Functional fiber sheet
A functional sheet is coated with physically vapor-deposited film including titanium oxide and other metallic oxides for making the film transparent so color and pattern on the fiber sheet are visible, providing electric conductivity to the film, improving the productivity of vapor deposition and enabling selective blocking of infrared and ultraviolet radiation.
1. A functional fiber sheet comprising synthetic fiber, at least one face thereof being coated with a physically vapor-deposited transparent film comprising metallic oxides, wherein said metallic oxides comprise a mixture of an ordinary oxide as a main component and a small amount of oxides having a lower valence than said ordinary oxide as a secondary component, wherein said metallic oxide is titanium oxide, its ordinary oxide being a tetravalent oxide and said lower valence oxides being divalent or trivalent oxides, and the amount of lower valence oxides to the total amount of the metallic oxides is 0.1 to 20 wt %.
2. The functional fiber sheet described in claim 1 wherein the thickness of said physically vapor-deposited film is 5 to 500 nm.
3. The functional fiber sheet as set forth in claim 1 wherein the synthetic fiber comprises synthetic fiber used in usual knit and woven use.
4. The functional fiber sheet as set forth in claim 1 wherein the synthetic fiber comprises polyester fiber, nylon fiber, acrylic fiber or polyimide fiber.
5. A method for manufacturing a functional fiber sheet comprising the steps of:
forming a physically vapor-deposited transparent film of metallic oxides on a fiber sheet through a physical vapor deposition process;
forming an ordinary oxide as a main component of the metallic oxides of the physically vapor-deposited transparent film by increasing the amount of oxygen to be supplied during the physical vapor deposition process; and
forming a small amount of oxides having a lower valence than said ordinary oxide as a secondary component of the metallic oxides by lowering the amount of oxygen to be supplied to the physical vapor deposition process,
wherein said metallic oxide is titanium oxide, its ordinary oxide being a tetravalent oxide and said lower valence oxides being divalent or trivalent oxides, and the amount of lower valence oxides to the total amount of the metallic oxides is 0.1 to 20 wt %.