Abstract: The inventive concept is to condense the phenol formaldehyde resins to a higher molecular weight than usual so far. Subsequent addition of urea thereto reduces viscosity to normal levels and increases solid content.The added urea does not take part in condensation reaction but partly reacts in the alkaline medium with formaldehyde to methylol urea (in a so called equilibrium reaction), which is formaldehyde donor for the phenol formaldehyde crosslinking reaction during the pressing of the particle board.The present invention relates to a process for producing modified phenolic resin bonding agents, characterized by preparing as known per se phenol-formaldehyde resins with a viscosity of more than 300 mPa.s (at 20.degree. C.

Abstract: A binder composition for producing articles of bonded particulate material such as foundry moulds or cores comprises an alkaline aqueous solution of a resol phenol-aldehyde resin and an oxyanion capable of forming a stable complex with the resin the amount of alkali present in the solution being sufficient to substantially prevent stable complex formation. Bonded articles are produced from mixtures of particulate material and the binder composition by passing carbon dioxide gas through the formed articles whereby the oxyanion forms a stable complex with the resin and the resin is cured. The oxyanion may be for example borate, stannate or aluminate.

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 binder composition for producing articles of bonded particulate material such as foundry moulds or cones comprises an alkaline aqueous solution of a resol phenol-aldehyde resin and an oxyanion capable of forming a stable complex with the resin the amount of alkali present in the solution being sufficient to substantially prevent stable complex formation. Bonded articles are produced from mixtures of particulate material and the binder composition by passing carbon dioxide gas through the formed articles whereby the oxyanion forms a stable complex with the resin and the resin is cured. The oxyanion may be for example borate, stannate or aluminate.

Abstract: The titled compositions are useful binding adhesives, especially, for example, with engineered glass fiber-containing products, and the like. In the A-stage, the compositions are typically exceptionally water soluble and low temperature storage stable. Such compositions can be prepared initially by a procedure in which a resole or the like is copolymerized with free melamine(s) and is conditioned to include acidic stage conditioning. For example, phenol per se, formaldehyde and sodium hydroxide followed by melamine per se and aqueous sulfamic acid solution, with subsequent neutralization, can yield the exceptionally water soluble low temperature storage stable A-stage composition. The C-stage composition is non-punking and can be structurally hard and sound.

Abstract: The invention relates to the use of lithium ion-generating alkalizing agents in resole binder compositions useful for bonding aggregate materials to form refractory articles. Use of lithium-ion generating alkalizing agents produce resole resin binder compositions which, when cured by an ester functional curing agent, exhibit tensile and compression strengths superior to strengths obtained from compositions using sodium ion-generating or potassium ion-generating alkalizing agents.

Abstract: The binder serves to produce foundry moulds and comprises a solution (preferably an aqueous solution) of aldehyde reactive phenol substances and gaseous acetals (preferably dimethyl formal) as reaction partners and strong acids, e.g. sulphuric acid and sulphonic acids as a catalyst. The acetal is in this system hydrolysed by the acid, the basic aldehyde being formed, which will react with the aldehyde reactive phenol substance accompanied by cross-linking. The acid serves thereby simultaneously as a cross-linking catalyst. In principle, it is possible to regard as "aldehyde reactive phenol substances" any phenolic compounds which can in the acid range cross-link more or less spontaneously with aldehydes. Preferably, these are resorcinol or resorcinol products, e.g. resorcinol pitch or precondensates formed with a shortfall of aldehyde, e.g. based on resorcinol formaldehyde, phenol resorcinol formaldehyde or resorcinol melamine formaldehyde.To produce foundry moulds, a granular basic moulding material, e.g.

Abstract: A water-based coating composition comprising as the first component, a mixture of a polyaldehyde chosen from the group consisting of glyoxal, glutaraldehyde and derivatives of glyoxal and glutaraldehyde, and a water dispersible component chosen from the group consisting of epoxy resin emulsions which can be emulsified in water, synthetic latexes stable at about pH 7 or less, low molecular weight resin emulsions, epoxy ester emulsions, water emulsified alkyds, and cationic, anionic and non-ionic asphalt emulsions and, as the second component, the non-gel reaction product of (I) urea-formaldehyde ether monomer, urea-formaldehyde phenol monomer, urea-nonylphenol formaldehyde monomer, thiourea-formaldehyde ether monomer, melamine formaldehyde ether monomer hexamethoxymethyl melamine, with (II) a polyamine chosen from a group consisting of primary and secondary amines and/or a monoamine, combined with (III) a hydroxide or oxide of calcium, strontium or barium.

