Abstract: A method for the continuous production of foam materials, wherein the foaming and/or foamed synthetic starting material is passed through the pressure zone (4) of a continuously operating press (1), and in which method at least a part of the heat required for foaming is produced in the synthetic starting material itself as dielectric heat of an electromagnetic high-frequency condenser field, wherein production of this heat in the starting material takes place at least to its greatest part within a high-frequency condenser field which is arranged in the direction of passage (8) of the material through the press (1) in front of the pressure zone (4), and that in order to supply additional heat into the foaming and/or foamed starting material or in order to prevent or delay its surface cooling, at least one of the electrodes (10, 11) between which prevails the high-frequency field and/or at least one of the pressure surfaces of the press may be heated.

Abstract: A process for the preparation of a fiberboard, including the steps of:providing a fiber layer or mat;forming at least one layer of expandable phenol resin particles over and/or under the surfaces of the fiber layer; andhot pressing the resulting superimposed layers to allow the expandable phenol resin particles to expand and to fill the void space within the fiber layer and to consolidate the fiber layer.

Abstract: Fire retardant polystyrene insulating material is manufactured from expandable polystyrene scrap in admixture with a phenol-formaldehyde or melamine-formaldehyde resin in resole form, the resin containing a blowing agent and a surfactant. The insulating material is formed from the scrap-resin mix by applying dielectric heating to foam the resin, and cure the foamed resin to a closed cell structure.

Abstract: Expandable phenolic resin-coated composite beads comprise an aggregate having coated thereon a solid, expandable resin composition comprising a solid, phenolic resin initial condensation product, a foaming agent and, if necessary, a hardening agent. The expandable phenolic resin-coated composite beads provide composite cellular moldings in which the aggregates are uniformly dispersed in a phenolic resin-expanded layer and are firmly adhered to the expanded layer. The composite cellular moldings can be adhered to a face plate to form integral laminates.

Abstract: A liquid mixture containing a heat-expandable resin and a catalyst is cast onto a lower facing, which is heated from below to cause expansion of the mixture and hardening of its lower part. The upper surface of the expanding mixture is covered with an upper facing applied while that portion is still soft, and the composite formed thereby is introduced to a heated enclosure while the upper part remains soft. The thickness of the formed composite, and panels derived thereof, is calibrated or limited by opposed conveyors within said thermal enclosure, which limits the maximum expansion to a value less than the theoretical potential expansion of the foam, allowing hardening to be completed, and subsequent cutting of the composite into panels.

Abstract: Fire retardant polystyrene insulating material is manufactured from expandable polystyrene beads in admixture with a phenol-formaldehyde or melamine-formaldehyde resin in resole form, the resin containing a blowing agent and a surfactant. The insulating material is formed from the bead-resin mix by applying dielectric heating to foam the resin, expand the beads, and cure the foamed resin to a closed cell structure.

Abstract: A matrix coating system and method of manufacture thereof is presented wherein the matrix coating contains chemical blowing agents which permit low pressure molding and also the formation of printing plates having deep relief. The method of manufacture is such that a foamed coating is produced which at molding temperatures is highly compressible at low pressures and which also expands into the relief or nonprinting regions of the pattern plate. The unusually low molding pressures necessary result in less distortion of rubber pattern plates or made from photo polymers. In addition, the combination of high compressibility in appropriate areas, and of volume expansion in relief areas allows the board coating to conform before and during cure to pattern plates of deep relief, so that in the cured state there results a rigid, durable high fidelity mold useful for molding numerous flexographic printing plates.

Abstract: The present invention is directed to a method of producing phenolic foams comprising introducing into a substantially closed volume a phenolic resole resin foamable composition and allowing the composition to foam in this volume wherein a pressure in excess of ambient atmospheric pressure is achieved within this volume. This pressure in excess of ambient atmospheric pressure generally is in excess of about 2 pounds per square inch, typically in excess of about 5 pounds per square inch, and preferably in excess of about 6 pounds per square inch, gauge pressure.The present invention is also directed to foams produced by the method of the invention.

