US3441947A - Thermoplastic recording process - Google Patents

Thermoplastic recording process Download PDF

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Publication number
US3441947A
US3441947A US3441947DA US3441947A US 3441947 A US3441947 A US 3441947A US 3441947D A US3441947D A US 3441947DA US 3441947 A US3441947 A US 3441947A
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Prior art keywords
layer
vinyl
poly
photoconductive
copolymer
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Ulrich Schmiedel
Louis Achille Meeussen
Paul Maria Cassiers
Rene Maurice Hart
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Gevaert Photo Producten NV
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Gevaert Photo Producten NV
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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/76—Television signal recording
    • H04N5/80—Television signal recording using electrostatic recording
    • H04N5/82—Television signal recording using electrostatic recording using deformable thermoplastic recording medium
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G13/00—Electrographic processes using a charge pattern
    • G03G13/04—Exposing, i.e. imagewise exposure by optically projecting the original image on a photoconductive recording material
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G16/00—Electrographic processes using deformation of thermoplastic layers; Apparatus therefor
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02—Charge-receiving layers
    • G03G5/022—Layers for surface-deformation imaging, e.g. frost imaging
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
    • G03G5/07—Polymeric photoconductive materials
    • G03G5/071—Polymeric photoconductive materials obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
    • G03G5/07—Polymeric photoconductive materials
    • G03G5/071—Polymeric photoconductive materials obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • G03G5/072—Polymeric photoconductive materials obtained by reactions only involving carbon-to-carbon unsaturated bonds comprising pending monoamine groups
    • G03G5/073—Polymeric photoconductive materials obtained by reactions only involving carbon-to-carbon unsaturated bonds comprising pending monoamine groups comprising pending carbazole groups
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
    • G03G5/07—Polymeric photoconductive materials
    • G03G5/071—Polymeric photoconductive materials obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • G03G5/072—Polymeric photoconductive materials obtained by reactions only involving carbon-to-carbon unsaturated bonds comprising pending monoamine groups
    • G03G5/0732—Polymeric photoconductive materials obtained by reactions only involving carbon-to-carbon unsaturated bonds comprising pending monoamine groups comprising pending alkenylarylamine
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B11/00—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor
    • G11B11/16—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by mechanical cutting, deforming or pressing
    • G11B11/18—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by mechanical cutting, deforming or pressing with reproducing by optical means
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B9/00—Recording or reproducing using a method not covered by one of the main groups G11B3/00 - G11B7/00; Record carriers therefor
    • G11B9/08—Recording or reproducing using a method not covered by one of the main groups G11B3/00 - G11B7/00; Record carriers therefor using electrostatic charge injection; Record carriers therefor
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11C—STATIC STORES
    • G11C13/00—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00
    • G11C13/04—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00 using optical elements ; using other beam accessed elements, e.g. electron or ion beam
    • G11C13/048—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00 using optical elements ; using other beam accessed elements, e.g. electron or ion beam using other optical storage elements

Definitions

  • This invention relates to novel methods for recording and reproducing information.
  • thermoplastic tape According to a recently proposed method (W. E. Glenn, Journal of Applied Physics, volume 30, pages 1870-1873, 1959), information is recorded in the form of deformations or ripples in the surface of a thermoplastic tape.
  • the information can be detected optically by projecting light through these ripples to form a visible image on a screen.
  • the tape consists of a high melting base film coated with a metallic conducting layer which is in turn coated with the low melting thermoplastic material.
  • an electron gun information can be written on the surface of the thermoplastic layer in the form of a charge pattern.
  • electrostatic forces between the charge pattern and the metallic, conductive layer caused deformations or ripples in the tape surface.
  • thermoplastic material freezes these deformations, thus yielding a permanent record of the recorded information.
  • a modi- -fied Schlieren optical system is employed to project the recorded information on a screen.
  • the tape may be erased for reuse by heating the film above its melting point for a period of time suificient to allow the charge pattern to drain away and to allow the surface tension of the thermoplastic layer to smooth out the deformations.
  • thermoplastic recording process will be employed to indicate the process described.
  • thermoplastic recordation of information on a photoconductive, polymeric material by effecting the thermoplastic recordation of information on a photoconductive, polymeric material.
  • the method of the present invention utilizes a low melting, thermoplastic, photoconductive, polymeric material.
  • the tape consists of a high melting base 3,441,947 Patented Apr. 29, 1969 ice film coated with a thin, conductive layer which is in turn coated with a photoconductive polymeric layer.
  • the use of a photoconductive, polymeric material enables simpler, more efficient recording apparatus than has been heretofore possible in thermoplastic recording processes.
  • a uniform electrostatic charge is placed on the surface of the photoconductive layer of the thermoplastic tape by exposure to a charging device, such as a corona generating device.
  • a charging device such as a corona generating device.
  • the charge in the exposed areas of the tape is dissipated by virtue of the selective increase in conductivity in these areas.
  • the tape then contains an image in the form of a charge pattern.
  • the tape is then further processed in the manner according to Glenn by first, heating the tape above the melting point of the photoconductive layer to allow deformations or ripples to form in the surface of the tape; second, cooling the tape to freeze these ripples into a permanent record and third, optically detecting the recorded information in a suitable projection apparatus.
