US3341330A - Method of forming thermally stable photochromic images and product - Google Patents

Method of forming thermally stable photochromic images and product Download PDF

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Publication number
US3341330A
US3341330A US338136A US33813664A US3341330A US 3341330 A US3341330 A US 3341330A US 338136 A US338136 A US 338136A US 33813664 A US33813664 A US 33813664A US 3341330 A US3341330 A US 3341330A
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US
United States
Prior art keywords
layer
image
photochromic
ultraviolet light
images
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US338136A
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English (en)
Inventor
Peter L Foris
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Appvion LLC
NCR Voyix Corp
National Cash Register Co
Original Assignee
NCR Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NCR Corp filed Critical NCR Corp
Priority to US338136A priority Critical patent/US3341330A/en
Priority to GB51792/64A priority patent/GB1030217A/en
Priority to SE15634/64A priority patent/SE305809B/xx
Priority to DEN26062A priority patent/DE1282452B/de
Priority to FR1683A priority patent/FR1420307A/fr
Priority to DK16665AA priority patent/DK116636B/da
Priority to BE658273A priority patent/BE658273A/xx
Priority to AT24265A priority patent/AT257355B/de
Priority to CH63065A priority patent/CH431268A/fr
Priority to NL6500513A priority patent/NL6500513A/xx
Application granted granted Critical
Publication of US3341330A publication Critical patent/US3341330A/en
Assigned to APPLETON PAPERS INC. reassignment APPLETON PAPERS INC. MERGER (SEE DOCUMENT FOR DETAILS). FILED 12/1781, EFFECTIVE DATE: 01/02/82 STATE OF INCORP. DE Assignors: GERMAINE MONTEIL COSMETIQUES CORPORATION (CHANGED TO APPLETON PAPERS), TUVACHE, INC.
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/685—Compositions containing spiro-condensed pyran compounds or derivatives thereof, as photosensitive substances
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
    • Y10S430/163—Radiation-chromic compound

