Abstract: A water-dispersible mold for making a casting comprises a water-insoluble particulate material, such as foundry sand, a binder which includes polyphosphate chains and/or borate ions, and at least one fine particulate refractory material such as one selected from finely particulate silica, silicates and aluminosilicates. The incorporation of the fine particulate refractory results in improvements in the strength and related properties of the mold, when hot, prior to casting.

Abstract: An anti-fouling composition for preventing or controlling the growth of aquatic or marine organisms comprising particles of a water-soluble glass dispersed in or suspended in a hardened liquid resin composition. The water-soluble glass contains phosphorous pentoxide in an amount of 58-66% by weight and copper oxide in an amount of 8-30% by weight of the glass. The composition may be coated onto a surface intended to be exposed to, or submerged in, an aqueous environment or may be formed, by molding or casting, into an article which may be submerged in fresh or sea water.

Abstract: A water dispersible mould for making a casting, the mould comprising a water-insoluble particulate material-and a binder therefor, the binder including polyphosphate chains and/or borate ions. The invention also provides a process for making a water dispersible mould for making a casting, the process including the steps of: (a) providing a water-insoluble particulate material; (b) combining the particulate material with a binder including polyphosphate chains and/or borate ions, the chains and/or ions being dissolved in water; (c) forming, either during or after step (b), the particulate material and binder mixture into a desired shape; and (d) removing free water from the mixture. The polyphosphate chains may be derived from a water soluble phosphate glass and the borate ions may be derived from a soluble borate glass.

Abstract: A device for controllably delivering a material into an aqueous medium, the device comprising a soluble portion which is adapted, in use, to dissolve in an aqueous medium thereby to deliver into the aqueous medium a material which is retained in the device, the soluble portion comprising a soluble phosphate glass having a P.sub.2 O.sub.5 content of from 40 to 50 mole %, and constraining means which are located in the vicinity of the soluble portion and which are arranged, in use, to constrain a stationary liquid layer between the soluble portion and the constraining means. The invention also relates to a method of controllably dissolving a soluble phosphate glass in an aqueous medium.

Abstract: The invention relates to foundary moulding compositions useful for producing moulds for the manufacture of metal castings wherein the moulds are capable of giving castings with good surface finish without the need for conventional separate blacking applications. A foundary moulding composition of the invention comprises refractory material such as sand, alkali phenol-formaldehyde resole resin solution, carbonifiable material such as styrenated phenol, and an effective amount of an organic ester for hardening the composition. In another embodiment, the invention is a binder composition comprising alkali phenol-formaldehyde resole resin solution and carbonifiable material capable of being hardened by reaction with organic ester. In another embodiment, the invention is a curing additive for a foundry binder comprising carbonifiable material and liquid ester such as gamma-butyrolactone, and the like.

Abstract: The invention relates to foundry moulding compositions useful for producing moulds for the manufacture of metal castings wherein the moulds are capable of giving castings with good surface finish without the need for conventional separate blacking applications. A foundry moulding composition of the invention comprises refractory material such as sand, alkali phenol-formaldehyde resole resin solution, carbonifiable material such as styrenated phenol, and an effective amount of an organic ester for hardening the composition. In another embodiment, the invention is a binder composition comprising alkali phenol-formaldehyde resole resin solution and carbonifiable material capable of being hardened by reaction with organic ester. In another embodiment, the invention is a curing additive for a foundry binder comprising carbonifiable material and liquid ester such as gamma-butyrolactone, and the like.

Abstract: A foundry moulding composition comprising (a) a granular refractory material, and (b) from 0.5% to 8% based on the weight of the refractory material of a binder comprising (i) an aqueous solution of a potassium alkali phenol-formaldehyde resin, said aqueous solution having a solids content of from 50% to 75% and said resin having a weight average molecular weight (M.sub.w) of from 600 to 1500, a formaldehyde:phenol molar ratio of from 1.2:1 to 2.6:1 and a potassium hydroxide:phenol molar ratio of from 0.2:1 to 1.2:1 and (ii) at least one silane in an amount of from 0.05% to 3% based on the weight of said aqueous solution, said binder being curable by contact therewith of from 5% to 60% based on the weight of said aqueous solution of a C.sub.1-3 alkyl formate.

Abstract: A foundry molding composition comprising,(a) a granular refractory material;(b) about 0.8 to 5.0% of an alkaline phenolic resin based on the weight of the refractory material;(c) about 25 to 110% of a lactone based on the weight of the phenolic resin.

Abstract: A foundry moulding composition comprising (a) a granular refractory material, and (b) from 0.5% to 8% based on the weight of the refractory material of a binder comprising (i) an aqueous solution of a potassium alkali phenol-formaldehyde resin, said aqueous solution having a solids content of from 50% to 75% and said resin having a weight average molecular weight (M.sub.w) of from 600 to 1500, a formaldehyde:phenol molar ratio of from 1.2:1 to 2.6:1 and a potassium hydroxide:phenol molar ratio of from 0.2:1 to 1.2:1 and (ii) at least one silane in an amount of from 0.05% to 3% based on the weight of said aqueous solution, said binder being curable by contact therewith of from 5% to 60% based on the weight of said aqueous solution of a C.sub.1-3 alkyl formate.

Abstract: A foundry moulding composition comprising(a) a granular refractory material,(b) from 0.25 to 2.5% based on the weight of the refractory material of an aqueous solution of a potassium alkali phenol-formaldehyde resin, said aqueous solution having a solids content of from 50 to 75% and said resin having a weight average molecular weight (M.sub.wr) of from 700 to 2000, a formaldehyde:phenol molar ratio of from 1.2:1 to 2.6:1 and a potassium hydroxide:phenol molar ratio of from 0.5:1 to 1.2:1;(c) from 0.05 to 3% based on the weight of said aqueous solution, of at least one silane, and(d) from 20 to 110% based on the weight of said aqueous solution of at least one ester active to catalyze curing of said resin.