JPS5954597A - Sheet for multicolor recording heat-sensitive label - Google Patents

Abstract

PURPOSE:To obtain a sheet being free from the stain due to printing and stamping, enabling multicolor recording and being best fitted to a label and other uses requiring affixation after printing, by a method wherein a multicolor-forming heat-sensitive layer of a specified synchronous color-discharging and color- forming system and a film layer formed of alginate are provided on a tack- processed supporting substance. CONSTITUTION:In tack-processed paper prepared by providing a pressure-sensitive adhesive layer 2 on one surface of a supporting substance 3 and further affixing release paper 1 thereon, multicolor-forming heat-sensitive layers 4 and 5 made by combining phenolic material (e.g. 4,4'-isopropylidenediphenol) or organic acid, a dye precursor (e.g. crystal violet lactone) whose color can be formed in heat by said phenolic material or organic acid, organic base, and a dye precursor whose color can be formed in heat by said organic base, as the main elements, are provided on the other surface of said supporting substance 3, and further an over coat layer 6 is provided thereon by using alginate solely, or the alginate as a requisite and one or more kinds of other water-soluble high polymer compounds together therewith. An aimed sheet is obtained in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides barcode dowels for POS (point of sale) systems, price display labels, and other shipping and
The present invention relates to a multicolor recording heat-sensitive label sheet that is suitable for applications that require post-printing, such as shipping labels, product journal patches, stamps, and mailing stickers.

In recent years, POS systems have become extremely popular in large-scale mass retailers such as supermarkets and department stores, as well as chain specialty stores and restaurants.

In order to clearly understand the needs of consumer diseases and formulate a rational management strategy, one of the purposes is to collect and analyze product sales and sales information. 4. Scan barcodes and OCR characters displayed on Hansai products with a scanner. The +6 reading method is currently developing rapidly, and it is expected that its use will further expand in the future for qliR slips, stamps, etc.

Therefore, various printing methods are currently being tried, and among them, the thermal recording method can be said to be the most excellent.

This is because the printing method uses chemical or physical changes in substances due to heating to record images.
There is no need for developing and fixing, and there is no need to replenish printing ink1.In other words, the machine is smaller and simpler, and the recording speed is faster. This is because it has many features such as not having to worry about it at all.

However, barcode labels, price display labels, other slips, stamps, etc. have multiple items written on them, and are useful for users such as consumers and sales staff as multicolored records with vivid colors. is required.

Conventionally, there are many examples of multicolor thermal paper. Generally, it is conceivable to apply two heat-sensitive layers having different coloring temperatures and coloring hues in three layers. For example, by using a phenolic substance 51 and an organic acid and two or more dye precursors that develop color with the phenolic substance or organic acid, and by making use of the difference in melting point between the layers by laminating them, a single color can be produced by heating at a low temperature. 11 So-called mixed color type that develops different hues by mixing colors at high temperatures.

('i Publication No. 48-15540) In addition, two or more dye precursors that develop color with a phenolic substance or organic acid and the phenol or other substance or organic acid may be used in the laminated heat-sensitive layer or , IWf melts at a higher temperature than the fuconolic substance or organic acid in the adjacent layer.
By containing an organic base, the color once developed by heating does not fade at temperatures above the melting temperature of the organic base, and by reducing the degree of color mixing, different hues that are close to a single color can be created. It is a so-called colorless thread that develops color. (4￥ Kaisho 48-8251, JP 55-139290, 11'!1': Kaisho 55-
No. 161688) Furthermore, by co-mixing a dye precursor capable of developing a different color with the organic base into such a system, so-called erasing can be achieved, which simultaneously develops a different hue of a single color. Simultaneous color and color development system (Special Publication Publication No. 51-3
No. 7542).

However, in the case of mixed color yarns, the single color that can be produced at a low temperature has the disadvantage that it is limited to a lighter hue compared to the mixed color that can be produced at a higher temperature.

In other words, colors such as red (low temperature) - black (high temperature), blue (low temperature) - black (high temperature), yellow (low temperature) - black (high temperature), etc. are produced, and a large amount of heat is required to print the black color that occupies the majority of the recorded area. needs a mouse,
It is impractical because it goes against energy conservation and speed improvement.