Abstract: A flexible fibrous reinforced phenol-formaldehyde sheet molding compound capable of rapid curing to an infusible state.

Abstract: An adhesive paste for adhering two or more objects, a composite assembly comprising two or more elements bonded by such paste, and a process for preparing cast metal articles using such paste are provided. The adhesive paste comprises an aqueous solution of a specific alkali phenol-formaldehyde resin and a hardener for that resin, wherein the paste prepared by mixing the resin and hardener has a viscosity, as mixed, in the range of about 1,000 cps to about 15,000 cps. The composite assembly comprises at least two separate elements bonded by the adhesive paste of the invention. The process uses a mold or core assembly having at least two separate elements.

Abstract: Particulate novolac resins and aqueous dispersions are produced by condensing phenol with aldehyde using acid catalysis. Following neutralization, particulate novolac resin is formed by adding protective colloid to the aqueous mixture. Resin particle isolation can be aided by dephenolation.

Abstract: A water soluble phenolic resole-urea composition useful as a binder which remains infinitely water-dilutable and free of sediment after one month of storage at 0.degree. C. and is made by the reaction of urea with the free formaldehyde in a phenolic resole under acid conditions, followed by the further addition of urea at neutral or slightly basic conditions.

Abstract: A process for producing microspherical cured phenolic resin particles having a particle diameter of not more than about 100 .mu.m, which comprises reacting a novolak resin, a phenol and an aldehyde in an aqueous medium in the presence of a basic catalyst and an emulsion stabilizer. Novel microspherical cured phenolic resin particles are produced by this process. The resin particles have excellent impact strength and mechanical properties, a sharp particle size distribution, and a low secondary agglomerate content, and because of these properties, are useful as an excellent modifier or filler for various plastics and rubbers.

Abstract: The invention provides a method for the enhanced recovery of oil from an oil-bearing stratum having a zone of high fluid permeability through plugging of this zone by introducing into the stratum a gelable solution which, in the case of use under moderately high operating temperatures in the stratum, comprises a polyphenolic lignin extract, a formaldehyde source and sufficient alkaline material to give a solution having a pH of at least 9.0 and which, in the case of higher operating temperatures, comprises a lignosulfonate and a source of formaldehyde or tannin in aqueous solution.

Abstract: What is disclosed are aqueous compositions which are useful for coating solid substrates such as glass, plastic and metal. The aqueous compositions comprise colloidal silica, a phenolic resin, water and at least one hydrolyzable silane. An example of such a composition is colloidal silica, phenolic resin, water and CH.sub.3 SiO.sub.3/2 obtained from CH.sub.3 Si(OCH.sub.3).sub.3.

Abstract: A condensation product of phenol, formaldehyde and urea condensed in the presence of a basic catalyst, said condensation product being a liquid and having a free phenol content below 0.5%, a free formaldehyde content below 3%, expressed by weight based on the total weight of liquid, and a dilutability, measured at 20.degree. C., of at least equal to 1000%.

Abstract: Compositions and methods are used for reducing the permeability of high fluid permeability segments of underground strata, the compositions being injected into the high permeability segments in liquid form and there gelled to reduce the permeability of the segments. A first group of compositions has a pH of at least 4 and comprises a sulfited derivative of a tannin extract together with furfural, formaldehyde or a formaldehyde derivative. The second group of compositions comprises furfural and a gellable vegetable material which can be a tannin extract, a sulfited derivative of a tannin extract, a catechin, an alkaline extract of a coniferous bark or a lignin or sulfonated lignin derivative.

Abstract: A condensation product of phenol, formaldehyde and urea condensed in the presence of a basic catalyst, said condensation product being a liquid and having a free phenol content below 0.5%, a free formaldehyde content below 3%, expressed by weight based on the total weight of liquid, and a dilutability, measured at 20.degree. C., of at least equal to 1000%.

