US2514234A - Process for the manufacture of color photographic images - Google Patents
Process for the manufacture of color photographic images Download PDFInfo
- Publication number
- US2514234A US2514234A US779839A US77983947A US2514234A US 2514234 A US2514234 A US 2514234A US 779839 A US779839 A US 779839A US 77983947 A US77983947 A US 77983947A US 2514234 A US2514234 A US 2514234A
- Authority
- US
- United States
- Prior art keywords
- layer
- dye
- image
- compound
- solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000000034 method Methods 0.000 title claims description 14
- 238000004519 manufacturing process Methods 0.000 title description 6
- 239000000975 dye Substances 0.000 claims description 30
- 230000008878 coupling Effects 0.000 claims description 18
- 238000010168 coupling process Methods 0.000 claims description 18
- 238000005859 coupling reaction Methods 0.000 claims description 18
- 150000001875 compounds Chemical class 0.000 claims description 17
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 16
- 229910052709 silver Inorganic materials 0.000 claims description 16
- 239000004332 silver Substances 0.000 claims description 16
- 239000000126 substance Substances 0.000 claims description 10
- -1 AMINO COMPOUND Chemical class 0.000 claims description 6
- 239000003638 chemical reducing agent Substances 0.000 claims description 5
- 239000000243 solution Substances 0.000 description 25
- 150000008049 diazo compounds Chemical class 0.000 description 12
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 6
- 230000006378 damage Effects 0.000 description 5
- LPXPTNMVRIOKMN-UHFFFAOYSA-M sodium nitrite Substances [Na+].[O-]N=O LPXPTNMVRIOKMN-UHFFFAOYSA-M 0.000 description 5
- BMYNFMYTOJXKLE-UHFFFAOYSA-N 3-azaniumyl-2-hydroxypropanoate Chemical compound NCC(O)C(O)=O BMYNFMYTOJXKLE-UHFFFAOYSA-N 0.000 description 2
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 239000000987 azo dye Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000001066 destructive effect Effects 0.000 description 2
- 238000006193 diazotization reaction Methods 0.000 description 2
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 2
- 235000010288 sodium nitrite Nutrition 0.000 description 2
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 description 2
- KJCVRFUGPWSIIH-UHFFFAOYSA-N 1-naphthol Chemical compound C1=CC=C2C(O)=CC=CC2=C1 KJCVRFUGPWSIIH-UHFFFAOYSA-N 0.000 description 1
- 229940126062 Compound A Drugs 0.000 description 1
- NLDMNSXOCDLTTB-UHFFFAOYSA-N Heterophylliin A Natural products O1C2COC(=O)C3=CC(O)=C(O)C(O)=C3C3=C(O)C(O)=C(O)C=C3C(=O)OC2C(OC(=O)C=2C=C(O)C(O)=C(O)C=2)C(O)C1OC(=O)C1=CC(O)=C(O)C(O)=C1 NLDMNSXOCDLTTB-UHFFFAOYSA-N 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 150000001989 diazonium salts Chemical class 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000004043 dyeing Methods 0.000 description 1
- 239000000839 emulsion Substances 0.000 description 1
- 210000004907 gland Anatomy 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000012266 salt solution Substances 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 239000001117 sulphuric acid Substances 0.000 description 1
- 235000011149 sulphuric acid Nutrition 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
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
- G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
- G03C7/28—Silver dye bleach processes; Materials therefor; Preparing or processing such materials
Definitions
- the production of the dye image can be performed either by coupling with a diazo compound or coupling with an azo coupler, respectively, and the destruction atthe image or non-image parts of the dye thereby obtained.
- the process includes the step of diazotization, in addition to coupling and destruction at the image or non image parts of either the diazo compound or the dye.
- the present invention relates to the treatment of photographic layers that either comprise both a diazotizable amino compound and a compound A i .1 i'f i i that iscapable of coupling with diazo compounds or that comprise a compound'which is "both diazotizable and'then capable of coupling with itself.
- the operations'of diazotization, coupling and destruction at the image parts are not carried out in three separate treating steps butwith only two baths or even' with one single bath.
- This simplification of the process is rendered possible by the present invention whiichconsists in imparting a triple function to the-treating solution or a dual function to one oftwo. treating solutions so that the same treating solution is 'soin' which is distributed diffusely throughout the layer is treated for about 5 minutes with a solution of 250 ccs. of a 0.25-normal sulphuric acid and 1 cc. of a 0.1 normal-sodium nitrite'solution.
