EP0478263A1 - Wärmeempfindliches Aufzeichnungsmaterial - Google Patents

Wärmeempfindliches Aufzeichnungsmaterial Download PDF

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Publication number
EP0478263A1
EP0478263A1 EP91308649A EP91308649A EP0478263A1 EP 0478263 A1 EP0478263 A1 EP 0478263A1 EP 91308649 A EP91308649 A EP 91308649A EP 91308649 A EP91308649 A EP 91308649A EP 0478263 A1 EP0478263 A1 EP 0478263A1
Authority
EP
European Patent Office
Prior art keywords
heat
sensitive recording
layer
recording material
recording layer
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.)
Granted
Application number
EP91308649A
Other languages
English (en)
French (fr)
Other versions
EP0478263B1 (de
Inventor
Syuji Yoda
Yoshihiro Shimizu
Katsuaki Yoshizawa
Hisayoshi Mito
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.)
Kanzaki Paper Manufacturing Co Ltd
Original Assignee
Kanzaki Paper Manufacturing 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.)
Filing date
Publication date
Application filed by Kanzaki Paper Manufacturing Co Ltd filed Critical Kanzaki Paper Manufacturing Co Ltd
Publication of EP0478263A1 publication Critical patent/EP0478263A1/de
Application granted granted Critical
Publication of EP0478263B1 publication Critical patent/EP0478263B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • B41M5/26—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

