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Publication numberUS3666470 A
Publication typeGrant
Publication dateMay 30, 1972
Filing dateJul 3, 1969
Priority dateJul 4, 1968
Also published asDE1933844A1, US3779766
Publication numberUS 3666470 A, US 3666470A, US-A-3666470, US3666470 A, US3666470A
InventorsNobuo Tsuji, Takushi Miyazako, Fumihiko Nishio, Tatsuya Tajima, Yoshinori Tsuchiya
Original AssigneeFuji Photo Film Co Ltd
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Photographic printing element containing fluorescent dye
US 3666470 A
Abstract
There is disclosed a method for developing a photographic element which comprises developing a photographic element having photographic layers in a developer containing a water-soluble fluorescent whitening agent, wherein at least one of said photographic layers contains a particular water-soluble polymer or copolymer. In addition, the instant invention also extends to the photographic printing element employed in the method recited above.
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Description  (OCR text may contain errors)

y 1972 NOBUO TSUJI ETAL 3,666,470

PHOTOGRAPIIIC PRINTING ELEMENT CONTAINING FLUORESCENT DYE Filed July 5, 1969 RELATIVE NNUJ 4 UT 9? bi 5 I Z 24 WATER WASHING TIME INVENTORS NOBUO TSUJI, TATSUYA TAJIMA TAKUSHI MIYAZAKO, YOSHINORI TSUCHIYA FUMIHIKO NISHIO ATTORNEYS United States Patent 3,666,470 PHOTOGRAPHIC PRINTING ELEMENT CONTAINING FLUORESCENT DYE Nobuo Tsuji, Tatsuya Tajima, Takushi Miyazako, Yoslunori Tsuchiya, and Fumihiko Nishio, Kanagawa, Japan, assignors to Fuji Photo Film Co., Ltd., Ashigara-Kamigun, Kanagawa, Japan Filed July 3, 1969, Ser. No. 838,812 Claims priority, application Japan, July 4, 1968, 43/ 46,708 Int. Cl. G03c 1/92 US. Cl. 96-82 9 Claims ABSTRACT OF THE DISCLOSURE A photographic printingelement containing a watersoluble fluorescent whitening dye and a water-soluble polymer of an N-vinylamide compound.

The present invention relates to a photographic printing element and in particular to a photographic printing element having improved whiteness in the absence of a matt surface.

Hitherto, in order to improve the whiteness of nonimage (blank) portions of a printed photographic printing element, it has been attempted to incorporate a fluorescent whitening dye, which emits a purple or a blue fluorescence by absorbing ultraviolet rays, in photographic layers, such as a baryta layer, an undercoating, a light-sensitive emulsion layer, a protective layer applied to a support or an image receiving layer of a printing element for diffusion transfer photography (hereinafter, these layers are called photographic layers). Water-soluble polyvinyl pyrrolidone in one of these photographic layers, and watersoluble poly-N-vinyl-S-methyl-2-oxazolidinone have also been incorporated in one of these layers for this purpose.

However, the conventional method of incorporating a fluorescent whitening dye has the drawback that, since the fluorescent whitening dye is not absorbed on the colloidal component of photographic layers, such as gelatin, although the fluorescent dye has a direct dyeing afiinity to fibers, the intensity of fluorescence emitted from the fluorescent whitening agent incorporated in photographic layers is weaker than the case where the same fluorescent dye is absorbed on fibers, and suflicient whitening effect is not obtained. Furthermore, the greater part of the fluorescent whitening dye present in the photographic layer is removed in the water-washing stage after development, which severely weakens the whitening effect.

The aforesaid method of incorporating water-soluble poly-N-vinyl-S-methyl-Z-oxazolidine or water-soluble polyvinyl pyrrolidone in the photographic layer has the drawback that, although the whitening effect is higher as the degree of polymerization of the polymer to be employed is higher, when a polymer having a high degree of polymerization is employed, the surface of the photographic printing element is matted.

Therefore, an object of the present invention is to pro* vide a photographic printing element having improved whiteness by employing a water-soluble fluorescent whitening dye without the accompaniment of the aforesaid drawbacks.

Another object of the present invention is to provide a water-soluble high molecular weight compound to be employed together with a fluorescent'whitening dye for improving the whiteness of a photographic printing element by being incorporated in a photographic layer of the element without being accompanied by the aforesaid drawbacks.

