Abstract: This invention relates to a water resistant composition which comprises (A) polyvinyl alcohol, (B) a chitosan of which aqueous 1% solution has a viscosity not greater than 70 centipoise at 20.degree. C. and (C) an aldehyde compound, as well as a heat-sensitive recording sheet which comprises said composition. The composition has excellent water resistant properties and the heat-sensitive recording sheet has improved color forming properties and excellent resistance to water and solvents.

Abstract: A novel composite target material that is composed of a rare earth metal and a transition metal (iron-group metal) and which is used in the formation of a thin magnetooptical recording film by sputtering is disclosed. Also disclosed is a process for producing such composite target material.The process comprises the steps of providing a rare earth metal and an iron-group transition metal as separate entities, mixing these metals without alloying, and hot-forming the mixture at a temperature lower than the eutectic point of the system of metallic components in the mixture, thereby forming an intermetallic compound at the interface between the rare earth metal and the transition metal while causing said metals to be bonded together.The target material produced by this process contains 30-50 wt % of the rare earth metal, with the balance being made of the iron-group transition metal and incidental impurities.

Abstract: This invention relates to a method of coating paper to improve the surface strength and printability thereof comprising applying to the paper a silicon-containing modified polyvinyl alcohol agent or its saponification product. This method gives outstanding results for printing purposes when coated onto paper objects. This invention also relates to a paper having a silicon-containing polyvinyl alcohol agents coated thereon.

Abstract: Water-resistant compositions which comprise a modified polyvinyl alcohol having a silyl group in the molecule and an organic substance, useful as compositions for treating inorganic materials and defogging compositions.

Abstract: A binder for obtaining a ceramic molded green body which comprises a modified polyvinyl alcohol having either (A) a hydrophobic group having a hydrocarbyl group of 4 or more carbon atoms or (A) plus (B) an ionic hydrophilic group in the side chain.

Abstract: Microcapsules having walls formed from polyvinyl alcohol are prepared by dispersing a substantially water insoluble nuclear material in an aqueous solution of a polyvinyl alcohol polymer, which solution has a cloud point, phase separating and depositing a concentrated aqueous solution of the polyvinyl alcohol polymer as a separated phase around said nuclear material from the bulk continuous phase by maintaining the temperature of the system above the cloud point of the aqueous polyvinyl alcohol polymer solution, and subjecting the phase separated solution to conditions which substantially solidify or gel said polyvinyl alcohol polymer in said concentrated aqueous solution of said separated phase around said nuclear material but which do not substantially solidify or gel the polyvinyl alcohol in the diluted aqueous solution of the continuous phase.

Abstract: A centrifuge comprises a pair of sample containers supported, respectively, on opposite ends of a horizontal rotor that is spun by a drive motor about a vertical rotation axis. The sample containers carry storage tanks for fluid that is automatically distributed between the tanks for balancing prior to centrifuging. Any weight imbalance between the loaded sample containers is measured by a pair of pressure transducers located between the rotor and a stationary, annular support member. Electronic circuitry monitors the outputs of the pressure transducers and in response controls a servo operated valve to redistribute the balancing fluid between the storage tanks under the force of an external vacuum source. Digital logic prevents energization of the drive motor for centrifuging the samples until the load is balanced.