Agency of Industrial Science and Technology

Ministry of International Trade & Industry

Chisso Corporation

Gunze Limited

Kazuo Nakayama

Masao Kato

Hachiro Nakanishi

Hiro Matsuda

Yoshio Tanaka

Yoshikazu Ikeda

Yoichi Taguchi

Takashi Masuda

Akihiro Oishi

Takeshi Shimamoto

Junichiro Yokota

Susumu Arase

Hiroshi Takasu

Ken-ichi Fujita

Yutaka Ishigami

Takashige Oka

Suon H Hyon

Minori Adachi

Akira Kaito

Hisae Nakahara

Shinichi Kinugasa

A process of producing a polyester or copolyester, wherein at least one cyclic lactone of the following formula (I):

Aliphatic polyester and process for the production thereof

Bone-treating devices made of biodegradable polymers having a high-density and a high-orientation along the major axis, which have a density of 1.260 g/cm.sup.3 or more (when measured by the sink and float method) and which possess the bending strength and the bending strength-retaining characteristic defined by the following equations:

Bone-treating devices and their manufacturing method

The present invention provides a process for preparing rolled heat-treated films or sheets of a crystalline thermoplastic resin in which heat shrinkage is notably improved, formability is excellent and tensile strength in a transverse direction is increased. The process of the present invention comprises the steps of rolling a crystalline thermoplastic resin material between at least one pair of rolls at a temperature which is lower than the melting point of the resin material but higher than room temperature, and then successively subjecting the resin material to a heat treatment at a temperature which is higher than the rolling temperature but lower than the melting point of the resin material. The heat treatment is carried out for a time (t: seconds) satisfying the formula ##EQU1## wherein d is the thickness (mm) of the rolled films or sheets, r is the thickness reduction rate of the rolled films or sheets, Tr is the rolling temperature (.degree.C.), Ta is the heat treatment temperature (.degree.C.), and Tm is the melting point (.degree.C.) of the crystalline resin.

Process for preparing rolled heat-treated films or sheets

##STR1## (wherein R.sub.1 and R.sub.2 independently stand for at least one member selected from the class consisting of alkylene groups, substituted alkylene groups, cycloalkylene groups, substituted cycloakylene groups, arylene groups, and substituted arylene groups), is a novel diacetylene-nylon salt compound possessing two kinds of ability of solid-state polymerization, and two-dimensional macromolecular crystals are obtained by severally polymerizing the diacetylene moiety and the nylon salt moiety of the compound. A shaped article of hig rigidity is produced by filling a mold with the aforementioned salt and subjecting the salt in the mold to simultaneous application of heat and pressure.

Diacetylene-nylon salt compound and method for production of

##STR1## (wherein R.sub.1 and R.sub.2 independently stand for at least one member selected from the class consisting of alkylene groups, substituted alkylene groups, cycloalkylene groups, substituted cycloalkylene groups, arylene groups, and substituted arylene groups), is a novel diacetylene-nylon salt compound possessing two kinds of ability of solid-state polymerization, and two-dimensional macromolecular crystals are obtained by severally polymerizing the diacetylene moiety and the nylon salt moiety of the compound. A shaped article of high rigidity is produced by filling a mold with the aforementioned salt and subjecting the salt in the mold to simultaneous application of heat and pressure.

Growing community of inventors

Ushiku, Japan

Kazuo Nakayama