Patent GB-344626-A (GB)
Title: Improvements in the manufacture and production of artificial resins and lacquers and artificial masses therefrom
IPC: C08G12/12
Filed: 1930-02-10
Abstract: In the process of the parent Specification, the urea or derivative thereof or the methylolurea or its anhydride is replaced by mixtures of the said urea compounds to give resins when condensed with formaldehyde.  To form lacquers the finely-divided products are dissolved in the solvents used in the first stage of the process, hydroxyl-bearing solvents containing at least four carbon atoms such as aliphatic monohydric alcohols or aliphatic polyhydric alcohols or ethers or esters of the latter which still contain at least one free hydroxyl group or other hydroxyl-bearing compounds such as aliphatic-aromatic alcohols or phenols.  There are also suitable as solvents cyclic ketones such as cyclohexanone, aldehydes such as paraldehyde and furfurol, acetates such as diethyl or dimethylacetal, aliphatic-aromatic ethers such as anisol, cyclic nitrogenous bases such as aniline pyridine or homologues thereof, and difficultly-volatile ethers such as 1-4-dioxane and its homologues. Derivatives of cellulose such as nitro- or acetyl-cellulose or other cellulose carboxylates, or cellulose esters such as benzyl or ethylcellulose, as well as softening agents such as are employed in the lacquer industry may be added.  Such softening agents are, for example, camphor, organic esters of phosphoric acid, ethyl or trichlorethylacetanilide, glycerylmonopropionic or butyric esters or glycerol esters of acetic or benzoic acids or toluene sulphamide or derivatives thereof in which the nitrogen atom is connected with further organic radicles.  Examples are given.ALSO:In the process of the parent Specification, the urea or derivative thereof of the methylolurea or its anhydride is replaced by mixtures of the said urea compounds.  Condensation products of mixtures of the above compounds such as urea and thiourea, urea or thiourea and a methylolurea, or a methylol thiourea, or a methylol urea and a methylol thiourea and formaldehyde are first prepared in organic media consisting of hydroxyl-bearing solvents containing at least four carbon atoms and are then precipitated by the addition of an organic liquid in which the condensation product is insoluble. Suitable solvents are aliphatic monohydric alcohols or aliphatic polyhydric alcohols or ethers or esters of the latter which still contain at least one free hydroxyl group or other hydroxyl-bearing compounds such as aliphatic-aromatic alcohols, e.g. benzyl alcohol, or phenols.  The precipitants are chosen from aliphatic open chain or cyclic hydrocarbons or easily volatile ethers of the aliphatic series which are not acetals, or mixtures of these liquids.  The finely-disintegrated products may be worked up by dissolution into varnishes or they may be pressed and heated to give solid artificial masses.  Suitable solvents are those employed as solvents in the condensation process and cyclic ketones such as cyclohexanone, aldehydes such as paraldehyde or furfurol, acetals such as diethyl or dimethylacetal, aliphatic-aromatic ethers such as anisol, cyclic nitrogenous bases such as aniline, pyridine and their homologues, and difficulty volatile ethers such as 1,4-dioxane and its homologues. In making artificial masses difficulty volatile organic acids such as glycollic, chloracetic, lactic, or salicylic acid may be added to increase the hardness of the final products.  In working up the finely disintegrated products, derivatives of cellulose such as nitro- or acetyl-cellulose or other cellulose carboxylate, or cellulose ethers such as benzyl or ethylcellulose may be added as well as softening agents such as camphor, organic esters of phosphoric acid, ethyl or trichlorethylacetanilides, glycerylmonopropionic or butyric esters, glycerol esters of acetic or benzoic acids, toluene sulphamide or derivatives thereof in which the nitrogen atoms is connected with further organic radicles, or mixtures, of the said agents.  In examples (1) dimethylolurea and dimethylol thiourea are condensed with the aid of oxalic acid in n-butylalcohol and, after neutralization with tertiary sodium phosphate and filtration, precipitated by the addition of ethyl ether; the products can be pressed with or without the addition of glycollic acid or fillers, colouring materials, softeners, resins, derivatives of cellulose or mixtures thereof; lacquers can also be made with the addition of cellulose esters or ethers; (2) trioxymethylene is dissolved in ethylene glycolmonoethylether containing caustic potash, neutralized with sulphuric acid, made acid with hydrochloric, and then gradually incorporated with the anhydride of methylolurea (made by allowing urea and formaldehyde to stand together in the presence of potash) and with a solution of thiourea in ethylene glycolmonomethylether; the whole is neutralized with tertiary sodium phosphate and precipitated with ethyl ether; (3) trioxymethylene is dissolved in isobutyl alcohol made alkaline with caustic potash and the solution is neutralized with sulphuric acid and made acid with hydrochloric acid; dimethylolthiourea and a solution of urea in alcohol is then added and after boiling the solution is neutralized with tertiary sodium phosphate and precipitated with ethyl ether; (4) dimethylolurea and dimethylolthiourea and oxalic acid are dissolved in benzylalcohol and after the heating the solution is neutralized with tertiary sodium phosphate and worked up as in the first example.  The Provisional Specification also describes the use of easily volatile neutral esters and ketones which are free from hydroxyl groups, such as methyl and ethyl acetate, acetone and methylethylketone, as precipitants.ALSO:Containing urea-formaldehyde resins.-In the process of the parent Specification the urea or derivative thereof or the methylolurea or its anhydride is replaced by mixtures of the said urea compounds.  The finely-divided products with or without the addition of difficulty-volatile organic acids such as glycollic, chloracetic, lactic, or salicylic acids to give increased hardness are suitable for moulding.  Fellers, colouring matters, softeners, resins, derivatives of cellulose or mixtures of these substances may be added before pressing the powder.  Suitable cellulose derivatives are nitro-or acetylcellulose or like cellulose carbonylates, or cellulose ethers such as ethyl or benzyl cellulose, and suitable softeners are camphor, organic esters of phosphoric acid, ethyl or trichlorethylacetanilide, glycerol monopropionic or monobutyric esters, glycerol esters of acetic or benzoic acids, or toluene sulphonide and derivatives thereof in which the nitrogen atom is connected with further organic radicles.  Examples are given.