Abstract: A thermal and acoustic insulating plate comprising an aminoplastic resin and a fiber reinforcement embedded therein in the form of a non-woven body of glass fibers extending uniformly throughout the entire volume of the plate. In preparing the plate a non-woven body of glass fibers is impregnated with aminoplastic resin, whereafter the resulting structure is expanded and cured in a mould by supplying heat energy thereto.

Abstract: Closed cell phenol-aldehyde foam is prepared by a method which includes a novel frothing and curing technique. An admixture containing a liquid phenol-aldehyde resole resin, a volatile blowing agent, and a surfactant is frothed to produce a stable froth containing closed cells. The cell walls are formed of the liquid resole resin and the closed cells are expanded by the blowing agent in gaseous phase. The froth is formed into an uncured shape and the liquid resole resin is cured to the solid state in the presence of an acid catalyst to produce cured closed cell foam. The internal temperature throughout the shape during curing is above the boiling point of the blowing agent but less than 212.degree. F., and is sufficiently low to prevent further expansion of the shape in an amount to rupture the closed cell walls and thereby form an open cell structure.

Abstract: A method of filling a cavity in a building block with aminoplast resin foam comprises locating a template (6,7) against and in sealing relation to that face of the block having said cavity opening therefrom characterized in that an aperture (5) defined in said template and at least as large as the opening in the block which communicates with the cavity is aligned and registered with said opening, followed by passing curable aminoplast resin foam into the cavity under pressure to fill said cavity and form an upstand (9) of foam relative to the face of the block in the space defined by the thickness of the template, and then removing the template to leave at least some of said upstand projecting from said face.

Abstract: A foaming apparatus for manufacturing insulation material includes a mixing chamber, a pump for withdrawing the composition from the mixing chamber and supplying it to the apex of a hollow conical expansion chamber where the apex is located vertically beneath the base of the cone, a cover for the base of the cone including an outlet in the form of a nozzle which imparts a desired shape to the foamed composition.

Abstract: A method for the continuous fabrication of blankets or sheets of expanded phenolic resin displaying a hard skin on each of their sides, according to which a mixture, comprising in particular a resole resin, a blowing agent and a hardening catalyst is placed on an essentially flat surface of a moving element, is brought to foam and is conformed between two parallel surfaces entrained in the same direction, the lower surface being situated in the same plane as the surface of the moving component, characterized in that, in a first stage, the mixture is brought into free air towards the conformation surfaces by being submitted to a heating so as to have it expand and then the expanded mass is conformed by exerting a pressure on its free side, at the moment of entry between the conformation surfaces, and the hardening of the resin is completed while maintaining the pressure and the heating.

Abstract: An acidic electroplating bath containing, as a surfactant, a compound of the formula:R--Ar--O--(C.sub.3 H.sub.6 O).sub.n --(C.sub.2 H.sub.4 O).sub.m --Hwherein R is at least one halide, aldehyde, amine, carboxyl, ketone or mixture thereof, Ar is benzene or naphthalene, n is from zero to 10, m is from zero to 100, and m+n is greater than zero.

Abstract: Polyvinyl chloride tube having a crosslinked thin layer of about 0.1 to about 1 micron in thickness at least on its inner surface, thereby substantially reducing the migration and volatilization of plasticizers and other additives from the polymeric materials into the fluid in said tube. The tube of this invention is especially useful for medical use.

Abstract: A panel comprising fillers embedded in a closed cell expanded phenolic resin is made by making a mixture, which is initially fluid, or phenolic resin, a hardening agent, a surface active agent and a porogenic agent, which has a boiling point above ambient temperature and below the polycondensation temperature of the mixture. This liquid mixture is mixed with fillers, for example balls or microspheres of glass or expanded material such as polystyrene. The resulting mixture is placed in a mould, only partially filling the mould, and heated progressively to a temperature in the neighborhood of the boiling point of the porogene agent, while evacuating the mould, and held at that temperature until the mixture has expanded to fill the mould. The temperature is then progressively increased to the polycondensation temperature to harden the expanded mixture.