Abstract: An improved moisture-stable phenolic resin binder with calcium ions from the catalyst complexed with the phenolic resin and a process for its preparation and laminate boards with the said binder as the binding agent.

Abstract: An improved process for the production of glass and mineral fiber products bonded with a phenolic resin in which an aqueous phenol-formaldehyde resin is applied to the inorganic fiber as the bonding agent which is formed with calcium hydroxide as condensation catalyst and the mixture is thermally cured, the improvement comprising prior to processing the aqueous phenol-formaldehyde resin is adjusted to a pH of 7.5 to 11 by addition of a base and sulfate ions are added in an amount of 80 to 200% of the stoichiometric amount required for bonding the calcium ions whereby the calcium ions are converted into a water-soluble complex stable for at least three hours without any precipitation and the products produced thereby.

Abstract: There is provided a method for preparing cured moulded article of a predetermined density of from 1.66 to 9.0 which comprises selecting the resin and determining it % weight loss and % porosity under the curing conditions for the selected resin, then selecting a high density filler and a low density filler and resolving the equation: ##EQU1## wherein K is the desired density of the end product and has a value of from 1.66 to 9.0; HD is the density of the selected high density substantially water-insoluble material and has a value of above 3.2; ID is the density of the selected medium density substantially water-insoluble material and has a value of from 1.5 to 3.2; R is the density of the cured binding resin and has a value between 0.8 to 1.

Abstract: Novel metal-modified phenolic resins useful in the color developer part of a carbonless copy paper system are disclosed, as well as methods for preparing such resins. The metal-modified phenolic resins are reaction products of an aromatic carboxylic acid and a partial condensation reaction product (an oligomer) of a phenol and an aldehyde. The metal-containing compound is added either to the mixture of phenol and aldehyde in forming the oligomer or to the mixture of aromatic carboxylic acid and the oligomer. The color developer materials of the invention are coated on a paper substrate which forms a part of a pressure sensitive recording paper system. The color developer materials exhibit improved performance over prior art colored developer materials.

Abstract: A phenol-resorcinol-formaldehyde resin and a method for making the same. In this method phenol and formaldehyde at an initial pH of 8.5 to 9.2 are reacted in the presence of a sodium sulfite catalyst. The reaction mixture is heated and refluxed until it has a viscosity of u-v on the Gardner bubble test. Additional resorcinol is added to the mixture and refluxing is continued until it has a viscosity of 30 to 100 Garner sections. The reaction mixture is diluted with a water miscible solvent to obtain a resin solution having a solids content of about 40 to 60 percent by weight and a viscosity of 2.0 to 3.5 poise. An alkali metal carbonate material in the amount of 4 to 8 percent by weight of the resin is added to make adhesives including this resin fast curing. Fumed silica is also added to the resin solution by means of high shear apparatus to make the solution thixotropic.

Abstract: Binders are described based on acid curing phenol resins and acid curing agents which, after mixing, have an extended processability time but nevertheless exhibit a rapid curing time at relatively low temperatures. They are obtained by using, as the resin, aqueous phenol resols and, as the curing agent, either copper, aluminum, or iron(III) salts of aromatic sulfonic acids or addition products of hydroxy-containing, water-compatible polyols with aromatic sulfonic acids or mixtures of these salts and the polyol addition products. The binders are used for impregnation of fabrics, for production of abrasives and for fiber reinforced plastics.

Abstract: What is disclosed are aqueous compositions which are useful for coating solid substrates such as glass, plastic and metal. The aqueous compositions comprise colloidal silica, a phenolic resin, water and at least one hydrolyzable silane. An example of such a composition is colloidal silica, phenolic resin, water and CH.sub.3 SiO.sub.3/2 obtained from CH.sub.3 Si(OCH.sub.3).sub.3.

Abstract: Water-dilutable resinous products are obtained by reacting(A) a resin having at least one phenolic hydroxyl group and a free position ortho and/or para to a phenolic hydroxyl group, and containing a residue formed by polymerization of a vinyl monomer in the resin or in a precursor thereof,(B) an aldehyde, and(C) sulphurous acid or an organic acid containing a primary or secondary amino group or a mercaptan group and a carboxylic, sulphonic or phosphonic acid group, or a water-soluble salt thereof.Aqueous compositions containing the resinous products and, if required, and aminoplast, a phenoplast or a blocked polyisocyanate, usually together with a minor amount of an organic solvent, are useful in the formation of surface coatings.

