Abstract: A laser dye-ablative recording element comprising a support having thereon a dye layer comprising a yellow dye dispersed in a polymeric binder, the dye layer having an infrared-absorbing material associated therewith, the yellow dye comprising curcumin.

Abstract: This invention relates to an imaging element for reductive laser-imaging comprising a support having thereon an imaging layer comprising:a) a reducible Co(III) ammine complex,b) a source of phthalaldehyde, andc) a reducing agent,the imaging layer having an infrared-absorbing material associated therewith in the amount of about 0.001 to about 0.5 g/m.sup.2 of element, and wherein the imaging element has a Lewis acid-containing overcoat layer thereon.

Abstract: This invention relates to an imaging element for reductive laser-imaging comprising a support having thereon an imaging layer comprising:a) a reducible Co(III) ammine complex,b) a source of phthalaldehyde, andc) a reducing agent,the imaging layer having an infrared-absorbing material associated therewith in the amount of about 0.001 to about 0.5 g/m.sup.2 of element.

Abstract: Squarylium compounds of the formula: ##STR1## (in which Q.sup.1 and Q.sup.2 are each a chromophoric group having an aromatic unsaturated system conjugated with the squarylium ring and such that in the compounds of formulae Q.sup.1 CH.sub.2 R.sup.1 and Q.sup.2 CH.sub.2 R.sup.2 the methylene hydrogens are active hydrogens, R.sup.1 and R.sup.2 are each independently a hydrogen atom or an aliphatic or cycloaliphatic group, and R.sup.3 and R.sup.4 are each independently a hydrogen atom, or an acyl, aliphatic, cycloaliphatic, aromatic or heterocyclic group, subject to the proviso that one of R.sup.3 and R.sup.4 may be an amino or substituted amino group, or one of R.sup.3 and R.sup.4 is a hydrogen atom and the other is an organosulfonyl group, or R.sup.3 and R.sup.4 together with the intervening nitrogen atom form a nitrogenous heterocyclic ring) are useful as near infra-red absorbers.

Abstract: A recording material employing an electron-donating achromatic dye and an electron-accepting compound, which further contains at least one triarylamine derivative represented by general: formula (1), (2), (3) or (4); ##STR1## wherein all the symbols are defined in the specification.

Abstract: Disclosed is a magnetic recording element comprising a support having coated on at least one major surface thereof a layer of a magnetic recording medium and a photosensitive layer which may be separate from or integral with the magnetic recording layer and which contains an infrared absorbing dye or its precursors. Information can be imparted to the photosensitive layer by imagewise exposure to actinic radiation which will either promote or inhibit generation or destruction of the infrared absorbing dye.

Abstract: A slide blank comprises a support at least part of which is essentially transparent; an imageable layer superposed on one face of the support, the imageable layer not being substantially photosensitive but comprising a color-forming composition, which, upon imagewise exposure to actinic radiation, forms a colored material, thereby forming in the imageable layer an image which can be viewed in transmission; and a protective layer superposed on the imageable layer on the opposed side thereof from the support, at least part of the protective layer being essentially transparent; the support, imageable layer and protective layer being secured together to form a slide blank having a thickness of at least about 0.8 mm, and the thickness of the protective layer being such that no part of the imageable layer containing the color-forming composition is more than about 0.2 mm from one external surface of the slide blank. This slide blank can be imaged to produce a ready-mounted slide.

Abstract: A laser beam absorbing resin composition is disclosed which includes 100 parts by weight of a thermosetting resin, a colorant capable of discoloring upon being heated at a temperature of 250.degree. C. or more, and at least 10 parts by weight of a particulate, laser beam absorbing substance which has an average particle size of 50 .mu.m or less and which is at least one member selected from cordierite and zeolite. By irradiating a shaped, hardened body of the above composition with a laser beam, the colorant is thermally decomposed, so that the color of the irradiated surface is changed and becomes discriminitive from that of non-irradiated surface.

Abstract: A process for producing an image uses an imaging medium comprising an acid-generating layer or phase comprising a mixture of a superacid precursor, a sensitizing dye and a secondary acid generator, and a color-change layer comprising an image dye. The sensitizing dye has a unprotonated form and a protonated form, the protonated form having substantially greater substantial absorption in a first wavelength range than the unprotonated form. The superacid precursor is capable of being decomposed to produce superacid by radiation in a second wavelength range, but is not, in the absence of the sensitizing dye, capable of being decomposed by radiation in the first wavelength range. The secondary acid generator is capable of acid-catalyzed thermal decomposition by unbuffered superacid to form a second acid.

