US1482614A - Composition of matter for photographic processes - Google Patents

Description

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' STATES QDFFHQEO RQBERTJUHN, GE NEW YORK, N. Y., ASSIGNOR T0 DAYLIGHT FILM CtlRPQELATIQH, A CORPOBATION OF NEW YORK.

CGMPOSITION 0F MATTER FOR PHOTUGRATPHIC IPBDCESfiEQ.

Ho Drawing. Original application filed may a, 1916, Serial Ito. 95,535? Divided and this application filed July 2Y5, 1919.

To all whom it may concern:

Be it known that l, Bonner JOHN, 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 Composition of Matter for Photographic Processes, of which the following is a specification.

My invention relates to a composition of matter for photogra hic processes and has for its object to pro uce a printing surface containing a photographic record of lights and shades from W ich copies can be made by a dye or 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 Cyclopaedia of Photography, Cassell & 00., New York, 1912, at page 1% under the title Collotype, it being understood, however, that the processes thus illustrated do not disclose a printing plate having the novel and beneficial characteristics of the printing plate obtained by the-use of the composition of matter disclosed and claimed herein. Although the preferred method is to obtain the'photographic record for the printing surface from a completed negative, it 1 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 photographic 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 direct view, or with reflected light, or with transmitted light as in a projecting machine. I

This application is a division of my copending application for Letters Patent Serial No. 95,957, filed May 6, 1916, for

photography.

The invention is applicable to monochromatic, polychromatic, or natural color photography both in still photogra by and in motion picture photography. 1e term color is intended to include black, which" sometimes technically is designated as an absence of color.

Serial lilo. 813,238.

lln the embodiment of my invention chosen for purposes of'illustration, a sensitized emulsion 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 or a cellulose base, in order that the the silver salt emulsion may be exposed to the moditied 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 adected, light sensitive content, the effect of which agent is controlled or limited selectivelg by the presence oi varying quantities o a neutralizin agent, after which the unhardened or soluble or removable portions of emulsion are removed in any des1red manner, as, for example, by melting with warm water.

The result of the above treatment is production or what may he termed a printing surface having novel characteristics and beneficial properties never before attained. I

The most important of the novel characteristics is a printing or reproducing surface comprisinggranules or great numhers of photo raphically formed, cntremelyminute, in ividual protuherances which are distributed and grouped irregularly so as to represent photographic lights and shades.

The most important. of the beneficial properties is that such a printing surface when treated with a dye, inlr, or other coloring matter, will absorb or take up or carry the coloringmatter 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 prime importance in the production of motion picture posiilll Water a; 8.5 ozs. P rogallic acid l1 grs.

etol 9 grs. Potassium bromide -s 4 grs. Sodium carbonate 200 grs.

Sodium sulphite "40 to 60 grs.

In the above sample formula the hardening ortanning agent is pyrogallic acid, and the controlling and limiting agent is sodium sulphite which may be: varied in amount selectivelywithin limits to obtain the desired result. It is well known: that pyrogallic acid also is a developing agent and that sodium sulphite is a preservative adapted toprevent'oxidation of the pyrogallic acid in solution.: Other hardening and tanning agents and other neutralizing agents may be used, the above formula representing one developing solution by which the process may be carried out; Potassium bromide, for example, also has a certain controlling and limiting effect. The main difference betweenthe above sample formula and standard developing formulas is in'the amount of sodium Csulphite used. ln

standard formulas the amount of sodium sulphite used is so greatly in excess of the amount used in the above sample formula that. the tanning or hardening effect of the pyrogallic acid is'entirelv neutralized or overcome. In the sample formula, the sodium sulphite merely controls and limits the hardening effect of the pyrogallol. It *is of course understoodyby those skilled in the art that when a thick layer of emulsion is treated, or when the exposure is through the transparent carrier, it is advisable, in order to accelerate the action of the pyrogallic acid, 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 sulphite. The above sample formula is for treatment of an emulsion exposed through its transparent carrier and therefore contains a comparatively large amount of sodium carbonate with an increased amount of sodium sulphite. In order to obtain the dethe selectlve hardening desired.

