There is provided an interlayer film for laminated glass with which positional displacement between two lamination glass members can be prevented. The interlayer film for laminated glass according to the present invention is arranged between a first lamination glass member and a second lamination glass member to obtain laminated glass, the interlayer film contains a thermoplastic resin and a plasticizer, when, in the MD direction of the interlayer film, a birefringence index of the first surface part, a birefringence index of the second surface part, and a birefringence index of the center part are defined as ?nMDA, ?nMDB, and ?nMDC, respectively, ?nMDA, ?nMDB, and ?nMDC each are 0.50?10.sup.?3 or less, and the glass transition temperature of the interlayer film is 33? C. or less or the content of the plasticizer in the interlayer film is 35 parts by weight or more relative to 100 parts by weight of the thermoplastic resin in the interlayer film.

There is provided an interlayer film for laminated glass with which protrusion of an interlayer film portion in the TD direction can be suppressed at the time of producing laminated glass. In the interlayer film for laminated glass according to the present invention, when, in the MD direction of the interlayer film, a birefringence index of the first surface part, a birefringence index of the second surface part, and a birefringence index of the center part are defined as ?nMDA, ?nMDB, and ?nMDC, respectively, the interlayer film satisfies the first requirement: ?nMDA being larger than ?nMDC, ?nMDB being larger than ?nMDC, and ?nMDA, ?nMDB, and ?nMDC each being 0.12?10.sup.?3 or less or the interlayer film satisfies the second requirement: ?nMDA being larger than ?nMDC, ?nMDB being larger than ?nMDC, ((?nMDA??nMDC)/(?nMDC))<0.5, and ((?nMDB-?nMDC)/(?nMDC))<0.5.

There is provided an interlayer film for laminated glass with which protrusion of an interlayer film portion in the TD direction can be suppressed at the time of producing laminated glass. In the interlayer film for laminated glass according to the present invention, when, in the MD direction of the interlayer film, a birefringence index of the first surface part, a birefringence index of the second surface part, and a birefringence index of the center part are defined as ?nMDA, ?nMDB, and ?nMDC, respectively, ?nMDA, ?nMDB, and ?nMDC each are 0.25?10.sup.?3 or less.

There is provided an interlayer film for laminated glass with which an interlayer film portion is less liable to protrude at the time of producing laminated glass. In the interlayer film for laminated glass according to the present invention, when, in the MD direction of the interlayer film, a birefringence index of the first surface part, a birefringence index of the second surface part, and a birefringence index of the center part are defined as nMDA, nMDB, and nMDC, respectively, in the TD direction of the interlayer film, a birefringence index of the first surface part, a birefringence index of the second surface part, and a birefringence index of the center part are defined as nTDA, nTDB, and nTDC, respectively, a higher absolute value among the absolute value of the difference between nMDA and nMDC and the absolute value of the difference between nMDB and nMDC is defined as nMDMAX, and a higher absolute value among the absolute value of the difference between nTDA and nTDC and the absolute value of the difference between nTDB and nTDC is defined as nTDMAX, the total of nMDMAX and nTDMAX is 0.07010.sup.3 or less.

The present invention aims to provide an interlayer film for a laminated glass having recesses in the shape of engraved lines on both surfaces to exhibit excellent deaeration properties in production of a laminated glass and suppressing formation of a moire pattern when unwound from a rolled body thereof. The present invention also aims to provide a laminated glass including the interlayer film for a laminated glass, a method for producing an embossing roll suitably used for production of the interlayer film for a laminated glass, and a method for producing the interlayer film for a laminated glass. The present invention relates to an interlayer film for a laminated glass, having a large number of recesses on both surfaces, the recesses each having a groove shape with a continuous bottom and being regularly adjacent and parallel to each other, the interlayer film having a glossiness on a surface with the large number of recesses measured in conformity with JIS Z 8741-1997 of higher than 3% or a haze value measured in conformity with JIS K 7105-1981 of 87% or lower.

The present invention provides an interlayer film for a laminated glass which is easily peelable without autohesion even after storage in a stacked state, a laminated glass prepared using the interlayer film for a laminated glass, and a method for producing the interlayer film for a laminated glass. The present invention provides an interlayer film for a laminated glass, having a large number of recesses on at least one surface, the at least one surface having the recesses having an arithmetical mean height Sa of 200 nm or more as measured in conformity with ISO 25178.

The present invention relates to a heating element composition capable of three-dimensional molding and a film heater formed therefrom. Specifically, the present invention relates to a heating element composition capable of three-dimensional molding and a film heater formed therefrom, wherein the heating element composition has high extensibility and excellent high temperature durability which is in a conflicting relationship with extensibility, so that mechanical damage such as cracks during stretching can be suppressed, has the characteristic of being stably maintained in a molded shape rather than being restored to an original shape after molding, like conventional stretchable materials, can minimize the change rate of resistance when deformed by three-dimensional molding, can be cured at 150 C. or less, and can form a heating element by various printings or coatings so as to be applied to various film heaters.

A PVB film for HUD, wherein an accuracy error of HUD imaging achievable by the PVB film is 0.1 mrad, wherein a cross section of the PVB film in one direction is wedged, and a cross section of the PVB film in another direction is curved.

Resin compositions, layers, and interlayers comprising a poly(vinyl acetal) resin that includes residues of an aldehyde other than n-butyraldehyde are provided. Such compositions, layers, and interlayers can exhibit enhanced or optimized properties as compared to those formulated with comparable poly(vinyl n-butyral) resins.

Resin compositions, layers, and interlayers comprising two or more thermoplastic polymers and at least one RI balancing agent for adjusting the refractive index of at least one of the resins or layers is provided. Such compositions, layers, and interlayers exhibit enhanced optical properties while retaining other properties, such as impact resistance and acoustic performance.