Abstract: A novel imaging process is disclosed comprising preparing microcapsules having an elongation of less than 1%, adhering the microcapsules to a substrate then imagewise rupturing certain of said microcapsules upon selective application of a thermal energy input comprising a .DELTA.T of at least 115.degree. C. per 1 millisecond. The process makes use of novel microcapsules polymerized at a temperature of from 65.degree. C. to 100.degree. C. which are heat resistant yet heat fracturable upon application of a thermal pulse.

Abstract: A slide blank comprises a support; a mask layer having a substantially transparent central portion and a non-transparent peripheral portion surrounding the central portion; and an imageable layer which is not substantially photosensitive but is imageable to form an image which can be viewed in transmission. The support, mask layer and imageable layer are secured together so that the support and the imageable layer extend across essentially the entire transparent central portion of the mask layer, at least the portion of the support adjacent the central portion of the mask layer being substantially transparent. This slide blank can be imaged to produce a ready-mounted slide.

Abstract: Described is a radiation sensitive imaging film containing a heat fixable radiation sensitive element, e.g., a diacetylene, of the formula: R--C.tbd.C--C.tbd.C--R', where R and R' are, e.g., both --CH.sub.2 --O--CONH--(CH.sub.2).sub.5 CH.sub.3. After exposure to X-radiation during diagnostic or X-ray therapy, the resulting image can be permanently dry fixed by a short heating step and then stored for a long period. Processes for making the film, new binder-convertor systems, and a device incorporating the film are described as well as other imaging, diagnostic and therapeutic methods utilizing the film in high energy radiation applications in the health care field.

Abstract: An image forming element utilizing the photoreduction of a cobalt complex is disclosed. The image forming element comprises a support having thereon a layer comprising a cobalt complex compound represented by Formula 1 or Formula 2; ##STR1## wherein lig is a coordinating compound capable of forming a cobalt complex compound with a cobalt cation; R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently an aryl group, an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an aralkyl group, a heterocyclic group or a cyano group, provided that at least one of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an aralkyl group, a heterocyclic group or a cyano group, the above groups represented by R.sup.1, R.sup.2, R.sup.3 or R.sup.

Abstract: There are disclosed thermally-processable image recording materials comprising a support carrying thereon; a di- or triarylmethane thiolactone dye, an organic silver salt, a binder; and a select group of substituted purine compounds for reducing a post-processed formation of a yellowish-brown color (gilding) within such materials.

Abstract: A method for temporarily marking a surface whose distance from a light beam source can substantially vary, without requiring focusing or refocusing of the light beam, commences with the step of coating a portion of the surface with a light reactant, color-forming chemical solution. The solution is soluble in a liquid solvent that is nonreactive with the surface. The coated portion of the surface is exposed to a collimated, non-focused laser beam exhibiting an airy disk pattern having central bright spot, the exposure occurring for a period of time that enables the central bright spot to expose the coating and to manifest a color change at points of incidence. The bright spot exhibits a diameter that does not exceed a predetermined diameter within an expected distance variations between the source of the laser beam and the surface.

Abstract: An imaging element is disclosed comprising on a support a dye precursor and a color developer arranged in the same layer or in separate layers characterized in that a specific type of monomers according to one of formulas (I) or (II) and a photoinitiator is present in a layer containing said dye precursor and/or color developer. The imaging element of the invention can used as photosensitive as well as heat-sensitive imaging element for obtaining an image.

Abstract: A photosensitive element for the production of near infrared absorbing images having a photosensitive medium comprising a trialkyl orthoester, a photochemical source of a strong acid and a compound of the formula (I): ##STR1## wherein: n is 0 or 1,R.sup.1 and R.sup.2 are independently members selected from the group consisting of hydrogen and alkyl groups of up to 5 carbon atoms andAr.sub.1 and Ar.sub.2 are independently members selected from the group consisting of aryl groups bearing an electron-donating substituent in the 4-position.

