POLYVINYL ACETAL RESIN FILM, AND LAMINATE COMPRISING SAME
The present invention relates to a polyvinyl acetal resin film, comprising a polyvinyl acetal resin material, wherein at least one surface has a relative diffuse reflectance of 3% or higher at a wavelength of 550 nm, an absolute difference between the relative diffuse reflectance of one surface at a wavelength of 550 nm and that of the other surface at a wavelength of 550 nm is 0.5% or larger, and the amount of a plasticizer in the polyvinyl acetal resin film is 0 to 20% by mass based on a total mass of the polyvinyl acetal resin film.
1 . A polyvinyl acetal resin film, comprising a polyvinyl acetal resin material,
wherein
at least one surface of the polyvinyl acetal resin film has a relative diffuse reflectance of 3% or higher at a wavelength of 550 nm,
an absolute difference between the relative diffuse reflectance of one surface at a wavelength of 550 nm and that of the other surface at a wavelength of 550 nm is 0.5% or larger, and
the polyvinyl acetal resin film comprises a plasticizer in an amount of from 0 to 20% by mass based on a total mass of the polyvinyl acetal resin film.
2 . The polyvinyl acetal resin film according to claim 1 , wherein the polyvinyl acetal resin material comprises a polyvinyl acetal resin, and
a viscosity of a toluene/ethanol (1:1, mass ratio) solution containing 10%-by-mass of the polyvinyl acetal resin contained, which is measured at 20° C. and 30 rpm using a Brookfield-type viscometer, is 100 mPa·s or higher.
3 . The polyvinyl acetal resin film according to claim 1 , having a thickness of from 10 to 350 μm.
4 . The polyvinyl acetal resin film according to claim 1 , wherein the polyvinyl acetal resin film comprises a polyvinyl acetal resin in an amount of 75% by mass or more based on the total mass of the polyvinyl acetal resin film.
5 . A functional layer-equipped polyvinyl acetal resin film, comprising a functional layer on at least one surface of the polyvinyl acetal resin film according to claim 1 .
6 . The functional layer-equipped polyvinyl acetal resin film according to claim 5 , wherein the functional layer is a conductive layer.
7 . The functional layer-equipped polyvinyl acetal resin film according to claim 6 , wherein a material constituting the conductive layer comprises silver or copper.
8 . The functional layer-equipped polyvinyl acetal resin film according to claim 6 , wherein the conductive layer comprises plural linear conductive materials having a line width of from 1 to 30 μm.
9 . A method of producing the functional layer-equipped polyvinyl acetal resin film according to claim 5 , the method comprising:
coating, printing, or laminating a material constituting the functional layer on at least one surface of the polyvinyl acetal resin film.
10 . A laminate, comprising:
a transparent substrate; and
the polyvinyl acetal resin film according to claim 1 .
11 . A laminate, comprising the polyvinyl acetal resin film according to claim 1 between plural transparent substrates.
12 . The laminate according to claim 10 , further comprising a plasticized polyvinyl acetal resin layer.
13 . The laminate according to claim 10 , wherein the transparent substrate is a glass.
14 . A vehicle, comprising:
a glass comprising the laminate according to claim 10 .
15 . A laminate, comprising:
a transparent substrate; and
the functional layer-equipped polyvinyl acetal resin film according to claim 5 .
16 . A laminate, comprising the functional layer-equipped polyvinyl acetal resin film according to claim 5 between plural transparent substrates.