Definitions

  • the present invention relates to a heat-sensitive, recording material and particularly to a heat-sensitive recording material superior in retainability of the recorded images.
  • heat-sensitive recording materials utilizing the colorforming reaction between a colorless or pale colored basic chromogenic material and an organic or inorganic color developer, in which the two colorforming materials are thermally contacted each other to produce recorded images.
  • These heat-sensitive recording materials are relatively low in price and the recording equipments are compact and can be easily maintained. Therefore, they have been used not only as the recording medium of facsimiles, various computers and like, but also in the other various fields.
  • the application as a label has been increased with the enlargement of the POS (point of sales) systematization in retail stores and the like.
  • the label contacts with water, lapping films and oils in many cases and as the result the recorded image (printed letters) on the heat-sensitive label is discolored disadvantageously.
  • the heat-sensitive recording material it is required for the heat-sensitive recording material to have good retainability of the recorded images, such as water-resistance, plasticizer-resistance and oil-resistance and the like.
  • a heat-sensitive recording material has on a base sheet a coating layer comprising a colorless or pale colored basic chromogenic material and a color developer which develops a color by contacting with the chromogenic material.
  • the coating layer comprises 2,4′dihydroxydiphenyl sulfone as the color developer, and further comprises at least one epoxy resin represented by the following formula (I) or (II): where each of R1 and R2 is one of the groups represented by the following formulae 1 to 8, -COOH 1 and l is 0 or an integer of 1 to 5 and m, n, p, q, r, s, t and u are respectively an integer of 1 to 5, but at least one of R1 and R2 is not -COOH, and R3 is one of the groups represented by the above formulae 2 to 8.
  • the coating layer may be either a single layer of a heat-sensitive recording layer comrising the chromogenic material and the color developer, or multiple layers comprising the heat-sensitive recording layer and a protective layer.
  • the epoxy resin may be comprised either in the heat-sensitive recording layer or the protective layer.
  • the heat-sensitive recording material according to the present invention uses selectively 2,4′-dihydroxydiphenyl sulfone as a color developer to constitute the recording layer as mentioned above and also uses an epoxy resin represented by the above formula (I) or (II) in combination with the specific color developer to attain the expected purpose.
  • the epoxy resin used in the present invention can be contained in the protective layer of the heat-sensitive recording material, satisfactory effect cannot necessarily attained. Hence, it is preferred to be contained in the recording layer.
  • the epoxy resin is contained in the recording layer, the retainability of the recorded image is remarkably improved with no lowering of whiteness of the recording layer. Further, an additional effect of improvement in recording sensitivity can be also attained.
  • Typical examples of the epoxy resins represented by the above formula (I) include, for example, 1,4-di(1,2-epoxyethyl)benzene, 1,4-diglycidyl benzene, 1,4-di(2-glycidyloxy)benzene, 1,4-di(2-glycidyloxyethoxy)benzene, 1,4-di(4-glycidyloxybutoxy) benzene, 1,3-di(glycidyloxy)benzene, 1,2-di(glycidyloxy)benzene, 1, 4-diglycidyl phthalate, 1,4-di(2-glycidyloxyethyl) phthalate, monoglycidyl phthalate and the like.
  • the epoxy resins represented by the formula (I) in which R1 is identical with R2 are preferred.
  • Typical examples of the epoxy resins represented by the formula (II) include, for example, glycidyloxybenzene, 1-phenoxy-14-glycidyloxy-3,6,9,12-tetraoxatetradecane and the like.
  • 1,4-di(glycidyloxy)benzene and 1,4-diglycidyl phthalate are used most preferably as they are excellent in plasticizer-resistance and shows low formation of fogging.
  • the amount of the epoxy resin used is not especially restricted but it is generally used in the range of 0.1 to 500 parts by weight, preferably 1 to 200 parts by weight based on 100 parts by weight of the color developer.
  • 2,4′-dihydroxydiphenyl sulfone is essentially used as the color developer, but the other color developers may be used together with it in such an amount as the advantages of the present invention is not inhibited.
  • inorganic acidic compounds such as activated clay, attapulgite, colloidal silica, aluminum silicate and the like
  • organic acidic compounds such as phenolic compounds, e.g., 4-tert-butylphenol, 4-hydroxydiphenoxide, ⁇ -naphthol, ⁇ -naphthol, 4-hydroxyacetophenol, 4-tert-octylcatechol, 2,2′-dihydroxydiphenol, 4,4′-iso-propylidenebis(2-tert-butylphenol), 4,4′-sec-butylidenediphenol, 4-phenylphenol, 4,4′-isopropylidenediphenol, 2,2-bis(4-hydroxyphenyl)-4-methylpentane, 2,2′-methylenebis(4-chlorophenol), hydroquinone, 4,4′-cyclohexylidenediphenol, 4,4′
  • various known colorless or pale colored basic chromogenic materials can be exemplified. They include triallyl methane chromogenic materials such as 3,3-bis(p-di methylaminophenyl)-6-dimethylaminophthalide, 3,3-bis(p-dimethylaminophenyl)phthalide, 3-(p-dimethylaminophenyl)-3-(1,2-dimethylindol-3-yl)phthalide, 3-(p-dimethylaminophenyl)-3-(2-methylindol-3-yl)phthalide, 3,3-bis(1,2-dimethylindol-3-yl)-5-dimethylaminophthalide, 3,3-bis(J,2-dimethylindol-3-yl)-6-dimethylaminophthalide, 3,3-bis(9-ethylcarbazol-3-yl)-6-dimethylaminophthalide,
  • the ratio of the basic chromogenic material to the above specific color developer may be adjusted appropriately in accordance with the type of the basic chromogenic material.
  • the color developer is used in an amount of 0.1 to 50 parts by weight, preferably 1 to 10 parts by weight, based on 1 part by weight of the basic chromogenic material.
  • the coating composition for heat-sensitive recording layer containing these substances is prepared in general by dispersing them in water as the dispersion medium by using a stirring pulverizer such as a ball mill and a sand mill.