It is believed that the hardening or tanning effect of the pyrogallic acid exerts its action first adjacent the so-called latent ima e, or in other words, on the portions of emu sion adjacent the particles of silver salts affected by the exposure light and converted by the developer into metallic silver. Thus in a silver bromide film, the throwing off of the bromide from a light affected silver bromide particle in the developing process, probably reacts with the pyrog ic acid to harden ortan or render insoluble or unremovable the adjacent emulsion. Thus in the embodiment chosen for purposes of illustration,'the reaction roducts from the chemical effects of the eveloper 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 afiected particles of the light sensitive content and harden the remaining emulsion, the essential result being a hardened emulsion surface corresponding to the lights and shades to be reproduced which will acquire and give up any desired color in a com aratively short time. By controlling the liardening or tanning effect of the pyrogallic acid as above set forth, only the particles of emulsion adjacent the said 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 neutralizing agent being such as to control selectively the effective area of influence of the'hardening agent. The unhardened portions, as 'stated above, then may be removed in any desired manner as by placing the emulsion in warm water 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 measleonly 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 coending applications for Letters Patent erial No. 313,239, filed July 25, 1919, for a thin mounted sensitized emulsion; Serial No. 313,240, filed July 25, 1919, for proeess of making a contact transfer printing surface by complementary light; Serial No. 327,891, filed-October 2-, 1919, for potassium iodide 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 ma 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 the actinic emulsion complementary in color.

If desired the hardened emulsion may be fixed to remove the silver salts unadected by light, and bleached to remove the black metallic silver. This may be done in well known manner, and While not necessary, is of advantage as it enables the operator to watch the sheet 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 ma be carried out in any order desired, althoug it enerally is more convenient to fix, melt, an bleach, in the order named.

, The printing of positives from the printing surface may be done by direct contact. The printing surface is exposed to the action of the desired coloring matter as by placing it in or carrying it through a liquid 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, asby a roller by a squeegee action. As stated above, the printing surface prepared by my process receives and gives up the coloring matter almost instantl as distinguished from other processes which take an appreciable length of time.

Natural color effects may be produced in well known manner, such for example as by exposure through color screens with subsequent treatment and manipulation to obtain the desired results.

Many modifications of m invention will be apparent to those ski led in the art without departing therefrom or from the scope of the claims, my invention not being limited to the embodiments thereof chosen i'or purposes of illustration but consisting of a composition of matter for forming a printing surface capable of acquiring and giving up a desired color with great rapidity.

rays of the exposure light and the By the term metol in this case is meant monomethylparamidophenol sulphate or its equivalents. I

Having described one, embodiment of my invention, what I claim is:

1. A developing and hardenin composition of matter containing an emu sion hardening andsilver salt developing substance and a substance partially but not entirely neutralizing the emulsion hardening effect of said developing and hardening substance in such amount as to ,permit only a selective areaof hardening.

2. A developing and hardening composition of matter containing pyrogallic acid and a substance partially but not entirely neutralizing the-emulsion hardening effect of said pyrogallic acid in such amount as to permit only a selective area of hardening.

3. A developing and hardening composition of matter containing pyro allic acid and sodium sulphite in which t e amount of sodium sulphite is suflicient only to control but not eliminate the hardening efiect or the pyrogallic acid.

4. A gelatin hardening composition of matter containing an emulsion hardening substance and a substance partially but notentirely neutralizing the emulsion hardening etl'ect of said hardening substance in such amount as to permit only a selective area of hardening.

5. An emulsion hardening composition of matter containing pyrogallic acid and a substance partially but not entirel neutralizing the emulsion hardening eilect of said pyrogallic acid in such amount as to permit only a selective area of hardening.

6. A developing and hardening composition of matter containing water, pyrogallic acid, metol, otassium bromide, sodium carbonate, and sodium sulphite in which the amount of sodium sulphite is sufiicient only to control but not eliminate the hardening effect of the pyrogallic acid.

A developing and hardening composition of matter containing grs. Sodium sulphite 40 to grs.

8. A developing and hardening composition containing pyro allic acid, sodium sulfite and sodium car onate, in which the sulfite is present onl in suilicient quantity to control but not e iminate the hardening effect of the pyrogallic acid.

9. A developing and hardenin composition containing pyro llic aci sodium sulfite and sodium car onate, in which the ratio by weight on the dry basis, or carbonate to sulfite is greater than 3:1 and in which the sulphite is present only in sufiicient quantity to control but not eliminate the hardenin efiect of the pyrogallic acid.

10. A deve oping and hardenin com osition containing pyrogallic aci so ium sulfite and sodium carbonate, in which the ratio by weight, on the dry basis, of carbonate to pyrogallic acid is about 10:1

and in which the sulphite is present only in in sufficient quantity to control but not eliminate the hardening effect of the pyrogallic acid.

In testimony that-I claim the foregoing,

I have hereunto set my hand this 23rd day 15 of July, 1919.

ROBERT JOHN.