In addition, color separation is difficult, and it is necessary to widen the melting point difference between layers sufficiently, resulting in a decrease in color development speed and a large amount of heat.
1:, which causes trouble during recording.

1. In the case of color-erasing thread, a basic substance is simply used as a color-erasing agent, and when coloring at a high temperature, coloring is again done with a phenolic substance or a specific acid in the same way as when coloring at a low temperature, resulting in high costs. At present, there are many problems such as difficulty in balancing the interlayer composition, and a large amount of heat required.

Therefore, the color erasing and color development simultaneous system was invented to solve the above two systems, and high temperature color development progresses quickly using a basic substance that erases low temperature color development, making it extremely efficient and clear. Of course, black (low temperature) - red (
The advantage of being able to print frequently recorded characters such as high temperature), blue (low temperature) - red (high temperature), black (low temperature) - yellow (high temperature) at low temperatures can also be applied to energy saving and speeding up recording. As we move from an era when multi-color printing was only possible with thermal pens to an era where multi-color printing was desired even with thermal printers and thermal facsimiles, it has become possible to say that it is the system that most lives up to expectations. .

However, the quality required for heat-sensitive label sheets is as follows: (1) The coating layer does not peel off and the recorded area remains clear and does not smear even if it gets wet or gets damaged by rain. thing. (2) If your hands are wet with edible oil such as tempura oil, hand cream or hair styling oil, or if you come into contact with packaging film containing a high amount of plasticizer for a long period of time, the recording section will be discolored and become unreadable. Don't be difficult or impossible. There are two points to mention.

In order to satisfy the requirement of (1), it is possible to improve the effect to some extent by adding a water-resistant agent or a water-repellent to the water-soluble polymer compound used as the binder in the heat-sensitive coating layer, but the pigment contained in the coating layer It is impossible to form a complete film-like coating due to the influence of color developers, dye precursors, etc.Also, increasing the amount of binder can be considered, but this results in a decrease in color development sensitivity.

As a result of investigation, it has been found that the most effective method is to provide an overcoat layer that provides water resistance on the surface of the heat-sensitive layer. Furthermore, this method does not satisfy the requirement (2). That is, it has been proposed that such a phenomenon will not occur if a plasticizer such as dibutyl phthalate, dioctyl phthalate, or dioctyl adipate forms a L7 film for the purpose of preventing penetration into the heat-sensitive layer. (Japanese Unexamined Patent Applications No. 54-128347, No. 54-3549) The present inventors have also developed overcoating agents with chemical resistance, and Japanese Patent Applications No. 55182557 and No. 56-981
No. 7 has been filed.However, when printing or stamping different hues on monochromatic thermal paper with an overcoat layer, it is necessary to use an ink set to ensure that there is almost no seepage into the paper surface. The bad news is that it stains your hands and clothes and makes it illegible.

As a result of our investigation, we found that when an overcoat layer is provided on a heat-sensitive recording sheet capable of producing multiple colors, printing by heat,
It has been found that the seal can be easily and clearly printed in multiple colors.

The present inventors (・”5, based on their background (1), (
With the aim of meeting the requirements (11' to 11'), the present invention was achieved as a result of intensive study on a heat-sensitive label sheet capable of multicolor recording without staining printing marks.

111" In other words, the present invention provides a tack-processed support, a dark color-simultaneous color-developing heat-sensitive layer on the other side, and an alginate alone or an alginate as an essential component on the N-side of the support. A film-like coating layer containing additives such as water resistant agents, water repellents, antifoaming agents, and ultraviolet absorbers, using one or more types of polymer compounds in combination. That we have set it up! [An object of the present invention is to provide a heat-sensitive label sheet capable of multicolor recording.

The main components used in the present invention will be explained in detail below, but the present invention is not limited thereto unless it exceeds the gist of the present invention.

Representative examples of dye precursors that develop color with phenolic substances and organic acids are shown in Table 1.

