US3900215A - Record sheet - Google Patents

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Publication number
US3900215A
US3900215A US325720A US32572073A US3900215A US 3900215 A US3900215 A US 3900215A US 325720 A US325720 A US 325720A US 32572073 A US32572073 A US 32572073A US 3900215 A US3900215 A US 3900215A
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US
United States
Prior art keywords
record sheet
acid
metal
aromatic carboxylic
carboxylic acid
Prior art date
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
US325720A
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English (en)
Inventor
Hajime Kato
Takao Hayashi
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.)
Fujifilm Holdings Corp
Original Assignee
Fuji Photo Film Co Ltd
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.)
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Publication date
Application filed by Fuji Photo Film Co Ltd filed Critical Fuji Photo Film Co Ltd
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Publication of US3900215A publication Critical patent/US3900215A/en
Anticipated expiration legal-status Critical
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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

  • ABSTRACT A record sheet comprising a base sheet and coated thereon a layer of a developer which produces a colored image upon reaction with a color former such as crystal violet lactone, said developer comprising (1) a metal compound of an aromatic carboxylic acid such as a reaction product of 2-hydroxy-l-naphthoic acid and zinc chloride and (2) a metal salt such as copper sulfate or nickel sulfate.
  • a color former such as crystal violet lactone
  • Color forrners can also be defined as electron-donating or proton-accepting colorless chromogenic materials and generally they are organic solvent-soluble, basic, substantially colorless organic compounds such as diarylmethane compounds, triarylmethane compounds, fluorane compounds, spiropyrane compounds and leucoazine compounds.
  • Such record sheets include pressure-sensitive copying papers as are described, for example, in US. Pats. Nos. 2,505,470, 2,505,489, 2,550,471, 2,548,366, 2,712,507, 2,730,456, 2,730,457, and 3,418,250 and thermosensitive record papers as described, for example, in Japanese Patent Publication No. 4160/68 and US. Pat. No. 2,939,009.
  • a printing method is known which comprises supplying ink containing a color former to a sheet coated with a developer through a medium such as a stencil to thereby obtain a colored image, e.g., see German OLS No. 1,939,624.
  • the color reaction which takes place between the color former and the developer requires pressure applied by a pen or typewriter, heat or ,some other altered physical condition.
  • Pressuresensitive copying papers can be obtained by dissolving a color former in a solvent such as chlorinated diphenyl or chlorinated paraffin, dispersing the solution in a hinder or incorporating it into microcapsules, and then coating the dispersion or the microcapsular'solution obtained on a base material such as paper, a plastic film or a resin-coated paper.
  • a solvent such as chlorinated diphenyl or chlorinated paraffin
  • thermosensitive recording paper can be obtained by coating a color former and a thermofusible substance such as acetanilide on a base sheet.
  • the thermofusible substance melts upon the application of heat and dissolves the color former.
  • the developer is usually dissolved or dispersed in water or an organic solvent along with a binder, and then coated on, or impregnated in, the base material. It can also be coated or impregnated as an ink just prior to recording.
  • the color former and developer are applied to the same or opposite surfaces of a base material, or to separate base materials.
  • Examples of the known developers are clays such as acid clay, activated clay, attapulgite, zeolite, or bentonite, organic acids such as succinic acid, tannic acid, gallic acid or phenolic compounds, and acid polymers such as phenol resins.
  • the phenol resins have attracted attention as new developers (Japanese Patent Publication No. 20144/67), and a number of improved phenol resin developers have been proposed (U.S. Pats. Nos. 3,516,845 and 3,540,911 and British Patent 1,065,587).
  • the phenol resins are superior to many other developers in that when reacted with a color former they form a colored image stable to water, but they have the defect of insufficient color developing ability and give colored images which are poor in light resistance.
  • a colored image obtained by reaction of a phenol resin with crystal violet lactone readily fades when it is allowed to stand indoors or it is exposed to sunlight, and the surface of the phenol resin which has not participated in color production turns yellow.
