US2895841A - Photographic retouching opaque - Google Patents

Description

United States Patent PHOTOGRAPHIC RETOUCHING OPAQUE William J. Rogers, Rochester, N.Y., assignor to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey No Drawing. Application November 7, 1957 Serial No. 694,924

2 Claims. (Cl. 106-162) This invention relates to photographic retouching opaque.

In the course of making photographic likenesses using conventional photographic equipment it is quite often desirable to retouch the negative prior to making the finished print. In order to satisfactorily retouch the negative, it is often mounted on an illuminated table or stand so that a diifused light enables a retoucher to eliminate spots, background, or the like in order to make the final print more attractive to the subject of the photograph or for other purposes.

In order for an opaque to be satisfactory for retouching purposes, it must be easy to apply, have a good flowing characteristic when applied either by pen or by brush, and a thin coating must be sufliciently opaque to prevent light from passing through it during ordinary photographic printing processes.

In order to provide flexibility to the negative and to permit storage, the opaque must also have good aging characteristics so that upon drying or upon being stored for a period of time, the retouched area will not chip or flake off the negative and the negatives can be reused for printing purposes without requiring a new retouching operation.

In the past, various opaque formulations have been know such as those illustrated in various photographic textbooks and magazines; for instance, the British Journal of Photography, September 29, 1916, on page 533, discloses a retouching medium containing natural resins, turpentine, and the like. Wall and Jordan in Photographic Facts and Formulas," 1940, American Photographic Publishing Company, Boston, Massachusetts, on page 346, discloses a similar retouching medium.

Some of the prior art opaques do not mix easily with water during dilution or have not been satisfactory for scribing so that lines could not be cut smoothly and evently. I have discovered a method of making a satisfactory opaque which has good adhesive characteristics and which is satisfactory for scribing, dilution, aging, and the like.

One object of this invention is to provide a plasticizer for a photographic opaque which permits easy dilution with water. Another object is to provide a plasticizer for photographic retouching media which is satisfactory when the opaque is in a dried-down condition. An additional object is to provide a method of plasticizing photographic opaques with triethylene glycol.

In carrying out my invention, I mix triethylene glycol in the vehicle of the opaque in the amount of from 15% to 25% by weight, depending on the characteristics of the pigment with which the vehicle is mixed. Many pigments used in the manufacture of opaques, need more plasticizer than others due to their physical structure.

The following examples are intended to illustrate my invention but are not intended to limit it to these pigments or to the components other than the trlehylene glycol plasticizer.

The vehicle is added to the pigment in a mechanical mixer. This mixture is then ground on an ink mill untll uniformly smooth.

BLACK OPAQUE Example 2 Vehicle: G

Water 17.40 Triethylene glycol 8.40 Tamol (20% solution) .50 Gum arabic (55% solution) 9.08 Corn syrup 1.00 Phenol .08

36.46 Pigment: Graphite 13.75

Water '1' 6 Tamol .09

Vehicle is added to the pigment in a mechanical mixer and stirred until uniform. It is then transferred to the ink mill and ground until sufliciently smooth.

Variations can be made in the pigments so that opaque materials other than iron oxide or graphite can be used. For instance, white pigments might be used such as zinc oxide titanium dioxide or the like. The only requirement would be that the pigment be sufliciently opaque when combined with the other materials to prevent light from passing through the negative.

Tamol is the sodium salt of sulfonated napthalene formaldehyde condensates.

I claim:

1. A red opaque containing water, corn syrup, the sodium salt of sulfonated naphthalene formaldehyde condensates, gum arabic, phenol, a red pigment and 15-25% by weight of triethylene glycol.

2. A black retouching opaque containing water, the sodium salt of sulfonated naphthalene formaldehyde condensates, gum arabic, corn syrup, phenol, black pigment and 15-25% by weight of triethylene glycol.

References Cited in the file of this patent UNITED STATES PATENTS 1,811,384 Collier June 23, 1931 FOREIGN PATENTS 431,275 Great Britain July 4, 1935 OTHER REFERENCES Gregory: Uses and Applications of Chemicals and Related Materials, vol. II, 1944, page 336.

Claims (1)

1. A RED OPAQUE CONTAINING WATER, CORN SYRUP, THE SODIUM SALT OF SULFONATED NAPHTHALENE FORMALDEHYDE CONDENSATES, GUM ARABIC, PHENOL, A RED PIGMENT AND 15-25% BY WEIGHT OF TRIETHYLENE GLYCOL.