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
  • B41M5/20—Duplicating or marking methods; Sheet materials for use therein using electric current

Definitions

• My invention relates to a novel electro-sensitive paper which is discolored by the action of an electric current passing through it and, more particularly, relates to a novel dry electrolytic paper for facsimile reception for the production thereon of pictures or printed matter in accordance with the facsimile current received.
• each successive unit area of the paper in turn depends upon uniform thickness of paper at each unit area and the uniformity of the conducting material in the paper.
• This black paper which is now conducting must be provided with a light colored surface which will be discolored in accordance with the electric current, the degree of discoloration being in accordance with the value of the electric current.
• the composition containing the metal should have such a viscosity that it will not to any material degree penetrate into the paper but will form itself substantially as a coating on the outer surface.
• the application of the coating to the black paper be provided by means of a special printing apparatus to be described hereinafter although I may in some cases spray the coating on. In the latter case, however, I have found a tendency for the composition to penetrate the paper.
• the stylus which rides across and carries the current to the recording sheet has a diameter of 10 mils or .01 inch.
• the stylus traces approximately lines per inch and makes approximately 100 current impressions in the paper per inch. Therefore the degree of composition of the powdered metal making up the dry electrolytic paper must be such that unit areas having dimensions of 10 mils in length and width shall have equal conductivity.
• the paper in its original manufacture is mixed with a powdered metal such as carbon or lamp black reduced to as fine a powder as possible and carefully incorporated so as to produce a uniform thickness of paper.
• a powdered metal such as carbon or lamp black
• an electrosensitive coating comprising first a binder base, which may consist of cellulose nitrate or cellulose acetate; secondly, a whiting agent, such as titanium dioxide; thirdly, a metal powder adapted to aid in rendering the coating conductive, this element being for example aluminum powder; and fourth, a thinner adapted to render the coating applicable to the carbon coated paper, which thinner may be alcohol or any suitable solvent for the cellulosic base.
• a binder base which may consist of cellulose nitrate or cellulose acetate
• a whiting agent such as titanium dioxide
• a metal powder adapted to aid in rendering the coating conductive, this element being for example aluminum powder
• a thinner adapted to render the coating applicable to the carbon coated paper, which thinner may be alcohol or any suitable solvent for the cellulosic base.
• I may modify this electro-sensitive coating by adding thereto an agent adapted to accelerate the darkening of the areas which are affected by the electrical impulse.
• an agent adapted to accelerate the darkening of the areas which are affected by the electrical impulse.
• Such an agent enables the coating to be sensitive at a lower voltage and also effects sharper lines of demarcation between the general white appearance of the paper and the black appearance of the area which is subject to the electrical impulse.
• This agent also effects more gradations from the black print to the white coating so that better tone values are obtained in photographs.
• This modifying agent further prevents a so-called bleeding effect and confines the locality of the impulse.
• anilinehydrochloride or its equivalents may also be employed for the same results.
• aniline hydrochloride I may obtain seven grades or tones from pure white to pure black.
• I may further modify my composition by employing therewith a material adapted to cause the coating to flake under the electrical impulse and hence drop from the stylus which transmits the electrical impulse through the coating. Without the employment of such a flaking agent the coating tends to become gummy, to adhere to the stylus moving over the sheet, and thereby impair the action of the stylus.
• a flaking agent I employ potassium nitrate, although equivalent materials may be employed.
• My paper is characterized by the fact that it is of the traditional, and therefore satisfactory, white appearance. It further is characterized by an extremely desirable sensitivity to such electrical impulses to which it is subjected to facsimile reception. My paper is further non-toxic, inexpensive to manufacture and capable of uniform results.
• I flrst manufacture my conductive paper by impregnating the pulp with as much lamp black as it will hold without falling apart. The final paper comes out about .003 of an inch thick. This paper is now coated with a conducting layer whose thickness is controlled to about .00025 of an inch. Although, as will appear from the following, the coating will contain non-conductive ingredients, these may be controlled to the coating itself controlled.
• the coating compositions are:
• the titanium dioxide is mixed with the binder and suflicient aluminum powder is added so that the coating is rendered conductive but without turning the coating grayish or too dark.
• the mix so formed is thinned out with the thinner and the solution is then applied to a carbon impregnated paper by any of the well known methods of spraying, flowing, dipping or the like.
• a Benday roll This roll has a surface engraved like a screen. Coating in this way gives a very uniform and thin coating which has been found pre-eminently desirable.