Abstract: Coating of a resin blend on a metal substrate by electrodeposition wherein the resin blend comprises a poly(3,4-dihydro-3-substituted-1,3-benzoxazine) and a reactive polyamine. The resin blend is dispersed in an aqueous medium containing a protonating acid and is subjected to cathodic electrophoresis to deposit the blend on a metal substrate as an adherent film which is dried and cured by the application of heat. The resin blend cures at relatively low temperatures without evolution of volatile matter.

Abstract: An aqueous dispersion comprising a poly(3,4-dihydro-3-substituted-1,3 benzoxazine) and a protonated reactive polyamine, wherein the polyamine is at least difunctional, its reactive groups being primary or secondary amine and is protonated with an inorganic or organic acid and wherein the poly(dihydrobenzoxazine) is the reaction product of about 1 equivalent of a primary amine, about 1 equivalent of a phenol and about two equivalents of formaldehyde. The dispersions can be dried and cured to provide useful surface coatings and primers. The curing step occurs without evolution of volatile matter.

Abstract: A suspension or solution containing an acid-curable fluoride-containing resin which is useful in a foundry process is disclosed. The fluoride-containing resin is curable at room temperatures and above by the addition of a strong acid catalyst. The resin is preferably a phenolic resole resin or a furan-type resin. The fluoride-containing resins, when used in a foundry process are preferably admixed with a foundry sand and a strong acid catalyst. The coated sand is then shaped into the form of a foundry core and is allowed to cure at room temperature or above to a foundry core having excellent tensile strength.

Abstract: A phenol-formaldehyde resol to which urea has been added is mixed with a boric acid-hydroxyl-amide component to provide high temperature resistant binder compositions for use in the manufacture of thermally stable bonded mineral fibre insulation structures.

Abstract: A method of preparing a thermoplastic, water-soluble, phenolic aldehyde resin and the composition are provided to enhance the flexibility and resistance to compression fatigue breakage of glass fibers to which the resin has been applied. The method involves two steps. In the first step, the phenolic compound and the aldehyde are reacted to less than 100 percent completion in an amount so that the aldehyde to phenolic compound ratio is in the range of about 0.6 to about 1.5 and at an acidic pH and for a period of time equivalent to about 3 hours to about 10 hours when the temperature is in the range of about 55.degree. F. (13.degree. C.) to about 90.degree. F. (32.degree. C.) to produce a resinous mixture. In the second stage the pH of the reaction is adjusted within the range above about 7.0 to about 7.

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.

Abstract: An ink composition for use in ink-jet printing to print images on a substrate, the composition being formulated to include, as the resin component, a phenolic resole resin and, as the primary solvent, a lower alkanol. The composition is also formulated to contain a pigment or soluble basic dye, a resistivity control agent preferably in the form of hydroxylamine hydrochloride, an evaporation retardant, and a modifying resin. The use of a phenolic resole resin which is capable of undergoing cure on evaporation of the solvent provides a printed image having improved adherence to various printing substrates and can be formulated and dissolved in less toxic, lower alkanol solvents.

Abstract: A method of preparing a thermoplastic, water-soluble, phenolic aldehyde resin and the composition are provided to enhance the flexibility and resistance to compression fatigue breakage of glass fibers to which the resin has been applied. The method involves two steps. In the first step, the phenolic compound and the aldehyde are reacted to less than 100 percent completion in an amount so that the aldehyde to phenolic compound ratio is in the range of about 0.6 to about 1.5 and at an acidic pH and for a period of time equivalent to about 3 hours to about 10 hours when the temperature is in the range of about 55.degree. F. (13.degree. C.) to about 90.degree. F. (32.degree. C.) to produce a resinous mixture. In the second stage the pH of the reaction is adjusted within the range above about 7.0 to about 7.

Abstract: An aqueous solution of a resin glue comprising formaldehyde, urea, melamine and phenol is obtained when phenol, formaldehyde and not more than 0.35 mole of an alkali metal bisulfite per mole of phenol are reacted to give a phenol-formaldehyde condensate, formaldehyde and urea in a molar ratio of not more than 2.5 are reacted to give a urea-formaldehyde condensate, and the reaction products are in turn reacted with melamine and formaldehyde.