  • the method of the present invention constitutes an improvement over the prior art process.
  • the method of the present invention merely involves simple charging and exposure operations which can be carried out with simple equipment under atmospheric pressure condition.
  • the present method is therefore less expensive, more efiicient and less complicated than the prior art methods.
  • Photoconductive polymeric materials useful in the process of the present invention include any macromolecular substance or any mixture of macromolecular substances which on exposure to radiation of suitable wavelength exhibits an increase in conductivity.
  • the following classes of polymeric substances have been found to be especially useful:
  • Vinyl polymers with acetal groups such as, e.g.,
  • A represents a divalent radical such as NHCO, NHCONH or 0C0;
  • R represents a hydrogen atom or a substituent of the aromatic nucleus such as methoxy group
  • R represents a hydrogen atom or a methyl group, such as, e.g.,
  • Poly (4-methacrylyloxy) -stilbene Poly p- N'-vinylureido -stilbene] Poly [4-methoxy-4'- (N-acrylyl -aminostilbene] Copolymer of vinyl acetate and p-(N-vinylureido)-stilbene,
  • Y represents an oxygen atom or a sulfur atom
  • R represents a hydrogen atom or a methyl group, such as, e.g.,
  • A represents a divalent radical such as or a single bond
  • Q and Q each represents a hydrogen atom, a methyl radical, a nitro group, a phenyl group, a substituted phenyl group, or form together the atoms necessary to close a ring;
  • R represents a hydrogen atom or a methyl group
  • A represents a single bond or CH CH OCO;
  • Q Q and Q each represents a hydrogen atom or a phenyl nucleus; and
  • R represents a hydrogen atom or a methyl group, such 4 as, e.g.,
  • Y represents a single bond, 3.
  • sulphur atom or a carbonyl Z represents a carbonyl group or a nitrogen atom substituted by a lower alkyl radical; and R represents a hydrogen atom or a methyl group, such as, e.g.,
  • Nitrated terpolymer (vinyl acetate/styrene/maleic anhydride),
  • A represents a single bond, or a divalent organic radical such as, e.g.,
  • R and R each represents a hydrogen atom or a lower alkyl radical such as, e.g., a methyl radical;
  • Z represents a sulphur atom or a single bond;
  • Z represents a rnethine group or a nitrogen atom;
  • Q and Q together represent the atoms necessary to complete an aromatic nucleus; and
  • Q and Q together represent the atoms necessary to complete an aromatic nucleus, such as, e.g.,
  • A represents an aromatic nucleus such as, e.g., a benzene nucleus or a heterocyclic nucleus such as a carbazole nucleus;
  • B represents an aromatic nucleus such as e.g., a benzene, a naphthalene or anthracene nucleus, or a heterocyclic nucleus such as, e.g., a carbazole, phenothiazine or quinoline nucleus;
  • R represents a hydrogen atom or a lower alkyl radical such as, e.g., a methyl radical
  • n and m each represents a positive integer from 1 to 2
  • Polyesters such as, e.g.,
  • Copolyester of terephthalic acid and diphenyl-p,p'-disulphonic acid with 2,2-di(4-hydroxyphenyl)-propane Copolyester of diphenyl-p,p'-disulph0nic acid and diphenyl ether-p,p'-disulphonic acid with 2,2-di(4-hydroxyphenyl)-propane and 2,2-di(4-hydroxyphenyl)-butane
  • Copolyester of 2,2-di(4-hydroxy-3,S-dibromophenyl)-propane and 2,2-di(4-hydroxyphenyl)-propane with isophthalic acid isophthalic acid.
  • Copolyester of fluorene-3,6-disulphonic acid and diphenylp,p-disulphonic acid with 2,2-di(4-hydroxyphenyl)- propane
  • Cellulose-derivatives such as, e.g., Cellulose-aceto-N-phenylcarbamate, Cellulose-acetocinnamate.
  • thermoplastic photoconductive polymers may be employed in combination with substances increasing their sensitivity, such substances are, e.g., mentioned in the British patent specifications 964,871-964,875 and 964,877.
  • the tape may consist solely of self-supported photoconductive polymeric material or it may consist of the photoconductive polymeric material coated upon a high melting base film such as one sold under the trademark Mylar or Cronar, for example. In either case, it is necessary that the photoconductive polymeric layer be in intimate surface contact with a conductive backing. Any metallic or similar conductor, such as copper or aluminium for example, may be employed. Should the tape comprise a self-supporting photoconductive polymeric material, its thickness should be sufiicient to allow heating of the surface on which information is recorded only to a fraction of the thickness, so that the tape will remain in a selfsupporting state. Unually tapes of a thickness of 10 to p. will suffice.
  • Recordation of information can be achieved simply, economically and efiiciently by any method involving exposure of the photoconductive material to a pattern of electro-magnetic radiation rendering the polymer conductive and by bringing about a charge condition of the unexposed areas.
  • the recording medium may be uniformly charged by passing thereover a corona generating device. Either a positive or negative electrostatic charge may be laid upon the film. Subsequently, the charged film is image-wise exposed to electromagnetic radiation of suitable wavelength. The radiation struck areas of the photoconductor, being rendered conductive thereby, charge is carried oil. The unexposed areas of the film remain charged.