We have found that the above objects can be achieved by the incorporation of a fluorescent whitening dye and a water-soluble high molecular weight compound, which compound is prepared by polymerizing an N-vinylamide compound represented by the formula CH =CHNR COR wherein R represents methyl or ethyl and R represents hydrogen, methyl or ethyl, or copolymerizing the above monomer with another comonomer, in at least one of the photographic layers of a photographic printing element, such as, a baryta layer, an undercoating, a light-sensitive emulsion layer, a protective layer, or a diffusion transfer imagereceiving layer applied on a support.

The water-soluble fluorescent whitening dye (or fluorescent brightening agent) to be employed in the present invention is one which emits a blue-purple fluorescence (of wavelengths of 43 0-470 mu.) by absorbing ultraviolet rays. As fluorescent whitening dyes which may be employed in the present invention, there may be mentioned those known water-soluble fluorescent dyes having a direct dyeing aflinity, such as diaminostilbene dyes, benzidine dyes, triazole dyes, imidazole dyes, and imidazolone dyes. Specific examples of such fluorescent whitening'dyes are as follows:

Diaminostilbene fluorescent dyes (a) Compounds of the formula QCEECH-QNHQIE] wherein X, Y, X, and Y each represents -NHC H --NHC H SO Na, 0H, NH NHCH CH SO Na, --OCH CH OH, or -OC,H and n. represents 5 to 100.

CdHgNHCONH NHCONHC|H 1 SOaNa SOaNa n wherein n represents 5 to 100.

Benzidine fluorescent dyes (a) Compounds of the formula SOaNa SOaNa wherein R and R' each represents H, -CH or OCH (b) Compounds of the formula wherein R represents H, -CH OCH Triazole fluorescent dyes N iNa S'OaNa N s SOINB (b) N R and R each represents a hydrogen atom, an alkyl or Naoas hydroxyalkyl group having 1-12 carbon atoms, a sulo- N CH=OHQ alkyl group (or an alkali metalsalt or ammonium salt thereof), a canboalkyl group (or an alkali metal oram 503m, monium salt thereof), an aralkyl group, an aryl group having 6-18 carbon atoms," a hydroxycarboxy or sulfonic acid derivative of the aryl group, or an, alkali metal or (6) ammonium salt of the aryl group, a cycloalkylgroup having 6-10 carbon atoms, or a substituted cycloalkyl group;

A represents an alkylene group having 4-5 carbonatoms Compounds of the formula or an alkylene group having a hetero atom or hetero N N atomic group; Y represents an alkylene group having 2-10 carbon atoms, a substituted alkylene group, an alkylene C @343; group having 6-18 carbon atoms, or a substituted alkylene group; Z represents adivalent hetero armor. atomic s Q Na S osNa B group; m is 0 or 1; and M represents an alkali metal'or aml monium group. a v

z (7) These fluorescent whitening dyes which may be em ployed in the present invention are well-known to those wherein R represents H, CH C H OCH 0 skilled in the art and are readily commercially available -SO Na and R represents H, CH or by the trade names of Blankophor (Farbenfabriken' Imidazole fluorescent dyes Bayer A. G.), Leucophor (Geigy Chemical CorpJ, CHZCHZOH Tinopal (Sandoz A. G.), Uvitex (Ciba'Ltd.),'"Kaya-' Imidazolone fluorescent dye phor (Nippon Kayaku K. K.), Potamin White .(Dupont), Whitex (Sumitomo Chemical IndustriesCoJ', and (Honshu Chemical Co.). Forexample, Blanl 6 NE NH ophor B is a fluorescent whitening agent corresponding to S We Formula 1 and Blankophor R corresponds to Formula 2. i f i A (3) 40 The Water-soluble high molecular weight compound The above dye is disclosed in applicants Japanese patent used in this invention may be either a homopolymer of an application No. 22,756/ 67. N-vinyl amide represented by the general formula High molecular weight compounds having at least one of CH2=CHNR1CoR2 7 V the repeating units represented by general Formulas 7 W (9) and (10) or a copolymer of such N-vinylamide and-another tno'n Compounds of the formula omer such as acry1am ide,'methacry1amide, 'N-methylacryl wherein R and R each represents a hydrogen atom, an amide, N,N-dimethylacrylamide, N,N- diethylacrylamide, alkyl group having 1-3 carbon atoms, an aryl group havacryloyl morpholine, N-methylolacrylafiiide; N hyiiroxy ing 6-42 carbon atoms, a. hydroxyalkyl group having 2-4 ethylacrylamide, acrylic acid, methacrylic acid; methyl carbon atoms, a substituted hydroxyalkyl groupfa sulfoacrylate, hydroxethyl 'acrylate, acrylonitrile', l-vinyl-Q alkyl group having 1-4 carbon 3101115, an alkali metal salt methyl'm idazole, N-vinylpyriding, 4-viny1pyridine; N- thereof, or an ammonium salt; R represents a halogen vinylpyn'olidone, N m l l idi i i g ql atom, CR, SR, I tam, N-vinyl-5-methyl-2-oxazolidinone, vinyl acetate,

