PROCEDE DE PRODUCTION D'UNE COMPOSITION DE NOYAU DE FONDERIE. (

摘要

1364343 Foundry core composition QUAKER OATS CO 2 Feb 1972 [3 Feb 1971] 4966/72 Heading C1H [Also in Division C3] A foundry core composition is made by forming a monomeric binder mixture of from 2 to 10% by weight urea-formaldehyde mixture, from 97À9875 to 89À5 wt. per cent furfuryl alcohol and from 0À0125 wt. per cent to 0À5 wt. per cent of a silane coupling agent, forming a second mixture of acidic catalyst and sand, and mixing 99À5 to 95 wt. per cent of second mixture with ¢ to 5 wt. per cent of monomeric binder mixture. The urea-formaldehyde mixture contains from 5 to 25 wt. per cent water. The silane coupling agent is of the general formula X-R<1>-Si-(OR<11>)3, where R<1> = alkylene C2H2n, n = 3-6, R<11> = aryl, substituted aryl, alkyl or heteroalkyl radical and X = amino, mercapto, epoxy or glycidoxy. Examples of silane coupling agents are listed. The acidic catalyst, which aids resinification of the furfuryl alcohol (e.g. toluene sulphonic acid, phosphoric acid, ammonium chloride, ammonium trichloroacetate, ammonium phosphate, ammonium sulphate, ammonium nitrate) is present in an amount of from 5% to 50% by weight of the monomeric binder.