  • the photoconductive film may first be exposed image-wise to electromagnetic radiation, thus rendering the light struck areas conductive and subsequently, uniformly charged with a corona generating device. No charge will be laid down on the conductive, radiation struck areas of the film and an image comparable to that produced by the method described above will occur.
  • Reproduction of the recorded image may be accomplished by means of any conventional optical projection system.
  • any conventional optical projection system For example, a system based upon the principles of phase diffraction grating whereby visible light, diffracted by the ripples in the photoconductive medium is permitted to shine upon a screen while light which passes through smooth, nondeformed areas of the film is not permitted to shine upon the screen, a visible reproduction of the recorded information is produced.
  • the recorded electrostatic latent image in the photoconductive layer should be built up line-wise by exposure, e.g., to a light spot of a flying spot scanner. Such a method will yield a ripple image adapted for reproduction in a phase diffraction system. It is to be understood, however, that any suitable and conventional optical projection system may be employed to reproduce the ripple image.
  • thermoplastic layer of the following composition:
  • the dried photoconductive layer has a thickness of 1.5 to 2 microns.
  • the material is charged by means of a corona generating device and a latent electrostatic record of information is created by selectively carrying otf electric charge from the material using a light spot (flying spot scanner).
  • the material is then heated to the melting point of the polymeric material and after the deformations have set in according to the charge pattern, the material is cooled to freeze the deformations.
  • Reproduction of the image is accomplished by employing projection apparatus such as that described by W. E. Glenn.
  • the material is erased by melting the polymeric material above its melting point while exposing it to light. Subsequent, recordations on the erased tape by this same described method, produced excellent images.
  • a process for recording optical information on a deformable layer in the form of a relief pattern which comprises electrostatically charging a layer of a thermoplastic photoconductive polymeric layer superimposed upon a layer of conductive material before or after said layer is subjected to electromagnetic radiation to which said photoconductive layer is sensitive in a pattern according to said information to be recorded so as to produce on said layer an electrostatic charge pattern in accordance with the information to be recorded, heating said material to a degree suflicient to soften at least the surface layer of the polymeric said layer whereby said softened surface layer is deformed physically under the influence of the electrostatic forces existing between the charge pattern at the surface of said photoconductive layer and said conductive layer, and cooling said heated layer to fix the deformations therein.
  • polymeric layer additionally contains a radiation sensitive substance.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
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Description

United States Patent 3,441,947 THERMOPLASTIC RECORDING PROCESS Ulrich Schmiedel, Hamburg, Germany, Louis Achille Meeussen and Paul Maria Cassiers, Mortsel-Antwerp,
and Rene Maurice Hart, Wilrijk-Antwerp, Belgium;
said Meeussen, said Cassiers, and said Hart, assignors to Gevaert Photo-Producten N.V., Mortsel, Belgium, a
Belgian company No Drawing. Continuation-impart of application Ser. No.
110,342, May 16, 1961. This application Oct. 7, 1965,
Ser. No. 493,866 Claims priority, application Great Britain, May 17, 1960,
17,452/ 60 Int. Cl. G01d /14, 15/12 U.S. Cl. 346-74 9 Claims This application is a continuation-in-part of application Ser. No. 110,342, filed May 16, 1961, and now abandoned.
This invention relates to novel methods for recording and reproducing information.
According to a recently proposed method (W. E. Glenn, Journal of Applied Physics, volume 30, pages 1870-1873, 1959), information is recorded in the form of deformations or ripples in the surface of a thermoplastic tape. The information can be detected optically by projecting light through these ripples to form a visible image on a screen. The tape consists of a high melting base film coated with a metallic conducting layer which is in turn coated with the low melting thermoplastic material. By means of an electron gun, information can be written on the surface of the thermoplastic layer in the form of a charge pattern. Upon heating the tape above the melting point of the thermoplastic material, electrostatic forces between the charge pattern and the metallic, conductive layer caused deformations or ripples in the tape surface. Cooling the tape below the melting point of the thermoplastic material freezes these deformations, thus yielding a permanent record of the recorded information. A modi- -fied Schlieren optical system is employed to project the recorded information on a screen. The tape may be erased for reuse by heating the film above its melting point for a period of time suificient to allow the charge pattern to drain away and to allow the surface tension of the thermoplastic layer to smooth out the deformations.
Throughout the specification the phrase, thermoplastic recording process, will be employed to indicate the process described.
The Glenn process suffers from the disadvantage that the employment of an electron gun to record information requires the maintenance of vacuum conditions. This necessitates the employment of additional bulkier apparatus which results in a more expensive and less efficient process.
It is an object of the present invention to overcome this inherent deficiency in the Glenn process.
It is a further object of the present invention to provide an eflicient method for the recordation and reproduction of information.
It is a further object of the present invention to provide an information recordation process which constitutes an improvement over the Glenn process.
These and further objects are realized, according to the present invention, by effecting the thermoplastic recordation of information on a photoconductive, polymeric material.
The method according to the present invention may be described broadly as follows.
