USRE21268E - Photographic backing paper - Google Patents

Description

R iuued Na. 21, 1939 UNITED STATES a Re. 21,268

PATIENT ormcs.

' to Eastman Kodak Company, Rochester a corporation oi! New Jersey No Drawing. Original No. 2,153,130, dated April 4, 1939, Serial No. 101,015, mm 2, 1931.

Application for reissue September 30, 1939,

Serial No. 297,361

3 Claims. (01. 95-5) This invention relates to an improved photographic backing paper and to a photographic cartridge including such backing paper.

The principal object ofthe invention is to pro- 5 vide such a backing paper and cartridge in which the ink used to form the indicia thereon has certain properties of particular utility and advantages of this particular purpose.,

Such indicia are preferably printed by the i0 rotogravure process and an ink suitable for use in that process is, therefore, desirable.

A perfect rotogravure ink should be of low viscosity and have low surface tension; it should .20 Most rotogravu-re inks have been "spirit inks;

that is, inks made with highly volatile organic solvents. These solvents are highly flammable Inks in which and many of them are toxic.

water is used as the solvent have had high surlace tension, and have given proofs of the poorest quality.

" Inks for printing photographic backing paper,

such as for printing the white or black numerals,

etc., on the green or red backing paper which protects photo raphic roll film, have been of two types: water inns and spirit inks. Water inks are composed of a water-soluble dye (or a pigment),

a water-soluble binder, such as gelatin, agaragar, or casein, and water. Spirit inks are composed of a spirit-soluble dye (or a pigment), a

spirit-soluble binder, such as a resin, and an organic solvent; I

Patent 807,458; it is desirable that the backing paper be printed with ink having the'same hygroscopic qualities as the surface'oi the paper; otherwise, under some conditions of storage, particularly under tropical conditions, the nume'rals reproduce themselves photographically on the sensitized emulsion of the fllm. The paper is usually coated or sized, after printing, with an aqueous solution of gelatin, agar-agar, casein, 'etc. when the printing resulting from a watersoluble ink is coatedwith' such an aqueous solution, smearing of the printing often takes place.

In the same way, the printing resulting from spirit-soluble inks smears if the paper is overcoated with a spirit-soluble coating. A water ink cannot be used with a spirit-soluble overcoating, or a spirit ink "with a water-soluble overcoating, because of the resultant difference in hygroscopicity. It has not hitherto been possible to use the rotcgravure process for printing the numerals, etc., on photographic backing pa-' per. The resins used in rotogravure inks are so moisture-resistant, and many oi them are photo- As' has been shown in U. S.

graphically active, causing fogging of the photographic emulsion on the film with which the paper is used. Water inks, such as those described in U.. S. Patent 807,458, will not print by the rotogravure process. I 5 I have discovered that zeinand the'other prolamines, such as gliadin and hordin, which are soluble in. aqueous alcohol, are excellent binders for rotogravure inks, and that such inks are very satisfactory for printing photographic 10 backing papers. The prolamines are insoluble in water alone and in organic solvents alone; hence printing resulting from an ink in which a prolamine is the binder does not smear when coated with either an aqueous solution or a spirit solu- 15 tion. The prolamines are water-susceptible, however, being swelled by moisture in a manner similar, to gelatin or casein. ,Thereiore,

' photographic paper can be printed 'with an ink in which the binder is zein or another prolamine, 20 and then coated with an aqueous solution oi! gelatin or casein, etc. The printing will not smear, and will have the same hygroscopic qualities' as the overcoating. Moreover, the prolaniines are 'not photographically active, so that they do not fog or desensitize the emulsion on photographicfilm -with which the paper may be rolled up.

My novel inks containing a prolamine as a binder iulflll'the requirements 01' a perfect rotoo gravure .ink as well as do ordinary rotogravure inks, and in addition the flammability and toxicity oi. the solvent are much less than those oi! v the solvents ordinarily used in rotogravure inks.

In addition, the use of water as part 01 the sol- 35 vent reduces the cost of the ink.

