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
  • G03C1/00—Photosensitive materials
  • G03C1/52—Compositions containing diazo compounds as photosensitive substances
  • G03C1/54—Diazonium salts or diazo anhydrides
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
  • G03B27/00—Photographic printing apparatus
  • G03B27/02—Exposure apparatus for contact printing
  • G03B27/14—Details
  • G03B27/30—Details adapted to be combined with processing apparatus
  • G03B27/303—Gas processing
• • 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
  • G03C1/00—Photosensitive materials
  • G03C1/52—Compositions containing diazo compounds as photosensitive substances

Definitions

• This invention relates to a method of obtainlight according to the invention consists in the ing photographic contrasts by means of diazouse of 'a carrier provided with a diazonium comnium compounds.
• diazo type is I pound (or with a plurality of such diazonium known to be based on the production of azo dyes compounds) which on exposure'in the presence of 5 by the coupling of a diazonium compound with an water forms primarily a phenol so substituted in 5 azo component and in addition to the fact that the benzene nucleus that this phenol can be oxidiazonium compounds are decomposed by exdized by the diazonium compound itself or by a posure and are thus deprived of their property further diazonium compound also'present in the of coupling with azo-components to form azocarrier to form a colored compound, the medium l0 dyes.
• the carrier being such that the speed at which 10 cording to which paper provided with diazonium this oxidation process proceeds is greater than compounds is exposed under a diapositive or a 2 that at which the diazonium compound couples drawing and then treated with a solution of an with the phenol to form an azo-dye but during azo-component.
• the non-exposed parts are thus the exposure is smaller than that at which the coloured so that a positive of a positive is obdiazonium compound is converted by the said ex- 15, tained.
• a further known method involves the posure, and that the phenol is caused to be oxi use of paper containing a diazonium compound dized by the diazonium compound not yet conwhich on exposure is converted into a phenol verted t'o-form a colored oxidization product. which is then used as an azo component.
• the invention includes also almethod of obtaincase the phenols thus obtained may be caused to lug heliographic prints which is characterized 20 couple with some diazonium compound, but it is by the use of a carrier provided with a diazonium also possible to bring about a coupling with the compound which, after the local exposure and diazonium compound from which the said phewithout any other substance being added after n01 is produced. For this latter purpose it is the exposure, is caused to form a dye which is as often necessary to introduce the paper into an n t an azo-dye.
• a sufiicient quantity of diazonium compound has may mention those having in the benzene nur m in .1 is p l to cause e phen l f rm cleus at least one OH-group substituted in ortho to coup e w t the di o p u Still P or para position relativelyto the diazonium 30 eht y introducing h aser a e an alkegroup. In some cases the OH-group, which in line medium.
• the method according to the invention is based para position relatively to the diazonium group, on quite a different principle: it does not utilize may be replaced by a NH: group one of the hyt coupling p p ti f dia onium omp u d drogen atoms of which may be replaced in some 35 u s bas d o t oxidizing P pe s of cases by an alkyl-, aryl-, or similar group. tain diazonium compounds.
• the parts struck by this light first exhibit an intermediate red violet colour which on continued exposure changes to light yellow. It may be observed in this connection that this whitening of the intermediate red violet colour al'so ensues when the exposed paper is kept in daylight or even in the dark. After the said strongly actinic exposure the paper, with the drawing removed, is exposed to daylight. Daylight is much less actinic relative to the diazonium compound mentioned in this example so that there is now a question of a slightly actinic exposure.
• the paper above described contains a diazonium compound which on exposure yields a polyphenol that is not adapted to couple with a diazonium compound to form an azo-dye, since hydroquinone is not possessed of this property.
• the slightly actinic exposure may be obtained by short exposure to light having a high specific actinic effect relatively to the diazonium compound used or to a feeble light source producing such light.
• the action may be influenced by altering the distance of the light source.
• Example 2 Paper is provided with orthohydroxybenzenediazonium chloride; otherwise, the process may be carried out similarly to Example 1.
• the diazonium compound used in this case differs from that mentionedin the first example in that the intermediate colour produced by the strongly actinic exposure is orange red.
• the stability of the paper providedwith a diazonium compound but not yet exposed may be increased by choosing as the acid residue of the diazonium compound a slightly volatile acid, such as sulphuric acid; for this purpose, preferably, a diazonium compound may be: used which contains a sulpho acid group substituted in the nucleus.