Instead of the thermoplastic film material employed by Glenn, the method of the present invention utilizes a low melting, thermoplastic, photoconductive, polymeric material. Thus, the tape consists of a high melting base 3,441,947 Patented Apr. 29, 1969 ice film coated with a thin, conductive layer which is in turn coated with a photoconductive polymeric layer. The use of a photoconductive, polymeric material enables simpler, more efficient recording apparatus than has been heretofore possible in thermoplastic recording processes.
It is well known that the conductivity of a photoconductive material is increased by exposure to visible electromagnetic radiation. This characteristic of photoconductive materials enables recordation of information in the form of charge patterns in these materials.
In the method according to the present invention, for example, a uniform electrostatic charge is placed on the surface of the photoconductive layer of the thermoplastic tape by exposure to a charging device, such as a corona generating device. Upon exposure to a radiation image, the charge in the exposed areas of the tape is dissipated by virtue of the selective increase in conductivity in these areas. The tape then contains an image in the form of a charge pattern. The tape is then further processed in the manner according to Glenn by first, heating the tape above the melting point of the photoconductive layer to allow deformations or ripples to form in the surface of the tape; second, cooling the tape to freeze these ripples into a permanent record and third, optically detecting the recorded information in a suitable projection apparatus.
It is readily apparent, that the method of the present invention constitutes an improvement over the prior art process. Thus, the need for bulky, expensive and inefficient vacuum equipment is eliminated. The method of the present invention merely involves simple charging and exposure operations which can be carried out with simple equipment under atmospheric pressure condition. The present method is therefore less expensive, more efiicient and less complicated than the prior art methods.
Photoconductive polymeric materials useful in the process of the present invention include any macromolecular substance or any mixture of macromolecular substances which on exposure to radiation of suitable wavelength exhibits an increase in conductivity. The following classes of polymeric substances have been found to be especially useful:
A. Vinylpolymers and related compounds, i.e.,
(1) Vinyl polymers with acetal groups, such as, e.g.,
Po1y*(vinyl formal) Poly (vinyl acetal) Poly(vinyl butyral) (2) Vinyl polymers with unsaturated compounds in the side chain such as, e.g.,
=(a) Poly(vinyl cinnamate),
(b) Vinyl polymers and copolymers containing or consisting of recurrent units of the following general formula:
wherein:
A represents a divalent radical such as NHCO, NHCONH or 0C0;
R represents a hydrogen atom or a substituent of the aromatic nucleus such as methoxy group; and
R represents a hydrogen atom or a methyl group, such as, e.g.,
Poly (4-methacrylyloxy) -stilbene] Poly p- N'-vinylureido -stilbene] Poly [4-methoxy-4'- (N-acrylyl -aminostilbene] Copolymer of vinyl acetate and p-(N-vinylureido)-stilbene,
(3) Vinyl polymers and copolymers containing a heterocyclic or an aromatic polycyclic nucleus in the side chain.
(a) Vinyl polymers and copolymers containing or consisting of recurrent units of the following general formula:
mo A R H I -1 N wherein A represents a divalent radical such as NHCO, CH=N or NHCONH; Y represents an oxygen atom or a sulfur atom; and R represents a hydrogen atom or a methyl group, such as, e.g.,
Poly[2-methyl-6-(N-acrylyl)-aminobenzoxazole], reaction product of polyacroleine and 2-methyl- 6-aminobenzoxazole, Poly [2-methyl-6- N'-vinylureido -benzoxazole] Poly(Z-methyl-6-acrylyl-aminobenzothiazole), Copolymer of vinylacetate, and 2-methyl-6-(N'- vinyl-ureido)-benzoxazole, Copolymer of styrene and 2-methyl-6-(N'-vinylnreido)-benzoxazole, Copolymer of ethyl arcrylate and 2-methyl-6-(N- acrylamino)-benzothiazole, Poly[2 methyl 6 (N'-viny1) ureido benzothiazole], Copolymer of 2-methyl-6-(N'-vinyl)-ureido-ben zothiazole and vinyl acetate, Copolymer of 2-methyl-6-(N'-vinyl)-ureido-benzothiazole and ethyl acrylate. (b) Vinyl polymers and copolymers containing or consisting of recurrent units of the following general formula:
wherein:
A represents a divalent radical such as or a single bond;
Q and Q each represents a hydrogen atom, a methyl radical, a nitro group, a phenyl group, a substituted phenyl group, or form together the atoms necessary to close a ring;
R represents a hydrogen atom or a methyl group;
X=N or a methine group; and
:8, O, imino group, isopropylidene group, dimethine group or a substituted dimethine group, such as, e.g.,