if maleic anhydride, sodium 'p-vinylberizenefsulfonate,or

. R i methyl vinyl ether. V I I x The aforesaid N-vinyla mide:compoundrepresented by 35 the above general formula may be easily prepared by IQ? acting the corresponding N-alkylacyl compound represented by the general formula R CONHR and acetylene in an autoclave in the presence of an alkali catalyst.

As examples of the N-vinylamide compound, there may be mentioned N-vinyl-N-methylformamide (boiling point 73 C. at a pressure of 50 mm. Hg), N-vinyl-N- methyl acetamide (boiling point 63 C./ 17 mm. Hg), N- vinyl-N-methylpropionamide (boiling point 75 C./ 17 mm. Hg), N-vinyl-N-ethylformamide (boiling point 81 C./50 mm. Hg), and the like.

The desired polymer may be obtained by dissolving the above N-vinylamide compound in a solvent such as water, an alcohol, benzene, ligroin or the like and conducting the polymerization in a nitrogen gas stream at a temperature of about 40-100 C. in the presence of a catalyst such as hydrogen peroxide, potassium persulfate, 2,2-azobisbutyronitrile, or the like.

In the case of preparing the copolymer of this invention, it is preferable for improving the whitening effect that the proportion of the aforesaid comonomer be less than 20 mole percent of the total amount of copolymer.

In order to obtain the desired whitening effect, higher molecular weight polymers are desirable for use in the present invention, and the molecular weight is preferably in the range of about 50,000500,000 (intrinsic viscosity 0.2-1.5 in an aqueous solution at 30 C.). Particularly useful are polymers having a molecular weight of about 100,000400,000 (intrinsic viscosity 0.5-1.2 in an aqueous solution at 30 C.). However, polymers possessing molecular weights above and below these ranges may be employed.

When using the aforesaid conventional N-vinylpyrrolidone polymer, if the molecular weight thereof is higher than 100,000, and particularly if it approaches about 360,000, the miscibility of the polymer with gelatin is degraded, whereby the surface of the photographic printing paper tends to be severely matted. On the other hand, the aforesaid N-vinylamide polymer of this invention having a molecular weight of higher than 100,000 shows a good miscibility with gelatin and moreover even if the molecular weight thereof is over 300,000, very little lack of miscibility occurs, provided the amount of the polymer employed is not excessive, that is, not more than about 60% by weight.

There exists no particular limitation on the amount of of the N-vinylamide polymer or copolymer of the present invention provided sufficient polymer is present to obtain the desired whitening effect. In general, at least by weight of the polymer based upon the total weight of polymer and gelatin binder is desirable to obtain significant whitening eifect. However, since the use of an excess amount of the polymer does not substantially increase the whitening effect over a value achieved by about 40% by weight, and in fact reduces miscibility with gelatin and causes a degradation of the quality of the image and is in addition uneconomical, the preferred amount of polymer employed is about 5-40% by weight. Most preferably, the amount employed is about 15-25% by weight.

As mentioned above, the photographic layers of the photographic printing element of this invention include any of a silver halide emulsion layer, a baryta layer, an undercoating, a protective layer applied to a support such as paper, synthetic resin film, a glass plate or a metal plate and an image receiving layer for a diffusion transfer printing element applied to the support. The fluorescent whitening dye and the water-soluble high molecular weight compound may be incorporated in any one of the above photographic layers to provide the desired effect. Further, the water-soluble high molecular weight material may be incorporated in a different photographic layer than the layer containing the fluorescent whitening dye.

