A heat-insulating material comprising from 85 to 98 parts by weight of mineral wool and from 15 to 2 parts by weight of a binder applied onto the wool, which is a modified resol phenol-formaldehyde resin on the basis of phenol, formaldehyde, sodium hydroxide, a water proofing additive which is an individual alkylresorcinol with a number of side chain carbons of 2 to 8 or a mixture of alkylresorcinols, as well as urea, or dicyandiamide, or melamine, the ratio between said components being as follows (parts by weight): The proposed heat-insulating material features improved adhesion properties, has a reduced water absorption and an increased moisture resistance.
A sizing composition which is a phenol-formaldehyde resin substantially free of urea or of a urea derivative and which has reduced emissions of isocyanates upon heating. Insulation products based on mineral wool, especially glass wool or rock wool, which are suitable for mass-produced thermal appliances and contain the sizing composition have reduced organic emissions during manufacturing and when used in thermal appliances.
Equipment for testing or test sampling liquid metal by introducing a protection sleeve (3; 3'; 3") together with a testing or sampling means (2; 11) provided inside the protection sleeve. The protection sleeve comprises a thermoinsulating tube (3; 3'; 3") made of synthetic amorphous mineral fibers, preferably fibres of diabase type and having a sagging point of 1,000.degree.-1,200.degree. C. according to the standards of the Swedish Institute for Materials Testing, and bound with an evenly distributed binder comprising or including among other things a binder component of organic type, for instance a thermosetting resin like phenol resin, carbamide resin or melamine resin and/or substances incorporated in the fiber material, for instance crystal water containing salts or carbonates which at the temperature of the liquid metal spontaneously and successively emit gases. The mineral fibre tube (3; 3'; 3") can be manufactured from mineral fibres having an original weight per unit of volume of 20-70 kg/m3, which have been compressed to a weight per unit of volume of 200-800 or preferably 500-700 kg/m3. Preferably the binder is added in an amount of 2-8 % by weight. The intensity of the turbulent flow in the molten metal is controlled by varying the amount of binder in the thermoinsulating mineral fibre tube and/or by varying the hardness of the mineral fibre tube.
A thermal insulating body or shape is made up of highly dispersed insulating material together with mineral fiber wool and of opacifier together with a binder for curing. The binder, which is evenly distributed in a first-stage mix with a dispersant, is present in a finely dispersed condition in the insulating material, the corners and edges of the insulating material being able to undergo cross-linking with the binder by heat processing.
This invention relates to an organic foundry binder containing an alkyl resorcinol, or preferably a readily available mixture of alkyl resorcinols, and derivatives thereof. Preferably, the organic foundry binder is a furan binder. Foundry mixes are prepared by mixing the binder with a foundry aggregate. Foundry shapes (molds and cores) are prepared by shaping the mix and allowing it to cure to form a workable foundry shape. The invention also relates to the preparation of metal castings using the foundry shapes and the metal castings prepared with the foundry shapes.
This invention is to disclose an insulated heated sprue bushing in plastic molding apparatus, and comprises a plastic molded segment as a thermal barrier to insulate or break the heat flow between the sprue bushing shoulder and neck section of the stem of the sprue bushing, and a heater band placed on the head of the sprue bushing.
