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
  • B41M5/124—Duplicating or marking methods; Sheet materials for use therein using pressure to make a masked colour visible, e.g. to make a coloured support visible, to create an opaque or transparent pattern, or to form colour by uniting colour-forming components
  • B41M5/132—Chemical colour-forming components; Additives or binders therefor
  • B41M5/155—Colour-developing components, e.g. acidic compounds; Additives or binders therefor; Layers containing such colour-developing components, additives or binders

Definitions

• This invention related to a sheet of paper containing therein a substantially undefined subsident stratum of phenolic polymeric film material. More specifically, this invention relates to manufacturing such a sheet by first printing a solution of the polymeric material onto a paper substrate so that the weight of polymeric material ranges from 0.02 pound per ream (dry basis to 0.6 pound per ream (500 sheets of paper 25 inches by 38 inches or 3,300 square feet) and by a subsequent step of applying a solvent for the phenolic polymeric material to said coated in such a manner that the phenolic coating descends in the paper web along the fibers to a depth below the surface of the paper but not through the paper.
• This subsident phenolic polymeric material clinging to the fibers provides a product having superior chemical reactive properties with a normally colorless chromogenic compound applied thereto as a liquid from the surface, but said liquid before such application being physically and chemically protected.
• the nap-coated sheet of Miller and Bowler is much superior in response to applied liquids, quantitatively, to the continuously-coated product of heavier coating applications. It has, however, the disadvantage of being sensitive to smudge, because the nap fibers are protuberant above the level of the base structure of the paper sheet and thus vulnerable chemically and physically to applied forces and materials. Also, there was an unexpected loss in the intensity of coloration arising from the transfer to the napcoated sheet of the printing liquid transferred from an overlying sheet. It was assumed that 3,466,185 Patented Sept. 9, 1969 some of the applied liquid was lost into the body of the paper below the nap fibers, where there was no phenolic material to act as an acid.
• This invention relates to a process in which the coating on the nap hair of the Miller-Bowler product was subjected to an application of liquid solvent material, which would dissolve the nap hair coating and drive it down into the body of the paper to a determinable distance, depending on the amount of driving-in solvent used.
• the liquid droplets on the transfer side of an over sheet preferably are retained in minute capsules.
• Capsulecoated sheet material for use as a transfer sheet liquid reactant supply to make marks on the novel sheet of this invention is disclosed in Us. Patent No. 2,712,507, which issued July 5, 1955, on the application of Barrett K. Green.
• Earlier, non-capsule, droplet transfer sheets are disclosed in US. Patent No. 2,374,862 which issued May 1, 1945, on the application of Barrett K. Green.
• the originally applied nap-coating solution of the polymeric material should be of water-like consistency and when once applied as a coating and the solvent evaporates should leave a nearly undetectable residue, which, though of small amount and weight with. relation to the paper, is extremely effective because of its architectural relationship as an investment on and between the fibers without substantially aifecting the sheet porosity.
• a mode of use of this invention is to apply the polymeric material solution by rubber printing plates with an intermediate feeder roll and a supply roll dipping into a tank of the solution and thus applying it into a continuous run of paper, which is then passed over a drying station and wound on a receiving roll.
• a dried weight of about 0.02 pound of phenolic resin to 0.6 pound per ream of paper specified is adequate for developing marks in an applied solution of 1.5% by weight, crystal violet lactone, which is a basic colorless compound, dissolved in an inert oil to make up an ink.
• phenolic polymers found useful are paraphenylphenol polymers, paraphenylphenol-formaldehyde polymers, paraalkylphenol-formaldehyde polymers, parahalophenol-formaldehyde polymers, paranitrophenolformaldehyde and alkyl-phenol-acetylene polymers, which are soluble in common organic solvents and possess permanent fusibility in the absence of being treated by crosslinking materials.
• a specific group of useful phenol-aldehyde polymers are members of the type commonly referred to as novolacs (as sold by Union Carbide Corp., New York, NY.) which are characterized by solubility in common organic solvents and which are, in the absence of cross-linking agents, permanently fusible.
• the phenolic polymer material-found useful in practicing this invention is characterized by the presence of free hydroxyl groups and the absence of groups such as methylol, which tend to promote inf usibility or crosslinking of the polymer, and by their solubility in organic solvents and relative insolubility in aqueous media. Again, obviously, mixtures of these phenolic polymers can be employed.