Also, the invention has been exemplified above in terms of using gelatin as the binder. However, other binders such as synthetic resins may be similarly employed in the present invention.

By the present invention, a photographic printing element providing the same or a superior effect than con ventional photographic elements containing an N-vinylpyrrolidone polymer or an N-vinyl-S-methyloxazolidione polymer is provided without resulting in the matting of the surface encountered in the conventional methods.

The invention will be explained more practically based on the following examples.

EXAMPLE I To a gelatino silver halide emulsion containing 50 g. of gelatin and 20 g. of silver chlorobromide (containing 30 mole percent silver bromide) were added 0.5 g. of the fluorescent whitening agent Blankophor BUP (trade name of Farbenfabriken Bayer A. G.) and 10 g. of an N vinyl N methylacetamide homopolymer having an intrinsic viscosity of 1.05, 0.58, or 0.32 in an aqueous solution of 300 C. Then, after adding to the emulsion formaldehyde as a hardening agent and saponin as a wetting agent, the resulting silver halide emulsion was applied to a photographic baryta paper of g./sq. meter to provide a photographic paper. The photographic paper thus prepared was processed in a developer and a fixing solution having the following compositions respectively;

Developer: G. Metol (p-methylaminophenol sulfate) 1.0 Sodium sulfite (anhydrous) l5 Hydroquinone 4 Water to make, 1 liter.

The sample was washed with running water of 15 C. for 1, 5, or 24 hours.

The photographic paper thus prepared and processed was tested for intensity of fluorescence, the results of which are shown in the figure of the accompanying drawing. In the figure, there is shown the relation between the water-Washing time and the relative intensity of fluorescence, which was a relative value when the whiteness of the surface of the photographic paper itself was assumed to be 25. In the figure, curve 1 stands for the results in the case of using the high molecular weight compound having an intrinsic viscosity of 1.05, curve 2 for the case of using the high molecular weight compound having an intrinsic viscosity of 0.58, and curve 3 for the case of using the high molecular weight compound of an intrinsic viscosity of 0.32. Curve (a) in the figure represents a con trol run, using a paper prepared as above, but having incorporated therein only the fluorescent whitening dye and not the water-soluble high molecular weight compound.

As will be understood from the results shown in the figure, the intensity of fluorescence of the photographic papers of this invention was remarkably higher than the result of the control sample shown by curve (a) and among the photographic papers of this invention, the sample having the water-soluble high molecular Weight material having a higher molecular weight gave higher intensity of fluorescence. Moreover, even though the watersoluble high molecular weight compound having a higher molecular weight was employed, the surface properties of the photographic paper were not injured. Also, very little reduction in whiteness by water washing was observed.

EXAMPLE II To one liter of a baryta coating dispersion having the following composition were added one gram of Blankophor EU? as the fluorescent whitening dye and g. of an N-vinylsN-methylformamide polymer having an intrinsic viscosity of 1.05 (molecular weight of 40,000):

Water to make, 1 liter.

The baryta coating composition was applied to a paper in a thickness of 100 g./ sq. meter. To the baryta coated paper was applied a gelatino silver halide emulsion containing 50 g. of gelatin and 20 g. of silver chloride and having added thereto formaldehyde as a hardening agent and saponin as a wetting agent followed by drying.

The photographic paper thus prepared was processed as in Example I and the result was compared with a control paper wherein no -N-vinyl-N-methylformamide polymer was incorporated in the baryta layer. The results showed that the whiteness of the surface of the photographic paper of this invention was much better than the control case. Moreover, the whitetness of the photographic paper of this invention was not reduced by water washing.

EXAMPLE HI After adding formaldehyde as a hardening agent and saponin as a wetting agent to a gelatino silver halide emulsion containing 20 g. of silver chlorobromide (60 mole percent silver bromide) per 50 g. of gelatin, the resulting silver halide emulsion was applied to a baryta coated paper of 150 g./sq. Before drying the silver halide emulsion layer, an aqueous solution containing 0.7 g. of Whitex BF (trade name of Sumitomo Chemical Industries Co.) as a fluorescent whitening dye, 8 g. of the N-vinyl-N-methylformamide having an intrinsic viscosity of 0.90, 3 ml. of formalin, 6 ml. of a 6% methanol solution of saponin, and one liter of Water was applied to the silver halide emulsion layer in a setting state and dried. The photographic paper thus prepared was processed and dried as in Example I and the results were compared with a control paper having no N-vinyl-CN-methylformamide polymer added. The results showed that the whiteness of the surface of the photographic paper of this invention was higher than the control case. Also, the whiteness of the photographic paper of this invention was not reduced by water washing.