Definitions

  • the images in contemplation are created in or on a layer of material having sensitivity to ultraviolet light, the sensitivity of such layer being contributed by the presence of molecules of at least one photochromic compound.
  • Photochromic compounds are those that undergo, what is believed to be, an internal molecular rearrangement, from a normal condition, when subjected to ultraviolet radiation, and in which rearranged-condition each molecule radiation, and in which rearrangedcondition each molecule has a light-absorption characteristic different than it had in the normal condition.
  • the molecules in the layer are affected by radiation individually, and each molecule acts in an independent way to contribute to the overall visual concert-effect in a given area that is provided with a sufficient profusion of such molecules.
  • the ultra-violet-light-rearranged-condition of the photochromic material will, for the purposes of this disclosure, be termed the colored state and the normal condition will, in some instances, be termed the colorless state, because most of the compounds evidence to the normal human eye, while in the colored state, in daylight or artificial light, a distinctive color within the visible spectrum and, on the other hand, in the colorless state evidence a colorless, a white, or a light-colored hue.
  • some molecules may be in one state or another dependent on the light and heat energy to which they may have been subjected, that is to say-the colored state or the colorless state, but all of the molecules, if the colored state, will in the absence of ultraviolet light revert to the colorless or equilibrium state in time, at a rate which increases with the ambient temperature.
  • the reversion to the colorless state therefore, causes a gradual fading of a colored image with time.
  • the colored state is assumed substantially instantaneously if a powerful source of ultraviolet light is applied to the photochromic compounds while the molecules are not bound in crystalline arrangement.
  • This instantaneous change of course itself is effected molecule-by-molecule but in a short enough time that the rate of change is not apprehended by the human mind.
  • the compounds differ among themselves as to the rate of reversion at a given temperature, the reversion to normal of the colored state of the molecules of some compounds being so fast at room temperature as to render them of no utility as a persistent color-contributor, whereas the molecules of other compounds remain in the colored state for hours, days, months, or years, depending on their molecular structure, in spite of the ever-present urging of them to the normal colorless state by ambient heat.
  • the fixing of a photochromic layer halts the thermal reversion tendencies of the colored state of an image therein to the colorless state by the formation of a chemical complex of some kind, the exact nature of which is not fully understood but which, if the compound is a benzo-indolinospiro pyran, imparts a yellow color to the layer, such color being pale in any portion not subjected to ultraviolet light and of a deep yellow color where struck by ultraviolet light to form the image.
  • this complex while forming with the molecules in uncolored state does not render the uncolored molecules fixed against being changed to the deep yellow colored complexed state by subsequent ultraviolet light. Therefore, to make permanent records, the photochrornic layer may be treated with acid vapors before or after being subjected to ultraviolet light.
  • a photochromic layer if treated withthe acid vapor before or after image formation, may be reversed to the uncomplexed state with alkaline vapors.
  • the invention provides far superior recording systems to that possible with any photochromic layers heretofore known.
  • the photochromic art before this invention provided a rather evanescent recording medium, not having the permanence required for durable records.
  • the photochromic layer of this invention may be an amorphous solid layer of the molecules laid down on a plate, sheet, or other support web, by evaporation of a concentrated liquid solution of the photochromic compound, preferably applied thinly thereto, or it may be a solid solution film of photochromic molecules in a polymeric film-former material. It is within the scope of the invention to lay down on the same support Web two or more different layers of material, distinguished or not by their photochromic compound content or differing by acting together.
  • the vapors used for 'the state of the photochromic material be it amorphous in solid state or in solution. It is also within the concept of the invention to have different areas of the same record material support sheet sensitized with different photochromic compounds to give a distinctive color to the areas according to the compound used, thus one area may have data recorded in one distinctive color associated with the photochromic molecules employed therein, which is in contrast to that of an adjoining area which employs other types of photochromic molecules. Or the different areas maybe distinguished by a diiference in the thermal persistence characteristics of different photochromic compounds used.
  • the recording of data may be made onto the novel record material by a beam or a cone of ultraviolet light of proper intensity and wave length, selectively applied directionally or by controlled intensity to the sheet.
  • light-control means such as shutters and stencils may be used togive selective operation of recording light, or other manner of light control may be used-such as filters, variations of period of the lightapplication, or the use of two or more
  • the fixing of a photochromic layer with an acid vapor can be carried out by placing the record material, in part gas-confining compartment, such as a chemicalhood, and the same apparatus may be used the reversion of the layer or images as will be described.
  • the layer also may be selectively fixed or reverted by applying the vapors locally to an area desired to be modified to the exclusion of the remainder of the layer, in any pattern or mode desired, such selection choice extending to a sheet of support material coated with a layer on either side whereof one side is treated differentially to the other to obtain a combination of'images visually observable in thickness.
  • the objects of the invention may be stated as being to provide means for making thermally-stabilized photochromic layers, or images in such layers, in the form of chemical complexes; to provide means for reversing such fixed layers or images to their former uncomplexed state; and in general to provide a means for making permanent records with photochromic materials that because of temperature conditions could not before be used.
  • the molecules of these compounds must have molecular freedom to change configuration, and in such free state are easily converted to the colored form by ultraviolet light while in solution, be it a liquid solution or a solid solution, or in an amorphous solid state adherent to a support surface or included within a polymeric film support. In crystalline form these compounds are difficultly converted to the colored" state and difficultly revert to the colorless state so as to render them useless for record-making on a commercial scale.
  • FIG. 1 shows a support 20 with the layer 21 comprising the photochromic compound made either in an amorphous thin layer form or in a solution state (solid-solution form or liquid-solution form) or made as a thin solid film of polymer material with the photochromic material in substantially .an amorphous form distributed therein. From a convenience point of view, and to prevent rapid sublimation of the material, a solution of the photochromic material in a thin polymer film solutionformer is to be preferred;
  • FIG. 2 shows the application of ultraviolet light to the layer 21 under the control of an aperture-type of stencil which is to be taken as typical of light-image control means, the image of the letter N in dark blue colored form being represented in solid black on layer 21;
  • FIG. 3 shows the plate 20 bearing the image 21 being subjected to the acid-vapors of HCl within an enclosure, whereby the image N is fixed as a dark yellow complex with a pale yellow background shaded horizontally;
  • FIG. 4 shows the layer with the fixed photochromic image during its treatment with ammonia vapor to reverse it to unfixed condition