Abstract: A bath composition for cataphoretic electrocoating of conductive surfaces contains coating agents which have been rendered soluble or dispersible with acid, contain basic nitrogen groups and carry groups of the general formulae (1) and (11) ##STR1## and, optionally, also groups of the general formulae (III) and/or (IV) ##STR2## where R.sup.1 and R.sup.2 are each alkyl, hydroxyalkyl or alkoxyalkyl, R.sup.3 and R.sup.4 are each hydrogen or methyl, R.sup.5 and R.sup.6 are each hydrogen, alkyl or a divalent radical of a polymer molecule which is bonded to a phenol or phenol ether, n.sup.1 is 1, 2 or 3 and n.sup.2 is 1 or 2, and where the oxygen bonded to the phenyl radical is either in the form of the OH group or etherified.

Abstract: The invention is an improved hardener for use with phenolresorcinol-formaldehyde wood bonding adhesives. The hardener is conveniently made and shipped as a stable dry powdered material. It is then slurried in water at the point of use for convenience with continuously mixed and dispensed liquid-liquid, two part adhesive systems. The hardener comprises paraformaldehyde or alphapolyoxymethylene, fillers, viscosity and/or rheology control agents, and a solid acidic material. The latter ingredient is a critical component used to adjust the pH of an aqueous slurry to the range of 4.0 to 5.5. Oxalic acid is preferred. In this pH range, the formaldehyde polymers are stable and the slurried hardener does not give off significant formaldehyde odor for periods up to several days. Bonding performance is improved because the characteristics of the hardener and resulting adhesive have very little variation over time.

Abstract: An adhesive having a high adhesive strength and capable of bonding firmly polyester fibrous material with rubber is disclosed, which comprises a mixture of components A and B in a mixing ratio of A/B of 100/5-100/30, said component A being formaldehyde condensate obtained by reacting formaldehyde with one member selected from the following members (1)-(4): (1) a mixture of resorcin with one of m-cresol, m-methoxyphenol, 3,5-xylenol and m-xylene, (2) a mixture of 5-methylresorcin with m-cresol or with m-methoxyphenol, (3) a mixture of m-cresol with p-chlorophenol and (4) m-cresol, and having substantially an average molecular weight of 300-600; and said component B being one member selected from the following members (5)-(7); (5) a formaldehyde condensate obtained by reacting formaldehyde with one of 3,5-xylenol, m-t-butylphenol and a mixture of m-cresol with m-t-butylphenol and having substantially an average molecular weight of 200-500, (6) 4,4'-thio-bis(6-t-butyl-3-methylphenol) and (7) 1,1'-bis(2,4-dihydro

Abstract: A process for preparing a urea-formaldehyde base resin having a F/U molar ratio of 1.0:1-1.2:1, that is hydrolytically stable, which comprises adjusting a formaldehyde solution to a pH of 0.5-2.5, slowly charging urea to said formaldehyde solution while maintaining the temperature at 40.degree.-70.degree. C., neutralizing the reaction mixture after obtaining a Gardner viscosity in the range of T+-V+, then adding the final charge of urea and permitting equilibration.

Abstract: A process for bonding lignocellulosic material under heat and pressure, where the bonded lignocellulosic material is characterized by a low emission of formaldehyde, which comprises applying a binder to said lignocellulosic material, said binder comprising a urea-formaldehyde base resin having a ratio of formaldehyde to urea of 1.0:1-1.2:1, said base resin having essentially no free formaldehyde and said base resin when cured containing substantially more methylene groups than methylene ether groups, consolidating said lignocellulosic material and curing the binder.

Abstract: Water-repellent adhesive composition for wooden material which consists essentially of a paraffin emulsion and a resin material selected from the group consisting of urea resin, urea-melamine resin, and phenol resin, wherein said paraffin emulsion contains oxidized paraffin.

Abstract: An amine resin soluble in water with the aid of an acid is produced by reacting a dihydric phenolic compound, such as a bisphenol, with a stoichiometric deficiency of preferably aromatic diepoxide, and then reacting the product containing less than -0.3 part of unreacted dihydric phenolic compound per part of reaction product with at least about 3.25 mol of formaldehyde per mol of said reaction product and with monosecondary amine to produce a Mannich base. This Mannich base is then reacted with additional diepoxide in an amount of from 0.5 to 2 epoxy equivalents per epoxy equivalent in the initially used diepoxide.