EXAMPLE 1V After adding 0.5 g. of Kayaphor S (trade name of Nippon Kayaku K. K.) as a fluorescent whitening agent and formaldehyde as a hardening agent and saponin as a wetting agent to a gelatino silver halide emulsion containing 20 g. of silver iodobromide (1.5 mole percent silver iodide) to 50 g. of gelatin, the resulting emulsion was applied to a baryta coated paper of 150 g./ sq. meter. To the silver halide emulsion layer in a setting state before drying was applied an aqueous solution containing 20 g. of gelatin, 8 g. of the N-vinyl-N-methylpropionamide polymer having an intrinsic viscosity of 0.98, 3 ml. of an aqueous 30% solution of formalin, 6 ml. of a 6% methanol solution of saponin, and one liter of water followed by drying to provide a protective layer.

The photographic paper thus prepared was processed and dried as in Example I and the results were compared with a control having no added N-vinyl-methylpropionamide polymer in the protective layer. The results showed that the whiteness of the surface of the photographic paper of the present invention was much better than'in the control. Moreover, the whiteness was not reduced by water washing after processing.

EXAMPLE V To the baryta coating composition as shown in Ex ample II was added 12 g. of an N-vinyl-N-methylformamide polymer having an intrinsic viscosity of 0.85 and the resulting composition was applied to a paper of ,100 g./sq. meter followed by drying. To the baryta layer was applied a gelatino silver halide emulsion containing 20 g. of silver chlorobromide (30 mole percent silver bromide) to 50 g. of gelatin. and having added thereto formaldehyde as a hardening agent and saponin as a wetting agent. Further. to the silver halide emulsion layer in a setting state before drying was applied an aqueous solution containing 20 g. of gelatin, 1 g. of the benzidine fluorescent whitening dye of the formula (3H H V 0 (FBI QQ S0 Na -SOaNa 3 ml. of an aqueous 30% solution of formalin, 6 mil of a 6% alcohol solution of saponin, and one liter of water followed by drying.

The photographic paper thus prepared was processed and dried as in Example I and the results were compared with a control having no added N-vinyl-tN-methylform amide polymer. The whiteness of the photographic paper of this invention was much better than the control and also was not reduced by water washing after processing.

EXAMPLEVI After adding to one liter of the baryta coating composition as shown in Example H one gram of the imidazolone fluorescent whitening dye represented by the formula as the fluorescent whitening agent, the resulting composition was applied to a paper of 100 g./s'q. meter followed by drying. Thereafter, a gelatino silver'halide emulsion containing 20 g. of silver iodobromide (1.5 mole percent silver iodide) to 50 g. of gelatin having added thereto 12 g. of a copolymer having :a mole ratio of N-vinyl-N-methylacetamide to acrylamide of 9:1 and an intrinsic viscosity of 0.85, formaldehyde as a hardening agent, and saponin as a wetting agent was applied to the baryta layer followedbydrying. I

The photographic paper thus prepared was processed and dried as in Example I and the results were compared with a control wherein the aforesaidc'opolymer was not incorporated in the emulsionflayenThe results showed that the whiteness of the surface of the photographic paper of this invention was much better than the "control case and was not reduced by water washing after processmg. p

EXAMPLE VII To one liter of a aqueous 5% gelatin solution containing colloidal nickel sulfite were aded 0.5 g. of .Tinopal G (trade name of Sandoz A. G.) as a fluorescent whitening dye and 1 2 g. of a copolymer hayinga mole ratio of N-vinyl-N-methylformamide "to methacrylamide of 9:1 and an intrinsic viscosity of 0:75 andthe' resulting solution was applied to a paper of g. /sq. meter. On the layer thus formed was applied a stripping layermainly consisting of sodium alginate, to' provide a diifusion transfer image receiving element.

