US1374853A - Process of photographic reproduction - Google Patents

Process of photographic reproduction Download PDF

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Publication number
US1374853A
US1374853A US313237A US31323719A US1374853A US 1374853 A US1374853 A US 1374853A US 313237 A US313237 A US 313237A US 31323719 A US31323719 A US 31323719A US 1374853 A US1374853 A US 1374853A
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Prior art keywords
emulsion
photographic
agent
shades
lights
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Expired - Lifetime
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US313237A
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John Robert
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ICONOCHROME Co OF AMERICA
ICONOCHROME Co OF AMERICA Inc
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ICONOCHROME Co OF AMERICA
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Priority to US1417328D priority Critical patent/US1417328A/en
Application filed by ICONOCHROME Co OF AMERICA filed Critical ICONOCHROME Co OF AMERICA
Priority to US313237A priority patent/US1374853A/en
Priority to US313286A priority patent/US1482614A/en
Application granted granted Critical
Publication of US1374853A publication Critical patent/US1374853A/en
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    • 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
    • G03C5/315—Tanning development

Definitions

  • My invention relates to a process of photographic reproduction and has for its object to produce, a printing surface containing a photographic record of lights and dye 01'. ink contact transfer process.
  • An illustrative dye contact transfer process is disclosed in patent to Shepherd and Bartlett, No. 728,310, granted May 19, 1903, for
  • the preferred method is to obtain the photographic record for the printing surface from a completed negative, it may be obtained by direct exposure, as, for example, in a camera, the details'of which method are disclosed in a copending application for Letters Patent Serial No. 327,890, filed October 2, 1919, for process of photo graphic reproduction directly from a negative.
  • the printing surface when treated with dye or ink also may be used in the same manner as a positive, either for directview, or with reflected light, or with trans mitted light as in a projecting machine.
  • he invention isappllcable to monochromatic ol chromatic, or natural color phop t and in 0th in still photograph hotography.
  • - T e term color is inten ed to include fblack, which sometimes technically is designated as an absence of color.
  • a sensit zed emuls1on such as a silver salt emulsion is exposed to the action of light modified by the lights and shades of the completed negative which it is desired to reproduce.
  • the silver salt emulsion may be carried or mounted on any desired support, either opaque, translucent, or transparent, but
  • a transparent carrier such, for example, as glass-tor a cellulose base, in order that the silver salt emulsion may beexposed to the modified light through its transparent carrier.
  • the emulsion then is treated by a developing solution containing a hardening or tanning agent which hardens or renders insoluble or unremovable the emulsion adjacent its light affected, light sensitive content, the effect of which agent is controlled or limited selectively by the resence of varying quantities' of a neutra izing agent, after which the unhardened or soluble or removable portions of emulsion are removed in any desired manner, as, for example, by melting with warm water.
  • a hardening or tanning agent which hardens or renders insoluble or unremovable the emulsion adjacent its light affected, light sensitive content
  • the printing plate or film when treated with coloring matter, may be used as a positive if reproductions are not desired.
  • the hardening or tanning agent is pyrogallic acid
  • the controllin and limiting agent is sodium sulfite which ma be varied in amount selectively within limits to obtain the'desired result.
  • pyrogallic acid also is .a developing agent and that sodium sulfite is a preservative adapted to prevent oxidation of the pyrogallic acid in solution.
  • Other hardening and tanning agentsand other neutralizing agents may be used, the above formula representing one developing solution b which the process may be carried out.
  • otassium bromid for example, also has -a certain controlling and limitin effect.
  • the main difl'erence between t e above sample formula and standard developing formulas is in the amount it is advisable, in order to accelerate the ac- ,7
  • the selectively controlled hardening agent in the developer solution may be used separately if desired, by such modification of the developer solution as will prevent such a hardening of the emulsion as will prevent the selective hardening desired.
  • the hardening or tanning effect of the pyrogallic acid exerts its action first adjacent .the so-called latent image, or in other words, on the portions of emulsion adjacent the partlcles of silver salts affected by the exposure light and con verted bv the developer into metallic silver.
  • the throwing oil of the bromid from a light afiected silver bromid particle in the developing process probably reacts with the pyrogallic acid to harden or tan or render insoluble or unremovable the adjacent emulsion.
  • the reaction products from the chemical efiects of the developer solution are believed to react with the selectively controlled hardening agent.
  • the hardening or tanning effect of the pyro llic acid as above set forth, only the partlc es of emulsion adjacent thesaid light affected particles of silver salts are hardened, the relative proportions -of the hardening agent (whether or not accelerated by an accelerating agent) and-of the neutrallzlng agent being such as to control selectively the eifcctive area of influence of the hardemn a cut.
  • the unhardened portions as state a ve, then may be removed in any desired manner as by placing the emulsion in warm waterv which causes the unhardened or soluble portions to soften and melt away from the hardened or insoluble portions so that the hardened emulsion alone will remain in the form of extremely minute, individual protuberances which are distributed and grouped irregularly so as to represent the photographic lights and shades which it is desired to reproduce. It is preferable that Ill . is more convenient to fix, melt, and bleach,
  • the hardened emulsion may be fixed to remove the silver salts unaffected by light, and bleached to remove the black metallic silver. This may be done in well known-manner, andwhile not necessary, is
  • the order of melting, bleaching, and fixing is not important and may be carried out in any order desired, although it generally in the order named.
  • the printing of positives from the printlng surface may be done by'direct contact.
  • the printing surface is'exposed to the ac-' tion of the desired coloring matter as by placing it in or carrying it through a liq- ,uid color bath.
  • the colored surface then is placed in contact, preferably under some pressure, with the substance on which .the positive is to be made, as by a roller or by a squeegee action.
  • the printing surface prepared by my process receives and gives up the coloring matter almost instantly as distinguished from other processes which take an appreciable length of time.
  • Natural color effects may be produced in well know manner, such for example as by exposure through color screens with subsequent treatment and manipulation to obtain the desired results.
  • the process of forming a photographic record of lights and shades capable of use as a transfer printing plfate comprises hardening portions 0 adjacent the light affected sensitive content of a photographic emulsion which has been which emulsion exposed to lights and shades, by treating influence of the hardenin agent but to an said emulsion with an ,agent adapted to extent "less than the comp ete neutralization harden said emulsion by reaction with the of said hardening agent. light affected sensitive content of the emul- 29.
  • agent for said hardening agent the relative, I have hereunto set my hand this 23rd day proportions of said hardening and accelerof July, 1919.
  • ating and neutralizing agents being such as I i 10 to control selectively the effective area of v ROBERT JOHN.