Abstract: A laser beam is modulated with an image signal, a thermosensitive recording material, which is composed of a substrate and a color forming agent, a developing agent, and a light absorbing dye, which are overlaid on the substrate, is scanned with the modulated laser beam, and an image represented by the image signal is thereby recorded on the thermosensitive recording material. Before the image is recorded on the thermosensitive recording material, a density pattern constituted of a plurality of sections whose densities vary stepwise is recorded on a portion of the thermosensitive recording material with the laser beam. Densities of the respective sections of the density pattern recorded on the thermosensitive recording material are measured. From the results of measurements, a conversion table is created for use in conversion processing on the image signal such that the image may be recorded with an appropriate image density range on the thermosensitive recording material.

Abstract: A print-out layer is incorporated in a donor element that is useful in a dry color proofing process in which a colored image is transferred from the donor element to a receiver. To achieve full color reproduction, images are transferred in succession and in register, to the receiver from donor elements, respectively containing yellow, magenta, cyan and black colorants. A visible image is formed in the print-out layer as a result of imagewise exposure of the donor element to activating radiation and is utilized to facilitate visual registration in forming the multicolor image on the receiver.

Abstract: A novel class of N-substituted triarylmethane sulfonamides is provided which undergo reversible oxidation into colored form and reversible reduction of the oxidized form into colorless form. Preferred embodiments comprise xanthene sulfonamides having N-aryl substituents, e.g., hydroquinone substituents. These compounds possess redox potentials ranging between about +200 to -500 millivolts and thus are useful as dyes for producing photographic, photothermographic, thermal, and pressure-induced images, as well as being useful as redox indicators in a wide variety of biological and chemical reactions.

Abstract: Phothermographic material capable of producing a high density cyan image upon image-wise exposure and thermal development at a relatively low temperature and for a short period of time. The photothermographic material of the invention comprise coated on a support base at least one light-sensitive emulsion layer containing: (a) a binder; (b) a silver source material; (c) a light sensitive silver halide in catalytic proximity to said silver source material, wherein said emulsion layer or an adjacent layer thereto comprises a chromogenic cyan leuco dye.The photothermographic material of the invention may be used to obtain good cyan image of suitable density in single color or multicolor photothermographic articles. At the same time the chromogenic leuco dye is stable enough not to be oxidized by oxygen of the air or by simple heating and to limit the fog formation after development.

Abstract: A phototranschromic ink suitable for use in a printing machine, including a water soluble, inert, nonionic polymeric resin carrier base having film forming properties, a photo acid or photo base progenitor which releases or takes up protons upon exposure to light, a pH sensitive dye which changes color in response to a change in proton levels, a water compatible non-ionic wetting agent, a water compatible non-ionic thickening agent, a neutral water soluble flow aid; wherein said ink changes color upon exposure to ultraviolet radiation and is of suitable consistency for use in a printing machine.

Abstract: A novel photochromic compound as a photoreactive material making use of photochromism is provided, which compound is expressed by the following formula (1) or (2)): ##STR1## wherein R is alkyl, alkoxy, perfluoroalkyl or cyano; X.sub.1, X.sub.2, X.sub.3, X.sub.4, X.sub.5 and X.sub.6 are each H, halogen, alkyl, alkoxy, cyano, alkanoyloxy or alkyloxycarbonyl, or a substituted or unsubstituted benzene ring is formed by condensation between at adjacent groups among X.sub.1 to X.sub.6 ; Y is Y.sub.1 C=CY.sub.2, O, S, SO, SO.sub.2 or NY.sub.3 wherein Y.sub.1 and Y.sub.2 are each as defined in the case of the above X.sub.1 to X.sub.6 and Y.sub.3 is H, alkyl, alkanoyl, alkyloxycarbonyl or aryl; and the symbol refers to occurrence of E- or Z-isomer, and which compound is useful as rewritable optical memory element or photo-display element and also as solar energy-storage material, duplicating material, masking material, optical filter, toys, etc.

Abstract: A three-dimensional image is produced using an imaging medium having a lenticular screen, the lenticles of the screen dividing the opposed surface of the imaging medium into a plurality of elongate image areas, the imaging medium having on the opposed side thereof a radiation-sensitive layer, the radiation-sensitive layer comprising a color-forming composition adapted to undergo a change of color upon increase in the temperature of the radiation-sensitive layer above a color-forming temperature for a color-forming time.

