Synthetic polymer film whose surface has microbicidal activity, multilayer structure having synthetic polymer film, sterilization method with the use of surface of synthetic polymer film, method for reactivating surface of synthetic polymer film, mold for production of synthetic polymer film, and mold manufacturing method
A synthetic polymer film includes a surface which has a plurality of first raised portions, wherein a two-dimensional size of the plurality of first raised portions is in a range of more than 20 nm and less than 500 nm when viewed in a normal direction of the synthetic polymer film; and the surface has a microbicidal effect.
1. A method for treating a gas or liquid by bringing the gas or liquid into contact with a surface of a synthetic polymer film comprising the surface which has a plurality of first raised portions, wherein a two-dimensional size of the plurality of first raised portions is in a range of more than 20 nm and less than 500 nm when viewed in a normal direction of the synthetic polymer film; wherein the synthetic polymer film further comprises a plurality of second raised portions superimposedly formed over the plurality of first raised portions and a two-dimensional size of the plurality of second raised portions is smaller than the two-dimensional size of the plurality of first raised portions and does not exceed 100 nm;
a static contact angle of the surface with respect to hexadecane is not more than 51°; and
the surface has a microbicidal effect, thereby reducing a number of microorganisms in the gas or liquid.
2. The method for treating the gas or liquid of claim 1 , wherein a static contact angle of the surface with respect to hexadecane is not more than 31°.
3. The method for treating the gas or liquid of claim 1 , wherein a static contact angle of the surface with respect to water is not more than 133°.
4. The method for treating the gas or liquid of claim 1 , wherein an adjoining distance of the plurality of first raised portions is more than 20 nm and not more than 1000 nm.
5. The method for treating the gas or liquid of claim 1 , wherein a height of the plurality of first raised portions is not less than 50 nm and less than 500 nm.
6. The method for treating the gas or liquid of claim 1 , wherein the plurality of first raised portions are capable of warping when corning in contact with a microorganism.
7. The method for treating the gas or liquid of claim 1 , wherein a normal to a lateral surface of the plurality of first raised portions forms an inclination angle with respect to a direction perpendicular to the normal direction of the synthetic polymer film, and the inclination angle varies continuously or discontinuously with respect to a distance from a tip end of the plurality of first raised portions in the normal direction of the synthetic polymer film.
8. The method for treating the gas or liquid of claim 1 , wherein the plurality of second raised portions include a generally conical portion.
9. The method for treating the gas or liquid of claim 1 , wherein a height of the plurality of second raised portions is more than 20 nm and not more than 100 nm.
10. The method for treating the gas or liquid of claim 1 , wherein the synthetic polymer film further comprises a lubricant.
11. The method for treating the gas or liquid of claim 10 , a HLB value of the lubricant is less than 7.
12. The method for treating the gas or liquid of claim 1 , wherein the surface is treated with a mold releasing agent.
13. The method for treating the gas or liquid of claim 1 , wherein the surface is treated with an oil.
14. A synthetic polymer film comprising a surface which has a plurality of first raised portions, wherein
a two-dimensional size of the plurality of first raised portions is in a range of more than 20 nm and less than 500 nm when viewed in a normal direction of the synthetic polymer film; wherein the synthetic polymer film further comprises a plurality of second raised portions superimposedly formed over the plurality of first raised portions and a two-dimensional size of the plurality of second raised portions is smaller than the two-dimensional size of the plurality of first raised portions and does not exceed 100 nm;
the surface has a microbicidal effect;
a static contact angle of the surface with respect to hexadecane is not more than 51°; and
the synthetic polymer film further comprises a lubricant.
15. A multilayer structure, comprising:
a synthetic polymer film comprising a surface which has a plurality of first raised portions, wherein a two-dimensional size of the plurality of first raised portions is in a range of more than 20 nm and less than 500 nm when viewed in a normal direction of the synthetic polymer film, and the surface has a microbicidal effect; wherein the synthetic polymer film further comprises a plurality of second raised portions superimposedly formed over the plurality of first raised portions and a two-dimensional size of the plurality of second raised portions is smaller than the two-dimensional size of the plurality of first raised portions and does not exceed 100 nm; a static contact angle of the surface with respect to hexadecane is not more than 51°; and
a cover film whose surface is provided with an oil,
wherein the cover film is arranged such that the oil provided to the surface of the cover film comes in contact with the plurality of first raised portions.
16. A method for reactivating a surface of a synthetic polymer film, comprising the steps of:
(a) providing a synthetic polymer film comprising a surface which has a plurality of first raised portions, wherein a two-dimensional size of the plurality of first raised portions is in a range of more than 20 nm and less than 500 nm when viewed in a normal direction of the synthetic polymer film, and the surface has a microbicidal effect, the synthetic polymer film having a microorganism adhering to the surface; wherein the synthetic polymer film further comprises a plurality of second raised portions superimposedly formed over the plurality of first raised portions and a two-dimensional size of the plurality of second raised portions is smaller than the two-dimensional size of the plurality of first raised portions and does not exceed 100 nm, and a static contact angle of the surface with respect to hexadecane is not more than 51°; and
(b) removing the microorganism by wiping the surface with a cloth soaked with water or alcohol.
17. The method for treating the gas or liquid of claim 1 , wherein the synthetic polymer film and the plurality of first raised portions are comprised of a common UV curable polymer material and are made by rolling over a moth-eye mold having a surficial nanostructure, which imprints the plurality of first raised portions on the synthetic polymer film.