Table-1 (1) Crystal binolet lactone (2)
3-indolino-3-p-dimethylaminophenyl-
6-dimethylaminophthalide (3) 3-diethylamino-7-lylolofluorane (4) 3-diethylamino-7-cyclohexylaminofluorane (5) 3-diethylamino-5-methyl-7-t-butylfluocine (6) 3 -diethylamino-6-methyl-anilinofluorane (7) 3-diethylamino-6-methyl-7-p
-Butylanilinofluorane (8) 2-(N-phenyl-N-ethyl)aminofluorane (9) 3-diethylamino-7-dibenzylaminofluorane (10) 3-cyclohexylamino-6-chlorofluorane (1t) 3-diethylamino-6-methyl-7-xylidinofluorane (12) 2-anilino-3-medito-16-(N-
Ethyl-phluidino)fluorane (13) 3-pyrrolidino-6-medyl-7-anilinofluorane (14) 3-pyrrolidino-7-cyclohexylaminofluorane (15) 3-piperidino-6-medyl-7- Toluidinofluorane (1G) 3-piperidino-6-methyl-7-anilinofluorane (17) 3-(N-methylcyclohexylamino)-6-methyl7-anilinofluorane (,18) 3 -diethylamino-7-(m-)lifluoromethylanilino)fluoran (19) 3-diethylamino-6-medy-7-chlorofluoran is also used in the present invention as a dye precursor that develops color with an organic base. Ninhydrin is a pH indicator that develops color or changes color in alkaline conditions, fluorescein derivatives, phenolphthalein derivatives, and ninhydrin, a substance that causes discoloration due to oxidation or oxidation in a broad sense due to a change in pH value to the alkaline side. Derivatives etc. are used.

Typical examples are shown in Table-2.

Table-2 <3> (4) (15) (16) Azolitomine Hemadoxylin (17)
(i8) (23)
(24) <33> (
34) (37) (38) (4
1) (42) (43)
(44) (45) (
・16)C]c] (4g) (5(1)(51
) (52) (53)
(5,1) (63)
(64) C1 (65) Next, typical examples of the phenolic substance or organic acid (color developer) used in the present invention are shown in Table 3.

Table 3 (1) 4.4'-Infuropylidenediphenol (
2) 4.4'-Impropylidene bis(2-glorphenol) (3) 4.4'-Impropylidene bis(
2-tert-butyl<4) 4.4'-Secondary-butylidene diphenol (5) 4.4'-(t-
Methyl-n-hexylitine)diphenol (6) 4-phenylphenol (7) 4-hydroxydiphenoxide (8) Methyl-4-monohydroxybenzoate (9) Phenyl-
4-hydroxybenzoate (1 (1) 4-hydroxybenzoate (11) Naridi-anilide (12) 4.4'-cyclohexylidene diphenol (13) 4.4'-cyclohexylidene bis (2
-methylphenol) (14) 4.4'-”<7
':'') T-diphenol (15) 4゜4'-Thiobis(6-tert-butyl-3-mebulphenol) (16) 4.4'-Inpropylidenebis(2-methylphenol) (17) 4.4'-Edylenebis(2-methylphenol) (18) 4.4'-Cyclohexylidenebis(2-inflovirphenol) (19) 2.2'-Dihydroxydiphenyl (2
0) 2.2'-methylenebis(4-chlorophenol) (21) 2.2'-methylenebis(4-methyl-6-t-butylphenol) (22) 1.1'--bis(4-hydroxyphenol) -Cyclohexane (23) 2.2-bis(4'-hydroxyphenyl)furopane (24) Novolac type phenolic resin (25) Halogenated novolac type phenolic resin (26
) α-naphthol (27) β-naphthol (28) 3.5-di-t-butylsalichinoycoal (2
9) 3.5-di-α-methylbenzylsalicylic acid (
30) 3-Methyl-5-t-butyl salicylic acid (
31) Phthalic acid monoanilide paraethoxybenzoic acid (3
2) Parabenzyloxybenzoic acid (33) Parahydroxybenzoic acid benzyl ester Furthermore, as the organic base used in the present invention, when the melting point is too low or the water solubility is very high, it is used. There is a high possibility that the heat-sensitive layer will change color during storage, and if the basicity is too low, it is difficult for the heat-sensitive layer to discolor or develop color, which is not preferred in practice.

Among the organic bases used in the present invention, guanidine derivatives are particularly excellent in practical use, and specific examples are listed in Table 4A, but these are not intended to limit the present invention.

