A light diffusion plate is configured to be assembled with a blue light source module having blue Mini LEDs to form a white light backlight module. The light diffusion plate is added with organic dyes with light-emission wavelength of 490-650 nm in order to convert the blue light into white light. The light diffusion plate is made by a foaming extrusion process and contains a plurality of micro-bubbles with a size of 60-400 μm and a weight-reduction ratio of 15-25% for improving the uniformity of white light and resolving the MURA problem. The size of micro-bubbles is controlled by reducing the temperature of at the exit end of the T-die head, such that the wavelength of the white light emitted from the light diffusion plate can be narrower to achieve the effect of wider color gamut display.

A thermoplastic polyester resin foam sheet includes a foam layer containing a thermoplastic polyester resin, in which a number average molecular weight Mn of the thermoplastic polyester resin is 9,000 to 26,000, a Z-average molecular weight Mz is 240,000 to 710,000, and a content of acetaldehyde in the foam layer is 25 ppm by mass or less.

A thermoplastic polyester resin foam sheet includes a foam layer containing a thermoplastic polyester resin, in which a number average molecular weight Mn of the thermoplastic polyester resin is 9,000 to 26,000, a Z-average molecular weight Mz is 240,000 to 710,000, and a content of acetaldehyde in the foam layer is 25 ppm by mass or less.

In general, the present invention is directed to a continuous method of making a polymer foam by using a polymer having a first monomeric component and a second monomeric component. The method employs a tandem type extruder having a first extruder and a second extruder. The method disclosed herein can provide a foam having a desired cell size, cell density, porosity, foam density, and/or thermal conductivity, etc. In turn, the polymer foams produced according to the present method can have numerous applications, such as thermal insulation applications for appliances including ovens, freezers, refrigerators, etc.

Films may be used as interleaves between hard and non-compressible surfaces such as surfaces of sheets or plates made of glass, metal, such as steel, polycarbonate, and/or poly(methyl methacrylate). The films may be embossed and/or may include a foamed core layer having a plurality of micro-voids. In particular, the films may include a polyolefin, a basis weight of between about 30 gsm and about 70 gsm, an embossed thickness of between about 150 microns and 800 microns, and a stiffness of between about 150 grams and about 750 grams according to the Circular Bend Stiffness Test.

Films may be used as interleaves between hard and non-compressible surfaces such as surfaces of sheets or plates made of glass, metal, such as steel, polycarbonate, and/or poly(methyl methacrylate). The films may be embossed and/or may include a foamed core layer having a plurality of micro-voids. In particular, the films may include a polyolefin, a basis weight of between about 30 gsm and about 70 gsm, an embossed thickness of between about 150 microns and 800 microns, and a stiffness of between about 150 grams and about 750 grams according to the Circular Bend Stiffness Test.

A method of manufacturing a polyolefin foam sheet composition includes extruding a polyolefin sheet, irradiating the extruded sheet to obtain a physically crosslinked sheet, foaming the physically crosslinked sheet with heat to obtain a foamed layer, and skiving the foamed layer to obtain a foam sheet with at least one skived surface. The surface roughness of the skived surface of the foam sheet is different from the surface roughness of an unskived surface.

The present invention relates to the use of a composition comprising from 60-98 wt. % of polypropylene, from 2-40 wt. % of aromatic polycarbonate and from 0.1-10 wt. % of compatibiliser for the manufacture of a foamed article, wherein the compatibiliser is a BAB or AB type of block copolymer comprising a polypropylene block A and a polyester or polycarbonate block B, or wherein the compatibiliser is a graft copolymer of the type ABn having a polypropylene backbone A and polyester or polycarbonate block(s) B grafted thereon, with n being at least 1, and wherein the polyester or polycarbonate blocks B have an average M/F ratio from 2-25, wherein M is the number of backbone carbon atoms in the polyester or polycarbonate not including carbonyl carbon atoms, and F is the number of ester or carbonate groups in the polyester or polycarbonate block, and wherein the wt. % is based on the sum of the amount polypropylene, polycarbonate and compatibiliser.

The present invention relates to the use of a composition comprising from 60-98 wt. % of polypropylene, from 2-40 wt. % of aromatic polycarbonate and from 0.1-10 wt. % of compatibiliser for the manufacture of a foamed article, wherein the compatibiliser is a BAB or AB type of block copolymer comprising a polypropylene block A and a polyester or polycarbonate block B, or wherein the compatibiliser is a graft copolymer of the type ABn having a polypropylene backbone A and polyester or polycarbonate block(s) B grafted thereon, with n being at least 1, and wherein the polyester or polycarbonate blocks B have an average M/F ratio from 2-25, wherein M is the number of backbone carbon atoms in the polyester or polycarbonate not including carbonyl carbon atoms, and F is the number of ester or carbonate groups in the polyester or polycarbonate block, and wherein the wt. % is based on the sum of the amount polypropylene, polycarbonate and compatibiliser.

According to an example aspect of the present invention, there is provided an extrusion foaming method for producing low-density extrusion foam from a thermoplastic cellulose-based starting material.