Abstract: Cooperating hard and soft paper calendering rolls have probes for measuring the soft roll's temperature at different zones along its length and units for controlling the nip line pressure in each zone in dependence of the zone's measured temperature.

Abstract: Molded articles of polymerized lactams are prepared by pumping of a catalyst containing partial lactam melt at a temperature of .+-.1.degree. C. of a temperature in the range of 160.degree. C. to 170.degree. C. and a lower temperature activator containing partial lactam melt at a temperature of .+-.1.degree. C. of a temperature in the range of 160.degree. C. to 170.degree. C. to which activator addition is delayed relative to catalyst addition, with separate gear pumps to a mixing zone maintained between 170.degree. and 175.degree. C., the pumps connected to the mixing zone by straight feed tubes positioned at an angle of inclination to the horizontal of a maximum of 10.degree., each feed tube having a volume of at least one-third greater than the pump to which it is connected and form the mixing zone into a mold. At least part of the gases released are returned to the mixing zone by the tube systems and gear pumps. The products formed crumble on being heated to a temperature of approximately 220.degree. C.

Abstract: Molded articles of polymerized lactams are prepared by pumping of a catalyst containing partial lactam melt at a temperature of .+-.1.degree. C. of a temperature in the range of 160.degree. C. to 170.degree. C. and a lower temperature activator containing partial lactam melt at a temperature of .+-.1.degree. C. of a temperature in the range of 160.degree. C. to 170.degree. C. to which activator addition is delayed relative to catalyst addition, with separate gear pumps to a mixing zone maintained between 170.degree. and 175.degree. C., the pumps connected to the mixing zone by straight feed tubes positioned at an angle of inclination to the horizontal of a maximum of 10.degree., each feed tube having a volume of at least one-third greater than the pump to which it is connected and form the mixing zone into a mold. At least part of the gases released are returned to the mixing zone by the tube systems and gear pumps. Apparatus to carry out the method is also provided.

Abstract: An electrically insulated rail joint having two integral plastic fishplates with embedded steel reinforcement bolted on opposite sides of the rail joint. Each fishplate is provided with vertical spaced projecting ribs having wedge-shaped faces engaging the rail sides.

Abstract: Disclosed are catalysts for the polymerization of higher lactam monomers. The catalysts comprise an essentially homogenic binary mixture of lauric-lactam and a salt of lauric-lactam.The inventive catalyst can be stored at room temperature without making special provisions to avoid any access of air and moisture.

Abstract: The invention concerns a process for the preparation of dicyclopentylene [2,2'-bis(4-alkyl-6-t-butylphenols)] of the formula I ##STR1## wherein R.sub.1 is tertiary butyl andR.sub.2 is methyl or ethyl,by the reaction of 1.5 to 2.5 moles of a 4-alkyl-6-t-butyl-phenol of the formula II ##STR2## wherein R.sub.1 and R.sub.2 are as defined above, with 0.8 to 1.2 moles dicyclopentadiene at a temperature between 20.degree. and 120.degree. C. in the presence of an organic solvent and borontrifluoride or a complex thereof as catalyst, characterised by employment of specially selected solvents and reaction under practically anhydrous conditions.

Abstract: A controlled deflection roll system includes a rotative cylindrical shell having an outside adapted to form a nip with a counter roll, a non-rotative shaft extending axially through and radially spaced from the shell's inside and having projecting ends to which force is applied to press the shell against the counter roll. Inside the shell pressure elements press the shell in the same direction, the counter roll providing a reaction, and because the shell does not have its ends journaled on the shaft, the shaft can float inside the shell in dependence on the forces involved. Automatic devices automatically responsive to any radial displacement of the shaft relative to the shell control the force applied to the shaft's ends so as to keep the shaft centered at its ends within the shell, permitting the application of a rotary drive to the shell.

Abstract: In order to obtain better heat transfer in a coolable roller with an inner supporting cylinder which consists of metal, and on which a tubular roller jacket is firmly disposed, the jacket consisting of plastic and having slots on its inner circumference, the inner cylinder is constructed so that it can be cooled from the inside and a pressure resistant heat conductor which is in heat conducting contact with the walls of the slots is disposed in the slots.

Abstract: In an arrangement for the continuous treatment, especially washing, of spread out liquid permeable textile material in web form, several deflection cylinders, over which the material is conducted and at which liquid on the side of the textile material facing the deflection cylinders is pushed through the textile material, are provided in pairs close together but not touching each other, with the textile material in web form passing immediately from one deflection cylinder of the pair to the other. The deflection cylinder of each pair following the other in the web travel direction is being arranged lower than the preceding deflection cylinder of the pair, so that the textile material runs substantially vertically over a short section when passing from the preceding to the following deflection cylinder of each pair.

Abstract: A paper calender using a polyurethane coated calendering cylinder is operated with the coating maintained at an unusually low temperature found to prevent damage to the coating when calendering at high speeds and pressures.

Abstract: In order to determine the homogeneity of a magnetic dispersion, part of the dispersion is conducted through a measuring cell prior to its application to a base, the size, number and type of those regions of the magnetic dispersion which interfere with the homogeneity being determined with the aid of magnetic measurements. The measuring cell contains a magnetic head, a magnetic dispersion is made to flow in a stream of constant cross section past the air gap of the magnetic head, and a magnetic field at least partially penetrating the magnetic dispersion is produced. From the characteristics of the amplified output voltage of the magnetic head the various parameters of the inhomogeneities in the magnetic dispersion can then be ascertained.