1 in the table indicates a cyclohexyl group.

Table-4A (11) (12) (21)
(22)1 NN(-C-NN2 (27) (2B)t)
(32) (40) (41)NH
NU N'kl NH 1 NH Other than the above-mentioned guanidine derivatives, organic bases that can be used in the present invention are shown in Table 4B, but are not limited to the present invention.

Table 4B (49) Phenylthio log (50) Hegizadecylamine (51) Tribenzylamine (52) N, N, N', N'-Tetrabenzyl-ethyl 7-diamine (53) N, N, N', N' -detrabenzyl-hexamethylene diamine (54) decamedylene diamine (55) ) +) cyclohexylamine (56)
N,p+'-dibenzylpiperazine (57)
Dioctadecylamine (58) 2-aminobenzimidazole (59)
2-aminobenzodeazole (60) 2-aminobenzimidazole (61) quinine (62) cyclohegycyldibenzylamine (63)
Octalanisylbenzylamine The thermal recording paper of the present invention can be obtained by the following method. That is, a phenolic substance or an organic acid, a dye precursor that develops color with the phenolic substance or organic acid, an organic salt, and a dye precursor that develops a color with the organic base are pulverized separately or during PFI using a pulverizer. A coating liquid is prepared by crushing and dispersing the powder into single grains, mixing with a binder, pigment, etc. in an appropriate combination, and adding various additives as necessary.

Examples of binders and l- include starches, hydroxybutylcellulose, mefur cellulose, polyvinyl alcohol, styrene-maleic anhydride copolymer, styrene-butadiene copolymer, polyacrylamide, carboxymethylcellulose, Arabico J1, casein. and latexes such as styrene-butadiene latex can be used.

Examples of pigments include aluminum hydroxide, heavy and sulfuric calcium carbonate, zinc oxide, titanium oxide, barium sulfate, silica gel, activated clay, talc, clay, sadin white, kaolinite, calcined kaolinite, diatomaceous earth, and synthetic kaolinite. Night, polyolefin grains, Boristi V
granules, urea-formalin resin granules, etc.

Next, regarding the material forming the overcoat layer in the present invention, water-soluble polymer compounds are generally preferred;
Among them, alginate, alginate, and alginate are essential, and they are used in combination with one or more polymeric compounds selected from hydroxyl cellulose, methyl cellulose, carboxymethyl cellulose, and polyvinyl alcohol. Things are good. (% Gansho 56-15245
No. 5) In addition, one or more types of water resistant agents, water repellents, antifoaming agents, and ultraviolet absorbers are used in combination to impart water resistance and light resistance, and to prevent the formation of pinholes. Preferably, it is prevented.

Further, in the present invention, the thickness of the overcoat layer as a dry film is 0.5 μm or more, preferably 3 to 12 μm.
m is desirable from the viewpoint of heat-sensitive properties, oil and fat resistance, and plasticizer resistance. If the thickness of the film is thinner than 0.5 μm, the heat-sensitive characteristics
It has sufficient anti-scum/sticking and fingerprint smudge resistance as well as oil/grease/plasticizer resistance, and Id', 'fl:<, and 1
If the diameter exceeds 2 μm, the resistance to dust, swiping, fingerprint stains, and oil/grease/surface plasticity is good, but the color development sensitivity tends to decrease. Explain in detail.

This is an example of the combination and coating method of each 8i material, and the coating method such as combination force, single layer, lamination, etc. does not limit the present invention.

The figure is a cross-sectional view of a sheet for heat-sensitive labels of the present invention, in which a support 3 is provided with a pressure-sensitive adhesive (hereinafter referred to as adhesive) layer 2 with a release paper 1 attached thereon, and the other side is provided with a pressure-sensitive adhesive (hereinafter referred to as adhesive) layer 2. -A
and layer 4, which has the function of decolorizing agent and coloring agent when heated at high temperature, whose main component is the organic base shown in Table 4-B, and the phenolic substances or organic acids shown in Table 3, and Table 1
If the phenolic substance shown in 7 or a dye precursor that can develop color when heated with an organic acid and a dye precursor that can develop a color when heated with an organic base shown in Tables 4-A and 4-B are the main components. Coloring layers 5 that develop a single color when heated at a low temperature and develop other hues when heated at a high temperature are sequentially laminated.