Description

motion picture UNITED STATES PATENT OFFICE.
Rosana man, or raw Yonx, 1w. 1, ASSIGNOR 'ro Iconocnnour: courmx or aunarca, me, A coarom'rron or naw You.
PROCESS OF PHOTOGBAPEIG BEPBDDUOTION.
Specification of Letters Patent.
Patented Apr. 12, 1921.
No Drawing. Original application filed May 6, 1916, Serial No. 95,957. Divided and this application filed July as, 1919.
T 0 all whomit may concern.
Be it known that 1, ROBERT J OHN, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented a certain new and useful Process of Photographic Reproduction, of which the following is a specification.
My invention relates to a process of photographic reproduction and has for its object to produce, a printing surface containing a photographic record of lights and dye 01'. ink contact transfer process. An illustrative dye contact transfer process is disclosed in patent to Shepherd and Bartlett, No. 728,310, granted May 19, 1903, for
photographic printing, and an illustrative ink contact transfer process is disclosed in Cassells Cyclopaedz'a of Photography, Cassell & Co. New York, 1912, at page 124, under the title Collotype, it being understood, however, that the processes thus illustrated do not use a printing plate having the novel and beneficial characteristics of the printing plate disclosed herein. Al-
though the preferred method is to obtain the photographic record for the printing surface from a completed negative, it may be obtained by direct exposure, as, for example, in a camera, the details'of which method are disclosed in a copending application for Letters Patent Serial No. 327,890, filed October 2, 1919, for process of photo graphic reproduction directly from a negative. The printing surface when treated with dye or ink also may be used in the same manner as a positive, either for directview, or with reflected light, or with trans mitted light as in a projecting machine.
This application is a division of my co pending application for Letters Patent Serial. No. 95,957, filed May 6, 1916, for photo raphy.
he invention isappllcable to monochromatic ol chromatic, or natural color phop t and in 0th in still photograph hotography.- T e term color is inten ed to include fblack, which sometimes technically is designated as an absence of color.
In the embodiment of my invention tography Serial No. 313,237.
chosen for purposes of illustration, a sensit zed emuls1on such as a silver salt emulsion is exposed to the action of light modified by the lights and shades of the completed negative which it is desired to reproduce. The silver salt emulsion may be carried or mounted on any desired support, either opaque, translucent, or transparent, but
preferably is mounted on a transparent carrier such, for example, as glass-tor a cellulose base, in order that the silver salt emulsion may beexposed to the modified light through its transparent carrier.
The emulsion then is treated by a developing solution containing a hardening or tanning agent which hardens or renders insoluble or unremovable the emulsion adjacent its light affected, light sensitive content, the effect of which agent is controlled or limited selectively by the resence of varying quantities' of a neutra izing agent, after which the unhardened or soluble or removable portions of emulsion are removed in any desired manner, as, for example, by melting with warm water.
The result of the above treatment is the production of what may be termed a printmg surface having novel characteristics and beneficial propertles never before attained.
The most important of the, novel characteristics is a printing or reproducing surface coinprisin granules or great numbers of photograp ically formed, extremely minute, individual protuberances which are distributed and grouped irregularly so as to re resent photographic lights and shades.
he most important of the beneficial properties is that such a printing surface when treated with a dye, ink, or other coloring matter, will absorb or take up or carry the coloring matter within a few seconds, and when thus treated and placed in contact with a substance which is to carry the final reproduction, such for example as a gelatin, will give up its coloring matter practically instantaneously and produce on said gelatin an exact and perfect reproduction.- This speedy result, which is novel and was impossible of attainment before the present invention, is of pr me mportance in the production of mot1on p1cture positives from-motion picture negatives, al-
though the saving of time and the superior results obtainable in still photography also are important. The printing plate or film, moreover, when treated with coloring matter, may be used as a positive if reproductions are not desired.
A sample formula for a developing solution containing a" hardening or tanmng.
agent the efi'ect of which is controlled an limited selectively by the presence of vary in quantities of a neutralizing agent is as f0 ows:
Water 8.5 ozs. gyrogallic acid l1 grs. etol 9 Potassium bromid 4 Sodium carbonate 200 Sodium sulfite 40 to 60 grs.