• Example 3 Paper is provided with l-hydroxy-2-diazo-4- benzenesulphonic-acid.
• the strongly actinic exposure under a drawing is now efiected by daylight, because daylight is strongly actinic with respect to the said compound; on the contrary for the slight actinic exposure ultraviolet light may be resorted to because ultra-violet light is slightly actinic with respect to the said diazonium compound. Otherwise, the process may be efiected similarly to the above examples so that consequently also a positive of a positive is obtained.
• the coloured oxidation product has an orange red colour whereas the base is light yellow.
• the slightly actinic effect may be obtained by a very short exposure to the light source used for the strongly actinic exposure and then the oxidation of the phenol formed may be brought about by the diazonium compound by subsequent preservation in the dark.
• paper normally contains suflicient water for the conversion of the diazonium compound into the phenol by the ex-' posure.
• the oxidation reaction can be considerably accelerated by a-moderate heating, for instance to 80 C.
• a-moderate heating for instance to 80 C.
• the paper should be kept as cold as possible as otherwise the base is coloured too much.
• the formation of contrasts can be considerably promoted by means of copper salts, such as copper nitrate.
• Example 4 Paper is soaked in a 0.25% alcoholic solution of 1-hydroxy-2-diazo-4-benzenesulphonic acid having added to it 0.55% of copper nitrate. After drying it is exposed under a drawing for 20 seconds to a carbon arc lamp (for'example in a heliographic printing machine), after which the drawing is removed and the paper is heated for some time to 80 0. Thus a positive of a positive in a dark grey tone is obtained.
• a carbon arc lamp for'example in a heliographic printing machine
• the invention is based on the oxidation of the product produced from the diazonium compound by exposure so that for use in' carrying out the invention such diazonium compounds are particularly suitable which yield on exposure readily oxidizable products which are oxidized by the diazonium compound to form a dark-coloured oxidation product.
• the invention presents inter alia the advantage that the particularly suitable diazonium compounds just referred to are simple compounds having their diazonium group in a benzene nucleus. Very good contrasts may be obtained with those diazonium compounds that have an OH-group in the ortho or para position in the benzene nucleus.
• use may be made of a multiple diazotized polyamino compound which on exposure passes into a polyphenol, in which case the compound should be such that two of the diazonium groups are in ortho or para relation to each other.
• the present invention permits of producing so-call'ed integral heliographic prints which obviate the need for some chemical after-treatment.
• a chemical after-treatment is even preferably avoided in some cases,particularly an after-treatment with alkali, such as gaseous aqua-ammonia, since in a medium of aqueous-ammonia an oxidation, by oxygen from the air, of the compounds at the spots copied out by the strongly actinic exposure ensues as well.
• diazonium compounds having at least one NH: group in ortho or para relation to the diazonium group in the benzene nucleus are also suitable for use in carrying out the invention.
• said diazonium compounds pass into an amino phenol which by the diazonium compound from which it is formed can be readily oxidized to-form a coloured oxidation product.
• paper instead of paper other materials, such as glass, film or paper provided with a gelatine layer, may be used as the carrier of the diazonium compounds described.
• Such material permits of obtaining photographic prints by carrying out the invention which will beset out more fully by reference to some examples.
• Example 6 converted. During the said rinsing with water, the polyphenol formed is oxidized by the excess of the diazonium compound present to form a coloured oxidation product and the greater the quantity of light that-has acted the darker are the tones. obtained, as the coloured oxidation product is insoluble. The excess of diazonium compound is washed out.
• the exposure is so effected that even at those spots upon which most of the light has fallen there remains always an excess of diazonium compound.
• an unduly prolonged exposure results in copying out and thus less dye formation or no dye formation at all can be obtained so that in the case of an excessively long exposure even anegative of a negative is obtained.
• Example 8 diazonium compound, or-glass, film or paper or the like provided with a gelatine coating to which the Examples 6, 7 and 8 refer it may be preferable that the oxidation reaction should be accelerated by bathing for a short time in aquaammonia.
• water is used for washing out and the aqua ammonia treatment is only of short duration, neither oxidation of the bottom by oxygen from the air nor coupling practically ensues in this case.
