Classifications

• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
  • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
  • G03C5/26—Processes using silver-salt-containing photosensitive materials or agents therefor
  • G03C5/29—Development processes or agents therefor
  • G03C5/305—Additives other than developers
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
  • Y10S430/134—Brightener containing

Definitions

• the invention relates to a developer for diazotype printing materials referred to hereinafter as a "diazotype developer.
• a diazotype developer a mixture (either a dry mixture to be dissolved, or a solution) containing as essential constituents one or more azo dyestuff coupling components and one or more potassium and/ or sodium salts of weak acids, such as carbonic acid, boric acid, formic acid, acetic acid, benzoic acid, tartaric acid and citric acid.
• Azo dyestuii components of good coupling activity are used and the alkali salts are so chosen that, in the slight excess used, they ensure sufficient azo dyestuff coupling between the azo dyestufi coupling components and the diazo compound used in the diazotype image the unexposed areas of which containa para-amino-diazo-benzene compound, with the usual quantities of acid con stituents.
• Azo dyestuff components of good coupling activity are, for example S-naphthol, the [i hydroxy-ethyl amide of Z-hydroxy-B-naphthoic acid, phloroglucinol, and resorcinol; an azo dyestuff component of insufficient coupling activity In the Netherlands June 16,
• Diazotype developers are applied practically exclusively in such a manner that their aqueous solution is applied on the diazotype copy in-a layer of, for example, 8 to 12 g./so metre.
• diaaotype develop ers generally also contain substances such as thiourea, alkali thiosulphate, wetting agents, aliphatic polyhydroxy compounds and the like.
• Diazotype developers with borates are to be preferred to those withcarbonates.
• Diazotype developers that have to serve for the development of diazotype copies in which the diazo compound is a para-alkylamino-diazobenzene usually have a pH above .7; those used for diazotype copies containing para-acylamino-diazo-benzene compounds may have a pH alittle below 7,.while their concentration of buffer salts, such as formates, benzoates, and the'like is generally higher.
• diazotype' developers contain optical bleaching agents known per se (of. for example Netherlandspatent specification No. 55,370).
• the diazotype developers according to the in vention contain as optical bleaching agent a blue-fluorescent salt of a p.p-diaminostilbeneo.o-disulphonic acid with one or more 1.3.5- triazine rings attached to the amino groups.
• This type of optical bleaching agent'with at least one triazine ring was found to be more suitable for the above-mentioned application in diazotype developers and to have a greater or more lasting effect than optical bleaching agents without a triazine ring derived from p.p-diaminostilbene-o.o'-disulphonic acid (of. for example French patent specification No. 878,155).
• optical bleaching agents used according to the invention are:
• R1, R2, R3 and R4 stand for amino or aliphatically or aromatically substituted amino groups. Particularly good results are obtained with compounds in which the substituents R1, R2, R3 and R4 are amino groups at least one of which is aromatically substituted, and even better results when one or more of these aromatical ly substituted amino groups have a sulphonic acid or a carboxyl group attached to the arc matic radicle. Many of these can be dissolved in aqueous diazotype developers without any previous treatment. Less soluble optical bleaching agents of the type preferred for the invention may be finely distributed or emulsified in the aqueous developer.
• diazotype copies such as the azo. component B-hydroxy-ethyl amide of 2-hydroxy-naphthalene3-carboxylic acid, the photochemical decomposition product of a diam-compound, a stabiliser such as, for example, naphthalene-1.3.6-trisulphonic acid, and also when the diazotype copies begin to show the familiar discolouration uponageingi It has .3 also bee'n'found thattheeopticalbleaching agents, appliedto the diazotype copy via the diazotype developer, reduce the discolouration of the copy in daylight, a result which is particularly valu+ able when the diazotype copy-ie-ex-posedto light that is relatively rich in rays of short" wave lengths.
• a developer suitable for the development of diazotype paper B is composed as follows:
• Diazotypei paper 8 Base papie'r of"80 gi/s'q metre-' is coated with about 12 g./sq. metre of the following solution Acopy on the diazotype materiaLBisdeveloped by the applicationof. aboutlOg/sq. metre. of the above developer. Adark brownicopy-is'obta-ined in which. the darlebrown-z dyestuff. is in J high con! trastwith the. clear white. ground. If the optical bleaching agent had been omitted iromlthe: composition of the developer, a copy would haveibeen obtained with: a somewhat dingy: background, with whichthe imageiwould contrast considerably 7 less.
• A- copy on diazoty-pe material A. is developed by the application of. about? 1-01" g./'sq. metre of the above developer.
• a developer suitable for the development of diazotype paper A is composed as follows:
• a developer suitable for the development 01 diazotype paper C is composed as follows:
• a brownish-black copy is oh- I l 5o tained in which the brownish-black dyestufi is in g of lsopropyl naphthalene Sm 3 strong contrast with the clearwhite ground. If 2 ac "i "f" the optical bleaching agent had been omitted Tr mm D 05p a e from the composition of the developer copy sodaFsh anhydrous 20 would have been obtained with a somewhat dingy Caffeme 5; ground, with which the image would contr considerably less.
• H0 C H4NH-G I N ⁇ O/ OgNa dome NH NH SOIH 0311 Water g- 1000' What I claim is:
• a copy on diazotype material A is developed by the application of about 10 g./sq. metre of the above developer. A brown copy is obtained, in
• a developer for diazotype printing materials comprising at least one azo dyestuffco'upling component, at least one alkaline metal salt 'of a weak acid and a small amount of a salt of a blueenemas) :sulphonic acid compound containing one 1:315- triazine ring attached to each amino group and having the formula l N.
• R1, R2, R3 and R4 is an aromatically substituted amino group, at least one member of R1, R2 R3 and is analiphat;
• V oaNa AOiNa fin which R1, R2, R3 and R4 are amino groups 3.
• a developer for diazotype printingmaterials ⁇ comprising at least one azo dyestufii coupling cpmponent, at least one alkaline metal salt or" a weak acid and a pp-diaminostilbene-o.o'-disulphonic. acid compound containing one 1 :3 5- t'riazine ring attached to each amino group and having the formula:
• a developer for diazotype printing materials comprising at least one azo dyestufi coupling 30 component, at least one alkaline metal salt of a weak acidand a p.pediaminostilbene-omedisulphonic acid compoundcontaining one 1:-3:5'-tri- C l R:
• v 4 a 4..- A developer f or diazot-ype printing materials comprising at least: one azo dyestu-ff coupling component, at: least one alkalinemetal salt of a weak acid: and a pipadiaminostilbeneaoo ditriazine ring attached to each amino-4 group. and having the formula:
• R1, R2, and R4 is an aromatically substituted amino group and any em inine m m sof R1, Rafts and 34am ,5 Qg oun a A d vel per for diazo ype-pr ingma er al sulphonic acid compound containing one 123:5
• a developer for diazotype printing mate fals comprising at least one azo dyestufi coupling component, at least one alkaline metal salt of a Weak acidand a p;p-diaminostilbene-o.o" cli sulphonic acid compound containing one 123:5-
• R1 and R3 arephenylamino groups and R2 and R4 are phenylamino groups. which are substituted by a sulphoni a d rou icallysulostituted amino group and any remaining 7 in which R1, R2, R3 and R4 are di(hydroxyethyl) amino groups.
• a developer as claimed in claim 4 in which at least one of the aromatic substitutents carries a sulphonic acid group as a substituent.
• a developer as claimed in claim 4 in which at least one of the aromatic substituents carries a oarboxylic acid group as a substituent.
• a process for developing light sensitive sheet material which, at least in the unexposed condition, contains a diazo compound as the light sensitive material comprising applying to the said 110 sheet material a thin film layer of a developer as claimed in claim 1.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
• Luminescent Compositions (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

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Family Applications (1)

Country Status (6)

Cited By (11)

Citations (5)

• 0
  • NL NL7308848.A patent/NL162031B/xx unknown
  • BE BE511670D patent/BE511670A/xx unknown
  • NL NL74109D patent/NL74109C/xx active
• 1952
  • 1952-05-28 US US290563A patent/US2657140A/en not_active Expired - Lifetime
  • 1952-06-13 FR FR1058321D patent/FR1058321A/fr not_active Expired
  • 1952-06-13 CH CH308288D patent/CH308288A/de unknown
  • 1952-06-14 ES ES0204018A patent/ES204018A1/es not_active Expired

Patent Citations (5)

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