In the above sample formula the hardening or tanning agent is pyrogallic acid, and the controllin and limiting agent is sodium sulfite which ma be varied in amount selectively within limits to obtain the'desired result. It is well known that pyrogallic acid also is .a developing agent and that sodium sulfite is a preservative adapted to prevent oxidation of the pyrogallic acid in solution. Other hardening and tanning agentsand other neutralizing agents may be used, the above formula representing one developing solution b which the process may be carried out. otassium bromid, for example, also has -a certain controlling and limitin effect. The main difl'erence between t e above sample formula and standard developing formulas is in the amount it is advisable, in order to accelerate the ac- ,7
tion of the 'pyrogallieacid, to use larger quantities of 'an accelerator such, for example, as sodium carbonate or its equivalents than when the emulsion layer is thin or exposed on its face. When larger quantities of sodium carbonate thus are used, it is necessary to increase the amount of sodium sulfite. The above sample formula is for treatment of an emulsion exposed through its transparent. carrier and therefore con-' tains a comparatively large amount of sodium carbonate with an increased amount of sodium sulfite. In order'to obtain the desired printing surface, however, the amount of sodium 'sulfite in the process disclosed herein is much less than would be used in a develop' solution for the usual development oi tfie particular emulsion layer to be treated. Although it is preferable for reasons of convenienceto embody the selectively controlled hardening agent in the developer solution, it may be used separately if desired, by such modification of the developer solution as will prevent such a hardening of the emulsion as will prevent the selective hardening desired.
It is believed that the hardening or tanning effect of the pyrogallic acid exerts its action first adjacent .the so-called latent image, or in other words, on the portions of emulsion adjacent the partlcles of silver salts affected by the exposure light and con verted bv the developer into metallic silver.
,Thus in a silver bromid film, the throwing oil of the bromid from a light afiected silver bromid particle in the developing process, probably reacts with the pyrogallic acid to harden or tan or render insoluble or unremovable the adjacent emulsion. Thus in the embodiment chosen for purposes of-illustration, the reaction products from the chemical efiects of the developer solution, are believed to react with the selectively controlled hardening agent. However this may be, it is necessary for purposes of my invention only either to harden particles of emulsion adjacent light affected particles of the light sensitive content in any desired manner, or in reverse manner to leave unhardened the particles of emulsion adjacent light affected particles of the light sensitive content and harden the remaining emulsion, the essential result being a hardened emulsionsurface corresponding to the lights and shades to be reproduced which will acquire and give up any desired color ,in a comparatively short time. By controlling the hardening or tanning effect of the pyro llic acid as above set forth, only the partlc es of emulsion adjacent thesaid light affected particles of silver salts are hardened, the relative proportions -of the hardening agent (whether or not accelerated by an accelerating agent) and-of the neutrallzlng agent being such as to control selectively the eifcctive area of influence of the hardemn a cut. The unhardened portions, as state a ve, then may be removed in any desired manner as by placing the emulsion in warm waterv which causes the unhardened or soluble portions to soften and melt away from the hardened or insoluble portions so that the hardened emulsion alone will remain in the form of extremely minute, individual protuberances which are distributed and grouped irregularly so as to represent the photographic lights and shades which it is desired to reproduce. It is preferable that Ill . is more convenient to fix, melt, and bleach,
only those portions of emulsion be hardened which are adjacent the carrier for the emulsion, which may be accomplished in various ways, some of which are disclosed in my copending applications for Letters Patent Serial No. 313,239, filed July 25, 1919, for a thin mounted sensitized emulsion, Serial No. 313,24t0, filed July 25, 1919, for process of making a contact transfer printing surface by complementary light, Serial No. 327,891, filed October 2, 1919, for potassium iodid formula for photographic processes, process of using same, and article obtained thereby, Serial No. 332,806, filed October 23, 1919, for process of making a contact transfer printing surface with a colored emulsion, and among which may be mentioned'the exposure of the sensitized emulsion through its transparent carrier and the limitation of the depth to which the rays of exposure light penetrate by having t e actinic rays of the exposure light and the emulsion complementary in color.
f desired the hardened emulsion may be fixed to remove the silver salts unaffected by light, and bleached to remove the black metallic silver. This may be done in well known-manner, andwhile not necessary, is