• a laboratory method useful in the selection of suitable phenolic polymeric materials is the determination of the infra-red absorption pattern of a candidate material.
• Solvents for these phenolic materials are ordinary organic solvent materials of relatively great volatility and of low toxicity, among which are the following: normal butanol, ethanol, toluene, xylene, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol diacetate, ethylene glycol dibutyl ether, ethylene glycol dimethyl ether, ethylene glycol monoacetate, ethylene glycol monobenzyl ether, ethylene glycol monobutyl ether (2-butoxyethanol), ethylene glycol monoethyl ether acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monophenyl ether, and ethyl acetate.
• An example of this invention consisted of dissolving 15% by weight of specified phenolic polymeric material in a mixture of 25%, by weight, of ethanol and 75%, by weight, of ethyl acetate.
• the above formulation can be printed onto a paper substrate by means of a Flexographic printer equipped with several printing stations so that the sequential coatings, first with the phenolic material, and then with a solvent mixture to carry the phenolic material into the sheet, can be effected on a single advance of a paper web through the press.
• the second coating (solvent) was composed of equal moieties of ethyl acetate and ethylene glycol monoethyl ether.
• the finished product exhibited an enhanced resistance to smudging when reacted with crystal violet lactone solution to form a colored mark.
• the solvent used in the second coating is not the same as that used as the solvent part of the first coating. This was done to illustrate the freedom of choice as to solvents.
• solvents individually or as mixtures will have different effects as to penetration, solvent power, vaporization, and incompatibility, and with this in mind the practitioner has a wide latitude of choice to achieve the desired results in depth of penetration and porosity thereof with a given fiber structure.
• solvents eligible are ethylene glycol monomethyl ether, ethylene glycol diacetate, ethylene glycol dibutyl ether, ethylene glycol dimethyl ether, ethylene glycol monoacetate, ethylene glycol monomethyl ether acetate, and ethylene glycol monophenyl ether and mixtures of these solvents.
• One mode of applying the second coating is to apply it by rubber printing plates with an intermediate feeder roll and a supply roll dipping into a tank of the solvent, or solvent mixture, onto a continuous run of paper which is then passed over a drying station and wound on a receiving roll.
• Approximately .1 pound to 2 pounds of solvent per ream of paper 25 by 38 inches by 5000 sheets is adequate for practicing the application of the second coating.
• the solvents described above are assigned for use in applying the phenolic material and are not necessarily for use as a solvent vehicle to facilitate reactive contact between color-forming components.
• the liquid solvent must be capable of dissolving both of the mark-forming components.
• the solvent chosen should be capable of dissolving at least 0.3% on a weight basis, of the chromogenic material, and at the same time a corresponding amount of polymeric material to form an etficient reaction.
• the solvent should be capable of dissolving an excess of the polymeric material, so as to provide every opportunity for utilization of all of the chromogenic material present and, thus, to assure the maximum coloration at a reaction site, with the least amount of the expensive chromogenic material.
• the coating liquids that can be used are roller-coating spraying, knife, spreader-bar or blade coating, brushing, or any other mode of application by which controlled amounts can be applied.
• a process of impregnating a sheet of paper with a substituent stratum of phenolic polymeric material to sensitize it with a reactant of acidic properties to develop color in an applied colorless base color reactant comprising (A) printing a solution of organic solvent-soluble phenolic polymeric material onto a face of a paper substrate that when dried leaves a film of the polymeric material in an amount of from 0.02 to 0.6 pound per ream of paper 24 by 36 inches by 500 sheets that festoons the protuberant fibers of said paper sheet,
• step D drying said solvent applied in step C to leave the polymeric material on the fibers within the sheet without occluding the pores.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Color Printing (AREA)
• Duplication Or Marking (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=24502948

Family Applications (1)

Country Status (11)

Cited By (15)

Citations (3)

• 1967
  • 1967-03-21 US US624691A patent/US3466185A/en not_active Expired - Lifetime
• 1968
  • 1968-02-15 GB GB7442/68A patent/GB1179197A/en not_active Expired
  • 1968-03-11 CH CH366568A patent/CH479404A/fr not_active IP Right Cessation
  • 1968-03-16 NO NO1022/68A patent/NO126700B/no unknown
  • 1968-03-19 DK DK115868AA patent/DK122217C/da active
  • 1968-03-19 FR FR1568224D patent/FR1568224A/fr not_active Expired
  • 1968-03-20 SE SE03689/68A patent/SE330482B/xx unknown
  • 1968-03-20 BE BE712451D patent/BE712451A/xx unknown
  • 1968-03-20 AT AT274668A patent/AT282658B/de not_active IP Right Cessation
  • 1968-03-20 ES ES351803A patent/ES351803A1/es not_active Expired
  • 1968-03-21 NL NL6804026A patent/NL6804026A/xx unknown

Patent Citations (3)

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