  • Typical binders include, for example, starches, hydroxyethyl cellulose, methyl cellulose, carboxymethyl cellulose, gelatin, casein, gum arabic, polyvinyl alcohol, acetoacetyl-modified polyvinyl alcohol, carboxyl-modified polyvinyl alcohol, silicon-modified polyvinyl alcohol, diisobutylene-maleic anhydride copolymer salt, styrene-maleic anhydride copolymer salt, ethylene-acrylic acid copolymer salt, styrene-acrylic acid copolymer salt, styrene-butadiene copolymer emulsion, urea resin, melamine resin and amide resin.
  • additives such as dispering agents, e.g.,sodium dioctylsulfosuccinate, sodium dodecylbenzene sulfonate, sodium lauryl sulfate, a metal salt of a fatty acid and the like, ultraviolet absorbers; e.g., benzophenone compounds and the like; defoaming agents; fluorescent dyes; coloring dyes; waxes e.g., zinc stearate, calcium stearate, polyethylene wax, carnauba wax, paraffin wax, ester wax and the like; inorganic pigments, e.g., kaolin, clay, talc, calcium carbonate, calcined kaolin, titanium oxide, diatomaceous earth, fine particle anhydrous silica, activated clay and the like.
  • a sensitizer may be used simultaneously.
  • Typical examples of the sensitizers include such as fatty amides, e.g., stearic amide, stearic methylenebisamide, oleic amide, palmitic amide and coconut fatty amide; hindered phenols, e.g., 2,2′-methylenebis(4-methyl-6-tert-butylphenol), 4,4′-butylidenebis(6-tert-butyl-3-methylphenol), 2,2′-methylenebis(4-ethyl-6-tert-butylphenol), 2,4-di-tert-butyl-3-methylphenol, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,1,3-tris(5-cyclohexyl-4-hydroxy-2-methylphenyl)butane and 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate; ultraviolet ray
  • 1,2-di(3-methylphenoxy)ethane, 1, 2-diphenoxyethane and 1-(2-ethylphenoxy)-2-(4-methoxyphenoxy) ethane are preferably used among these sensitizers.
  • the used amount of the sensitizer is preferably in general within the range of not higher than 400 parts by weight based on 100 parts by weight of the color developer.
  • the method for forming the recording layer is not especially restricted. It may be formed by a method, for example, in which a coating solution for forming a heat-sensitive recording layer is applied on a base sheet by a known coating process such as air knife coating, rod blade coating, pure blade coating and short dwelltime coating and dried.
  • the amount of the coating composition applied is not also especially restricted but usually controlled within the range of 2 to 12 g/m2, preferably 3 to 10 g/m2 on dry basis.
  • the retainability of the recorded image can be further improved by providing a protective layer on the heat-sensitive recording layer.
  • the protective layer is generally formed by using a water-soluble or water-dispersible polymer as the main component.
  • a water-soluble or water-dispersible polymer As the polymers, there are exemplified various binders as mentioned above. Among them, carboxyl-modified polyvinyl alcohol, acetoacetyl-modified polyvinyl alcohol and silicon-modified polyvinyl alcohol are most preferably used because they are excellent in the effect as the protective layer.
  • curing agents such as glyoxal, formalin, glycine, glycidyl ether, dimethylol urea, ketene dimer, dialdehyde starch, melamine resin, polyamide resin, polyamide-epichlorohydrin resin, ketone-aldehyde resin, borax, boric acid, zirconium ammonium carbonate and epoxy compounds may be also used in combination.
  • inorganic pigments such as calcium carbonate, zinc oxide, aluminum oxide, titanium dioxide, silicon dioxide, aluminum hydroxide, barium sulfate, zinc sulfate, talc, kaolin, clay, calcined kaolin and colloidal silica, and organic pigments such as styrene microballs, nylon powder, polyethylene powder, urea-formaldehyde resin filler and raw stanch particles may be added to the protective layer if required.
  • the added amount of the pigment is preferably controlled within the range of 5 to 500 parts by weight based on 100 parts by weight of the binder.
  • lubricants such as zinc stearate, calcium stearate, polyethylene wax, carnauba wax, paraffin wax and ester wax, and surface active agents (dispersants and lubricants) such as sodium dioctyl sulfosuccinate and antifoaming agents.
  • the coating composition for forming the protective layer thus prepared may be coated on the heat-sensitive recording layer by a suitable coating equipment.
  • the used amount of the coating composition is preferably controlled within the range of 0.1 to 20 g/m2, more preferably 0.5 to 10 g/m2, in general, as the recording sensitivity of the heat-sensitive recording material is lowered when the amount applied exceeds 20 g/m2.
  • the retainability of the recorded image may be further improved if required by providing a protective layer also on the back of the heat-sensitive recording material.
  • a protective layer also on the back of the heat-sensitive recording material.
  • various known technologies in the field of producing the heat-sensitive recording material such as formation of primer layer on the base sheet and application of an adhesive on the back of the recording material to make an adhesive label.
  • a primer layer may be formed between the base sheet and the heat-sensitive recording layer.
  • the primer layer there may be included such inorganic or organic pigments and binders as described above. Oil-absorbing pigments are preferably used.
  • paper As the base sheet, paper, plastic film and synthetic paper and the like may be used. Paper is most preferably used in terms of cost and coatability.
  • composition was pulverized in a sand mill, and the pulverization was continued until an average particle size of 0.8 ⁇ m.
  • composition was pulverized in a sand mill, and the pulverization was continued until an average particle size of 1.2 ⁇ m.
  • composition was pulverized in a sand mill, and the pulverization was continued until an average particle size of 1.2 ⁇ m.
  • composition was pulverized in a sand mill, and the pulverization was continued until an average particle size of 2.1 ⁇ m.