of advantage as it enables the operator to watch the effect of the coloring matter on the printing surface to which it is applied for carrying out the printing process.
The order of melting, bleaching, and fixing is not important and may be carried out in any order desired, although it generally in the order named. The printing of positives from the printlng surface may be done by'direct contact.
The printing surface is'exposed to the ac-' tion of the desired coloring matter as by placing it in or carrying it through a liq- ,uid color bath. The colored surface then is placed in contact, preferably under some pressure, with the substance on which .the positive is to be made, as by a roller or by a squeegee action. As stated above, the printing surface prepared by my process receives and gives up the coloring matter almost instantly as distinguished from other processes which take an appreciable length of time.
Natural color effects may be produced in well know manner, such for example as by exposure through color screens with subsequent treatment and manipulation to obtain the desired results.
Many modifications of my invention will be apparent to those skilled in the art without departing therefrom or from the scope of the claims, my invention not being limited to the embodiments thereof chosen for the purposes of illustration but consisting of aprocess for forming a printing surface capable of acquiring and giving up a desired color with great rapidity.
Having described one embodiment of my invention, what I claim is:
1. The process of forming a photographic record of lights and shades capable of use asa transfer printing plate, which comprises said hardening and neutralizing agents being such as to control selectively the effective area of influence of the hardening agent but to an extent less than the complete neutralization of said hardening agent. 2. The process specified in claim 1 in which the exposed sensitive emulsion is undeveloped prior to said treatment.
3. The process specified in claim 1 in.
which the hardened portions correspond to the variations of the lights and shades to which the sensitive emulsion has been ex posed.
1. The process specified in claim 1' in which the sensitive content is a silver salt.
5. The rocess specified in claim 1 in which the ardening agent also is a developing agent.
6. The process specified in claim 1 in which the hardening agent is pyrogallic acid.
7. The process specified in claim 1 in which the neutralizing agent also is' a preservative.
8. The process specified in claim 1 in which the neutralizing agent is sodium sul- 9. The process specified in claim 1 in which the hardening agent also is a developing agent and in which the neutralizing agent also is a preservative.
10. The process specified in claim 1 in which the hardening agent is pyrogallic acid and the neutralizing agent is sodium sulfite. 1
11. The process specified in claim 1 in which the sensitive content is developed at the same time the portions of emulsion adjacent the light affected sensitive emulsion are hardened.
12. The process specified in claim 1 in which the sensitive content is developed at the same time the portions of emulsion adjacent the light affected sensitive emulsion are are hardened and in which the photographic record formed then is fixed 14. The process specified in claim 1 m which the sensitive content is developed at the same time the ortions of emulsion adjacent the light a ected sensitive emulsion are hardened and in which the photographlc record formed then is bleached and fixed.
15. The process specified in claim 1 in which said treatment is applied toa photographic emulsion mounted on and exposed through a transparent carrier.
16. The process specified in claim 1 to which is added the step of removing the unhardened portions of emulsion subsequent to said treatment.
17. The process specified in claim 1 in which said treatment is applied to a photographic emulsion mounted on and exposed through a trans arent carrier to which is added the step 0 removing the unhardened portions of emulsion subsequent to said treatment.
18. The process of reproduction which consists in forming on a carrier great numbers of extremely minute individual protuberances which are distributed and grouped irregularly so as to represent an unmodified record of photographic lights and shades, coloring said protuberances, and then placing said protuberances in close contact with the substance on which a reproduction of the lights and shades is desired.
19. The process of reproduction which consists in forming on a carrier great numbers of extremely minute individual protuberances which are distributed and grouped irregularly so as to represent an unmodified record of photographic lights and shades, coloring said protuberances, and then placing said protuberances in close contact and under pressure with the substance on which a reproduction of the lights and shades is desired.