  • the inventors of the present invention previously suggested the effectiveness of metal compounds of aromatic carboxylic acids as developers for use in preparing record sheets.
  • Various properties of the developer were thus substantially improved by using the metal compounds of aromatic carboxylic acids.
  • the light resistance of a color image resulting from crystal violet lactone as a color former is improved, but the extent of improvement is inferior to that attained with benzoyl leuco methylene blue.
  • one object of this invention is to increase the color developing ability of a metal' compound of an aromatic carboxylic acid.
  • a second object of this invention is to increase the light resistance of a colored image obtained using a metal compound of an aromatic carboxylic acid
  • a third object of this invention is to provide a developer which meets the above objects.
  • Another object of this invention is to provide'a record sheet which meets the above objects.
  • the record sheet of this invention basically comprises a base with a layer containing a metal compound of an aromatic carboxylic acid and a metal salt coated on the base material, and therefore can be in any form known in the art.
  • the developer and the color former may be applied to the same or opposite surfaces of the base, or to separate base sheets. It is also possible to store the developer in the form of ink, and
  • aromatic carboxylic acids are, for example, zinc, tin, aluminum, nickel, magnesium and calcium salts of aromatic carboxylic acids, which are most preferred materials for use in the present invention.
  • aromatic carboxylic acids include benzoic acid, o-, mand pchlorobenzoic acids, o, mand p-nitrobenzoic acids, mand p-toluic acids, 4-metyl-3-nitrobenzoic acid, 2-chloro-4-nitrobenzoic acid, 2,3-dichlorobenzoic acid, 2,4-dichlorobenzoic acid, p-isopropylbenzoic acid, 2,5-dinitrobenzoic acid, p-tert.-butyl-benzoic acid, N-phenylanthranilic acid, 4-metyl-3-nitrobenzoic acid, salicylic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, 3,5dinitrosalicy
  • aromatic carboxylic acids having at least one hydroxyl group at one orthoposition to the carboxyl group prove effective, though both ortho positions can be substituted.
  • aromatic carboxylic acids having at least one hydroxyl group at one orthoposition to the carboxyl group
  • no more than two hydroxyl groups will be used as increasing numbers have a tendancy to lower water resistance.
  • those acids which have an electronattracting group such as a halogen atom, an alkoxycarbonyl, an alkylcarbonyl group and like electron-attracting groups.
  • the aromatic ring of the aromatic carboxylic acid is preferably a benzene or naphthalene ring because as the number of rings increases the acids begin to become slightly colored. Further, the aromatic carboxylic acid preferably is substituted with an alkyl group because such a group advantageously solublizes the acid in an oily solution of color former. In this case, as the number of alkyl groups increases, synthesis of the acids becomes more complicated, and so the number of alkyl group is preferably no more than two for ease of synthesis.
  • a substituent introduced into an aromatic ring is a hydrocarbon group such as an alkyl, aralkyl or aryl group
  • the number of carbon atoms thereof is preferably no more than 12 because the compound will gradually show weakened solubility in an aqueous alkali solution in the preparation of the metal salt thereof.
  • metals which constitute the metal compounds of aromatic carboxylic acids used in this invention are the metals of Group IB of the periodic table e.g., copper or silver, metals of Group IIA, e.g., magnesium and calcium, metals of Group IIB, e.g., zine, cadmium or mercury, metals of Group IIIA, e.g., aluminum or potassium, metals of Group IVA, e.g., tin or lead, metals of Group VIB, e.g., chromium or molybdenum, metals of Group VIIB, e.g., manganese, and metals of 4 Group VIII, e.g., cobalt or nickel. Ofthese, zinc and tin are especially effective.
  • metals of Group IB of the periodic table e.g., copper or silver
  • metals of Group IIA e.g., magnesium and calcium
  • metals of Group IIB e.g., zine, cadmium or mercury
  • the metal salt to be jointly used with the above described metal compound can be an inorganic or organic metal salt such as a salt formed between a metal and an inorganic acid such as sulfuric acid, hydrochloric acid, nitric acid or phosphoric acid, and a salt formed between a metal and an aliphatic organic acid such as acetic acid, citric acid, formic acid or oxalic acid.