  • FIGS. 5, 6 and 7 refer to an alternative method, especially useful for photochromic compounds not ordinarily operable at room temperature, wherein as shown in FIG. 5, the prepared photochromic layer is treated first with acid vapor, before any image is impressed thereon, to fix the whole layer to a pale yellow complex of the colorless form of the photochromic material, to prepare it for the reception of images by ultraviolet light;
  • FIG. 6 shows the fixed colored 5 after being subjected to ultraviolet light; and
  • FIG. 1 shows the photochromic colore image reversed by havrecord condition of FIG.
  • photochromic layer image according to the teachings of the invention using non-halogen acid vapors.
  • the data to be recorded may be in terms of the colored portion of the layer or, on the other hand, in terms of the colorless portion of the layer, the image being that portion affected by ultraviolet light.
  • the deep yellow of the image is retained and it may be visually enhanced by flooding all of the layer with ultraviolet light, to color the background to give an enhanced visibility to the deep yellow of the image by color-contrast.
  • amorphous layer of photochromic material by deposition from a liquid solution, the material is dissolved in a readily evaporable liquid applied in a thin film to a clean substrate surface, such as the surface of a sheet of glass. Purity of these compounds tends towards unwanted crystallization of such layers, if compounds are used singly. A mixture of closely related photochromic compounds will prevent the crystallizing tendency through steric hindrance, An impure photochromic compound is more apt to yield an amorphous film than a pure one.
  • Images, then, formed by the ultraviolet light in amorphous layers of photochromic material tend to fade and disappear in time through thermal decay phenomena through heat energy obtained from the environment.
  • the invention is directed to means for fixing such images against such fading and disappearance, and to provide means for re-establishing the material by a reversing step so as to be responsive to further recording, or to be more available for an optimal step of coloring the background to improve observation.
  • a SOLID Amorphous layer on er support sheet Glass is a most suitable substrate for preparing films or layers according to the invention, being smooth, rigid, transparent in its ordinary form, and highly resistant to the materials employed.
  • any equivalent support of metal, fiber, mineral, ceramic, polymer, and the like, may be used, as desired.
  • These films are dark blue in the colored substantially without hue in the colorless subject to direct contact reaction with alkaline vapors.
  • an initial layer of the 5Cl-6NO derivative of the parent benzo-indolinopyrospiran may be laid down on a plate, an image created thereon by ultraviolet light, and a complex formed with HCl vapor, after which the background pale yellow complex is: removed with toluene, leaving the toluene-resistant image in dark yellow.
  • a second amorphous layer of the 6NO -8OCH derivative from benzene solution, and a selected image is created with ultraviolet light over the first image.
  • the treatment of the plate again with HCl vapor results in the two superimposed, but not necessarily alined images in deep yellow. Treatment of the whole plate with ammonia vapor yields a purple image on the bottom and a blue image over-laying it, as the colored states of the two images are of dififerent hue.
  • Example I the preferred one, a sheet is prepared according to preparation instructions (A) and subjected to a cone of ultraviolet radiation, from a source producing radiation strong at 3000 A., through a stencil as in FIG. 2 to produce the letter N in dark blue on a colorless background.
  • the ultraviolet-light-exposed sheet then is placed under a hood with HCl vapor, at atmospheric-pressure and room-temperature, for a few seconds, by which time the layer has turned yellow with the image N appearing as a darker yellow hue.
  • the paler yellow portions of the layer will, within a few minutes, resume the colorless state due to sublimation of the vapor, leaving the N image in thermally-stabilized form of deep yellow hue.
  • the background will still be sensitive to ultraviolet light.
  • Example H The steps of Example I are followed with the further step of flooding the finished plate with ultraviolet light to produce a blue-colored background for the deep yellow N.
  • Example IlI.-A sheet prepared according to the instructions (B) is first subjected to HBr vapor for a few seconds at atmospheric pressure and room temperature to turn the film to the pale yellow complex. Next, the complexed layer is subjected to a selectively directed beam of ultraviolet light to trace an image which appears in dark yellow against a pale yellow background.
  • Example I V.Example III is followed with the added steps of:
  • Example V Any of the foregoing Examples I to IV is reversed to normal as to part of its area only by subjecting only such part of it to NH, vapor, the other parts being physically masked.
  • Example VI Photochromic layers are laid down on either face of a sheet made of material opaque to ultraviolet light but which is transparent to visible light of the longer wave lengths. Images are made with ultraviolet light on each layer of different subject matter and one or both sides are fixed by halogen acid vapors. Then at will, whatever area is to appear in normal colored state is treated with the reversing alkaline vapor. The sheet is viewed from one side or the other by incident light or through the sheet by transmitted light to obtain a composite effect.
  • Example Vll In this example a plate is prepared according to instructions (A), an image is formed thereon by projecting ultraviolet light to it in the desired pattern. The plate then is treated with S vapor which combines with the colored image to form a stable yellow complex but which leaves the background unconverted in the original colorless form, as S0 though an acid vapor is not an acid of the halogen group. This background is still sensitive to ultraviolet light for more recording and fixing.
  • the stable SO -yellow images may be reversed with alkaline vapors as was the case with the other examples.
  • a recording made on the colorless state of the layer may be fixed only after the recording, whereas if the fixing" is with a halogen type of acid vapor it may be carried out before the application of ultraviolet light.
  • steps of the invention may be of combinations using the fixing and reversing steps when needed, and that combinations of photochromic compounds and means for forming images to complement or supplement one another, are provided.
  • the invention is characterized also by the distinguishing use of halogen acid vapors and non-halogen acid vapors, as the occasion of use demands.
  • thermoly-stable images made on plates sensitized with a photochromic spiropyran material including the steps of forming the desired image on the plates by application thereto of ultraviolet light in selected image representing areas; and thereafter subjecting the plate having the so-formed image to hydrohalic acid vapors.
  • thermoly-stable images made on plates sensitized with photochromic spiro-py-ran material including the steps of forming the desired image on the plates with ultraviolet light after having subjected the sensitized plates to hydrohalic acid vapors.
  • thermally-stable photochromic images including the steps of:
  • a method of recording consisting of the steps of:
  • a method of recording consisting of the steps of:
  • a method of recording consisting of the steps of:
  • a method of recording including the steps of preparing a photochemically-sensitive film comprising compounds of benzo-indolinospiropyran structure; forming an image thereon by applying ultraviolet light in selected patterns; and flooding the film with an acid vapor selected from the group consisting of hydrohalic acid vapors and sulfur dioxide vapors until a yellow complex forms involving the acid and the photochromic molecules.
  • a method of recording data including the steps of forming an image in a layer sensitized with photochromic material by means of first forming a complex of the photochromic material of the layer with hydrohalic acid vapors; and forming the image of the data in terms of an acid complex of the photochromic material of the layer with ultraviolet light.
  • a method of recording consisting of the steps of:
  • the method of forming thermally-stable images by ultraviolet light including the steps of:
  • the method of forming thermally-stable images by use of ultraviolet light including the steps of:

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
US338136A 1964-01-16 1964-01-16 Method of forming thermally stable photochromic images and product Expired - Lifetime US3341330A (en)

Priority Applications (10)

Application Number Priority Date Filing Date Title
US338136A US3341330A (en) 1964-01-16 1964-01-16 Method of forming thermally stable photochromic images and product
GB51792/64A GB1030217A (en) 1964-01-16 1964-12-21 A process for thermally stabilizing images produced in layers of photochromic material by ultra-violet irradiation
SE15634/64A SE305809B (da) 1964-01-16 1964-12-23
DEN26062A DE1282452B (de) 1964-01-16 1965-01-12 Verfahren zum Stabilisieren von Bildern in Schichten aus photochromen Stoffen
DK16665AA DK116636B (da) 1964-01-16 1965-01-13 Fremgangsmåde til reversibel stabilisering af billeder frembragt i et lag af en eller flere ukrystallinske fotochrome spiropyranforbindelser ved ultraviolet bestråling.
FR1683A FR1420307A (fr) 1964-01-16 1965-01-13 Procédé pour la stabilisation réversible d'images produites dans une couche photochromique par application de radiations ultra-violettes
BE658273A BE658273A (da) 1964-01-16 1965-01-14
AT24265A AT257355B (de) 1964-01-16 1965-01-14 Verfahren zum reversiblen Fixieren von in Schichten aus photochromem Stoff durch Bestrahlung mit ultravioletten Licht erzeugten Bildern
CH63065A CH431268A (fr) 1964-01-16 1965-01-15 Procédé pour la formation d'images stables dans une couche photochromique par application de radiations ultra-violettes
NL6500513A NL6500513A (da) 1964-01-16 1965-01-15