These heat-sensitive coloring layers are further provided with an overcoat (i6) consisting of alginate alone or in combination with alginate as an essential component and at least two or more other water-soluble polymer compounds.

More specifically, as release paper, for example, paper whose surface is treated with a release agent such as silicone resin is generally used, but as a base material, -C can be used in addition to paper, such as synthetic paper, It can also be used with synthetic resin films, etc.

In addition, examples of adhesives include hot-melt adhesives mainly composed of styrene/butadiene block copolymers, styrene/inzolene block copolymers, etc., and rubbers such as natural rubber latex and inbutylene latex. Examples include emulsion type adhesives, acrylic emulsion type adhesives, etc., but these do not limit the present invention unless they go beyond the gist of the present invention.

The support to which the heat-sensitive coating liquid is applied is generally paper, but any material such as synthetic paper or synthetic resin film can also be used.

Next, embodiments of the present invention will be described in detail with reference to drawings.

Example A liquid )3ft.

Solution C Solution D The above solutions A, D, C, and D were separately ground and dispersed in a ball mill for 48 hours.

Using the thus dispersed liquids A, B, C, and 1), a heat-sensitive coating liquid was prepared as follows.

Undercoat layer coating liquid: Layer 4 in the figure 50? The coating was applied to a base paper having a basis weight of 3.6 y/m' after drying, and dried at 60° C. for 1 minute to prepare an undercoated paper.

Top coat layer coating liquid: Layer 5 in the figure Ancillex (Engelhard KK!JL calcined kaolin)・・・・・・・・・・・・・・・・・・・・・・・・
・・・ 202 Mata Wed ・・・ ・・・・・・・
・ 552 What is the coating amount of the coating liquid prepared as above on the undercoat paper after drying? -49/m' and dried at 60° C. for 1 minute to produce multicolor thermal paper with simultaneous color erasing and color development. The multicolored thermal paper develops colors with a sharp contrast of black when heated at low temperatures and red when heated at high temperatures.

Overcoat layer: Layer 6t in the figure, a mixture of sodium alginate/carboxymethyl cellulose - 1/1 (weight ratio) and an epoxy crosslinking agent (trade name: Ebiol G-100)
(manufactured by NOF Corporation) was added at a weight ratio of 0.1, and was coated on the multicolor thermal paper so that the thickness of the film after drying was approximately 4 μm. After drying, it was supercalendered and pasted with tacked paper. In addition, a desired multicolor recording heat-sensitive label sheet was obtained.

In this way, I (my wife's multicolor recording heat-sensitive label sheet)
Images with sharp contrast between black and red can be printed.
It fully satisfied the light resistance, water resistance, oil resistance, and plasticizer resistance required for uses such as labels, and was also satisfactory with no scum or sticking during printing.

[Brief explanation of the drawing]

The figure is a sectional view of a sheet for a multicolor recording heat-sensitive label of the present invention. 1...Release paper 2...Adhesive layer (hatched area) 3...Support 4...Layer 5 which functions as a decoloring agent and coloring agent when heated at high temperature 5... Layer 6, which obtains a monochromatic color when heated at a low temperature and obtains color development of other hues when heated at a high temperature... - Overcoat layer (dotted part) ○ mark: phenolic substance or organic acid ◎ mark...
・Dye precursor that develops color when heated due to a phenolic substance or organic acid ・・Organic base symbol: Indicates a dye precursor that develops color when heated due to an organic base.

Claims (1)

[Claims] In a tacked paper in which a pressure-sensitive adhesive layer is provided on one side of a support and a release paper is attached, the other side of the support is coated with a phenolic substance or an organic acid, and is heated with the phenolic substance or organic acid. A multicolor color-forming heat-sensitive layer made of a single layer or a laminated layer of a dye precursor capable of coloring upon heating, a specific base, a dye precursor capable of coloring with the organic base, and a dye precursor capable of coloring upon p-heating, and gold as the main element. A multicolor recording heat-sensitive label characterized in that an overcoat layer is provided on the surface of the alginate alone, or an overcoat layer consisting of alginate as an essential component and one or more other water-soluble polymer compounds. Sheet for use.