  • an inorganic or organic metal salt such as a salt formed between a metal and an inorganic acid such as sulfuric acid, hydrochloric acid, nitric acid or phosphoric acid
  • a salt formed between a metal and an aliphatic organic acid such as acetic acid, citric acid, formic acid or oxalic acid.
  • the inorganic salts such as inorganic acid salts give especially good results.
  • Additional examples of useful inorganic metal salts are the metal bromides, metal cyanides, metal iodides and metal sulfates.
  • metals that form the metal salt examples include copper, aluminum, manganese, nickel, silver, cobalt, and iron, and copper and nickel are especially preferred. Therefore, copper salts of inorganic acids and nickel salts of inorganic acids are the most preferred examples of metal salts used in this invention.
  • the action of the salt between a metal and either an inorganic acid or aliphatic acid depends primarily on the metal and not on the inorganic or aliphatic acid used, so the acid selected is not limited. However, as the molecular weight of the aliphatic organic acid increases, the results become lessened because the amount of metal in the salt is lessened. Accordingly, one will generally use the lower molecular weight aliphatic inorganic acids as exemplified above.
  • the developer layer may contain an acidic resin such as a phenol-formaldehyde resin, an inorganic pigment such as a metal oxide, metal hydroxide or clay, or a chemically or physically treated produet thereof without appreciably impairing the advantages of this invention.
  • the amount of these materials is generally 0.1 to 10 parts by weight based on 1 part by weight of aromatic acid.
  • Specific examples of such ma terials are zinc oxide, titanium oxide, zinc hydroxide, zinc carbonate, acid clay, active clay, attapulgite, kaolin, etc.
  • Other additives which increase the color developability are an adsorbent substance which has no color developing property in itself, such as agolmatolite or tale.
  • the amounts which generally will be used are the same as those for the acidic resin above.
  • a coating solution of the developer according to this invention can be prepared by dissolving or dispersing at least one metal compound of an aromatic carboxylic acid and at least one metal salt in a solvent.
  • a binder such as a latex, polyvinyl alcohol, a maleic anhydride/styrene copolymer, starch or gum arabic, and
  • an ordinary developer such as acid clay or activated clay may be added in order to increase the developing ability
  • an inorganic pigment may also be added in order to increase the adsorbing property of the developer.
  • Other additives which increase the color developability are an adsorbent substance which has no color developing property in itself, such as agolmatolite or talc. The amounts which generally will be used are the same as those for the acidic resin above.
  • the coating solution obtained is coated on a base material such as paper, synthetic paper-like sheet or film in an amount such that it picks up at least about 0.1 g/m preferably from 0.5 to about 2 g/m of the metal compound of an aromatic carboxylic acid.
  • the upper limit of the amount of coating is determined mainly by economic reasons, and therefore, greater amounts than the above-specified limit will not have any harm on the effects of this invention.
  • the amount of the binder to be used is preferably from 5 to 20 parts by weight based on 100 parts by weight of the metal compound of an aromatic carbox ylic acid.
  • the minimum value of the binder is decided by the strength of the color developer layer. The maximum value thereof is decided by the color density desired.
  • the amount of the metal salt used is at least 0.1 part by weight, preferably from 0.5 to parts by weight, based on 100 parts by weight of the metal compound of an aromatic carboxylic acid.
  • the record sheet of this invention is characterized by a specific developer, other conditions such as the type of additives to be incorporated in the developer, the type and form of the color former, or the type of the solvent, are in accordance with the prior art heretofore described and can be easily chosen by those skilled in the art.
  • the light resistance of colored images is greatly increased and the developing ability of the developer is markedly improved.
  • the developer of the present invention is especially effective when used with a combination of a primary color former having the ability to yield color instantaneously and a secondary color former having superior light resistance, as disclosed in U.S. Pat. No. 3,427,180.