The image receiving element thus prepared was closely placed on a light-sensitive layer having a silver halide emulsion layer which had been exposed. The assembly was passed through a diffusion transferring deviceand a developer and the image receiving element was stripped from the light-sensitive elemen't after- 30 seconds; The results were compared with 'a control wherein the aforesaid copolymer was not employed. The results showed that the whiteness of the white background. portions of the positive image was better than the control. v

9 EXAMPLE VIII To a gelatino silver halide emulsion containing 20 g. of silver chlorobromide (30 mole percent silver bormide) to 50 g. of gelatin was added 10 g. of an N-vinyl-N-methylacetamide polymer having an intrinsic viscosity of 1.05 and the resulting silver halide emulsion was, after the addition of formaldehyde as a hardening agent and saponin as a wetting agent, applied to a baryta coated paper of 150 g./sq. meter. The photographic layer was developed in the developer of Example I, but having added thereto 0.7 g./liter of Blankophor BUP and then fixed, washed with water and dried as in Example I. The results were compared with a control where no N- vinyl-methylacetamide polymer was added to the silver halide emulsion layer. The whiteness of the surface of the photographic paper of this invention was better than the control and was not reduced by water after processing.

What is claimed is:

1. A photographic printing element having photographic layers, at least one of said photographic layers containing a water-soluble fluorescent whitening dye and a water-soluble member selected from the group consisting of a polymer and a copolymer of a compound represented by the formula CH2=CH wherein R represents a radical selected from the group consisting of methyl and ethyl and R represents a radical selected from the group consisting of hydrogen, methyl and ethyl.

2. The photographic printing element as claimed in claim 1 wherein said water-soluble fluorescent whitening dye is selected from the group consisting of a diaminostilbene fluorescent dye, a benzidine fluorescent dye, a triazole fluorescent dye, an imidazole fluorescent dye and an imidazolone fluorescent dye.

3. The photographic printing element as claimed in claim 1 wherein said compound is selected from the group consisting of N-vinyl-N-methylformamide, N-vinyl-N- methylacetamide, N-vinyl N-methylpropionamide, and N vinyl-N-ethylformamide.

4. The photographic printing element as claimed in claim 1 wherein said photographic layer is selected from the group consisting of a baryta layer, an undercoating layer, a light-sensitive silver halide emulsion layer and a protective layer.

5. The photographic printing element as claimed in claim 1 wherein said photographic layer is a diffusion transfer image receiving layer.

6. A photographic printing element as claimed in claim 1 wherein said member is a homopolymer.

7. A photographic printing element as claimed in claim 1 wherein said member is a copolymer of said compound and another vinyl monomer.

8. A photographic printing element as claimed in claim 1 wherein the water-soluble fluorescent dye and the watersoluble member selected from said group are in different photographic layers of said element.

9. A photographic printing element as claimed in claim 1 wherein said water-soluble member has a molecular weight of about 50,000-500,000.

References Cited UNITED STATES PATENTS 3,269,840 8/1966 Pattyn et al. 9682 FOREIGN PATENTS 22,065 7/1964 Japan 95-82 245,729 7/1967 Germany 9682 M RONALD H. SMITH, Primary Examiner U.S. Cl. X.R.

96-85, 87 R, 76 R, 114; 11733.'5 T

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3873317 *May 11, 1973Mar 25, 1975Fuji Photo Film Co LtdImage receiving materials with whitening agents for a silver salt diffusion transfer process and method of preparing the same
US4526853 *Oct 14, 1983Jul 2, 1985Konishiroku Photo Industry Co., Ltd.Silver halide color photographic material comprising emulsion layer, brightening agent layer, ultraviolet absorber layer
US6329438Oct 4, 2000Dec 11, 2001Medtronic Xomed, Inc.Introducing rinsing solution into pores of sponge material; and changing hydrostatic pressure of the rinsing solution in pores of sponge material
US20130216947 *Feb 6, 2013Aug 22, 2013Tatsuya SusukiChemical coating composition for forming a laser-markable material and a laser-markable material
Classifications
U.S. Classification430/139
International ClassificationG03C8/48, G03C1/06, G03C5/08, G03C1/815, G03C1/81
Cooperative ClassificationG03C1/815, Y10S430/134, G03C1/8155, G03C1/81
European ClassificationG03C1/815C, G03C1/81, G03C1/815