Abstract: A novel light-sensitive heat-sensitive composition is disclosed, comprising a photohardenable composition, a dye which discolors upon reacting with a base, and a base precursor. A novel light-sensitive heat-sensitive recording material is also disclosed, comprising a support having provided thereon the above described light-sensitive heat-sensitive composition. In a preferred embodiment, the dye is a spectral sensitizing dye for the photohardenable composition. Furthermore, a novel image formation process is disclosed, comprising the steps of: (a) imagewise exposing the light-sensitive heat-sensitive recording material to light to cure the exposed portions of the recording material; and (b) uniformly heating the imagewise exposed recording material to discolor the dye in the unexposed portions thereof.

Abstract: A light-sensitive image-forming material is disclosed, comprising a support having thereon a recording layer containing a leuco dye which forms color upon oxidative development, a photo-oxidizing agent and a reducing agent, wherein the leuco dye is an xanthene compound having a cyclic amino group at the 2-position. The light-sensitive image-forming material of the present invention provides an image having satisfactory color density and stability to light after imagewise exposure and fixation.

Abstract: Structures for items such as promotional materials, game pieces, lottery tickets, security documents and other articles, which feature one or more thermal reactive layers that are activated by heat from a hidden image formed of infrared sensitive, heat generating material such as carbon black preprinted under the thermal reactive layers during manufacture. The thermal reactive layers permit transmission of radiant energy such as infrared to the heat generating, hidden layers. The heated image conducts heat to the thermal reactive layers which employ a coloring agent and a developer which, when exposed to the heat, react or act in concert in order to form a corresponding image on the face of the item.

Abstract: Integrated optical devices are provided wherein a film of polystyrene doped with methyl red (PS-MR) on a glass substrate, is masked, e.g. with one or more metallic strips on a glass plate and such film is irradiated with, e.g. a UV lamp, tuned within the absorption band of such film, in air, to photobleach the film portions around channels covered by the masking strips and reduce the refractive index thereof below that of the unbleached film channels. The bleached film portions then provide reflective beam confining interfaces which define the unbleached channels and form waveguides within the film. The invention takes advantage of photobleaching to change the index of refraction of portions of a thin film to define optical components therein and has located a class of films, including PS-MR, which, upon photobleaching, provide a considerable reduction in refractive index, enabling the definition of optical components in such film.

Abstract: When information recording is conducted by converting a non-colored state of a recording film into a colored state, use is made of a recording light having a wavelength in such a range that an absorbance of the non-colored state is higher than an absorbance of the colored state. When information erasing is conducted by converting a non-colored state of a recording film into a colored state, use is made of an erasing light having a wavelength in such a range that an absorbance of the non-colored state of the recording film is higher than an absorbance of the colored state. Accordingly, the present invention has the advantage of a great change of color being exhibited in the recording film, thus enabling optimal recording and erasing of information.

Abstract: Method for fabricating components for integrated optics are provided wherein a film of polystyrene doped with methyl red (PS-MR) on a glass substrate, is masked, e.g. with one or more metallic strips on a glass plate and such film is irradiated with, e.g. a UV lamp, tuned within the absorption band of such film, in air, to photobleach the film portions around channels covered by the masking strips and reduce the refractive index thereof below that of the unbleached film channels. The bleached film portions then provide reflective beam confining interfaces which define the unbleached channels and form waveguides within the film. The invention also provides for interfering two laser beams of like .lambda., at a coupling spot on the film, which beams are again tuned within the absorption band of such film, which bleach alternate lines or bars of such film to provide a phase grating therein.

Abstract: A method for forming an image is described which includes bringing a transparent heat-sensitive recording material including a transparent support made of a synthetic polymer having thereon a transparent heat-sensitive recording layer into contact with a light-absorbing material, at least at the time of effecting recording, and irradiating the light-absorbing material with a laser beam to heat the transparent heat-sensitive recording layer and to cause color formation therein. High speed, high density, and high quality recording can be performed with an increased light absorption efficiency.

Abstract: This invention relates to novel recording materials which employ color-forming di- and triarylmethane compounds possessing certain S-containing ring-closing moieties, namely, or thiolactone, dithiolactone or thioether ring-closing moiety and to a method of forming color by contacting these dye precursor compounds with a Lewis acid material capable of opening the thiolactone, dithiolactone or thioether ring-closing moiety whereby the compound is rendered colored, that is, converted to its chromophore color.