Abstract: Molded articles of polymerized lactams are prepared by pumping of a catalyst containing partial lactam melt at a temperature of .+-. 1.degree. C. of a temperature in the range of 160.degree. C. to 170.degree. C. and a lower temperature activator containing partial lactam melt at a temperature of .+-. 1.degree. C. of a temperature in the range of 160.degree. C. to 170.degree. C. to which activator addition is delayed relative to catalyst addition, with separate gear pumps to a mixing zone maintained between 170 and 175.degree. C., the pumps connected to the mixing zone by straight feed tubes positioned at an angle of inclination to the horizontal of a maximum of 10.degree., each feed tube having a volume of at least one-third greater than the pump to which it is connected and form the mixing zone into a mold. At least part of the gases released are returned to themixing zone by the tube systems and gear pumps. Apparatus to carry out the method is also provided.

Abstract: A process and apparatus for the manufacture of magnetic recording media, in which, immediately before the magnetic dispersion is applied to a base, the dispersion is subjected to shear by means of a disc rotatably mounted in a housing, by introducing it at the center of rotation of the disc and forcing it through a gap formed between the face of the disc and the wall of the housing, which gap tapers toward the rim of the disc.

Abstract: A flexible multilayer magnetic recording medium exhibiting an improved signal-to-print-through ratio coupled with an improved maximum output level and diminished dc noise, comprising a non-magnetic base and, applied thereto, at least two superposed layers consisting of a binder with magnetizable particles uniformly dispersed therein, the upper magnetic layer containing a magnetic pigment giving a signal-to-print-through ratio of less than 55db and the lower magnetic layer(s) containing a magnetic pigment giving a signal-to-print-through ratio of 55 db or more.

Abstract: The corner of a structural member has first, second, third and fourth surfaces which converge to form the corner with first, second and third layers of fiber reinforced material successively applied to the corner surfaces to form the walls of the corner. The first layer of fiber reinforced material completely covers the first and second surfaces and partially covers the third and fourth surfaces. The second layer completely covers the second and fourth surfaces and that part of the third surface which remained uncovered by the first layer, and the third layer completely covers the first and third surfaces and that part of the fourth surface which remained uncovered by the first layer. The three layers arranged in this manner therefore produces corner walls having a thickness corresponding to two of the layers. The fibers in the two layers forming the walls extend in directions transverse to each other and form patterns different from each other.

Abstract: Improved tube bundle-type heat exchanger comprising at least one tube base cast from a plastic material, such as poly laurin lactam, with a tube bundle cast in the tube base. Several optional features are also disclosed.

Abstract: In a tubular filter bodies with at least one tubular filter structure with a porous wall, through which a liquid passes substantially radially, particles above a given size being held back at the entrance surface, made of porous plastic, ceramic material, metal, graphite, etc, continuous operation at constant pressures is made possible by providing at least one groove (or slot) which is closed toward the outside and forms a forced flow path leading from an inlet to an outlet in the circumferential entrance surface of the tubular filter body.

Abstract: A method and apparatus for continuously coating a thread or core with a thermoplastic is disclosed wherein a flowing stream of the plastic, in the form of a melt or liquid monomer is used to convey the core from one or more elongated and heated guide tubes into and through one or more elongated and cooled molding tubes axially aligned with each guide tube whereby the thread or core is automatically centered in the tubes and a uniform outer coating of hardened plastic is applied. The liquid monomer can be treated with a suitable activator or catalyst before entry into the mold tubes or at an intermediate mixing zone located between the exit part of the guide tubes and the inlet part of the cooling tubes. The mixing zone is larger in volume than the tubes and provides an off-center convolution about the exit ports of the guide tubes and coaxial conical exit ports converging into the entry ports of the molding tubes.

Abstract: Flexible multi-layer magnetic recording media comprising a non-magnetic flexible base and, applied thereto, two superposed magnetizable layers which contain a homogeneous mixture of acicular magnetic chromium dioxide in an organic binder.According to the invention, the magnetizable layer adjacent to the base contains a chromium dioxide having a specific surface area, measured by the BET method, of from 15 to 25 m.sup.2 /g, while the outer magnetic layer contains a chromium dioxide having a specific surface area, measured by the BET method, of from 26 to 35 m.sup.2 /g.Such magnetic recording media are distinguished by uniformly high sensitivity over the entire audible frequency range even if close manufacturing tolerances are not maintained.

Abstract: A fluorescent screen whose fluorescent material is a pure rare earth compd such as a compound of the formulas (A.sub.2 O).sub.a (Ln.sub.2 O.sub.3).sub.b (P.sub.2 O.sub.5).sub.c, (Ln.sub.2 O.sub.3).sub.p (Al.sub.2 O.sub.3).sub.q (B.sub.2 O.sub.3).sub.r, or LnZrF.sub.7 wherein a is zero or an integer greater than zero, b, c, p, q, and r are integers greater than zero, A is at least one alkali metal, and Ln is at least one rare earth metal.