Patent GB-838245-A (GB)
Title: Improvements in or relating to photographic reproduction
IPC: C07D233/84
Filed: 1957-11-15
Abstract: A composition for use on a support in electro-photography comprises a natural resin (which may be modified) together with a 4 : 5-diphenyl-imidazolin-2-one or -2-thione, optionally substituted in the 1,3-positions by alkyl or phenyl (and in which any phenyl group can carry alkyl, alkoxy, hydroxy, amino or halogen substituents), with or without a sensitizing dyestuff. Specified resins are Manila copal, colophony esterified or modified with formaldehyde, zinc resinate, and polymerized (e.g. dimerized) or hydrated natural resins.  Suitable imidazolines and sensitizing dyestuffs are listed. Specifications 633,747 and 633,796 are referred to.ALSO:Imidazolines of the formula <FORM:0838245/IV (b)/1> where X and Y are H, alkyl or phenyl, Z is O or S, and any phenyl group may be substituted with alkyl, alkoxy, hydroxy, primary secondary or tertiary amino, or halogen, are prepared by condensing benzoin or a substituted benzoin with urea or thiourea substituted by X and/or Y as appropriate; the reactants are boiled in a lower fatty acid, e.g. acetic or propionic. An example is given of the preparation of 4 : 5-di-(p - chlorophenyl) - imidazolone from 4 : 41-dichlorobenzoin and urea.  Other imidazolones prepared similarly are 4 : 5-diphenyl, 1-methyl-4 : 5 - diphenyl, 1 : 3 : 4 : 5 - tetraphenyl, 4 : 5 - bis - (methylenedioxyphenyl), 4 - phenyl-5 - p - dimethylaminophenyl, 4 : 5 - di - (m-chlorophenyl, 1 : 3 - di - (p - chlorophenyl)-4 : 5 - diphenyl, 1 : 3 - di - (m - bromphenyl)-4 : 5 - diphenyl, 4 : 5 - di - (p - methoxyphenyl), 4 - (m - chlorophenyl) - 5 - (31 : 41 - dimethoxyphenyl), 1 : 3 - diphenyl - 4 : 5 - di - (p - methoxyphenyl), 1 : 3 : 4 : 5 - tetra - (p - methoxyphenyl), 4 : 5 - di - p - tolyl, 1 : 3 - di - p - tolyl - 4 : 5 - diphenyl, 4 - (p - methylaminophenyl) - 5 - phenyl, 4 - (p - diethylaminophenyl) - 5 - phenyl, 4 - (p - dimethylaminophenyl) - 5 - (p - chlorophenyl) and 4 : 5 - di-(p - acetylaminophenyl).  Imidazole - 2 - thiones prepared are: 4 : 5 - diphenyl, 1 : 4 : 5 - triphenyl, 1 : 3 : 4 : 5 - tetraphenyl, 1 : 4 : 5-triphenyl - 3 - chlorophenyl (all isomers), 1 : 4 : 5 - triphenyl - 3 - (p - bromophenyl), 1 : 3 - diphenyl - 4 : 5 - di - (p - methoxyphenyl), 1 : 4 : 5 - triphenyl - 3 - (p - methoxyphenyl), 1 : 3 - di - (p - ethoxyphenyl) - 4 : 5 - diphenyl, 1 - o - tolyl - 3 - (p - methoxyphenyl) - 4 : 5-diphenyl, 1 - (p - hydroxyphenyl) - 3 : 4 : 5-triphenyl, 1 : 3 - di - p - tolyl - 4 : 5 - diphenyl, 1 : 4 : 5 - triphenyl - 3 - o - and p - tolyl, 1 - p-tolyl - 3 - o - tolyl - 4 : 5 - diphenyl, 4 : 5 - di-(methylenedioxyphenyl) and 1 : 3 - di - (p - dimethylaminophenyl)-4 : 5-diphenyl.  4 : 5 - Di - (p - aminophenyl) - imidazolone is made by acid hydrolysis of its N : N1-diacetyl derivative and is isolated via the hydrochloride.  N - (o - tolyl) - N1 - (p - methoxyphenyl) - thiourea is prepared from p-anisidine and o-tolyl mustard oil.  p-Methylamino-benzoin is obtained by heating a mixture of benzaldehyde and p-methylaminobenzaldehyde with potassium cyanide.  1 : 3 - Dimethyl - 4 : 5 - diphenyl - imidazolone is made by methylation of 4 : 5-diphenylimidazolone.  4 : 5 - Di - (p - bromophenyl) - imidazolone is prepared by direct bromination in sulphuric acid.ALSO:A composition for use on a support in electrophotography comprises a synthetic resin together with a 4 : 5-diphenyl-imidazolin-2-one or -2-thione, optionally substituted in the 1 : 3-positions by alkyl or phenyl (and in which any phenyl group can carry alkyl, alkoxy, hydroxy, amino or halogen substituents, with or without a sensitizing dyestuff.  Examples are given of compositions containing the following resins:-resin-modified maleic acid, and ketone.  Other types of resins mentioned are phenolic (especially phenol-formaldehyde, which may be modified with colophony); indene, polyvinyl chloride, acetate, acetals, alcohol and ethers; chlorinated polyvinyl chloride; polyacrylic and methacrylic esters; poly-styrene and isobutylene; phthalates; alkyds; maleic acid resins; colophony esters of mixed higher alcohols; urea-and melamine-formaldehyde, xylene-formaldehyde; polyamides and polyurethanes; aldehyde resins; ketone resins.  Suitable imidazolines and sensitizing dyestuffs are listed.  Specifications 633,747 and 633,796 are referred to.