This invention relates to the flexible packaging, either as sheet, roll, bag, sachet, or other forms, which is biodegradable and edible, and could be used as packaging for solid, semisolid, and liquid, which is featured by the composition of biopolymers, at least two of different natural and renewable biopolymers, and the manufacturing method thereof.

This invention relates to the flexible packaging, either as sheet, roll, bag, sachet, or other forms, which is biodegradable and edible, and could be used as packaging for solid, semisolid, and liquid, which is featured by the composition of biopolymers, at least two of different natural and renewable biopolymers, and the manufacturing method thereof.

Provided is a rubber composition having excellent adhesiveness to a metal member even if no cobalt salt is contained. The rubber composition contains a rubber component, a rubber-metal adhesion promoter containing Bi, and an organic acid salt of metal other than Bi, where a content of metal element other than Bi with respect to a content of Bi element (content of metal element other than Bi/content of Bi element) in the rubber composition is more than 14 and 100 or less in terms of molar ratio, a content of the rubber-metal adhesion promoter is more than 1.5 parts by mass with respect to 100 parts by mass of the rubber component, and the amount of substance of metal element other than Bi contained in the organic acid salt of metal other than Bi in the rubber composition is 0.01 mol or more.

Provided is a rubber composition having excellent adhesiveness to a metal member even if no cobalt salt is contained. The rubber composition contains a rubber component, a rubber-metal adhesion promoter containing Bi, and an organic acid salt of metal other than Bi, where a content of metal element other than Bi with respect to a content of Bi element (content of metal element other than Bi/content of Bi element) in the rubber composition is more than 14 and 100 or less in terms of molar ratio, a content of the rubber-metal adhesion promoter is more than 1.5 parts by mass with respect to 100 parts by mass of the rubber component, and the amount of substance of metal element other than Bi contained in the organic acid salt of metal other than Bi in the rubber composition is 0.01 mol or more.

A rubber composition that includes a rubber component, an inorganic fiber material, and a coupling agent. The inorganic fiber material is one or more inorganic fiber materials selected from the group consisting of a magnesium sulfate fiber, a calcium silicate fiber, a potassium titanate fiber, an aluminum borate fiber, and a glass fiber.

A rubber composition that includes a rubber component, an inorganic fiber material, and a coupling agent. The inorganic fiber material is one or more inorganic fiber materials selected from the group consisting of a magnesium sulfate fiber, a calcium silicate fiber, a potassium titanate fiber, an aluminum borate fiber, and a glass fiber.

A rubber composition that includes a rubber component, an inorganic fiber material, and a coupling agent. The inorganic fiber material is one or more inorganic fiber materials selected from the group consisting of a magnesium sulfate fiber, a calcium silicate fiber, a potassium titanate fiber, an aluminum borate fiber, and a glass fiber.

The present invention relates to a hydrous silica for rubber reinforcing fillers having CTAB specific surface area in the range of 220 to 350 m.sup.2/g and a pore volume over the range of pore radius 1.9 to 100 nm measured by mercury press-in method in the range of 1.7 to 2.0 cm.sup.3/g, wherein a volume average particle diameter D50 in a volume particle size distribution measured by laser diffraction method for the slurry obtained by dispersing 50 ml of a hydrous silica slurry adjusted to 4 mass % with an ultrasonic homogenizer at an output of 140 W for 10 minutes is in the range of 5.0 to 12.0 μm, and a cumulative value of hydrous silica particles over the range of 4.0 to 35.0 μm in the volume particle size distribution is 80% or more. The present invention also relates to a rubber composition containing the above-mentioned hydrous silica and a rubber component containing a natural rubber. The present invention provides a hydrous silica which has equivalent or excellent reinforcing property (abrasion resistance, tensile strength) and which allows to greatly reduce the rolling resistance when it is blended into a rubber based on the natural rubber for TBRs, which is often used under a heavy load, compared with conventional hydrous silicas, and provides the rubber composition containing the hydrous silica.

The present invention relates to a hydrous silica for rubber reinforcing fillers having CTAB specific surface area in the range of 220 to 350 m.sup.2/g and a pore volume over the range of pore radius 1.9 to 100 nm measured by mercury press-in method in the range of 1.7 to 2.0 cm.sup.3/g, wherein a volume average particle diameter D50 in a volume particle size distribution measured by laser diffraction method for the slurry obtained by dispersing 50 ml of a hydrous silica slurry adjusted to 4 mass % with an ultrasonic homogenizer at an output of 140 W for 10 minutes is in the range of 5.0 to 12.0 μm, and a cumulative value of hydrous silica particles over the range of 4.0 to 35.0 μm in the volume particle size distribution is 80% or more. The present invention also relates to a rubber composition containing the above-mentioned hydrous silica and a rubber component containing a natural rubber. The present invention provides a hydrous silica which has equivalent or excellent reinforcing property (abrasion resistance, tensile strength) and which allows to greatly reduce the rolling resistance when it is blended into a rubber based on the natural rubber for TBRs, which is often used under a heavy load, compared with conventional hydrous silicas, and provides the rubber composition containing the hydrous silica.

In a first aspect, the present invention is directed to a rubber composition comprising 70 phr to 90 phr of styrene butadiene rubber, wherein said styrene butadiene rubber comprises a first styrene butadiene rubber having a glass transition temperature within a range of −49° C. to −15° C. and a second styrene butadiene rubber having a glass transition temperature within a range of −50° C. to −89° C. Furthermore, the rubber composition comprises from 10 phr to 30 phr of one or more of natural rubber and synthetic polyisoprene rubber, 100 phr to 200 phr of silica, and at least 25 phr of at least one terpene resin having a weight average molecular weight (Mw) of at most 1000 g/mol. Moreover, the invention is directed to a tire comprising such a rubber composition, in particular in the tread of the tire.