Toyo Boseki Kabushiki Kaisha

Toyobo Co., Ltd.

Nippon Magphane Co., Ltd.

Nippon Magphane Kabushiki Kaisha

Yasuhiro Nishino

Katsuaki Kuze

Hideto Ohashi

Osamu Makimura

Shigeji Konagaya

Yujiro Matsuyama

Katsuhiko Nose

Naoki Mizuno

Chikao Morishige

Toshitake Suzuki

Tadashi Okudaira

Masahiro Kobayashi

Hideki Sugihara

Kozo Maeda

Tsuyoshi Hongo

Haruo Matsumoto

Shigenori Iwade

The present invention provides a laminated thermoplastic resin film which is excellent in adhesion and blocking resistance. A laminated thermoplastic resin film has a covering layer containing a copolymerized polyester resin and a polyurethane resin on one side or both sides of a thermoplastic resin film, characterized in that the covering layer has a microphase-separated or nanophase-separated structure in polyester (PE) phase A comprising a copolymerized polyester resin as a main component and polyurethane (PU) phase B comprising a polyurethane resin as a main component, and when the covering layer is observed by a scanning probe microscopy in phase measurement mode, an area ration (surface fraction of PEs) of polyester phase A (which indicates a dark phase in phase image) of the surface of the covering layer defined by following the formula (1) is 35% or more and less than 90% per 20 a measurement area of 5 &#x3bc;m&#xd7;5 &#x3bc;m.Surface fraction of PEs (%)=(area of PEs phase A/measurement area)&#xd7;100.&#x2003;&#x2003;(1)

Laminated thermoplastic resin film and laminated thermoplastic resin film roll

A biaxially oriented polyester film comprising silica particles (A) having an average secondary particle size of 50-200 nm, an average primary particle size ratio (length/breadth) of 1.25-3.0 and the ratio of average primary particle size/standard deviation of primary particle size (d/&sgr;) of 0.5-5.0 in a proportion of 0.01-1% by weight, and inactive particles (B) having an average particle size of 300-1500 nm in a proportion of 0.01-1% by weight. The polyester film of the present invention can be adapted to a high speed feeding of a film or tape in the production line and stand the use of economical parts in an attempt to achieve decreasing the costs of tapes.

Oriented polyester film

A polyester film containing organic particles comprising a matrix polymer and fine polymer particles is provided. The fine particles are interpenetrating network type cross-linked fine polymer particles, each particle containing, in its cross-linked polymer network, a hydrophilic polymer in an amount of 1 to 40% by weight which is not substantially bonded to the cross-linked polymer chemically. The cross-linked polymer is a vinyl type polymer or a siloxane type polymer comprising as its main components a polymerizable monomer and at least one cross-linking monomer contained in an amount of 5% by weight or more based on the total weight of the monomers. The interpenetrating network type cross-linked fine polymer particles have an average particle size in the range of 0.01 to 5 .mu.m and are contained in the film in an amount of 0.001 to 5.0% by weight.

Film containing organic particles

A biaxially oriented polyester film of a polyester composed of an aromatic dicarboxylic acid as a major acid component and at least one glycol component, said polyester film containing 100-20000 ppm of a particulate compound oxide composed of two or more metals (selected from Al, B, Si, Ti, Zr, W, and Fe) and oxygen whose average primary particle diameter is 0.005-0.1 .mu.m. The compound oxide contains 0.1-5 wt % by weight of chlorine. The polyester film finds use as a base film for magnetic tape with improved scratch resistance.

Biaxially oriented polyester film

An oriented polyester film having at least one surface being roughened by containing inactive particles and three-dimensional surface roughness exponents of the said roughened surface are within ranges simultaneously satisfying the following relationships (I) to (III), while the number of coarse projections is in excess of the fourth grade:

An oriented polyester film comprising ethylene terephthalate as the major repeating units, which comprises 0.01 to 1.0% by weight of silica particles and/or titanium dioxide particles having each an average particle size of 0.01 to 0.5.mu. and 0.005 to 1.0% by weight of calcium carbonate having an average particle size of 0.01 to 0.5.mu., which provides an oriented polyester film for the base film of video tape which has a flatness on the surface and has excellent slipperiness, abrasion resistance and running characteristics as well as excellent magnetic transducer characteristics.

Growing community of inventors

Tsuruga, Japan

Yasuhiro Nishino