  • Microcapsules containing a color former can be prepared by various methods. ln the following Examples, however, they were prepared by the specific method set out in the specification of U.S. Pat. No. 2,800,457 which is described below. Other encapsulation techniques which can be used are described in the following U.S. Patents: Nos. 2,800,458, 3,041,289, 3,116,206, 3,173,878, 3,190,837 or 3,265,630.
  • a record sheet coated with microcapsules containing benzoyl leuco methylene blue was prepared in the same manner.
  • EXAMPLE 1 One gram equivalent of each aromatic carboxylic acid indicated in Table l was dissolved in 2 liters of a 2% aqueous solution of sodium hydroxide. Separately, one gram equivalent of each metal salt indicated in Table l was dissolved in 250 ml of warm water. The aqueous metal salt solution was poured with stirring into the aqueous sodium hydroxide solution of the aromatic carboxylic acid. Immediately, a metal compound of the aromatic carboxylic acid precipitated. The precipitate was filtered, washed several times with water, and dried to obtain a metal compound of the aromatic carboxylic acid.
  • each binder indicated in Table l Ten grams of each binder indicated in Table l was dissolved in 400 ml of each solvent indicated in Table 1, and g of the metal compound of the aromatic carboxylic acid obtained above and 2 g of each metal salt indicated in Table l which passed through a sieve with 325 mesh or smaller were dissolved or dispersed in the binder solution.
  • the coating solution obtained was coated on a base paper having a unit weight of 50 g/m in an amount of 2 g/m as solids content using a coating rod, and dried.
  • EXAMPLE 2 0.1 g equivalent of each aromatic carboxylic acid indicated in Table l was dissolved in 200 ml of a 2% aqueous solution of sodium hydroxide by heating, and 100 g of a 10% aqueous solution of polyvinyl alcohol were added tothe resultant solution.
  • COMPARATIVE EXAMPLE 1 10 g of ethyl cellulose was dissolved in 400 ml of ethanol, and in this binder solution were dissolved or dispersed 100 g of the metal compound of the aromatic carboxylic acid obtained in Example 1. The resulting coating solution was coated on a base paper having a unit weight of 50 g/m in an amount of 2 g/m as solids content using a coating rod, and dried.
  • COMPARATIVE EXAMPLE 2 The dispersion of the metal compound of the aro matic carboxylic acid prior to the addition of the metal salt in Example 2 was used as a coating solution, and coated on a base paper having a unit weight of 50 g/m in an amount of 3 g/m as solids content using a coating rod, followed by drying.
  • the sheets were allowed to stand one day and one night in a dark place, and the reflection spectrum at a wavelength between 380 my. and 700 my. was measured by a Beckman spectrophotometer (Model DB).
  • the absorbance at the absorption maximum was made the fresh density of the developed color.
  • the developed color was exposed to sunlight for 2 hours, and the reflection spectrum of the color surface was measured to 5 determine the density.
  • Com 1 5 Salicylic aluminum 0.97 0.65 0.25 0.48
  • Com. 2 16 Z-hydroxyaluminum 0.91 0.65 0.25 0.49
  • a record sheet comprising a base sheet and coated thereon a layer of a developer which produces a colored image upon contact with an electron-donating colorless chromogenic material, said developer comprising l) a metal compound of an aromatic carboxylic acid and (2) from 0.5 to 10 parts by weight per 100 parts by weight of the metal compound l) of a salt of a metal.
  • aromatic carboxylic acid constituting the metal compound (1 is selected from the group consisting of benzoic acid, benzoic acid derivatives, salicylic acid, salicylic acid derivatives, naphthoic acids, anacardic acid, toluic acids and Z-carboxybenzaldehyde.
  • aromatic carboxylic acid constituting the metal compound (1) is an aromatic carboxylic acid containing at least one hydroxyl group.
  • metal of said metal compound (1) is selected from metals of Groups IB, IIA, IIB, IIIA, IVA, VIB, V118 and VIII of the periodic table.
  • the record sheet of claim 8 wherein the metal is selected from the group consisting of copper, silver, magnesium, calcium, zinc, cadmium, mercury, aluminum, potassium, tin, lead, chromium, molybdenum, manganese, cobalt and nickel.
  • the record sheet of claim 2, wherein the metal of said salt (2) is selected from the group consisting of copper, aluminum, manganese, nickel, silver, cobalt, and iron.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Color Printing (AREA)
  • Heat Sensitive Colour Forming Recording (AREA)
US325720A 1972-01-24 1973-01-22 Record sheet Expired - Lifetime US3900215A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP47008830A JPS5229205B2 (enrdf_load_stackoverflow) 1972-01-24 1972-01-24