Abstract: A thermal imaging method for forming color images is provided which employs as the color image-forming material, a colorless precursor of a preformed image dye possessing at least one thermal protecting group that undergoes fragmentation upon heating and at least one leaving group that undergoes irreversible elimination upon heating, said protecting and leaving groups maintaining the precursor in its colorless form until heat is applied to effect removal of these groups whereby the precursor is converted to an image dye.

Abstract: A light-sensitive recording medium using a photochromic material produced at a low cost, without necessity of fixing free rotation of bonds in its cis compound and removing its trans compound, is disclosed, the recording medium comprising a substrate having thereon a recording layer which contains a photochromic material capable of cis-trans isomerization upon irradiation with light, wherein not more than 50 mol % of the photochromic material has a trans configuration when the recording layer is in a color-disappearing state.

Abstract: An optical memory device comprising:a transparent substrate; anda recording film deposited on the transparent substrate, the recording film being formed by preparing a composition in which a diarylethene-type photochromic compound is dispersed in an ultraviolet-curing polyurethaneacrylate resin of solventless type and by curing the composition by an ultraviolet ray irradiation.

Abstract: A multicolor recording material is disclosed, which comprises a support having provided thereon at least two layers each containing a leuco dye which is capable of forming a color by oxidation and a photo-oxidizing agent, wherein the leuco dyes contained in each layer are capable of forming different color from each other and the photo-oxidizing agents contained in each layer respond to light having different wavelength from each other.

Abstract: A master disc which is provided on one side with a reflective optical structure and a recording double-layer is exposed to a first laser beam which scans the optical structure and to a second laser beam which is controlled by the first beam, information bits in the form of bulges being formed in the recording layer due to exposure to the second beam, a metal skin being subsequently provided on the recording layer, in which metal skin the surface structure of the recording layer is copied and, finally, the matrix thus obtained being removed from the master disc.

Abstract: An optical image-recording material comprising:(a) microcapsules, in which at least one leuco dye capable of forming a color by oxidation and at least one photo-oxidizing agent are enclosed together, and (b) at least one reducing agent not enclosed in the microcapsules, or(c) microcapsules, in which at least one reducing agent is enclosed, and (d) both at least one leuco dye capable of forming a color by oxidation and at least one photo-oxidizing agent not enclosed in the microcapsules,wherein the microcapsules have capsule walls made from a material which lowers its permeability barrier to at least one component selected from the photo-oxidizing agent and the reducing agent when the capsule wall material is heated above its glass transition temperature, and the leuco dye is a xanthene compound having an N-substituted anilino group substituted by an electron attracting group.

Abstract: An ion permeable membrane, comprising two or more groups of substances having different sensitive wavelength regions in a lipid membrane, is provided.

Abstract: The invention relates to an optical data recording method which comprises addressing a recording device using an infra-red laser modulated with a waveform of the information to be recorded, wherein said recording device comprises an infra-red absorbing material and a photochromic fulgide which is converted into its colored form under the influence of the heat absorbed from the laser, and updating the recording by erasing undesired previously recorded data using a laser operation in the visible region of the spectrum.

Abstract: A fiber-reinforced composite vehicle wheel that comprises an annular rim for receiving a vehicle tire and a central disc internally spanning the rim for mounting the rim and tire on a vehicle. Mounting openings are formed in the wheel disc in an array that surrounds the wheel axis of rotation, and are received in assembly with a vehicle over mounting studs that project from a mounting plate. Mounting nuts are threaded onto the studs and seated against opposing axially-oriented conical surfaces of the wheel disc surrounding each mounting opening for clamping the wheel firmly against the mounting plate. A layer of antiseize lubricant is located on the disc seating surfaces surrounding the mounting openings prior to assembly of the fastener nuts.

Abstract: Color images with improved Dmin/Dmax-relationship can be obtained from color photographic recording materials comprising color providing compounds in association to silver halide emulsion layers and comprising an additional binder in said silver halide emulsion layers or in adjacent non-lightsensitive layers a polymer having recurring structural units of a polymerized monomer which contains at least one urethane and/or urea group.

