Abstract: A molding material mixture for producing casting molds for metal processing, particularly for non-ferrous metals, such as aluminum or magnesium, is intended to reduce problems such as metal-mold reaction and/or shrinkage porosity defect. The free-flowing refractory molding material in the molding material mixture is coated with a mixture of inorganic salts exhibiting a eutectic melting point in the range of about 400 C to about 500 C, particularly in the range of about 420 C to about 460 C. Preferably this coating occurs by contacting the inorganic salt mixture with the molding material mixture at a temperature between 500 C and 700 C, in a manner that maintains the free-flowing nature of the coated product. One mixture of inorganic salts that is used is a mixture consisting of, by weight: 74% potassium fluoroborate; 15% potassium chloride; and 12% potassium fluoride. This mixture has a eutectic melting point of 420 C.

Abstract: A molding material mixture for producing casting molds for metal processing, particularly for non-ferrous metals, such as aluminum or magnesium, is intended to reduce problems such as metal-mold reaction and/or shrinkage porosity defect. The free-flowing refractory molding material in the molding material mixture is coated with a mixture of inorganic salts exhibiting a eutectic melting point in the range of about 400 C to about 500 C, particularly in the range of about 420 C to about 460 C. Preferably this coating occurs by contacting the inorganic salt mixture with the molding material mixture at a temperature between 500 C and 700 C, in a manner that maintains the free-flowing nature of the coated product. One mixture of inorganic salts that is used is a mixture consisting of, by weight: 74% potassium fluoroborate; 15% potassium chloride; and 12% potassium fluoride. This mixture has a eutectic melting point of 420 C.

Abstract: A “no-bake” process allows the forming of larger metal castings, by providing longer work times, in the range of about 45 to about 60 minutes. This is achieved using a liquid curing catalyst that is a pyridine, substituted at the second or third position with a moiety having a molecular weight in the range of about 30 to about 100 mwu. Examples of the liquid curing catalyst include 2-ethanolpyridine, 3-chloropyridine and 2-methoxypyridine. When combined with a two-part polyurethane binder precursor and a foundry aggregate, the liquid curing catalyst provides not only the longer work time, but also a strip time that is less than about 167% of the work time, as measured from the point of activating the polyurethane precursors by mixing them in the presence of the curing catalyst.

Abstract: A “no-bake” process allows the forming of larger metal castings, by providing longer work times, in the range of about 45 to about 60 minutes. This is achieved using a liquid curing catalyst that is a pyridine, substituted at the second or third position with a moiety having a molecular weight in the range of about 30 to about 100 mwu. Examples of the liquid curing catalyst include 2-ethanolpyridine, 3-chloropyridine and 2-methoxypyridine. When combined with a two-part polyurethane binder precursor and a foundry aggregate, the liquid curing catalyst provides not only the longer work time, but also a strip time that is less than about 167% of the work time, as measured from the point of activating the polyurethane precursors by mixing them in the presence of the curing catalyst.

Abstract: A furfuryl alcohol derivative having the general formula X[—CH(OR)2]m is prepared by an aldehyde with a furfuryl alcohol in the presence of a copper catalyst. In this formula, X is an aliphatic, cycloaliphatic, aromatic or araliphatic group, R is a 2-furyl group, 2-(5-methylol) furyl group or a mixture thereof, and m is in the range of from 1 to 5. Reaction conditions allow a product having less than 25% free furfuryl alcohol, providing a composition that is suitable as a binder for foundry aggregate in producing a foundry mix.

Abstract: Disclosed is a method for making metal castings wherein a composite core assembly is utilized. The composite core assembly comprises at least one casting core and one temporary core which are in intimate contact wherein the temporary core is removed prior to casting. The improvement of the present invention comprises forming the temporary core comprising an aggregate and binder of materials such that the temporary core is sufficiently soluble in aqueous solvent for its removal prior to metal casting. The casting core is not removed by the aqueous solvent.

Abstract: Disclosed is a process for recovering a virtually water-free amine from an amine acid salt thereof. The process comprises a unique combination of phase separation stages practiced under mild heating and distillation stages. An amine product containing less than 0.2% water can be achieved by the present process. The feedstock for the process suitably is an acid scrub liquor used to scrub amine from a vapor stream thereof which has been used in a cold-box molding process in the foundry industry or in the cure of vapor permeation curable coatings in the coatings industry.

Abstract: Disclosed is a process for recovering a virtually water-free amine from an amine acid salt thereof. The process comprises a unique combination of phase separation stages practiced under mild heating and distillation stages. An amine product containing less than 0.2% water can be achieved by the present process. The feedstock for the process suitably is an acid scrub liquor used to scrub amine from a vapor stream thereof which has been used in a cold-box molding process in the foundry industry or in the cure of vapor permeation curable coatings in the coatings industry.

Abstract: Foundry cores and molds for casting metals are prepared by forming a binder comprising a polyol, an isocyanato urethane polymer and a urethane catalyst. The foundry cores and molds of this invention are formed by processes known in the industry as the "cold box" process and the no-bake process. The binder is especially useful for casting non-ferrous metals, for example, the casting of aluminum, magnesium and other lightweight metals. The cores and molds produced for casting aluminum and other lightweight metals exhibit excellent shakeout while retaining other desirable core and mold properties.