• the titanium dioxide is mixed with the cellulosic binder and the aluminum powder is added to that mix.
• the coating After the coating has been properly dried upon the carbon impregnated paper it may be employed for facsimile reception as described above.
• the electrical impulse transmitted by the stylus which contacts the coating through to the conductive carbon impregnated paper causes the coating (A or B) to turn black.
• the aniline compound is heat sensitive and turns brown upon being heated. This tends to accelerate the formation of the black print.
• the cellulosic binder is given by way of example only. Any suitable binding material may be employed and for that purpose many plastic materials including cellulosic compounds and resins, natural or synthetic, and gums may be employed. Certain binders, such as casein, are mechanically suitable, but because of the smell engendered by the heat conversion due to the electrical impulse, it has been found undesirable.
• Totanium dioxide is very suitable as a whiting agent, but other agents adapted to provide the white effect may be employed. Zinc oxide, lead oxide and lead carbonate are typical of such whiting agents. I may also employ the sulphides which work fairly well. They appear not to be sensitive enough and hence I prefer to employ the titanium dioxide referred to above.
• the aluminum powrier is a suitable agent for enhancing the conductance of the coating. At the same time the aluminum when used in proper quantities does not deleteriously darken the coating. However, any suitable metal powder or metal salt that effects this result of enhancing the conductivity of the coating may be employed. Nickel chloride, for example, has been found effective.
• aniline hydrochloride The functions of the aniline hydrochloride have been defined above. Summarizing, it adds to the sensitivity of the titanium dioxide and causes it to turn black under lower temperatures and it, therefore, enables lower voltages to be employed inv the facsimile receiver.
• the aluminum hydrochloride further effects a better detail in that it causes sharper lines of demarcation between the black areas and the white areas and hence more gradations from black to white. Therefore, in photographs it produces desirable tone values which give half tone effects and gradations of color in pictures. It sharply confines the area converted in color and prevents bleeding effects. I have found that I can obtain seven grades of color from pure white to pure black.
• aniline hydrochloride or its equivalents are a material aid in sharpening the image. I have found that cadmium iodide may be substituted for the aniline hydrochloride to good effect.
• the potassium nitrate acts to cause the converted coating to become flaky. It is my belief that this is effected because the oxygen released from the potassium nitrate aids in the complete oxidation of the carbon compound, the aniline hydrochloride, and therefore gives a flaky residue instead of a gummy compound. Certain other nitrates also act to aid in the complete combustion, that is providing the necessary oxygen. I have found that sodium nitrate may be used to good effect. The nitrate is, therefore, a good combustion agent.
• the coating is of such viscosity that it flows to join the adjacent globule and thus an even coating is formed.
• the viscosity of the solution preferably is about 3.2 poises.
• my method of application comprises picking up on a number of separated relatively small surfaces a coating of such viscosity that upon application of .that coating to a material, such as paper, each globule of coating will flow sufficiently to join the adjacent globule to form a coating of uniform thickness.
• the coating method I has set forth above is particularly applicable for the problem presented in paper for facsimile recording. It is of fundamental importance that that coating be of the greatest possible uniformity and that there be no high spots that would act to interfere with the current transfer or with the stylus traversing the coating. This process of coating, therefore, is peculiar to facsimile recording paper.
• a dry electrolytic facsimile recording paper for discoloring upon the passage of electric currents therethrough comprising a comparatively dark conductive paper sheet, said sheet being uniformly coated with a comparatively light electrosensitive coating, said coating comprising a mixture of titanium dioxide, a conductive metallic powder, aniline hydrochloride, and potassium nitrate.
• a dry electrolytic facsimile recording paper for discoloring upon the passage of electric currents therethrough comprising a comparatively dark conductive paper sheet, said sheet being uniformly coated with a comparatively light electrosensitive coating, said coating comprising a dried homogeneous mixture of titanium dioxide, a metallic powder, aniline hydrochloride, potassium nitrate, and a dilute solution of a cellulosic binder.

Landscapes

• Paper (AREA)
• Time Recorders, Dirve Recorders, Access Control (AREA)
• Photoreceptors In Electrophotography (AREA)

Priority Applications (5)

Applications Claiming Priority (1)

Publications (1)

Family

ID=23015679

Family Applications (1)

Country Status (5)

Cited By (12)

Families Citing this family (1)

• 0
  • BE BE438609D patent/BE438609A/xx unknown
• 1939
  • 1939-04-07 US US266709A patent/US2310946A/en not_active Expired - Lifetime
• 1940
  • 1940-04-06 FR FR864689D patent/FR864689A/fr not_active Expired
  • 1940-04-08 GB GB6325/40A patent/GB536395A/en not_active Expired
  • 1940-10-17 CH CH263296D patent/CH263296A/fr unknown

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