20. The process of reproduction which consists in forming on a carrier great numbers of extremely minute, individual protuberances which are distributed and grouped irregularly so as to represent an unmodified record of photographic lights and shades, coloring said protuberances with liquid coloring matter and then placing said protuberances in close contact with the substance on which a reproduction of the lights and shades is desired,
21. The process of reproduction which consists in forming on a carrier great numbers of photographically formed, extremely minute, individual protuberances which are distributed and grouped irregularly so as to represent an unmodified record of photographic lights and shades, coloring said protuberances, and then placing said protuber ances in close contact and under pressure with the substance on which a reproduction of the lights and shades is desire 22. The process specified in claim 1 in which the lights and shades to which the photographic emulsion has been exposed have been obtained from a photographic negative.
23. The process specified in claim 1 in which the lights and shades to which the photographic emulsion has been exposed have been obtained from a photographic negative to which the step is added of removing the unhardened portions of emulsion subsequent to said treatment.
24. The process specified in claim 1 in which the lights and shades to which the photographic emulsion has been exposed have been obtained from a photographic negative to which the steps are added of removing the unhardened portions of emulsion subsequent to said treatment, and coloring said hardened portions.
25. The rocess specified in claim 1 in which the ights and shades to which the photographic emulsion has been exposed ave been obtained from a photographic negative to which the steps are added of rea moving the unhardened portions of emulsion subsequent to said treatment, coloring said hardened portions, and then placing said colored portions in contact with a substance adapted to take the coloring matter from said hardened portions.
26. The process of forming a photographic record of lights and shades capable of use as a transfer printing plate, which comprises hardening portions of emulsion adjacent the light aflected sensitive content of a photographic emulsion mounted on and exposed through a transparent carrier to lights and shades of a photographic negative, by treatin said emulsion with an agent adapted to arden said emulsion by reaction with the light affected sensitive content of the emulsion, and with a neutralizing agent for said hardening agent, the relative proportions of said hardening and neutralizing agents being such as to control selectively the effective area of influence of the hardening agent but to an extent less than the complete neutralization of said hardening agent, removing the unhardened portions of emulsion, colorlng said hardened portions, and placing said colored portions in contact with a substance adapted to take the coloring matter from said hardened portions.
27. The process specified in claim 26 in which the sensitive content is a silver salt.
28. The process of forming a photographic record of lights and shades capable of use as a transfer printing plfate comprises hardening portions 0 adjacent the light affected sensitive content of a photographic emulsion which has been which emulsion exposed to lights and shades, by treating influence of the hardenin agent but to an said emulsion with an ,agent adapted to extent "less than the comp ete neutralization harden said emulsion by reaction with the of said hardening agent. light affected sensitive content of the emul- 29. The process specified in claim 28 in 5 sion, with an acceleratin agent for said which the sensitive content is a silver salt. 15 hardening agent, and Wit a neutralizing In testimony thatI claim-the foregoing, agent for said hardening agent, the relative, I have hereunto set my hand this 23rd day proportions of said hardening and accelerof July, 1919.
ating and neutralizing agents being such as I i 10 to control selectively the effective area of v ROBERT JOHN.
US313237A 1916-05-06 1919-07-25 Process of photographic reproduction Expired - Lifetime US1374853A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US1417328D US1417328A (en) 1916-05-06 Light film
US313237A US1374853A (en) 1916-05-06 1919-07-25 Process of photographic reproduction
US313286A US1482614A (en) 1916-05-06 1919-07-25 Composition of matter for photographic processes

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US9595716A 1916-05-06 1916-05-06
US313237A US1374853A (en) 1916-05-06 1919-07-25 Process of photographic reproduction

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2650878A (en) * 1949-12-09 1953-09-01 Du Pont Method of producing etched printing plates
US4078492A (en) * 1974-10-04 1978-03-14 Alan D. Levy Making a decorative stained glass effect window shade

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2650878A (en) * 1949-12-09 1953-09-01 Du Pont Method of producing etched printing plates
US4078492A (en) * 1974-10-04 1978-03-14 Alan D. Levy Making a decorative stained glass effect window shade

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