Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
  • B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
  • B41M5/40—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used characterised by the base backcoat, intermediate, or covering layers, e.g. for thermal transfer dye-donor or dye-receiver sheets; Heat, radiation filtering or absorbing means or layers; combined with other image registration layers or compositions; Special originals for reproduction by thermography
  • B41M5/42—Intermediate, backcoat, or covering layers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
  • B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
  • B41M5/30—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used using chemical colour formers
  • B41M5/337—Additives; Binders
  • B41M5/3372—Macromolecular compounds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
  • B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
  • B41M5/40—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used characterised by the base backcoat, intermediate, or covering layers, e.g. for thermal transfer dye-donor or dye-receiver sheets; Heat, radiation filtering or absorbing means or layers; combined with other image registration layers or compositions; Special originals for reproduction by thermography
  • B41M5/42—Intermediate, backcoat, or covering layers
  • B41M5/423—Intermediate, backcoat, or covering layers characterised by non-macromolecular compounds, e.g. waxes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
  • B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
  • B41M5/40—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used characterised by the base backcoat, intermediate, or covering layers, e.g. for thermal transfer dye-donor or dye-receiver sheets; Heat, radiation filtering or absorbing means or layers; combined with other image registration layers or compositions; Special originals for reproduction by thermography
  • B41M5/42—Intermediate, backcoat, or covering layers
  • B41M5/44—Intermediate, backcoat, or covering layers characterised by the macromolecular compounds
• • 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
  • Y10S428/00—Stock material or miscellaneous articles
  • Y10S428/913—Material designed to be responsive to temperature, light, moisture
• • 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
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/31504—Composite [nonstructural laminate]
  • Y10T428/31801—Of wax or waxy material
  • Y10T428/31804—Next to cellulosic
  • Y10T428/31808—Cellulosic is paper