Among the alcohols and other organic solventswhich may be used with water to dissolve zein or other prolamines are:

water.

A suitable rotogravureink containing min or other prolamine as a bindermay'liave the'iol- 5i lowing general iormulaz Organic solvent(s) parts;.. -50.to Water o 50to10 Y Dye. parts or more 2to, 5

The dye may be 'any'dye that is soluble in the solvent-water mixture and is not photographically active. such, for instance. as:

' place of a dye,' a' pigment, such, for instance. as titanium oxide or carbon black may be used in suitable amount. In inks for printing photographic" backing paper, I prefer to use 5 Spirit Nigrosin N. B. for black ink, and titanium 'oxidei'orwhiteink. v f

I-give below, by .way 01 examples, a number of formulae for inks which I have found satisand by selecting a solvent of the proper boiling Example I Ethyl alcohol a. --c '15 Monomethyl ether of ethylene glycolcc- 75 Zein grams 20 Water cc 50 Nlgrosin'N. B grams 10, .30 V Example}! v Monomethyl etherot ethylene glycol ..-cc 160 zein grams 20 Water cc Titaniumpxide grams 80 scam'mm.

Ethyl 'alcoholcc 300 n-Butyl alcohol cc '.-100.

Zein' grams 60 Nigrosin N. B... -c grams l8 Example Ethyl alcohol cc 320 Zein grams 8 Water--- v Y 80 Nlgrosin N. B grams. 8

I ,E'mmple V Ethyl aieoho1 l '-.cc 150 Monomethyl etheroi' ethylene glycol cc 150 Zein: 'grams 40' water. cc, Nigrosin N B--- grams 0 Example VI r Ethyl alcohol 'cc Monomethyl ether oi ethylene glycol .cc 180 Zein 20 W (l0 Nis'rosin H. B"; "ms" 10 "States is:

:matter, and overcoated with a colloid,-su 7 per having the .property that, when the indicia sitized layer carrying indicia composed of a non v lzarnple vll Monomethyl ether oi ethylene glycol cc 4N i Water V c 1M Titanium o'xide "gramm m Example vm Et alnnhnl no 49o Zein. 3 grams 5G 10 Water 100 Titanium oxide grams 300 What! claim as myiinvention and desireto' be secured by Letters Patent of the United 1..Photographic paper carrying indiq cia composed ot-a non-hardened prolamine and factory The printing and drying characteristics coloring matter, overcoated with a colloid.

so may be controlled by the concentration of zein 2. Photographic backing papercarrying indicia composed oi'non-hardenedrei-n'and coloring matter, over-coated with a colloid.

3. An un'sensitized, opaque, photographic back ing paper carrying on one surface indicia composed oi 'a non-hardened prolamine and coloringbearing surface is maintained in contact with a will'not 'aflect the emulsion. I g

4. A roll film cartridge comprising inter-rolled strips of film having a sensitized layer and of unsensitized backing paper, that surface. of the backing paper which is in contact with the senphotographically sensitive emulsion, the in'dicia hardened prolamine and coloring matter an being overcoated with:a colloid.-

5. Photographic backing paper carrying indicia composed-of a non-hardened prolamine and coloring matter, overcoated with a water-soluble colloid.

6.Photographic backing paper carrying i'ndi- I -cia composed of non-hardened zein and .coloring matter, overcoated with a water-soluble col- 74 An unsensitized, opaque; photographic 45 backing paper carrying on one surface indicia composed of a non-hardened prolamine and colorlng matter, and overcoated with a water-soluble colloid, such paper having the'proper y that. Y

when the indicia-bearing sui'ace is maintained in :50 contact with a photogaphicall'y sensitive emul-. sion, the indicia will not aflect the emulsion.

8. A roll iilm cartridge-comprising inter-rolled strips of fllm having a sensitized layer" and of unsensitized backing paper. that surface of the 55 backing paper which is in contact with the sen-- 'sitized layer carrying indicia of anon; [hardened prolamine and coloring matter and beinl overcoated with a water-soluble colloid.