• the carrier may be treated, prior to its being washed out with water, with an ammoniacal copper solutlon'which obviates the need of adding copper salt to the diazonium compound of the carrier.
• the durability of soaked papers is greater than that of soaked gelatine papers and Cellophane.
• the invention may alsobe practised for making direct photographic exposures, in which case generally longer exposure times are used, since usually the quality of actinically active light available is smaller.
• the diazonium compounds adapted for carrying out the invention do not group themselves according to the usual system of organic chemistry.
• the light-sensitive substances used are broadly light-sensitive benzene-diazonium compounds; of these a great number and variety are adapted to carry out the invention.
• a decomposition product phenol
• phenol decomposition product
• the speed of oxidation is less than the speed of decomposition (conversion) of the diazonium compound during the exposure, and provided the speed of oxidation is greater than the speed at which the decomposition product (phenol) produces, with the diazonium compound, an azo-dye.
• This formation of colored matter takes place to a great extent subsequent to-the actual exposure, and as a rule without further exposure or addition of any further substance after the exposure, and thus a self-development of the light-sensitive layer takes place.
• selectively exposing should refer to the exposing of the carrier provided with a light sensitive diazonium compound, both through a suitable negative or positive.
• the process of making light prints comprising the steps, forming a light sensitive layer by applying to a carrier 2.
• light sensitive substance comprising a benzene-diazonium compound, selectively exposing said carrier to actinic light to partially decompose the diazonium compound at selected portions, forming a phenol and oxidizing into colored products the phenol so formed by the undecomposed diazonium compound remaining at these portions, by providing a speed of oxidation which is greater than the speed at which the benzene-diazonium compound would form an azo dye with the phenol, said selected portions forming a colored contrast with the substantially uncolored remainder of the carrier.
• the process of making light prints comprising the steps, forming a light sensitive layer by applying to a carrier a light sensitive substance comprising a benzene-diazonium compound, selectively illuminating said layer with a strongly actinic light to partially decompose on' selected portions said diazonium compound, forming a phenol substituted in the benzene nucleus and oxidizing said phenol by non-decomposed diazonium compound at the weakly-illuminated portions at a rate which is greater than the rate at which the diazonium compound could couple with the phenol to form an azo dye, to thereby form on said weakly-illuminated portions a colored oxidation product, and photochemically decomposing during said illumination the diazonium compound at the strongly-illuminated portions at'a rate which is greater than-is the rate of oxidation of the phenol, to maintain said strongly illuminated portions substantially uncolored.
• Process of making light prints comprising the steps, forming a light sensitive layer by applying to a carrier a light sensitive substance comprising a benzene-diazonium compound, selectively illuminating said layer with weakly actinic light to partially decompose on said selected portions said diazonium compound forming a phenol substituted in the benzene nucleus, and oxidizing said phenol by a non-decomposed diazonium comprising a benzene-diazonium compound, se-
• the method of producing a photographic print comprising the steps of providing one carrier a light sensitive benzene-diazonium compound selected from the group p-hydroxybenzenediazoniumchloride, 1 hydroxy 2'- diazo-4-benzene sulphonic acid, orthohydrobenzenediazoniumchloride, p-phenylaminobenzenediazoniuinchloride, orthophenoldiazoniumsulphate, selectively exposing said carrier to actinic light to partially decompose the diazonium compound at selected portions, forming a phenol and oxidizing into colored products'the phenol so formed by the undecomposed diazonium compound remaining at these portions, by providing a speed of oxidation which is greater than the speed at which the benzene-diazonium compound would form an azo dye with the phenol, said selected portions forming a colored contrast with the substantially uncolored remainder of the carrier.
• a light sensitive benzene-diazonium compound selected from the group p-hydroxybenz

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
• Heat Sensitive Colour Forming Recording (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=19785803

Family Applications (1)

Country Status (5)

Cited By (8)

• 0
  • BE BE388671D patent/BE388671A/xx unknown
• 1931
  • 1931-05-22 NL NL56995A patent/NL38020C/xx active
• 1932
  • 1932-04-22 GB GB11645/32A patent/GB391970A/en not_active Expired
  • 1932-05-19 US US612364A patent/US2034508A/en not_active Expired - Lifetime
  • 1932-05-20 FR FR737377D patent/FR737377A/fr not_active Expired
  • 1932-07-18 FR FR42120D patent/FR42120E/fr not_active Expired

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