Publications (1)

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US3900215A true US3900215A (en) 1975-08-19

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US (1) US3900215A (enrdf_load_stackoverflow)
JP (1) JPS5229205B2 (enrdf_load_stackoverflow)
BE (1) BE794459A (enrdf_load_stackoverflow)
DE (1) DE2303405C2 (enrdf_load_stackoverflow)
ES (1) ES410879A1 (enrdf_load_stackoverflow)
GB (1) GB1426641A (enrdf_load_stackoverflow)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4186243A (en) * 1976-02-25 1980-01-29 Ciba-Geigy Corporation Image producing system
US4239815A (en) * 1977-12-07 1980-12-16 Fuji Photo Film Co., Ltd. Method of producing recording sheets
US4269893A (en) * 1978-05-12 1981-05-26 Fuji Photo Film Co., Ltd. Recording material containing a novel color developer
US4407886A (en) * 1980-11-24 1983-10-04 Basf Aktiengesellschaft Pressure-sensitive and heat-sensitive recording material
US4828957A (en) * 1986-05-31 1989-05-09 Kanzaki Paper Manufacturing Company, Ltd. Two-color heat-sensitive recording material with 2-hydroxy-3-naphthoanilide as both coupler and color developing agent
US5037797A (en) * 1988-07-18 1991-08-06 Kanzaki Paper Manufacturing Company, Limited Acceptor coated sheet for pressure-sensitive copying system
US5393332A (en) * 1991-12-27 1995-02-28 Sanko Kaihatsu Kagaku Kenkyusho Color developer for pressure-sensitive recording sheets
US7265077B1 (en) 2005-02-10 2007-09-04 Netsch Bryan A Latent image developing systems and devices
US20070207416A1 (en) * 2006-03-03 2007-09-06 Netsch Bryan A Latent image systems, developers, and blockers therefor

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI781627A7 (fi) * 1977-05-28 1978-11-29 Ciba Geigy Ag Vaermekaensligt upptecknings- eller kopieringsmaterial
US4188456A (en) 1977-12-23 1980-02-12 Ncr Corporation Pressure-sensitive recording sheet
JPS5510705U (enrdf_load_stackoverflow) * 1978-07-05 1980-01-23
AT372909B (de) 1979-03-20 1983-11-25 Manuel Ing Cespon Farbentwicklermassen zur herstellung eines druck- empfindlichen aufzeichungsmaterials mit besonders starker farbbildung und lichtbestaendigkeit
EP2919998B1 (en) 2012-11-14 2019-12-25 Active Device Development Limited Colour-forming materials

