Abstract: The preparation of novolaks from phenols or mixtures of different phenols, and oxo compounds or mixtures of oxo compounds by condensation of the reactants in a medium having a low water content in homogeneous phase at temperature of .gtoreq.110.degree. C., preferably between 115.degree. and 200.degree. C. and preferably at normal pressure, in the presence of water-immiscible and/or only partially water-miscible inert organic solvents and of acids as catalysts with removal of water by distillation, the medium having a low water content being prepared or maintained by distilling off water from the reaction mixture, preferably by azeotropic distillation. Particular advantages are obtained when readily volatile oxo compounds, in particular aqueous formaldehyde solutions, are used.

Abstract: Resin solution for cements and coating compositions based on a reaction product of epoxy resins having more than one epoxy group in the molecule and furfuryl alcohol alone or in admixture with other furan derivatives dissolved in reactive diluents and process for its preparation. These resin solutions are used for preparing cements and coating compositions by mixing the resin solution immediately before use with (A) at least one filler and (B) at least one curing agent or a mixture of (A) and (B), the weight ratio of the solution to the sum of components (A) and (B) being 1:(0.5-7), preferably 1:(1-4).

Abstract: A heat exchanger, particularly a coolant evaporator, is provided that has several flat pipes that are arranged parallel to one another and are each expanded at their ends with respect to a central part and are closed off by caps. The expanded ends are provided with connecting openings so that the heat exchange medium can flow to the adjacent pipe. At least one of the caps that are provided for closing off the pipe ends is equipped with a projection extending towards the inside of the pipe and closes off at least one of the connecting openings, so that the production of a heat exchanger of identically constructed flat pipes is simplified, in that by the insertion of correponding caps that either expose the connecting openings to the adjacent pipes or not, it is easy to control the flow of the heat exchange medium inside the flat pipes.

Abstract: This invention relates to a method for the manufacture of an abrasive material by means of a synthetic binder based on a mixture of phenolic resins. The phenolic resins employed have a great stability in storage, its curing times are at most equal to but preferably shorter than those commonly used, therefore higher production speeds or substantially smaller drying installations for the same production speed may be used. The binder contains only small quantities of free formaldehyde, phenol and especially formaldehyde are released in substantially reduced quantities to the environment even when the binder is heated to elevated temperatures, including temperatures above the processing temperature. The release of these substances is also considerably reduced when the abrasive material is subsequently used.

Abstract: Mixture for the production of acid-resistant sealing materials or acid-resistant impregnating materials based on epoxy resins, resols, hardening catalysts and further customary additives, which are in the form of a cement or impregnating solution and contain, as essential constituents, (A) at least one bifunctional, low-molecular epoxy resin having an epoxide equivalent weight between 87 and 1,000, (B) at least one resol formed from at least one trifunctional phenol and formaldehyde in a molar ratio of 1:1 to 1:3, having a viscosity between 50 and 2,500 mPa.s at 20.degree. C. and having a solids content of at least 50% by weight, and (C) hardening catalysts, cements also containing (D) fillers, in addition, and a process for the preparation of hardening products from the compounds. Thus, for example, cements or impervious, initially porous shaped articles which are resistant to solvents and weak acids and which have a low shrinkage after processing, are obtained.

Abstract: A cartridge for purifying exhaust gases from the internal combustion engine of an automotive vehicle or some other source comprising a catalyst support matrix wound of metal foil and a metal jacket housing said support matrix wherein a press fit exists between the exterior of the support matrix and the interior surface of the jacket and the support matrix and the jacket are welded or brazed together within the area of the press fit. Processes and apparatus for producing the cartridge of the invention are also disclosed.

Abstract: Contact adhesives based on polyurethane rubber, in which the rubber solution is combined with 2.5 to 100% by weight, based on the solid rubber, of a phenolate of titanium, zirconium and/or preferably aluminum and optionally hydroxyl group-containing compounds, and their use for bonding organic or inorganic material such as leather, polyvinyl chloride, rubber, textiles, polyurethane or glass.

Abstract: Binders based on co-condensates of epoxy resins and resols with amines, the epoxy resin being partially defunctionalized and still containing on average 0.5-1.3 epoxide groups per molecular unit, the resol component being composed of methylol compounds of oligomethylene compounds, which are additionally substituted by hydrocarbon or hydroxyalkyl or hydroxyaralkyl radicals, and the amine containing at least one primary or secondary amino group and at most 2 hydroxyl groups.The invention further relates to a process for the preparation of a binder and for the electrophoretic deposition of a cationic resin from an aqueous dispersion onto an article connected as the cathode and to an aqueous electrophoresis bath for carrying out this process.

Abstract: A method is disclosed for clamping together a first and a second part, the first part having a flange thereon, the second part having a groove which may receive the flange. The method includes the steps of placing a deformable seal on the bottom of the groove of the second part, placing the flange of the first part on the deformable seal as the flange is guided into the groove, clamping the first and second parts together while deforming the seal until the seal approximately fills a space defined between a lower surface of the flange and the walls forming the groove, and deforming certain parts of a vertically upright standing area of the second part by rolling the certain parts of the area over an upper surface of the flange into generally horizontal positions while leaving other parts of the area generally in their vertically upright condition to thereby form an approximately corrugated edge on the second part, which holds the first and second parts together in a clamped condition.