Abstract: A photographic contact printing process is disclosed having application in the mass production of replicate video discs from a master disc, and other applications wherein it is desired to replicate micro-detail over a relatively large area. A problem with conventional contact printing from a mask to a photographic medium is one of maintaining intimate contact over a relatively large area since dust, dirt, etc., are almost impossible to completely eliminate in any practical manner. In accordance with the present invention, a contact printing process is provided wherein intimate contact is not necessary for making high quality contact prints. The present invention recognizes that in contact printing information from a master disc to a replicate disc, the contact printing process is significantly less sensitive to imperfect contact between the master disc and the replicate disc if one employs a replicate disc comprising a photosensitive material having a certain optical properties.

Abstract: A compound represented by the following general formula [I] ##STR1## wherein ##STR2## represents a norbornylidene group or an adamantylidene group each of which may have a substituent, andX represents an oxygen atom, the group >N--R.sub.2, the group >N--A.sub.1 --B.sub.1 --A.sub.2).sub.m (B.sub.2).sub.n R.sub.3, the group >N--A.sub.3 --A.sub.4, or the group >N--A.sub.3 --A.sub.4, provided that when ##STR3## is an adamantylidene group, X is selected from the above groups excepting the oxygen atom and the group >N--R.sub.2 ; and plastic lens containing the compound of the above formula [I].

Abstract: This invention relates to the use of 3,5-dihydroxybenzoic acid as an organic acidic reagent in thermographic recording materials comprising a di- or triarylmethane thiolactone dye precursor, silver behenate and a polymeric binder, and in a further embodiment, relates to coating compositions useful in the preparation of the recording materials.

Abstract: The invention relates to a process for producing supports intended for the optical recording and reading of information. A layer containing a diazo compound is deposited onto a metallized substrate. Recording is obtained by exposing the support to light through a mask, the exposed zones of the layer of diazo compound being decomposed. Dry development in ammonia vapors shows up transparent zones and opaque zones corresponding to the information.

Abstract: Photopolymerizable recording materials suitable for producing photoresist layers and lithographic printing plates are composed of one or more photopolymerizable olefinically unsaturated organic compounds, optionally a polymeric binder, one or more photopolymerization initiators, a color-forming system which on irradiation with actinic light causes an increase in the color intensity of the recording material, a sensitizer and optionally further additive and/or auxiliary substances, and contain as the color-forming system(a) one or more colorless or virtually colorless organic compounds which are oxidizable to colored compounds, and(b) a photooxidant for the colorless or virtually colorless organic compound(s) (a),wherein photooxidant (b) comprises an organic salt with a substituted or unsubstituted hetaromatic system, this hetaromatic system having one or more built-in groups of the general formula (I) ##STR1## where R is substituted or unsubstituted alkenyl, alkynyl, hetaryl, alkoxycarbonyl, carbamoyl, alkyls

Abstract: A photochromic system contains an oxidizable leuco dye and a photochemically activated initiator which converts the leuco dye to the dye, the initiator being a phenanthroimidazole derivative.The photochromic system is useful for the production of photochromic layers for photoresists and printing plates.

Abstract: Coated abrasive binders made from a photocurable addition-polymerizable composition containing a free-radically-polymerizable monomer and a photoinitiator system containing (i) an arylidonium salt, (ii) a sensitizing compound, and (iii) an electron donor having an oxidation potential that is greater than zero and less than or equal to that of p-dimethyoxybenzene (1.32 volts vs. S.C.E.). The binders cure rapidly and deeply under ultraviolet or visible light, even when filled with large amounts of mineral grain or with coarse grades of minerals.

Abstract: A contrast mask for a transparent photographic original may be formed by illuminating a photochromic body (11,41) through the original with white light. Preferably the photochromic body (11,41) is optically neutral (grey) and contains a silver halide as a photochromically active substance. Preferably the mask-forming exposure is performed separately from the photographic exposure of a recording medium through the original and the mask, by a different light source (27). The optical contrast range of the mask can be varied in response to the optical contrast range of the original by varying the amount of the mask-forming exposure. This variation is preferably effected by varying the number of flashes of the light source (27).The photochromic body is preferably incorporated in the holder (1,33) for the transparent original.Photographic reproduction apparatus may include an automatic densitometer, the output of which controls the amount of the mask-forming exposure.