Abstract: A hot melt adhesive composition comprising (A) 60 to 98 wt. % of a propylene-ethylene copolymer, (B) 2 to 40 wt. % of a maleic anhydride-modified polypropylene wax having a softening point of 120 to 170° C. and serving as a tackifier, and when required, (C) an antioxidant in an amount of 0.1 to 5.0 wt. % based on the combined amount of (A) and (B).

Abstract: The present invention provides a lubricant for recording media that does not readily decompose, and which has high adhesion to recording media, and a magnetic disk that is durable against continuous sliding under high-speed rotation. The present invention provides a lubricant for recording media containing: a perfluoropolyether compound represented by Formula (1), R1—CH2CF2O—(CF2CF2O)m—(CF2O)n—CF2CH2—R2??(1) wherein R1 represents R represents a C1-4 haloalkyl group, R2 represents —OCH2CH(OH)CH2OH, and m and n are each independently 1-30; and another perfluoropolyether compound represented by Formula (2), R1—CH2CF2O—(CF2CF2O)m—(CF2O)n—CF2CH2—R3??(2) wherein R1, m and n are as defined above and R3 represents —OCH2CH(OH)CH2OCH2CH(OH)CH2OH. The present invention also provides a magnetic disk having a lubricating layer essentially consists of such a lubricant.

Abstract: A method of producing a hot melt adhesive solid, the method comprising the steps of inserting a hot melt adhesive heated to higher than a flow temperature into a container having a mold-releasing internal surface and a bottom plate which is openable and closable or removably fixable to the container, cooling the hot melt adhesive at least until the surface of hot melt adhesive becomes solidified, and taking out the hot melt adhesive from the container by opening the bottom plate or displacing the same; hot melt adhesive solid; method of packaging the same; and method of transporting the same.

Abstract: A compound of the formula (I), a lubricant and a magnetic disk using the compound A—CH2CF2O(CF2CF2O)m-(CF2O)n-CF2CH2—B ??(I) wherein A is amino group having hydroxyl group, B is hydroxyl group, or amino group having or not having hydroxyl group, wherein m is a real number of 5 to 36, and n is a real number of from 4 to 30.

Abstract: A phosphazene compound of the formula (1) or (5) which has an arrangement such that perfluoroxyalkylene units selected from —CF2O— and —CF2CF2O— are randomly distributed, the compound having a functional terminal group A or group G A—OCH2CF2O(CF2CF2O)p(CF2O)qCF2CH2O—A  (1) G—[OCH2CF2O(CF2CF2O)p(CF2O)qCF2CH2OH]6-z  (5) wherein A is a group of the formula (a) and G is a group of the formula (g) shown in the specification, and a lubricant containing at least one of the phosphazene compounds of the formulas (1) and (5).

Abstract: The present invention provides a lubricant for magnetic recording medium which comprises, as an effective component, a phosphazene compound of formula [N═P[O(C6H4)—(A)z—R]a[OCH2—(B)xH]b]y  (1) wherein A is —C6H4— or —OC6H4—, B is fluorine-containing alkylene group, R is hydrogen atom, fluorine atom, C1-4 alkyl, C1-4 alkoxy or C1-4 haloalkyl, a and b are a real number of 0 to 2, satisfying a+b=2, x is 1, 2, 3 or 4, y is 3 or 4, and z is 0 or 1.

Abstract: The present invention provides flexibility in the shape and material of the cleaning vessel, enables high-power transmission of ultrasonic waves, and reduces audible noise generation. An ultrasonic cleaning machine according to the invention comprises an acoustic lens mounted above an ultrasonic transducer which is immersed in oil held within an external tank as well as a cleaning vessel holding a cleaning liquid further above the acoustic lens so that ultrasonic waves produced by the ultrasonic transducer converge at a point within the cleaning liquid. In one form of the invention, the cleaning vessel is eliminated and the cleaning liquid is held directly in the external tank.