A polyimide laminated film includes a porous polyimide layer that has a porosity of from 30% to 90% and pores having a spherical shape and a non-porous polyimide layer that has a porosity of 5% or less.

This disclosure relates to a polyimide polymer that includes the reaction product of: (a) at least one diamine selected from the group consisting of a diamine of Structure (Ia) and a diamine of Structure (Ib),

##STR00001##

(b) at least one diamine of Structure (II),

##STR00002##

(c) at least one tetracarboxylic acid dianhydride, and optionally (d) at least one compound containing a first functional group reactive with an amine or an anhydride and at least a second functional group selected from the group consisting of a substituted or unsubstituted alkenyl group and a substituted or unsubstituted alkynyl group. Each variable in the above formulas is defined in the specification.

Modifying agents for polyolefin resins and laminated films including the modifying agents generally include an ester compound and a nonionic surfactant. The mass ratio of the content of the ester compound to the content of the nonionic surfactant is (ester compound)/(nonionic surfactant)=10/90 to 30/70. The ester compound is at least one selected from the group consisting of partial esters of a dihydric alcohol having 2 to 4 carbon atoms with an aliphatic monocarboxylic acid having 8 to 22 carbon atoms. The nonionic surfactant is at least one selected from the group consisting of a partial ester of a tri- to hexahydric alcohol with an aliphatic monocarboxylic acid having 8 to 22 carbon atoms, a specific ester compound, and a specific ether compound.

The invention relates to a floor underlayment comprising a first layer, a second layer, and an inner layer between the first layer and the second layer, wherein the inner layer has one layer of foam beads, and the floor underlayment has a thickness from 0.8 mm to 1.5 mm. The invention further relates to a method for manufacturing a floor underlayment, a flooring system and a use of a floor underlayment.

A gas barrier film including a substrate film containing a resin, and a gas barrier layer that has oxygen barrier properties and is in contact with at least one surface of the substrate film, a surface of the gas barrier layer has a flat portion, and a plurality of protrusions that protrude from the flat portion. The number of protrusions that satisfy the following formula (1) is 0 to 200 per mm.sup.2, and the number of protrusions that satisfy the following formula (2) is 20 or more per mm.sup.2; d×2≤f(1); and 0.2≤f<d×2(2), where d represents a thickness (μm) of the gas barrier layer, and f represents a height (μm) of each of the plurality of protrusions.

The invention provides a sealant film that is less likely to adsorb components formed of various types of organic compounds, has excellent heat sealing characteristics at 140° C., while having low heat sealing strength at 100° C. and being less likely for heat sealing layers to adhere to each other even when the film is used as a packaging bag and the content thereof is warmed in boiling water. The sealant film has at least one heat sealing layer consisting of a polyester component, wherein a heat sealing strength of the heat sealing layer being heat sealed to another heat sealing layer at 100° C. and 0.2 MPa for 2 seconds is 0-5 N/15 mm and at 140° C. and 0.2 MPa for 2 seconds is 8-30 N/15 mm, and a film density including all layers is 1.20 or more and less than 1.39.

A separator includes a porous substrate, and a porous layer formed on one or both surfaces of the substrate and containing a polyvinylidene fluoride type resin and a filler, in which the filler content in the porous layer is from 30 to 80% by mass with respect to the total mass of the polyvinylidene fluoride type resin and the filler, and the polyvinylidene fluoride type resin is at least one resin selected from the following resin A and B: resin A: a copolymer having a weight average molecular weight of from 100,000 to 350,000, and a content of HFP is more than 5% by mass but not more than 11% by mass; and resin B: a copolymer having a weight average molecular weight of from 100,000 to 1,000,000, in which a content of HFP is more than 11% by mass but not more than 15% by mass.

A filler-containing film has a structure in which fillers are held in a binder resin layer. The average particle diameter of the fillers is 1 to 50 μm, the total thickness of the resin layer is 0.5 times or more and 2 times or less the average particle diameter of the fillers, and the ratio Lq/Lp of, relative to the minimum inter-filler distance Lp at one end of the filler-containing film in a long-side direction, a minimum inter-filler distance Lq at the other end at least 5 m away from the one end in the film long-side direction is 1.2 or less. The fillers are preferably arranged in a lattice form.

Films having high light transmission values, low haze and high glass transition temperatures and useful, for example, as optical protection films and zero-zero optical retardation films, are prepared using one or more copolymers of methyl methacrylate having certain characteristics.

An object of the present invention is to provide a polymer film having a low dielectric loss tangent and a small difference in a linear expansion coefficient from that of a copper foil; and a laminate. The polymer film of an embodiment of the present invention is a polymer film including a liquid crystal polymer, in which a hardness A at a distance of half of a thickness of the polymer film and a hardness B at a distance of 1/10 of the thickness of the polymer film satisfy a relationship of Expression (1A), and in a case where positions at distances of 1/10, 4/10, and 6/10 of the thickness of the polymer film are defined as a position T1, a position T2, and a position T3, respectively; and a region from the one surface to the position T1 is defined as a first surface layer region, and a region from the position T2 to the position T3 is defined as a central region, a void area proportion X in the first surface layer region and a void area proportion Y in the central region satisfy a relationship of Expression (2A).
(Hardness A+Hardness B)/2≥0.10 GPa  Expression (1A)
Void area proportion Y−Void area proportion X≥0.10%  Expression (2A)