Poly[2 (4'-acrylyloxy-phenyl) 4 (4"-dimethylaminophenyl)-5-phenyl-imidazole],
Poly[2 (4'-methacrylyloxyphenyl) 4 (4"-dimethylaminophenyl -5-phenylimidazole] Poly[2 (2'-N-acrylylaminophenyl) 4,5 diphenylimidazole],
4 Poly[l (2'-methacrylyl-oxyethyl) 2,4,5 triphenylimidazole], Poly(2 vinyl 3 isopropylidene 5 dimethylpyrroline), 5 Reaction product of polyacrolein and 2-aminothiazole, Reaction product of polyacrolein and Z-amino-S- nitrothiazole, Reaction product of polyvinylamine and 4-pyridine aldehyde,
Reaction product of polyvinylamine and 2-quinoline aldehyde,
Poly[p-(2-quinoline-4-carboxylic acid) styrene],
Copolymer of styrene and 2-(2'-N'-vinylureido)- phenyl-4,S-diphenylimidazole,
Poly(2-vinyl benzoxazole),
Poly(2-vinyl benzothiazole),
Poly[2 (4'-acrylyloxyphenyl) 4,5 diphenylimidazole],
Poly[2 (2'-acrylyloxynaphthyl) 4 phenyl 5- (4-dimethylaminophenyl -imidazole] (c) Vinyl polymers consisting of or containing recurring units of the following general formula:
wherein:
A represents a single bond or CH CH OCO; Q Q and Q each represents a hydrogen atom or a phenyl nucleus; and R represents a hydrogen atom or a methyl group, such 4 as, e.g.,
Polyvinyl imidazole, Poly[l (2'-methacrylyloxyethyl) 2,4,5 tri phenylimidazole] (d) Vinyl polymers consisting of or containing recu ring units of the following general formula:
A represents N=CH or CH=N;
Q and Q together represent the atoms necessary to close an aromatic nucleus;
Y represents a single bond, 3. sulphur atom or a carbonyl Z represents a carbonyl group or a nitrogen atom substituted by a lower alkyl radical; and R represents a hydrogen atom or a methyl group, such as, e.g.,
Reaction product of polyvinyl amine and N-methylphenothiazine-Z-aldehyde, Reaction product of polyvinyl amine and N-ethylcarbazole-Z-aldehyde, Reaction product of polyacrolein and l-aminoanthraquinone, Reaction product of polyacrolein and 3-arninocarbazole. (f) Other vinyl polymers and copolymers containing a heterocyclic or aromatic polycyclic nucleus in the side chain:
Poly [2- 1-acrylyloxyethyl -fiuorene] Poly [4-vinylphenyl-2- N-ethylcarbazyl -carbinol] Poly[ 1,3-diphenyl-5- (4-acr1yloxyphenyl -2-pyrazoline] (4) Vinyl polymers containing a diarylmethane group in the side chain, such as poly(p-vinyl-p'-dimethylaminodiphenyl-carbinol) (5 Vinyl polymers and copolymers such as Terpolymer of vinyl chloride, vinyl acetate and vinyl alcohol,
Terpolymer of vinyl chloride, vinyl acetate and maleic anhydride,
Nitrated terpolymer (vinyl acetate/styrene/maleic anhydride),
Copolymer of vinyl acetate and mono-n-decylinaleate.
(6) Vinyl polymers and copolymers containing or consisting of recurrent units of the following general formula:
A represents a single bond, or a divalent organic radical such as, e.g.,
-CH2-, CH CH -COO-, -CH -CH CH O-CO-, -CH2CH2-COC6H4, -CH -C H R and R each represents a hydrogen atom or a lower alkyl radical such as, e.g., a methyl radical; Z represents a sulphur atom or a single bond; Z represents a rnethine group or a nitrogen atom; Q and Q together represent the atoms necessary to complete an aromatic nucleus; and Q and Q together represent the atoms necessary to complete an aromatic nucleus, such as, e.g.,
Poly (9-methacrylyloxyf1uorene) Poly(N-acrylylphenothiazine Poly [N Z-acrylyloxy-ethyl -phenothiazine] Poly(N-allyl carbazole) Poly [N-( Z-acrylyloxypropyl -phenothiazine] Poly(N-Z-acrylyloxy-2-methyl-N-ethyl carbazole), Poly [N (Z-pwinylbenzoylyethyl -carbazole] Poly(N-propenyl carbazole), Poly(N-vinyl carbazole) Poly [N- (Z-methacrylyloxypropyl -carb azole] Poly [N- acrylyl -carb azole] Poly [4-vinyl-a- (N-carbazyl -toluene] M01 percent of N-vinyl carbazole Copolymer of N-vinyl carbazole and vinylidene Copolymer of N-vinyl carbazole and vinyl acetate 88.6 Copolymer of N-vinyl carbazole and isopropenyl acetate Mol percent of N-vinyl carbazole Copolymer of N-vinyl carbazole and vinylstearate 37.5 Copolymer of N-vinyl carbazole and methyl acrylate 67.6 Copolymer of N-vinyl carbazole and methyl acrylate 4l Graft copolymer of N-vinyl carbazole and poly(ethyl acrylate) 90.3 Emulsion polymer of N-vinyl carbazole and ethyl acrylate 94.5 Copolymer of N-vinyl carbazole and m-butyl acrylate 58.3 Copolymer of N-vinyl carbazole and Z-ethyl-hexyl acrylate 51.6 Copolymer of N-vinyl carbazole and acrylyloxyethyl diethylamine 76.6 Copolymer of N-vinyl carbazole and vinylcinnamate 92.5 Copolymer of N-vinyl carbazole and ethylmethacrylate 62.7 Copolymer of N-vinyl carbazole and isobutyl methacrylate 51.8 Copolymer of N-vinyl carbazole and lauryl methacrylate 77.4 Copolymer of N-vinyl carbazole and methacrylyloxyethyl diethylamine 9.7 Copolymer of N-vinyl carbazole and acrylonitrile 88 Graft copolymer of N-vinyl carbazole and butyraldehyde acetal of polyvinyl alcohol 59 Copolymer of N-vinyl carbazole and di(2-chloroethy1)-vinyl phosphonate 82.4 Copolymer of N-vinyl carbazole and styrene 49 Graft copolymer of N-vinyl carbazole and polystyrene 27.3
