layer is inserted between a pair of molds for injection molding, each said mold being provided with a first cavity and a second cavity for formation of a frame body, and
wherein each said mold is provided an engraved mold surface on an inner side of each said mold between said first cavity and said second cavity.
8. A process for producing a molded product comprising a film bonded to a resin frame body, said process comprising:
reinforcing the film with a solvent-soluble or solvent-disintegrable reinforcing layer;
inserting the reinforced film in an injection mold;
feeding a resin to the mold to attach a frame body to the reinforced film while injection molding the resin frame; and
treating the resulting injection molded product with a solvent to remove the reinforcing layer,
wherein the solvent is water and the reinforcing layer is formed of a water-soluble fiber.
9. A process for producing a molded product comprising a film bonded to a resin frame body, said process comprising:
reinforcing the film with a solvent-soluble or solvent-disintegrable reinforcing layer;
inserting the reinforced film in an injection mold;
feeding a resin to the mold to attach a frame body to the reinforced film while injection molding the resin frame; and
treating the resulting injection molded product with a solvent to remove the reinforcing layer,
wherein the solvent is water, and
wherein the reinforcing layer is a formed product of a polyvinyl alcohol fiber or a paper formed of a pulp fiber capable of being finely dispersed in water.