- the image is washed and immersed for about 5 minutes into a 2.5% thiocarbamide solution 7 containing 2% acetic acid which causes coupling occur within the same solution. Aiter ab'out 10 to 20 minutes the silver is removed from the 3 dye image.
- the dye image can be improved by treating the layer prior to the removal of the silver with a dye destroying solution, such as a 5% hydrobromic acid solution.
- Example: 3;f- A silver images-as used in Example 1 is treated with a'solution of cos. /z-n'ormal acetic acid containing 5% sodium chloride and 0.1 cc. of a (Ll-normal sodium nitrite solution. After 20 minutes the silver image isremoved by a cupric salt solution and fixinglifa 'dyeimage is obtained.
- Example 4 A silver image as used in Example 1 is treated with cos.- "of a'solution of 0.25- normal hydrobromic acid to which 0.1 cc. of a 0.1-normal sodium nitrite: solutionv have been.
- diazonium compound at tl'i'e'points'of'thewsilver image.
- the layer is after-treatedwith a' illz5- normal sodium carbonate to cause'ithe dia'zotized T T.
- the silver is removed, and
- the process of the present invention for the production of color photographic images is espe- "ceially useful for the manufacture of multi-color images in a plurality of layers.
- a process gimp-producing a reversed photo- -'-graphic'dyestuff image in a; layer comprising a silver image and adiazotizablefamino compound distributed diffusely throughout said layer, which 1 comprises treating said layerswith a. solution which causes said compound to be .diazotized and '1 then treating said layer 1 with; a single solution to -:.-"pro,duce a reversed dyestufiiimagewhich solution causes 'coupling-of the diazotiaed compound to -"form- 'a dye in the presence of.
- a reversed photographic dyestuff image in a layer comprisin a enter-"image and an amino compound distributed diiiusely throughout said layer which is both dialzbtizable and then capable of coupling WithTitSBif to form a dye
- which comprises treating said layer with a solution which causes said emeteries e siized.end henir a ng s 25 ;layer;with ,a single solution'to produce a reversed dyestufieimagelwhich solution causes the id i'aiotized,,compound to couplewit'hit'self'to form a dye invthe presenceof a substance which is nondestructive, withgre'spec't tcsaid dye but reacts with said 'ilyer image to gxidiz'e' it' and substan- - g a h edyestuff.i 35.
- Witliffesp'ect tgj said dyeig'ut'reactswith said 'silver image to. oxidize it ,andjsubs'tantially simultane- ..oiisly to io mareducing substance.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
Description
Patented July 4, 1950 2,514,234 raocsss FOR THE MANUFACTURE or COLOR PHOTOGRAPHIC IMAGES Bla Gaspar, Beverly Hills, Calif., assignor to Chromogen, Incorporated, a corporation of Nevada No Drawing. Continuation 'of applicationSerial No. 541,282, June 20, 1944, which is adivision of application Serial No. 518,256, January 14, 1944, which in turn is a division of application Serial No. 351,907, August 8, 1940. This application October 14, 1947, Serial No..779,839. In Great Britain August 9, 1939 6 Claims.
The present application is a continuation of my application Serial No. 541,282, filed June 20, 1944, now abandoned. Application Serial No. 541,282 is a division of ,my application SerialNo. 518,256, filed January 14, 1944, which inturn is a division of my Patent 2,361,541 which relates to the production of dye images, from photo-'-' graphic silver images by a process which comprises the synthesis of an azo dye in the exposed photographic emulsion layer.
In my prior United States Letters Patent No. 2,071,688, dated February 23, 1937, I have described and claimed a method of producing color photographic images in which the photographic layer is subject to twotreatments, the first .treatment consisting inthe conversion of a dye-forming substance into a dye and the second treatment consisting in the local dye destruction at the required points in accordance withv my Patent 2,020,775. Thus, for example, a diazo compound is transformed into an azo dye by coupling with a phenol; or a phenol or other azo coupler is transformed into an azo. dye by treating with a diazo-compound, the azo .dyes thus formed then being destroyed locally.