Copolymer of N-vinyl carbazole and vinylnaphthalene 47.1 Copolymer of N-vinyl carbazole and anthracene-(9,
10) Copolymer of N-vinyl carbazole and 2-vinyl pyridine Copolymer of N-vinyl carbazole and 4-vinyl pyridine Copolymer of N-vinyl carbazole and N-vinyl pyrrolidone Terpolymer of N-vinyl carbazole, acrylonitrile and styrene Graft copolymer of a terpolymer of vinyl chloride,
vinyl acetate and vinyl alcohol with N-vinyl carbazole Graft copolymer of a terpolymer of vinyl chloride, vinyl acetate and maleic anhydride with N-vinyl carbazole 55.1
(7) Vinyl polymers and copolymers containing or con sisting of recurrent units of the following general formula:
A represents an aromatic nucleus such as, e.g., a benzene nucleus or a heterocyclic nucleus such as a carbazole nucleus;
B represents an aromatic nucleus such as e.g., a benzene, a naphthalene or anthracene nucleus, or a heterocyclic nucleus such as, e.g., a carbazole, phenothiazine or quinoline nucleus;
R represents a hydrogen atom or a lower alkyl radical such as, e.g., a methyl radical; and
n and m each represents a positive integer from 1 to 2,
such as, e.g.,
Poly(vinyl benzal acetophenone),
Poly(vinyl cinnamal acetophenone) Poly(vinyl anisal acetophenone),
Reaction product of poly(vinyl acetophenone),
and p-dimethylaminocinnamaldehyde,
Reaction product of poly(viny1 acetophenone) and l-naphthaldehyde,
Reaction product of p0ly(vinyl acetophenone) and 9-anthraldehyde,
(8) Polymers and copolymers obtained by reacting halogenated polymers or copolymers with compounds containing an aromatic nucleus or by reacting one or more halogenated monomers with polymeric substances containing aromatic groups, such as e.g.
Reaction product of polyvinyl chloride and anthracene,
Reaction product of polyvinyl chloride and fluorene,
Reaction product of polyvinyl chloride and naphthalene,
Reaction product of polyvinyl chloride and toluene,
Reaction product of polyvinyl chloride and N-methylphenothiazine,
Reaction product of polyvinyl chloride and carbazole,
Reaction product of polyvinyl chloride and phenothiazine,
Reaction product of polyvinyl chloride and N-ethyl carbazole,
Reaction product of polyvinyl chloride and phenoxathine,
Reaction product of polyvinyl chloride and acridine,
Reaction product of polyvinyl chloride and lophine,
Reaction product of after-chlorinated polyvinyl chloride and anthracene,
Reaction product of chlorinated natural rubber and anthracene,
Reaction product of after-chlorinated polyvinyl chloride and naphthalene,
Reaction product of chlorinated natural rubber and naphthalene,
Reaction product of polyvinyl benzylbromide and N-ethyl carbazole,
Reaction product of the copolymer of vinyl chloride and styrene with naphthalene. B. Polyesters, such as, e.g.,
Polyester of 2,2-di(4-hydroxyphenyl)-propane and isophthalic acid,
Polyester of benzene-1,3-disulphonic acid and 2,2-di(4- hydroxyphenyl -prop ane,
Polyester of diphenyl-p,p'-disulphonic acid and 2,2-(4- hydroxyphenyl -propane,
Polyester of 2,2-di(3-methyl-4-hydroxyphenyl)-propane and stilbene discarboxylic acid,
Polyester of 4,4'-dicarboxydiphenyl and neopentyl glycol,
Polyester of isophthalic acid and di(4-hydroxyphenyl)- methylphenylmethane,
Polyester of di(4-hydroxyphenyl)-phenylt1nethane and benzophenon-4,4'-dicarboxylic acid,
Polyester of diphenyl ether-p,p-disulphonic acid and 2,2-
di (4-hydroxyphenyl -prop ane,
Polyester of diphenyl ether-4,4'-disulphonic acid and di(4- hydroxyphenyl) -phenylm ethane,
Polyester of diphenyl-4,4'-disulphonic acid and 4,4'-di(4- hydroxyphenyl) methylphenylmenthane,
Polyester of diphenyl-4,4'-disulphonic acid and 2,2-di(4- hydroxyphenyl) -butane,
Polyester of diphenyl-p,p'-disulphonic acid and 3,3'-di(4- hydroxyphenyl) -p entane,
Polyester of l,3-diphenylpropane-p,p-dicarboxylic acid and 2,2-di (4-hydroxyphenyl -prop ane,
Polyester of diphenyl-p,p'-disulphonic acid and 2,2-di(3- methyl-4-hydroxyphenyl)-propane,
Polyester of diphenyl-p,p-disulphonic acid and 2,2-di(4- hydroxy-3,S-dichlorophenyl) -propane,
Polyester of diphenyl-p,p'-disulphonic acid and 2,2-di(p hydroxyphenyl) -4-methy1-pentane,
Polyester of diphenyl-p,p'-disulphonic acid and l,1-di(3- methyl-4-hydroxyphenyl) -cyclohexane,
Copolyester of 2,2 di(4-hydroxyphenyl)-propane and isophthalic acid with terephthalic acid,
Copolyester of diphenyl ether-p,p'-dicarboxylic acid with diphenyl-p,p-disulphonic acid with 2,2-di(4-hydroxyphenyl) -prop ane,
Copolyester of terephthalic acid and diphenyl-p,p'-disulphonic acid with 2,2-di(4-hydroxyphenyl)-propane, Copolyester of diphenyl-p,p'-disulph0nic acid and diphenyl ether-p,p'-disulphonic acid with 2,2-di(4-hydroxyphenyl)-propane and 2,2-di(4-hydroxyphenyl)-butane,
