Process for producing shaped film
AssigneesMitsui Chemicals, Inc., Hopnic Laboratory Co., Ltd.
InventorsHiroyuki Kamio, Yoshimitsu Aiiso
Life of this patent
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Abstract
The method of the present invention for producing a shaped film includes a step of arranging a thermoplastic resin film to divide a space into a first space located on one surface side of the film, and a second space located on the other surface side, a step of heating the thermoplastic resin film, a step of curving the thermoplastic resin film in one space by using a difference in pressure between the first space and the second space, a step of stopping the curving step of the thermoplastic resin film in a state where at least a convex curved surface of both surfaces of the film is exposed into the space, and a step of cooling the curved film.
Claims21
A process for producing a shaped film, comprising:
- a step of arranging a thermoplastic resin film in a first shaping member having a first space which opens to one side, thereby covering an opening, wherein one surface of the thermoplastic resin film is exposed to the first space, wherein the thermoplastic resin film is fixed to an end of the opening of the first shaping member by a fixing member and the thermoplastic resin film is arranged to divide the first space on one surface side of the thermoplastic film from a second space located on the other surface side,
- a step of heating the thermoplastic resin film,
- a step of curving the thermoplastic resin film into a semispherical shape film into one space by controlling a difference in pressure between the first space and the second space while uniquely determining a radius of curvature of the thermoplastic resin film in accordance with a relationship of the radius of curvature of the thermoplastic resin film with the difference in pressure and an elastic force of the thermoplastic resin film, wherein the thermoplastic resin film is permitted to curve at the end of the opening of the first shaping member and the fixing member,
- a step of stopping the curving step of the thermoplastic resin film in a state where at least a convex curved surface of the film is exposed into the space, and
- a step of cooling the curved thermoplastic resin film,
- wherein the step of curving the thermoplastic resin film comprises:
- applying a predetermined difference in pressure between the first space and the second space,
- detecting a change in position of the thermoplastic resin film, thereby obtaining the radius of curvature of the thermoplastic resin film,
- adjusting the difference in pressure between the first space and the second space, in accordance with a relationship of the difference in pressure with the elastic force of the thermoplastic resin film and the obtained radius of curvature of the thermoplastic resin film, and
- applying the adjusted difference in pressure between the first space and the second space.
Dependencies are inferred from the claim text.