Definitions

• an improved heatsensitive record material wherein such material, comprises: (1) a base sheet such as paper; (2) a coating of finely dispersed acidic particles such as a di-phenol, finely dispersed colorless chromogenic particles such as a benzoindolinospiropyran derivative which give color when in liquid contact with an acidic material, and a film-forming polymeric material such as polyvinyl alcohol to act as a matrix for the two color-forming reactants; and 0ptionally; (3) a protective overcoat such as a film of polyvinyl alcohol which may also have soditun carboxy methyl cellulose present in it to give a proper viscosity to the coating slurry for ease in machine application; is made resistant to pick-off of the record sheet surface and freezesticking of the record sheet to the printing head when the record material is used in conjunction with a rapidly heated and cooled printing head, particularly one of the planographic
• the improvement consists of providing the heat-sensitive record material with a lubricating overcoat comprising a film of hydrophilic, polymeric material, such as polyvinyl alcohol (with or without added sodium carboxy methyl cellulose), having dispersed therein to the extent of about 2% fine particles of a lubricating or nontacky wax, melting about 140 C.; optionally a primer coat of the same composition; and finally as a further option an added dispersion of calcium stearate in the coating or layer which bears the colorforming coreactants.
• a lubricating overcoat comprising a film of hydrophilic, polymeric material, such as polyvinyl alcohol (with or without added sodium carboxy methyl cellulose), having dispersed therein to the extent of about 2% fine particles of a lubricating or nontacky wax, melting about 140 C.; optionally a primer coat of the same composition; and finally as a further option an added dispersion of calcium stearate in the coating or layer which bears the colorforming core
• This invention relates to heat-sensitive coated record material that will not pick-01f onto hot type surfaces.
• Heat-sensitive record materials of the type shown in an application for Letters Patent of the United States, Ser. No. 366,524, filed by Henry H. Baum on May 11, 1964, owe their heat-sensitive characteristics to a thermoplastic film coating which contains in it heat-responsive chemically reactive color-producing material in dispersed solid particulate form.
• the flowing together of these materials under conditions of the coatings being subjected to a printing contact with hot type causes coloration of the film coating at the typed points.
• planographic surface printing plates or surfaces that have heatable matrices flush with the lano-surface, which matrices are selectively operable by flash heating to print the selected symbol.
• These symbols may be made up of selected elements of a Solomons Seal type of matrix, which elements are, individually for an instant, rendered very hot (250 degrees centigrade) and suddenly cooled by heat conduction into a heat sink to make them ready for printing another selected symbol, the record material being advanced or moved across the printing plate between symbol-printing operations to form a contextual data message.
• the heating and sudden cooling of the type face may freeze the melted film to the printer plate, re-
• a preferred embodiment of a pair of heat-sensitive reactants selected from among those appearing in the Baum disclosure, and as used in a coating system for the purpose of providing the anti-pick record material of this invention is the pair comprising, as the color reactants, (a) the chromogenic material ture and having a melting point of 156 degrees centigrade.
• This acidic material will be called Bis phenol A, as it is commonly sold under that designation.
• reactants may be dispersed as solid fine particles in a water solution of a suitable grade If polyvinyl alcohol and water-wettable calcium stearate, and the dispersion may be applied to and subsequently dried on a prepared paper sheet to produce a heat-sensitive coating which responds by blue coloration to hot type pressed thereagainst.
• This coated sheet has the infirmity, however, of sticking to or picking-off onto a planographic type surface having rapidly heating and cooling configurations adjacent to constantly cool areas (room temperature) across which the sheet is passed step by step.
• the damage to the record is more apparent with finer printing than with larger printing, as would be obvious, so the invention is mainly directed to a pressing problem with fineprinting species of planar printing heads.
• the printing head itself, by picking up the coating, is likewise subject to fouling and consequently is rendered incapable of giving a sharp print.
• Acra Wax C is a reaction product of hydrogenated castor oil and ethanola-mine, is insoluble in boiling water, and has a melting point of to 143 degrees centigrade, a flash point of 285 degrees centigrade (open cup), and a specific gravity of 0.97 at 25 degrees centigrade. It may be purchased as a fine powder under the quoted brand name from Glyco Chemicals, Inc., 417 Fifth Avenue, New York, N.Y., United States of America. Although Acra Wax C has been specified as preferred, any similar anti-blocking wax or nontacky wax in powdered form and insoluble in water may be used and will be specified in the claims as nontacky Wax.
• the calcium stearate used is of fine powder particle size and has water-Wettable characteristics to permit of its dispersion in a water solution of polyvinyl alcohol.
• a suitable material is the Disperso grade of Witco Chemical Company, Inc., 122 East Forty-Second Street, New York, N.Y., United States of America, but the controlling factor in its selection, from whatever source it is obtained, is that of its dispersibility in water, so the preferred embodiment will be specified as water-dispersible calcium stearate powder.
• the polyvinyl alcohol preferred for the substrate coating (or primer) is a medium-viscosity grade of 99% hydrolysis, and this grade also is used for the overcoating. while one of 98% hydrolysis is used for the middle layer, containing the calcium stearate and the dispersed mixture of color reactants.
• Water solutions of the specified polyvinyl alcohols gel at room temperature (20 to 25 degrees centigrade).
• Polyvinyl alcohols of this type can be purchased as Elvanol brand from E. I. DuPont de Ncmours and Company, Inc., of Wilmington, Del., United States of America, their grade 71-30 being of 99% hydrolysis and their grade 71-24 being of 98% hydrolysis.
• the medium-viscosity range of these materials lies between 23 and 32 centipoises in a 4% water solution at 20 degrees centigrade as determined by the Hoeppler falling-ball method.
• the primer and the top coating composition contain sodium carboxy methyl cellulose, with enough sodium carboxymethyl groups to make it water-soluble.
• This kind of material and the process of making it are set out in the pamphlet Hercules Cellulose Gum Properties and Uses, printed and copyrighted in 1960 by Hercules Powder Company, Wilmington, Del., United States of America. It lends a coating viscosity property to the coating composition as a whole, but, as it is not an essential in the coloror mark-forming property of the record material, equivalents acting with the same physical properties may be substituted therefor.
• waxes, other metal stearates, and heat-meltable gels of other water-soluble polymers having characteristics similar to those of the preferred materials may be substituted because these materials are used for their physical characteristics of antitackiness, temperature melting, film-forming characteristics, and general aptitude for forming a compatible reaction environment for the color reactants.
• the substrate is bond paper of 13 pounds weight per ream of 500 sheets 17 by 22 inches having a medium calendered surface.
• the primer coating for it when dried is one pound per specified ream, and the wet composition is as follows:
• the color-reactant-containing middle coating of 3.25 pounds per specified ream is as follows:
• Percent solids 6-Cl, 8-OCH BIPS 15 Polyvinyl alcohol (98% hydrolyzed) 15 Bis phenol A 65 Calcium stearate water-wettable
• the BIPS type of compound may color slightly prematurely on aging, and this may be prevented by adding to the composition of the coating several percent of the compound 2,4-bis-acetoamido ethane.
• a nominal amount of defoaming and dispersing agents may be used.
• the top coating is 1.75 pounds per specified ream (dry) of the same composition used for the primer coating.
• the essential feature of the invention is the use of powdered nontacky wax in the primer coating and the top coating, and a small percentage of a metal stearate in the middle coating, which contains the color-reactant com ponents, the latter not being restricted to the patricular MP8 or to the acid phenolic material noted in the preferred example but being applicable, for example, where the reactant systems may be selected from among the many disclosed in the Baum United States patent application to which reference has been made.
• Another pair of color reactants useful and representing another type of chromogenic material is crystal violet lactone and Bis phenol A.
• the practitioner of this invention may use the solid powdered nontacky-when-melted wax in any record material coating meant to be melted to cause the bringing together of the color reactants and otherwise having a composition tending to be picked-off by hot type members as they are cooled.
• EXAMPLE II This is the same as Example I except that the primer coating is omitted.
• the heat-sensitive record material of this example performs satisfactorily, but it is not as completely free of film-coating rupture when in contact with the printing head as the material of Example I which has been designated the preferred embodiment.
• a record material including a base sheet having a coating of heat-meltable hydrophilic film-forming material having dispersed in the coating powdered chromogenic material of substantially colorless state and particles of heat-meltable acid phenol compound which when in liquid contact with the chromogenic material reacts therewith to form color

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• Physics & Mathematics (AREA)
• Optics & Photonics (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Heat Sensitive Colour Forming Recording (AREA)

Applications Claiming Priority (1)

Publications (1)

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ID=24004767

Family Applications (1)

Country Status (5)

Cited By (18)

Families Citing this family (2)

Citations (10)

• 1965
  • 1965-10-23 US US3445261D patent/US3445261A/en not_active Expired - Lifetime
• 1966
  • 1966-08-24 GB GB3796466A patent/GB1099880A/en not_active Expired
  • 1966-10-17 CH CH1499366A patent/CH464976A/fr unknown
  • 1966-10-20 DE DE19661571857 patent/DE1571857B2/de active Pending
  • 1966-10-20 SE SE1434466A patent/SE333301B/xx unknown

Patent Citations (10)

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