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Application Number Priority Date Filing Date Title
US338136A US3341330A (en) 1964-01-16 1964-01-16 Method of forming thermally stable photochromic images and product

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US (1) US3341330A (da)
AT (1) AT257355B (da)
BE (1) BE658273A (da)
CH (1) CH431268A (da)
DE (1) DE1282452B (da)
DK (1) DK116636B (da)
FR (1) FR1420307A (da)
GB (1) GB1030217A (da)
NL (1) NL6500513A (da)
SE (1) SE305809B (da)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3471290A (en) * 1965-10-01 1969-10-07 Xerox Corp Photochromic photoresist imaging
US3532540A (en) * 1967-10-26 1970-10-06 Ncr Co Differential adhesion process for making high resolution thin film patterns
US3627690A (en) * 1969-10-01 1971-12-14 Itek Corp Photochromic naphthopyran compositions
US4171980A (en) * 1975-04-24 1979-10-23 La Cellophane Photosensitive compositions and recording materials and processes utilizing same
US4172725A (en) * 1975-04-24 1979-10-30 La Cellophane Photosensitive compositions and recording materials and processes utilizing same
US5501945A (en) * 1994-08-30 1996-03-26 The University Of Akron Method of using multichromic polymers in packaging
US20030168580A1 (en) * 2002-03-07 2003-09-11 Cis Institut Fur Mikrosensorik Gmbh Sensor detecting reflected light and method for its manufacture
US6696229B1 (en) 1999-07-08 2004-02-24 Kromotek, Ltd. Dry photographic printing process
US20150131291A1 (en) * 2012-05-31 2015-05-14 Nokia Corporation Apparatus and method for use in different ambient lighting conditions

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3140948A (en) * 1961-10-18 1964-07-14 Horizons Inc Photography
US3184308A (en) * 1962-05-23 1965-05-18 Meyer S Agruss Process for treating leucocyanide dye images and product thereof
US3212898A (en) * 1962-11-21 1965-10-19 American Cyanamid Co Photosensitive compositions of matter comprising photochromic materials suspended in polyester binders

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3140948A (en) * 1961-10-18 1964-07-14 Horizons Inc Photography
US3184308A (en) * 1962-05-23 1965-05-18 Meyer S Agruss Process for treating leucocyanide dye images and product thereof
US3212898A (en) * 1962-11-21 1965-10-19 American Cyanamid Co Photosensitive compositions of matter comprising photochromic materials suspended in polyester binders

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3471290A (en) * 1965-10-01 1969-10-07 Xerox Corp Photochromic photoresist imaging
US3532540A (en) * 1967-10-26 1970-10-06 Ncr Co Differential adhesion process for making high resolution thin film patterns
US3627690A (en) * 1969-10-01 1971-12-14 Itek Corp Photochromic naphthopyran compositions
US4171980A (en) * 1975-04-24 1979-10-23 La Cellophane Photosensitive compositions and recording materials and processes utilizing same
US4172725A (en) * 1975-04-24 1979-10-30 La Cellophane Photosensitive compositions and recording materials and processes utilizing same
US5501945A (en) * 1994-08-30 1996-03-26 The University Of Akron Method of using multichromic polymers in packaging
US6696229B1 (en) 1999-07-08 2004-02-24 Kromotek, Ltd. Dry photographic printing process
US20030168580A1 (en) * 2002-03-07 2003-09-11 Cis Institut Fur Mikrosensorik Gmbh Sensor detecting reflected light and method for its manufacture
US7030359B2 (en) * 2002-03-07 2006-04-18 CiS Institut für Mikrosensorik gGmbH Sensor detecting reflected light and method for its manufacture
US20150131291A1 (en) * 2012-05-31 2015-05-14 Nokia Corporation Apparatus and method for use in different ambient lighting conditions
US9638395B2 (en) * 2012-05-31 2017-05-02 Nokia Technologies Oy Apparatus and method for use in different ambient lighting conditions

Also Published As

Publication number Publication date
GB1030217A (en) 1966-05-18
CH431268A (fr) 1967-02-28
DE1282452B (de) 1968-11-07
SE305809B (da) 1968-11-04
DK116636B (da) 1970-01-26
BE658273A (da) 1965-04-30
NL6500513A (da) 1965-07-19
FR1420307A (fr) 1965-12-03
AT257355B (de) 1967-10-10

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