Abstract: A polyester containing aromatic moieties is contacted with microorganisms having the activity of decomposing the polyester to decompose or reduce it. Preferably, either or both of Trichosporon FERM BP-6445 or Arthrobacter FERM BP-6444 was contacted with the polyester to decompose or reduce it. A fiber made of the polyester or a cloth made of such fiber may be reduced by contacting it with the microorganisms having the activity of decomposing the polyester.

Abstract: A polyester containing aromatic moieties is contacted with microorganisms having the activity of decomposing the polyester to decompose or reduce it. Preferably, either or both of Trichosporon FERM BP-6445 or Arthrobacter FERM BP-6444 was contacted with the polyester to decompose or reduce it. A fiber made of the polyester or a cloth made of such fiber may be reduced by contacting it with the microorganisms having the activity of decomposing the polyester.

Abstract: A polyester containing aromatic moieties is contacted with microorganisms having the activity of decomposing the polyester to decompose or reduce it. Preferably, either or both of Trichosporon FERM BP-6445 or Arthrobacter FERM BP-6444 was contacted with the polyester to decompose or reduce it. A fiber made of the polyester or a cloth made of such fiber may be reduced by contacting it with the microorganisms having the activity of decomposing the polyester.

Abstract: A polyester containing aromatic moieties is contacted with microorganisms having the activity of decomposing the polyester to decompose or reduce it. Preferably, either or both of Trichosporon FERM BP-6445 or Arthrobacter FERM BP-6444 was contacted with the polyester to decompose or reduce it. A fiber made of the polyester or a cloth made of such fiber may be reduced by contacting it with the microorganisms having the activity of decomposing the polyester.

Abstract: A polyester fiber is provided, which does not produce a huge amount of residues during its reducing process, and shows good appearance, feeling and superior characteristics as a fiber, such as a high tensile strength and elongation. Such polyester fiber is a conjugate fiber comprising a core spinned from a polyester containing an aromatic moiety and a skin layer surrounding the core, the skin layer spinned from an aliphatic polyester. The skin layer may be easily reduced by contacting it with an alkaline solution or an enzyme, to provide a reduced fiber with good appearance, feeling and superior characteristics as a fiber.

Abstract: An electrically conductive alumina fiber which heretofore known only as electrically insulative is now provided, which comprises an aluminum oxide matrix, and a continuous phase of carbon in the aluminum oxide matrix, the continuous phase of carbon affording an electrically conductive property to the fiber. Also, a method of producing the alumina fiber is disclosed, comprising pyrolyzing a fiber of poly[(acyloxy)aloxane] having a formula ##STR1## wherein, R.sub.1 represents CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.3, R.sub.2 represents ##STR2## or other substituted aromatic group, in an inert atmosphere.

Abstract: An electrically conductive alumina fiber which heretofore known only as electrically insulative is now provided, which comprises an aluminum oxide matrix, and a continuous phase of carbon in the aluminum oxide matrix, the continued phase of carbon affording an electrically conductive property to the fiber. Also, a method of producing the alumina fiber is disclosed, comprising pyrolyzing a fiber of poly[(acyloxy)aloxane)] having a formula ##STR1## wherein, R.sub.1 represents CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.3, R.sub.2 represents ##STR2## or other substituted aromatic group, in an inert atmosphere.