  • Dispersion A 55 parts of Dispersion A, 115 parts of Dispersion B, 80 parts of Dispersion C, 24 parts of Dispersion D, 80 parts of 10 % aqueous solution of polyvinyl alcohol and 35 pots of calcium carbonate were mixed together under stirring and the resultant coating composition was coated in the weight of an amount of 6 g/m2 on dry basis on a base paper sheet of 50 g/m2 and dried to obtain a heat-sensitive recording material.
  • a heat-sensitive recording material was prepared in the same manner as in Example 1 except that 1,4-diglycidyl phthalate (Trade name "Denacol EX-711" manufactured by Nagase Kasei Kogyo Co., Ltd., melting point: 100°C ) was used instead of 1,4-di(glycidyloxy)benzene to prepare Dispersion D.
  • 1,4-diglycidyl phthalate Trade name "Denacol EX-711” manufactured by Nagase Kasei Kogyo Co., Ltd., melting point: 100°C
  • a heat-sensitive recording material was prepared in the same manner as in Example 1 except that 1-phenoxy-14-glycidyloxy-3, 6,9,12-tetraoxatetradecane (Trade name "Denacol EX-145" manufactured by Nagase Kasei Kogyo Co., Ltd., aqueous solution ) was used instead of 1,4-di(glycidyloxy)benzene to prepare Dispersion D.
  • 1-phenoxy-14-glycidyloxy-3, 6,9,12-tetraoxatetradecane (Trade name "Denacol EX-145" manufactured by Nagase Kasei Kogyo Co., Ltd., aqueous solution ) was used instead of 1,4-di(glycidyloxy)benzene to prepare Dispersion D.
  • a heat-sensitive recording material was prepared in the same manner as in Example 1 except that Dispersion D was not added to the coating composition for forming the recording layer.
  • a heat-sensitive recording material was prepared in the same manner as in Example 1 except that bis-(4-hydroxyphenyl) sulfone was used instead of 2,4′-dihydroxydiphenylsulfone to prepare Dispersion B.
  • a heat-sensitive recording material was prepared in the same manner as in Example 2 except that 4,4′-isopropylidene diphenol was used instead of 2,4′-dihydroxydiphenylsulfone to prepare Dispersion B.
  • the whiteness of the recording layer was measured by using a Hunter reflectometer.
  • the heat-sensitive recording material was treated at 50 °C for 15 hours and then the whiteness of the recording layer was measured by using a Hunter reflectometer.
  • the color density of the recorded image obtained by printing with a thermal printer was measured by using a Macbeth densitometer (RD-914 manufactured by Macbeth Corp.).
  • a polyvinyl chloride film manufactured by Mitsui Toatsu Kagaku Co., Ltd. was wrapped threefold around a polypropylene pipe having a diameter of 40 mm.
  • a heat-sensitive recording material after developing color image was put on it in a manner the color images are exposed outward and further the same polyvinyl chloride film was wrapped threefold around the heat-sensitive recording material.
  • the resultant material was stood at 30°C for 24 hours and the color density was measured to evaluate plasticizer resistance.
  • a heat-sensitive recording material was prepared in the same manner as in Example 1.
  • a recording layer was formed on the base sheet in the same manner as in Example 2.
  • a protective layer was formed on the above recording layer in the same manner as in Example 4 to obtain a heat-sensitive recording material having a protective layer.
  • a recording layer was formed on the base sheet in the same manner as in Example 3.
  • a protective layer was formed on the above recording layer in the same manner as in Example 4 to obtain a heat-sensitive recording material having a protective layer.
  • a heat-sensitive recording layer was formed on the substrate in the same manner as Example 1.
  • a protective layer was formed on the above recording layer in the same manner as in Example 4 to obtain a heat-sensitive recording material having a protective layer.
  • a heat-sensitive recording layer was formed in the same manner as in Comparative Example 1.
  • a protective layer was formed on the above recording layer in the same manner as in Example 4 to obtain a heat-sensitive recording material having a protective layer.
  • a heat-sensitive recording layer was formed in the same manner as in Comparative Example 2.
  • a protective layer was formed on the above recording layer in the same manner as in Example 4 to obtain a heat-sensitive recording material having a protective layer.
  • a heat-sensitive recording layer was formed in the same manner as in Comparative Example 3.
  • a protective layer was formed on the above recording layer in the same manner as in Example 4 to obtain a heat-sensitive recording material having a protective layer.
  • a substrate for a heat-sensitive recording material prepared in the same manner as in Example 7.
  • a heat-sensitive recording layer was formed on the substrate in the same manner as in Comparative Example 1 except that the above substrate was used.
  • a protective layer was formed on the above recording layer in the same manner as in Example 4 to obtain a heat-sensitive recording material having a protective layer.
  • a polyvinyl chloride film manufactured by Mitsui Toatsu Kagaku Co., Ltd. was wrapped threefold around a polypropylene pipe having a diameter of 40 mm.
  • a heat-sensitive recording material after developing color images was put on it in the manner color images are exposed outward and further the same polyvinyl chloride film was wrapped threefold around the heat-sensitive recording material.
  • the resultant material was stood at 40 °C for 24 hours and then the color density was measured to evaluate plasticizer resistance.
  • the heat-sensitive recording material after developing color images was slightly wet with water and then evaluated in the same manner as in the above plasticizer-resistance test to give wet plasticizer-resistance.
  • the heat-sensitive recording material according to the present invention is excellent in storage stability (retainability of images) and shows no fogging.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Heat Sensitive Colour Forming Recording (AREA)
EP19910308649 1990-09-27 1991-09-23 Wärmeempfindliches Aufzeichnungsmaterial Expired - Lifetime EP0478263B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP260085/90 1990-09-27
JP2260085A JPH04135789A (ja) 1990-09-27 1990-09-27 感熱記録体