In my prior British Patent Specification No. 416,660, as well as in Patent 2,071,688 just mentioned, I have also described and. claimed an alternativeprocess in which the first treatment consists in the local destruction of the dye-forming substance, the :second treatment then consisting in the conversion of the remaining dyeforming substance into the dye.v
If, for carryingout the processes referred to above, a layer is used which contains either an azo coupler or a diazo compound but not both, the production of the dye image can be performed either by coupling with a diazo compound or coupling with an azo coupler, respectively, and the destruction atthe image or non-image parts of the dye thereby obtained. v
If, however, the layer contains a diazotizable amino compound and an azo coupler, the process includes the step of diazotization, in addition to coupling and destruction at the image or non image parts of either the diazo compound or the dye.
The present invention relates to the treatment of photographic layers that either comprise both a diazotizable amino compound and a compound A i .1 i'f i i that iscapable of coupling with diazo compounds or that comprise a compound'which is "both diazotizable and'then capable of coupling with itself. The operations'of diazotization, coupling and destruction at the image parts are not carried out in three separate treating steps butwith only two baths or even' with one single bath.
This simplification of the process is rendered possible by the present invention whiichconsists in imparting a triple function to the-treating solution or a dual function to one oftwo. treating solutions so that the same treating solution is 'soin' which is distributed diffusely throughout the layer is treated for about 5 minutes with a solution of 250 ccs. of a 0.25-normal sulphuric acid and 1 cc. of a 0.1 normal-sodium nitrite'solution.
The image is washed and immersed for about 5 minutes into a 2.5% thiocarbamide solution 7 containing 2% acetic acid which causes coupling occur within the same solution. Aiter ab'out 10 to 20 minutes the silver is removed from the 3 dye image. The dye image can be improved by treating the layer prior to the removal of the silver with a dye destroying solution, such as a 5% hydrobromic acid solution.
Example: 3;f- A silver images-as used in Example 1 is treated with a'solution of cos. /z-n'ormal acetic acid containing 5% sodium chloride and 0.1 cc. of a (Ll-normal sodium nitrite solution. After 20 minutes the silver image isremoved by a cupric salt solution and fixinglifa 'dyeimage is obtained.
Example 4.A silver image as used in Example 1 is treated with cos.- "of a'solution of 0.25- normal hydrobromic acid to which 0.1 cc. of a 0.1-normal sodium nitrite: solutionv have been.
diazonium compound at tl'i'e'points'of'thewsilver image. The layer is after-treatedwith a' illz5- normal sodium carbonate to cause'ithe dia'zotized T T.
The silver is removed, and
compound to couple. a reversed dye image obtained.
From the foregoing examples it will be seencarbonyl :fbi's' E8 (4s4eaminmbenzamino),
mind) naphthol -fl) disulphonic acid-;(3 fi)1 Beilste'ins Handbuclr: der' Organischen: Chemi, th (26.2, 1933, Su'ppllNol; XIV, page '759;=F.formula may be used which" are distributed difi'usely throughout a layer.
The process of the present invention for the production of color photographic images is espe- "ceially useful for the manufacture of multi-color images in a plurality of layers. In the multiflayer-material used-for thi process some -or all "fof. thelayers-may contain a dyeiorm-ingi subfistance'capable of coupling withsitsel-i: or, some or fiiallbf the layers may contain'a diazotizable amino ompound-anda= compound that is capable of oupling Fwith diazo-compounds,.- a a claim? 91; A process gimp-producing :a reversed photo- -'-graphic'dyestuff image in a; layer comprising a silver image and adiazotizablefamino compound distributed diffusely throughout said layer, which 1 comprises treating said layerswith a. solution which causes said compound to be .diazotized and '1 then treating said layer 1 with; a single solution to -:.-"pro,duce a reversed dyestufiiimagewhich solution causes 'coupling-of the diazotiaed compound to -"form- 'a dye in the presence of. a' substance which e "isnon-destruetivewith respect .to...sa id .dye' but --reacts with saidsilver image-.to oxidize it and esubstantially simultaneously t0 f0,rrn a reducing substance.