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2505471A (en) * 1944-01-31 1950-04-25 Ncr Co Process of making pressure sensitive record material
US2939009A (en) * 1956-02-01 1960-05-31 Jack M Tien Thermotransfer duplicating process
US3418250A (en) * 1965-10-23 1968-12-24 Us Plywood Champ Papers Inc Microcapsules, process for their formation and transfer sheet record material coated therewith
US3558341A (en) * 1968-04-01 1971-01-26 Ncr Co Pressure-sensitive record material
US3664858A (en) * 1970-02-18 1972-05-23 Minnesota Mining & Mfg Heat-sensitive copy-sheet
US3689302A (en) * 1970-01-09 1972-09-05 Ricoh Kk Thermographically color-developable composition
US3767449A (en) * 1970-09-28 1973-10-23 Fuji Photo Film Co Ltd Recording sheet
US3769302A (en) * 1969-01-21 1973-10-30 T Hoover Aliphatic amino-substituted flourans

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1323937A (en) * 1969-09-26 1973-07-18 Fuji Photo Film Co Ltd Developer sheets for pressure-sensitive recording paper

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2505471A (en) * 1944-01-31 1950-04-25 Ncr Co Process of making pressure sensitive record material
US2939009A (en) * 1956-02-01 1960-05-31 Jack M Tien Thermotransfer duplicating process
US3418250A (en) * 1965-10-23 1968-12-24 Us Plywood Champ Papers Inc Microcapsules, process for their formation and transfer sheet record material coated therewith
US3558341A (en) * 1968-04-01 1971-01-26 Ncr Co Pressure-sensitive record material
US3769302A (en) * 1969-01-21 1973-10-30 T Hoover Aliphatic amino-substituted flourans
US3689302A (en) * 1970-01-09 1972-09-05 Ricoh Kk Thermographically color-developable composition
US3664858A (en) * 1970-02-18 1972-05-23 Minnesota Mining & Mfg Heat-sensitive copy-sheet
US3767449A (en) * 1970-09-28 1973-10-23 Fuji Photo Film Co Ltd Recording sheet
US3772052A (en) * 1970-09-28 1973-11-13 Fuji Photo Film Co Ltd Recording sheet and color developer therefor

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4186243A (en) * 1976-02-25 1980-01-29 Ciba-Geigy Corporation Image producing system
US4239815A (en) * 1977-12-07 1980-12-16 Fuji Photo Film Co., Ltd. Method of producing recording sheets
US4269893A (en) * 1978-05-12 1981-05-26 Fuji Photo Film Co., Ltd. Recording material containing a novel color developer
US4407886A (en) * 1980-11-24 1983-10-04 Basf Aktiengesellschaft Pressure-sensitive and heat-sensitive recording material
US4828957A (en) * 1986-05-31 1989-05-09 Kanzaki Paper Manufacturing Company, Ltd. Two-color heat-sensitive recording material with 2-hydroxy-3-naphthoanilide as both coupler and color developing agent
US5037797A (en) * 1988-07-18 1991-08-06 Kanzaki Paper Manufacturing Company, Limited Acceptor coated sheet for pressure-sensitive copying system
US5393332A (en) * 1991-12-27 1995-02-28 Sanko Kaihatsu Kagaku Kenkyusho Color developer for pressure-sensitive recording sheets
US7265077B1 (en) 2005-02-10 2007-09-04 Netsch Bryan A Latent image developing systems and devices
US20070207416A1 (en) * 2006-03-03 2007-09-06 Netsch Bryan A Latent image systems, developers, and blockers therefor
US7858555B2 (en) 2006-03-03 2010-12-28 Netsch Bryan A Latent image systems, developers, and blockers therefor

Also Published As

Publication number Publication date
GB1426641A (en) 1976-03-03
DE2303405C2 (de) 1982-03-18
JPS4879019A (enrdf_load_stackoverflow) 1973-10-23
JPS5229205B2 (enrdf_load_stackoverflow) 1977-08-01
DE2303405A1 (de) 1973-08-02
ES410879A1 (es) 1975-12-01
BE794459A (fr) 1973-05-16

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