Abstract: A porous thermoplastic sheet is formed by adding a material to a polymer latex to passivate the aqueous phase of the latex. An additional material of a preselected particle size, corresponding to the desired pore size of the final product is then added. The latex composition is gelled and is then formed into a sheet. The sheet is dried and cured or sintered and the solubles are extracted therefrom with a solvent. A preferred polymer latex is PTFE.

Abstract: A method for the continuous fabrication of blankets or sheets of expanded phenolic resin displaying a hard skin on each of their sides, according to which a mixture, comprising in particular a resole resin, a blowing agent and a hardening catalyst is placed on an essentially flat surface of a moving conveyor, is completely expanded, and is conformed eventually between two parallel surfaces entrained in the same direction, the second surface being located above and substantially parallel to and able to move at the same speed as the moving surface, characterized in that, in a first stage, after having been distributed at the surrounding temperature and in the liquid state along the whole width of the surface of the transport component, in such a way so as to comprise a blanket of expandable liquid mixture essentially uniform in thickness, the expandable mixture is conveyed in the open air towards the conformation surfaces while being submitted to a heating so that it expands, the degree of heating and the lengt

Abstract: A panel comprising fillers embedded in a closed cell expanded phenolic resin is made by making a mixture, which is initially fluid, of phenolic resin, a hardening agent, a surface active agent, a finely divided hydrophilic material and a porogenic agent, which has a boiling point above ambient temperature and below the polycondensation temperature of the mixture. This liquid mixture is mixed with fillers, for example balls or microspheres of glass or expanded material such as polystyrene. The resulting mixture is placed in a mould, only partially filling the mould, and heated progressively to a temperature in the neighborhood of the boiling point of the porogene agent, while evacuating the mould, and held at that temperature until the mixture has expanded to fill the mould. The temperature is then progressively increased to the polycondensation temperature to harden the expanded mixture.

Abstract: Bonded non-woven mineral fibre mat is made by a process including the steps of forming a foam from an aqueous solution or suspension of a binder, impregnating a non-woven mat with the foam and then selectively removing a major portion of the water from the mat prior to setting and/or curing the binder.

Abstract: Here is disclosed a method of manufacturing building blocks filled with a cured aminoplast resin foam by forming a curable foam, presenting the cavity to and in sealing relationship with one end of a delivery pipe for the foam and injecting the curable foam through the delivery pipe into the cavity until a back pressure is developed in the delivery pipe. Apparatus for manufacturing the building blocks is also described.

Abstract: Stable foams of reaction resins and/or condensation resins can be obtained by adding a blowing agent which is gaseous under normal conditions to the resin under pressure, the gas liquid interface being enlarged while dispensing with moving equipment, allowing the mixture to expand and to cure.

Abstract: A strong, expanded moulded panel or board, having a specific gravity between 0.2 and 0.8, is produced by heating dry urea formaldehyde resin containing 4% to 8% volatile materials in a mould at between 130.degree. and 160.degree. C under light restraining pressure between 30 and 300 psi which permits moderate expansion of the resin owing to the gasification of the volatile materials.

Abstract: Expanded urea formaldehyde products are moulded from urea formaldehyde resin solution, a catalyst such as formic acid and, optionally, a foaming agent, casting the mixture in an open-topped mould, partially drying and curing the resulting gel at 20.degree. C to 70.degree. C to produce a preform, and subsequently heat-treating the preform above 120.degree. C in a restraining mould and allowing it to expand therein.

Abstract: A multilayered molded plastic having at least one layer comprising pullulan. The molded plastic is low in gas permeability, transparent, high in strength and non-toxic.

Abstract: Fire retardant polystyrene insulating material is manufactured from expandable polystyrene beads in admixture with a phenol-formaldehyde or melamine-for-maldehyde resin in resole form, the resin containing a blowing agent and a surfactant. The insulating material is formed from the bead-resin mix by applying dielectric heating to foam the resin, expand the beads, and cure the foamed resin to a closed cell structure.