Patent GB-1018796-A (GB)
Title: Chromogenous tetrakis (aminophenyl) derivatives of benzodifuran and marking method using same
IPC: C09B11/24
Filed: 1962-08-22
Abstract: The invention comprises (A) compounds based on the formula:-<FORM:1018796/C4-C5/1> in which in each heterocyclic ring the two hydrogen atoms attached to one of the carbon atoms are replaced by a pair of p-aminophenyl radicals, (B) compounds having the structure of compounds A but in which the two p-aminophenyl radicals in each pair are joined in ortho positions by an epoxy bridge, (c) compounds having the structure of compounds B but in which the remaining -CH2- group in each heterocyclic ring is replaced by a keto group, (D) N-substituted derivatives of compounds A, B and C in which each N-substituent is alkyl of up to 5 carbon atoms, n-hexyl, cycloalkyl, sulphophenyl, tolyl, methylbenzyl, naphthyl, benzyl, phenyl, chlormethyl or hydroxyalkyl of up to 4 carbon atoms, (E) N-substituted derivatives of compounds A, B and C in which the amino group of the p-aminophenyl group is replaced by a piperidino group, or the entire p-aminophenyl group is replaced by a 9-julolidyl group, and (F) compounds having the structure of compounds A, B, C and D in which the p-aminophenyl group is replaced by a 4-aminonaphthyl group, with the proviso that one or more of the hydrogen atoms on the phenyl rings of the p-aminophenyl groups and on the substituted benzene ring of the formula above may be replaced by methyl, halo or nitro.  The invention further comprises the dark-coloured substances obtained by contacting the compounds above with colour-activating substances which are electrophilic thereto, including attapulgite clay, argosite clay, pyrophyllite, bentonite, halloysite, magnesium montmorillonite, magnesium trisilicate, calcined diatomaceous silica, activated silica, sodium aluminium zeolite, the sulphates of calcium, zinc and barium, basic aluminium sulphate, calcium fluoride, acetic acid, tartaric acid and citric acid.ALSO:A manifolded set, which may be of paper sheets, comprises a first web 11 having on one side a transfer coating 12 containing a colourless or lightly-coloured substance (A), (B), (C), (D), (E) or (F) described below, and a second web 13 carrying on one side an adherent coating 14 containing a colour-activating substance which is electrophilic relative to substance (A), (B), (C), (D), p  (E) or (F), coatings 12 and 14 being in face-to-face relationship so that on impact the substances are brought into contact with each other and a dark-coloured mark is formed.  The substances are (A) compounds based on the formula:- <FORM:1018796/D1-D2/1> in which in each heterocyclic ring the two hydrogen atoms attached to one of the carbon atoms are replaced by a pair of p-aminophenyl radicals, (B) compounds having the structure of compounds A but in which the two p-aminophenyl radicals in each pair are joined in ortho positions by an epoxy bridge, (C) compounds having the structure of compounds B but in which the remaining -CH2-group in each heterocyclic ring is replaced by a keto group, (D) N-substituted derivatives of compounds A, B and C in which each N-substituent is alkyl of up to 5 carbon atoms, n-hexyl, cycloalkyl, sulphophenyl, tolyl, methylbenzyl, naphthyl, benzyl, phenyl, chlormethyl or hydroxyalkyl of up to 4 carbon atoms, (E) N-substituted derivatives of compounds A, B and C in which the amino group of the p-aminophenyl group is replaced by a piperidino group, or the entire p-aminophenyl group is replaced by a 9-julolidyl group, and (F) compounds having the structure of compounds A, B, C and D in which the p-aminophenyl group is replaced by a 4-aminonaphthyl group, with the proviso that one or more of the hydrogen atoms on the phenyl rings of the p-aminophenyl groups and on the substituted benzene ring of the formula above may be replaced by methyl, halo or nitro. Electrophilic colour-activating substances are attapulgite clay, argosite clay, magnesium trisilicate, calcined diatomaceous silica, activated silica, sodium aluminium zeolite, pyrophyllite, bentonite, halloysite, magnesium montmorillonite, the sulphates of calcium, zinc and barium, basic aluminium sulphate, calcium fluoride, acetic acid, citric acid and tartaric acid.  The second web 13 may be modified by the addition of an optional transfer coating 15 similar to coating 12 and one or more additional webs identical with web 13 carrying the coating 15 may be manifolded beneath the modified web 13.  A modified web 13 may also form the top sheet of a manifolded set.  The units of the manifolded set may be fastened together in a pad.  The transfer coating may comprise solid (A), (B), (C), (D), (E), or (F) bonded to the web by a solid adhesive or binder, e.g. a waxy or plastic material, or the coating may be a film-forming material rupturable on impact and containing as a finely dispersed phase numerous cells of a liquid vehicle in which is dissolved the substance (A), (B), (C), (D), (E) or (F).  The film-forming material may be casein, gelatin or polyvinyl alcohol applied as a hydrophilic aqueous composition containing the liquid vehicles emulsified therein.  Vehicles specified are chlorinated biphenyl, benzyl butyl phthalate, benzyl salicylate, phenyl ether or halogenated phenyl ethers and mixtures thereof.  The adherent coating 14 contains the colour-activating substance bonded by a starch or polybutadiene-styrene binder.