Abstract: A cartridge for purifying exhaust gases from the internal combustion engine of an automotive vehicle or some other source comprising a catalyst support matrix wound of metal foil and a metal jacket housing said support matrix wherein a press fit exists between the exterior of the support matrix and the interior surface of the jacket and the support matrix and the jacket are welded or brazed together within the area of the press fit. Processes and apparatus for producing the cartridge of the invention are also disclosed.

Abstract: A clamping connection for clamping two parts together. One part includes a flange and the other includes a deformable edge. When the parts are in their clamped condition, the edge has been deformed into a continuously corrugated configuration including alternate deformed and undeformed partial areas. The deformed partial areas positively and lockingly engage the flange when the flange and edge are in the locked condition. Thus, a positive joint is formed. The undeformed partial areas of the edge contribute to stiffening the clamping connection.

Abstract: A process for the preparation of synthetic resins based on resorcinol compounds which comprises reacting a resorcinol pitch which is obtained in the manufacture of resorcinol from benzenedisulfonic acid in at least one step with an oxo-compound selected from aldehydes, ketones and compounds based on or splitting off at least one of these substances, and the use of the products as binders for abrasive articles.

Abstract: Disclosed is a clamped connection for clamping together separate parts, comprising a first part having a flange; a second part having an edge and an edge region adjacent to the edge. The edge region is deformable from a first condition in which the edge region is continuous and straight or has a constant radius of curvature along most of its length and a second condition in which the edge region has a continuously corrugated configuration including alternately deformed and undeformed partial edge region areas. The edge region includes a plurality of elongated apertures spaced from the edge and extending generally parallel thereto, and the deformed partial edge region areas are bounded on the side opposite to the edge by these apertures, whereas the undeformed partial edge region areas are located between said apertures. Also disclosed is a device for clamping together two parts to produce the disclosed connection.

Abstract: An acid-hardening low shrinkage cement based on a furan-modified phenolic resin containing as a binder(A) a reaction product of furfuryl alcohol with a hydroxymethyl group-containing substituted phenol resol, based on a substituted phenol selected from the group consisting of bifunctional alkylphenol, an aralkylphenol each having 3 to 20 carbon atoms in the alkyl radical, an arylphenol or a combination thereof with a minor amount of one or more unsubstituted phenols, wherein in the substituted phenol resol at least 75% of the reactive H-atoms of the nucleus are substituted by reaction with formaldehyde and wherein more than 0.5 mol of furfuryl alcohol has been reacted per hydroxymethyl group; together with(B) at least one reactive diluent in a weight ratio of (B):(A) in the range from (0.4 to 1.5):1, anda process for the preparation of said composition.

Abstract: Process for the manufacture of an abrasive material comprising at least two binder layers formed from at least one aqueous resol I prepared from a monohydric phenol and formaldehyde (molar ratio of phenol to formaldehyde 1:(1.1 to 2.

Abstract: A cartridge for purifying exhaust gases from the internal combustion engine of an automotive vehicle or some other source comprising a catalyst support matrix wound of metal foil and a metal jacket housing said support matrix wherein a press fit exists between the exterior of the support matrix and the interior surface of the jacket and the support matrix and the jacket are welded or brazed together within the area of the press fit. Processes and apparatus for producing the cartridge of the invention are also disclosed.

Abstract: A synthetic resin binder comprising an aqueous mixture of phenolic resins and optionally other additives wherein the mixture of phenolic resins comprises (I) at least one phenol-resol and (II) at least one co-condensate of at least one monohydric phenol and at least one polyhydric phenol with formaldehyde and wherein in component (II) the molar ratio of the quantities of formaldehyde used to the sum of phenols is within the range of from 0.6:1 to 1.5:1, a method for the manufacture of an abrasive by means of said synthetic resin binder and the abrasives itself.

Abstract: A rubber composition having improved tackiness and comprising a natural or synthetic rubber and as a tackifier from 0.3 to 15% by weight (referred to the rubber) of a modified alkylphenol novolak prepared from(A) a phenol component selected from the group consisting of(i) a monoalkylphenol having from 3 to 18 carbon atoms in the alkyl group, and(ii) a mixture of (i) with up to 30 mol% of a dialkylphenol having a total of from 6 to 24 carbon atoms in the alkyl groups with(B) a substance which is at least trifunctional with respect to formaldehyde and(C) formaldehydeWherein the molar ratio of one of components (i) and (ii): (B) is from 70:30 to 99:1, a method for its preparation and a molded article prepared therefrom.

Abstract: A process for hardening (I) a resin which is the reaction Product of a first reaction of a) an epoxy resin which contains at least two epoxy groups with b) an olefinically unsaturated monocarboxylic acid followed by a reaction with c) a carboxylic groups containing component; by copolymerizing said resin (I) with (II) a copolymerizable unsaturated monomer under the action of irradiation of an electron beam, one polycarboxylic acid unit of said carboxylic groups containing component being attached to at least two molecules of the epoxy resin the number of epoxy groups being approximately equal to the sum of the number of free carboxylic groups and the number of anhydride groups, the proportion being 1.25 to 1.5 equivalents of epoxyde per equivalent of unsaturated monocarboxylic acid and about 0.25 to 0.5 mol of carboxylic groups containing compound. The radiation dose may be as low as 0.25 Mrad/g resin. Shaped body which is obtained by the process and which may be a film, fibre or a coating.

Abstract: A process for preparing abrasives which comprises coating a fibrous substrate with a binder comprising a hardenable resin and subsequently curing the binder coat by electron irradiation. The radiation dose may have an energy of from 175,000 to 1,000,000 eV and a dose of from 0.5 to 30 Mrad. An abrasive which is obtained by the process and which is water resistant.