2. A process for producing a reversed photoa compoiinw which fastl.Y; idyes a; silveri halide graphic dyestuff image in a layer comprising a silver image together with a diazotizable amino compound and a compound capable of coupling with diazo compounds, said compounds being uniformly distributed throughout said layer,
which comprises treating said layer with a solution which causes said diazotizable amino compound to be diazotized and then treating said layer-with a single solution to produce a reversed dyestuff image which solution causes coupling of the diazo compound with the compound capable of coupling thereto, to form a dye in the presence of a substance which is non-destructive with respect to said dye but reacts with said silver image to oxidize it and substantially simultaneously to form a reducing substance. '3. A process. for producing a reversed photographic dyestuff image in a layer comprisin a enter-"image and an amino compound distributed diiiusely throughout said layer which is both dialzbtizable and then capable of coupling WithTitSBif to form a dye, which comprises treating said layer with a solution which causes said emeteries e siized.end henir a ng s 25 ;layer;with ,a single solution'to produce a reversed dyestufieimagelwhich solution causes the id i'aiotized,,compound to couplewit'hit'self'to form a dye invthe presenceof a substance which is nondestructive, withgre'spec't tcsaid dye but reacts with said 'ilyer image to gxidiz'e' it' and substan- -=g a h edyestuff.i 35. prising a silver in; c mpe e Re ets? spect totheemuls on w 4 7 throughout said layergwhich"comprises l-trating i l r wi h a sq ij ien w ich. ause Said 40 pound to iiedia zotiz gland then tr'eatiii'gfs .idlay- .er with a single 'splutionfto produce a reversed dyestufiimage, which solutionicau'ses'coupling of the diazotized compound" to form a dye in the presenceof asubstance whichis non-destructive f. Witliffesp'ect tgj said dyeig'ut'reactswith said 'silver image to. oxidize it ,andjsubs'tantially simultane- ..oiisly to io mareducing substance.
5. A process for-produc ng a reversed'photosg ereiasre m .imaee i a: x s pr'isingfa'siiver, image tggether with a dia'z otizable amino compour d pos'ses'sing' dyeing propei ties tl 1;.,r spect to the em ilsion 1ayer and a compound"ca'fgable er coupling with uiaze'ecmpcu'rrss, said compounds ,being un'iiormly distributed throughout jsaid layen' which comprises treating said'layer with a solutiqn'fwhich au'ses said'dia zotizablaamino compound to be diazotized and I ,then. treating said;- layer with a single solution to .produce a reversedjdyestufflimage, which solution 0 causes coupling'of the diazo compound with the compound capable of coupling? thereto tciorm a dye in the presence of a substance which is nondestructiyejwith respect to 'sa.id jdye but reacts with said silver image to oxidize it and'substantially simultaneously to" form a reducing substance. V I
6..A process for producing'a' reversed photo- I graphic dyestufi image in a layer comprising a silverirnage anda diazo compound distributed diffusely throughout said layer, which comprises treating said layerwith a single solution to'prcduce. a reversed dyestufi image which solution causescouplmg of the diazo compound to form a dye in the presence of'a substance whichis' nondestructive with respect to said dye but reacts 8 with said silver image to oxidize it and substantially simultaneously to form a reducing substance.
BELA GASPAR.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date Lierg May 13, 1930 Number Number 10 298,979 416,566
Great Britain Sept. 10, 1934
Claims (1)
1. A PROCESS FOR PRODUCING A REVERSED PHOTOGRAPHIC DYESTUFF IMAGE IN A LAYER COMPRISING A SILVER IMAGE AND A DIAZOTIZABLE AMINO COMPOUND DISTRIBUTED DIFFUSELY THROUGHOUT SAID LAYER, WHICH COMPRISES TREATING SAID LAYER WITH A SOLUTION WHICH CAUSES SAID COMPOUND TO BE DIAZOTIZED AND THEN TREATING SAID LAYER WITH A SINGLE SOLUTION TO PRODUCE A REVERSED DYESTUFF IMAGE WHICH SOLUTION CAUSES COUPLING OF THE DIAZOTIZED COMPOUND TO FORM A DYE IN THE PRESENCE OF A SUBSTANCE WHICH IS NON-DESTRUCTIVE WITH RESPECT TO SAID DYE BUT REACTS WITH SAID SILVER IMAGE TO OXIDIZE IT AND SUBSTANTIALLY SIMULTANEOUSLY TO FORM A REDUCING SUBSTANCE.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB2514234X | 1939-08-09 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2514234A true US2514234A (en) | 1950-07-04 |
Family
ID=10908852
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US779839A Expired - Lifetime US2514234A (en) | 1939-08-09 | 1947-10-14 | Process for the manufacture of color photographic images |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2514234A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1051635B (en) * | 1957-05-09 | 1959-02-26 | Geigy Ag J R | Process for the production of a yellow dye image with the aid of azo dyes by the silver dye bleaching process in a photographic layer, in particular for color photographic purposes |