Publications (2)

Publication Number Publication Date
EP0478263A1 true EP0478263A1 (de) 1992-04-01
EP0478263B1 EP0478263B1 (de) 1994-02-16

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP19910308649 Expired - Lifetime EP0478263B1 (de) 1990-09-27 1991-09-23 Wärmeempfindliches Aufzeichnungsmaterial

Country Status (3)

Country Link
EP (1) EP0478263B1 (de)
JP (1) JPH04135789A (de)
DE (1) DE69101205T2 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE39835E1 (en) * 1999-10-11 2007-09-11 Rustom Sam Kanga UV-absorbing support layers and flexographic printing elements comprising same

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5565402A (en) * 1994-07-26 1996-10-15 New Oji Paper Co., Ltd. Heat sensitive recording material
CN114945976A (zh) 2020-01-20 2022-08-26 鼓工场有限公司 电子音乐乐器和系统
JP2025524809A (ja) 2022-07-21 2025-08-01 ドラム ワークショップ， インコーポレイテッド 電子楽器、システム、及び方法

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 13, no. 588 (M-912)(3936) 25 December 1989 & JP-A-01 247 192 ( NIPPON KAYAKU K.K. ) 3 October 1989 *
PATENT ABSTRACTS OF JAPAN vol. 4, no. 132 (M-32)(614) 17 September 1980 & JP-A-55 087 596 ( RICOH K.K. ) 2 July 1980 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE39835E1 (en) * 1999-10-11 2007-09-11 Rustom Sam Kanga UV-absorbing support layers and flexographic printing elements comprising same

Also Published As

Publication number Publication date
DE69101205T2 (de) 1994-09-08
DE69101205D1 (de) 1994-03-24
JPH04135789A (ja) 1992-05-11
EP0478263B1 (de) 1994-02-16

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