Copolyester of diphenyl-p,p-disulphonic acid and terephthalic acid with 2,2-di(3-methyl-4-ihydroxyphenyl)- propane,
Copolyester of terephthalic acid and isophthalic acid with 2,2-di(4-hydroxy-3,5-dichloro phenyl)-propane,
Copolyester of 2,2-di(4-hydroxy-3,S-dibromophenyl)-propane and 2,2-di(4-hydroxyphenyl)-propane with isophthalic acid.
Copolyester of fluorene-3,6-disulphonic acid and diphenylp,p-disulphonic acid with 2,2-di(4-hydroxyphenyl)- propane.
C. Cellulose-derivatives such as, e.g., Cellulose-aceto-N-phenylcarbamate, Cellulose-acetocinnamate.
The thermoplastic photoconductive polymers may be employed in combination with substances increasing their sensitivity, such substances are, e.g., mentioned in the British patent specifications 964,871-964,875 and 964,877.
The tape may consist solely of self-supported photoconductive polymeric material or it may consist of the photoconductive polymeric material coated upon a high melting base film such as one sold under the trademark Mylar or Cronar, for example. In either case, it is necessary that the photoconductive polymeric layer be in intimate surface contact with a conductive backing. Any metallic or similar conductor, such as copper or aluminium for example, may be employed. Should the tape comprise a self-supporting photoconductive polymeric material, its thickness should be sufiicient to allow heating of the surface on which information is recorded only to a fraction of the thickness, so that the tape will remain in a selfsupporting state. Unually tapes of a thickness of 10 to p. will suffice.
Recordation of information can be achieved simply, economically and efiiciently by any method involving exposure of the photoconductive material to a pattern of electro-magnetic radiation rendering the polymer conductive and by bringing about a charge condition of the unexposed areas. 'For example, the recording medium may be uniformly charged by passing thereover a corona generating device. Either a positive or negative electrostatic charge may be laid upon the film. Subsequently, the charged film is image-wise exposed to electromagnetic radiation of suitable wavelength. The radiation struck areas of the photoconductor, being rendered conductive thereby, charge is carried oil. The unexposed areas of the film remain charged.
Alternatively, the photoconductive film may first be exposed image-wise to electromagnetic radiation, thus rendering the light struck areas conductive and subsequently, uniformly charged with a corona generating device. No charge will be laid down on the conductive, radiation struck areas of the film and an image comparable to that produced by the method described above will occur.
The advantages of such a system over that described by Glenn are obvious. There is no need for bulky, expensive and inefficient vacuum apparatus or an electron gun for producing the desired image. Only a simple charge generating device and a source of electromagnetic radiation are necessary. Furthermore, the nature of the photoconductive polymeric material makes it possible to render the recording medium completely self-supporting without need for a base material.
Development of the recorded image and its reproduction may be accomplished in the same manner as that disclosed by Glenn. By merely heating the photoconductive polymer above its melting point, electrostatic attraction between charges on the film and its conductive backing will cause deformations or ripples in its surface. Cooling the medium below the melting point, will freeze these ripples into a permanent record.
Reproduction of the recorded image may be accomplished by means of any conventional optical projection system. For example, a system based upon the principles of phase diffraction grating whereby visible light, diffracted by the ripples in the photoconductive medium is permitted to shine upon a screen while light which passes through smooth, nondeformed areas of the film is not permitted to shine upon the screen, a visible reproduction of the recorded information is produced. For optimum results, the recorded electrostatic latent image in the photoconductive layer should be built up line-wise by exposure, e.g., to a light spot of a flying spot scanner. Such a method will yield a ripple image adapted for reproduction in a phase diffraction system. It is to be understood, however, that any suitable and conventional optical projection system may be employed to reproduce the ripple image.
EXAMPLE On an electrically conducting metallic backing is cast a photoconductive thermoplastic layer of the following composition:
Polypropenyl carbazole g 8 Ester gum g 2 Methylene chloride cc 100 The dried photoconductive layer has a thickness of 1.5 to 2 microns.