| US3002964A (en) * | 1957-04-29 | 1961-10-03 | Ilford Ltd | Colour photography |
| US3130049A (en) * | 1959-04-16 | 1964-04-21 | Azoplate Corp | Process for preparing printing plates comprising naphthoquinone diazides reproduction coatings |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB298979A (en) * | 1927-10-18 | 1930-02-20 | Friedrich Lierg | Process of producing pictures consisting of dyes in photographic manner |
| GB416566A (en) * | 1931-12-09 | 1934-09-10 | Bela Gaspar | A method of producing coloured photographic images |
| US2020775A (en) * | 1930-11-07 | 1935-11-12 | Bela Gaspar | Method of producing photographic pictures in colors |
| US2333126A (en) * | 1938-12-19 | 1943-11-02 | Chromogen Inc | Process for producing photographic dye images |
| US2361541A (en) * | 1939-08-09 | 1944-10-31 | Chromogen Inc | Process for the manufacture of color photographic images |
| US2376822A (en) * | 1940-10-22 | 1945-05-22 | Schneider Wilhelm | Production of color photographic images |
-
1947
- 1947-10-14 US US779839A patent/US2514234A/en not_active Expired - Lifetime
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB298979A (en) * | 1927-10-18 | 1930-02-20 | Friedrich Lierg | Process of producing pictures consisting of dyes in photographic manner |
| US1758572A (en) * | 1927-10-18 | 1930-05-13 | Lierg Friedrich | Process of producing pictures consisting of dyes in photographic manner |
| US2020775A (en) * | 1930-11-07 | 1935-11-12 | Bela Gaspar | Method of producing photographic pictures in colors |
| GB416566A (en) * | 1931-12-09 | 1934-09-10 | Bela Gaspar | A method of producing coloured photographic images |
| US2071688A (en) * | 1931-12-09 | 1937-02-23 | Gaspar Bela | Method of producing photographic dyestuff images |
| US2333126A (en) * | 1938-12-19 | 1943-11-02 | Chromogen Inc | Process for producing photographic dye images |
| US2361541A (en) * | 1939-08-09 | 1944-10-31 | Chromogen Inc | Process for the manufacture of color photographic images |
| US2376822A (en) * | 1940-10-22 | 1945-05-22 | Schneider Wilhelm | Production of color photographic images |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3002964A (en) * | 1957-04-29 | 1961-10-03 | Ilford Ltd | Colour photography |
| DE1051635B (en) * | 1957-05-09 | 1959-02-26 | Geigy Ag J R | Process for the production of a yellow dye image with the aid of azo dyes by the silver dye bleaching process in a photographic layer, in particular for color photographic purposes |
| US3130049A (en) * | 1959-04-16 | 1964-04-21 | Azoplate Corp | Process for preparing printing plates comprising naphthoquinone diazides reproduction coatings |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3353984A (en) | Method for the preparation of lightsensitive diazotype materials and improved materials prepared by such method | |
| US2363764A (en) | Color photography | |
| US2514234A (en) | Process for the manufacture of color photographic images | |
| US2020775A (en) | Method of producing photographic pictures in colors | |
| US1821281A (en) | Manufacture of diazo-types | |
| US2361541A (en) | Process for the manufacture of color photographic images | |
| US3445231A (en) | Anti-halation layer for silver halide light-sensitive materials | |
| US2498418A (en) | Production of azo dyestuff images from n-acyl-n-aryl hydrazine developers | |
| US2100594A (en) | Color photography | |
| US2333126A (en) | Process for producing photographic dye images | |
| US2376822A (en) | Production of color photographic images | |
| US2271176A (en) | Process for the manufacture of color photographic images | |
| US2278984A (en) | Method of treating color photographic materials | |
| US2514233A (en) | Process for the manufacture of golor photographic images | |
| GB503873A (en) | A process for producing photographic dyestuff images | |
| US2348894A (en) | Process and treating bath for the production of colored photographic pictures | |
| US2375344A (en) | Color couplers for color development | |
| US2653874A (en) | Process for the production of color photographic images | |
| US3099559A (en) | Silver-free color reproduction process and composition therefor | |
| US2333359A (en) | Color photography | |
| US1594470A (en) | Photographic layer and method of making same | |
| US2616806A (en) | Process for the manufacture of colored photographic images | |
| US2376297A (en) | Process of color photography | |
| US2688542A (en) | Material and process for the production of color photographic images | |
| US2041827A (en) | Colored light-sensitive material and process of producing color pictures therewith |