Abstract: A method of preparing a thermoplastic, water-soluble, phenolic aldehyde resin and the composition are provided to enhance the flexibility and resistance to compression fatigue breakage of glass fibers to which the resin has been applied. The method involves two steps. In the first step, the phenolic compound and the aldehyde are reacted to less than 100 percent completion in an amount so that the aldehyde to phenolic compound ratio is in the range of about 0.6 to about 1.5 and at an acidic pH and for a period of time equivalent to about 3 hours to about 10 hours when the temperature is in the range of about 55.degree. F. (13.degree. C.) to about 90.degree. F. (32.degree. C.) to produce a resinous mixture. In the second stage the pH of the reaction is adjusted within the range above about 7.0 to about 7.

Abstract: A water-base well drilling, workover or completion fluid containing a fluid loss control agent prepared by pre-reacting sulfonated phenol with formaldehyde under alkaline conditions and then reacting the mixture with phenol under controlled conditions is described.

Abstract: A stable polyol-alkali metal silicate emulsion is produced by mixing an aqueous solution of an alkali metal silicate or alkali metal metasilicate pentahydrate, a liquid polyol and a small amount of a salt of an alkali metal compound and a weak acid while heating the mixture to between 40.degree. C. and 100.degree. C. and agitating until the mixture emulsifies.

Abstract: Phenol-formaldehyde and phenol-resorcinol-formaldehyde resinous aqueous syrups useful as thermosetting binders or adhesives are prepared by reacting, a phenol-formaldehyde resin composition firstly at atmospheric reflux temperature at a substantially neutral pH of 5.8 to 8.5 and a formaldehyde to phenol mol ratio between 1.7 to 2.8 for a period of 20 to 120 minutes; reacting secondly with added formaldehyde, if necessary, and also needed alkali metal hydroxide to produce mol ratios of 2.1 to 2.8 and 0.10 to 0.38, respectively, per mol of phenol, for a period of at least two minutes at reflux to produce a liquid phenol-formaldehyde thermosetting resin. The setting time can be decreased, if desired, by using two portions of syrup, reacting one portion for a greater time-temperature period than the other and combining the two portions.

Abstract: Dispersions containing (a) a pigment, (b) an oxalkylated novolak, (c) urea and/or a compound containing at least 2 long-chain aliphatic groups and which are connected via a bridge member containing ester and/or amide groups, and (d) water and/or agents retarding drying up, and, optionally, usual adjuvants, are useful for pigmenting natural or synthetic materials, especially aqueous systems containing cellulose ethers.

Abstract: Particulate resoles are produced by mixing phenol, formaldehyde and amine in an aqueous medium containing a protective colloid. The resoles exhibit improved cure rate and sinter resistance when an alkaline compound is added to the reaction mixture after particulate formation.

Abstract: Carboxylate salts, prepared by a Mannich reaction and useful in the preparation of water-borne coatings, have the general formula ##STR1## where R.sup.1 represents an aliphatic, aromatic, or araliphatic divalent group which may contain a further --COO.sup.- M.sup.+ ; R.sup.2 represents --H, --CH(R.sup.3)N(R.sup.10)R.sup.1 COO.sup.- M.sup.+, or alkyl which may be substituted by --COO.sup.- M.sup.+, --CH(R.sup.3)OH, or --CH(R.sup.3)OR.sup.8, R.sup.1 and R.sup.2 containing together not more than one --COO.sup.- M.sup.+ ; R.sup.3 represents --H or alkyl; each R.sup.4 represents --H, halogen, alkyl, or alkenyl; R.sup.5 represents --H, halogen, alkyl, alkenyl, or a group --CH(R.sup.3)OH, --CH(R.sup.3)OR.sup.8, or --CHR.sup.3 --NR.sup.2 --R.sup.1 --COO.sup.- M.sup.+ ; either R.sup.6 represents --H and R.sup.7 represents the residue of a polyepoxide, preferably of average mol. wt. 1000-5000, or R.sup.6 represents a covalent bond linked to the group R.sup.7, and R.sup.

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.