The material is charged by means of a corona generating device and a latent electrostatic record of information is created by selectively carrying otf electric charge from the material using a light spot (flying spot scanner). The material is then heated to the melting point of the polymeric material and after the deformations have set in according to the charge pattern, the material is cooled to freeze the deformations.
Reproduction of the image is accomplished by employing projection apparatus such as that described by W. E. Glenn. The material is erased by melting the polymeric material above its melting point while exposing it to light. Subsequent, recordations on the erased tape by this same described method, produced excellent images.
What we claim is:
1. A process for recording optical information on a deformable layer in the form of a relief pattern, which comprises electrostatically charging a layer of a thermoplastic photoconductive polymeric layer superimposed upon a layer of conductive material before or after said layer is subjected to electromagnetic radiation to which said photoconductive layer is sensitive in a pattern according to said information to be recorded so as to produce on said layer an electrostatic charge pattern in accordance with the information to be recorded, heating said material to a degree suflicient to soften at least the surface layer of the polymeric said layer whereby said softened surface layer is deformed physically under the influence of the electrostatic forces existing between the charge pattern at the surface of said photoconductive layer and said conductive layer, and cooling said heated layer to fix the deformations therein.
2. The process of claim 1 wherein said polymeric layer is uniformly charged and subsequently exposed to said electromagnetic radiation image.
3. The process of claim 1 wherein said polymeric layer is exposed to said electromagnetic radiation image and subsequently uniformly charged.
4. The process of claim 1 wherein said. polymeric layer is in the form of a tape.
5. The process of claim 4 wherein said tape comprises of high melting base layer coated with said polymeric layer.
6. The process of claim 4 wherein said tape comprises of self-supporting layer of said photopolymer.
7. The process of claim 1 wherein said conductor is in the form of a coating on said photopolymer.
8. The process of claim 1 wherein said recorded image is built up line-wise by means of a light spot of a flying spot scanner.
9. The process of claim 1 wherein polymeric layer additionally contains a radiation sensitive substance.
References Cited UNITED STATES PATENTS 2,896,507 7/1959 Mast 88-61 3,055,006 9/1962 Dreyfoos 34674 3,284,196 11/1966 MaZZa 96--l.1
TERRELL W. FEARS, Primary Examiner.
US. Cl. X.R.

Claims (1)

1. A PROCESS FOR RECORDING OPTICAL INFORMATION ON A DEFORMABLE LAYER IN THE FORM OF A RELIEF PATTERN, WHICH COMPRISES ELECTROSTATICALLY CHARGING A LAYER OF A THERMOPLASTIC PHOTOCONDUCTIVE POLYMERIC LAYER SUPERIMPOSED UPON A LAYER OF CONDUCTIVE MATERIAL BEFORE OR AFTER SAID LAYER IS SUBJECTED TO ELECTROMAGNETIC RADIATION TO WHICH SAID PHOTOCONDUCTIVE LAYER IS SENSITIVE IN A PATTERN ACCORDING TO SAID INFORMATION TO BE RECORDED SO AS TO PRODUCE ON SAID LAYER AN ELECTROSTATIC CHARGE PATTERN IN ACCORDANCE WITH THE INFORMATION TO BE RECORDED, HEATING SAID MATERIAL TO A DEGREE SUFFICIENT TO SOFTEN AT LEAST THE SURFACE LAYER OF THE POLYMERIC SAID LAYER WHEREBY SAID SOFTENED SURFACE LAYER IS DEFORMED PHYSICALLY UNDER THE INFLUENCE OF THE ELECTROSTATIC FORCES EXISTING BETWEEN THE CHARGE PATTERN AT THE SURFACE OF SAID PHOTOCONDUCTIVE LAYER AND SAID CONDUCTIVE LAYER, AND COOLING SAID HEATED LAYER TO FIX THE DEFORMATIONS THEREIN.
US3441947D 1960-05-17 1965-10-07 Thermoplastic recording process Expired - Lifetime US3441947A (en)

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GB2348660A GB964881A (en) 1960-05-17 1960-05-17 Improvements in or relating to electrostatic records
GB1745260A GB964880A (en) 1960-05-17 1960-05-17 Improvements in or relating to electrostatic recording

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4233380A (en) * 1972-03-17 1980-11-11 Hoechst Aktiengesellschaft Process for shaping a thermoplastic layer

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2896507A (en) * 1952-04-16 1959-07-28 Foerderung Forschung Gmbh Arrangement for amplifying the light intensity of an optically projected image
US3055006A (en) * 1961-01-24 1962-09-18 Ibm High density, erasable optical image recorder
US3284196A (en) * 1962-10-11 1966-11-08 Ibm Apparatus and method for electric recording

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2896507A (en) * 1952-04-16 1959-07-28 Foerderung Forschung Gmbh Arrangement for amplifying the light intensity of an optically projected image
US3055006A (en) * 1961-01-24 1962-09-18 Ibm High density, erasable optical image recorder
US3284196A (en) * 1962-10-11 1966-11-08 Ibm Apparatus and method for electric recording

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4233380A (en) * 1972-03-17 1980-11-11 Hoechst Aktiengesellschaft Process for shaping a thermoplastic layer

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GB964881A (en) 1964-07-22

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