JPH04107076U - Transparent film-based thermal label - Google Patents

Abstract

(57) [Summary] [Purpose] To manufacture thermal recording labels of any color easily and at low cost by coloring the adhesive layer provided on the back side of the support so that the printed matter can be easily seen. [Structure] In a heat-sensitive label in which a release paper is attached to the back side of a support 1 via an adhesive layer 2, and a heat-sensitive recording layer containing a leuco compound and a color developer as coloring components is provided on the surface of the support. , the adhesive layer 2 is a colored adhesive layer, and the support is made of a transparent synthetic resin film.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a heat-sensitive label on which an image can be recorded using a heat-sensitive recording method.

0002

[Prior art and its problems to be solved]

Generally, labels are product labels used to display the capacity, price, quality, etc. of a product. , address display labels attached to mailed items or office labels used for organizing documents, etc. It is used in many ways, such as as a file. A type of label like this is printed using a thermal recording method. There are heat-sensitive labels that can record images of characters.

0003 Thermal recording method does not require a development and fixing process, and requires maintenance of printing equipment (hardware). Recently, various printers and facsimiles have been used because they have features such as easy maintenance. It is widely used for recording in measuring equipment, recording television images, etc. these The required characteristics of the heat-sensitive recording material used for recording vary depending on the application, but recently it has become more Dot reproducibility of thermal recording media is required to be able to record images with intermediate tones (densities). ing.

0004 The base materials used for the support of thermosensitive recording materials include various sheet-like base materials such as paper and synthetic materials. Film-like substrates such as resin films are known. However, in general, paper etc. Although sheet-like substrates are inexpensive, they have drawbacks in dot reproducibility and color development. Synthetic resin cover Film-like substrates such as films do not have these drawbacks, but the heat-sensitive recording layer and support are If it is transparent, it is difficult to see what is printed, so white pigment is added to the heat-sensitive recording layer. and the gloss of the support is lost.

[0005] The problem of this invention is to solve the above-mentioned conventional drawbacks and to create colored labels in arbitrary colors. It is an object of the present invention to provide a heat-sensitive label that can be manufactured by simple means at low cost.

[0006]

[Means to solve the problem] This invention solves the above problems by coloring the adhesive layer provided on the back side of the support. This is the solution. In other words, the gist of the present invention is that adhesive is attached to the back surface of the support. A release paper is pasted through the adhesive layer, and a leuco compound and a color developer are released on the surface of the support. In a heat-sensitive label equipped with a heat-sensitive recording layer containing color components, the adhesive layer is It is a colored adhesive layer, and the support is made of a transparent synthetic resin film. This is a transparent film-based heat-sensitive label characterized by having the following structure. Note that a thermal head may be placed on top of the heat-sensitive recording layer of the present invention to protect the heat-sensitive recording layer. An overcoat layer may be provided to improve the runnability of the board.

[0007] Each element constituting the present invention will be explained in more detail below. First of all, to explain the support, the synthetic resin used for the support of this invention. As the material, conventionally known materials can be used, such as polyethylene and polypropylene. polyethylene terephthalate, polycarbonate, polystyrene, nylon , cellulose diacetate, cellulose triacetate, etc., but heat-resistant Biaxially oriented polypropylene is preferred from the viewpoint of properties, cost, etc. these polyethi Additives commonly used in resins such as polypropylene and polypropylene, such as antioxidants and Antistatic agents, slip agents, etc. may also be used. If necessary, corona may be added to the above support. By performing electrical discharge treatment or coating with ionomer resin, the support and heat-sensitive recording The adhesion of the layer can be improved. The above support is a transparent synthetic resin film in order to see through the colored layer described below. It is necessary that

[0008] The release paper provided on the back side of the support and the adhesive layer that adheres it to the support are Any of those used in conventional peelable labels can be used. For example, with release paper For example, a peeling layer such as silicone resin is provided on a mount such as paper, or a material used for the adhesive layer. The adhesives used are basically made up of the following elastic material and tackifying material. Can be used. (i) Elastic body: recycled rubber, SBR (styrene-butadiene rubber), polyisoplast Ren, butyl rubber, Buna-N (butadiene/acrylonitrile rubber), polyvinyl polyether (ethyl or higher), polyacrylate ester (ethyl or higher) (more than that). (ii) Tackifier: polyterpene resin, gum rosin, rosin ester and rosin Gin derivatives, oil-soluble phenolic resins, coumaron indene resins, petroleum hydrocarbon resins Fat. In the present invention, it is possible to use a coloring agent added with the following coloring agent. sticky White pigments, other coloring pigments, dyes, etc. are used when coloring the adhesive. The adhesive layer of the present invention is obtained. For example, white pigments include titanium oxide, zinc oxide, Barium sulfate, calcium carbonate, talc, clay, melamine resin, urea formalin Organic or inorganic pigments such as resins and acrylic resins are used as coloring pigments or dyes. , ocher, sienna, amber, chrome yellow, prussia blue, methyl bio Examples include various organic or inorganic pigments or dyes such as red, malachite green, etc. Ru.

[0009] The leuco compound, color developer, and binder that make up the heat-sensitive recording layer are conventionally known ones. is used, an example of which is shown below. Leuco compounds are colorless or light-colored, and develop color when they react with the organic acids described below. It is a substance that Oran series, leuko-olamine series, diphenylmethane series, phenothiazine series, phenothiazine series, Various derivatives such as noxazine series, spiropyran series, indoline series, and indigo series Can be mentioned. Preferred leuco compounds include, for example, crystal violet Chthone, 3-diethylamino-6-methyl-7-anilinofluorane, 3-(N -ethyl-p-toluidino)-6-methyl-7-anilinofluorane, 3-die Thylamino-6-methyl-7-(ortho, para-dimethylanilino)fluoran , 3-pyhelidino-6-methyl-7-anilinofluorane, 3-(N-cyclohexane) xyl-N-methylamino)-6-methyl-7-anilinofluorane, 3-die Thylamino-7-(ortho-chloroanilino)fluoran, 3-diethylamino -7-(meta-trifluoromethylanilino)fluorane, 3-diethylamino -6-methyl-chlorofluorane, 3-diethylamino-6-methyl-fluorane 3-(N-isoamyl-N-ethylamino)-6-methyl-7-anilinof fluorane, 3-dibutylamino-6-methyl-7-anilinofluorane, etc. It will be done.

0010 Acidic substances used as color developers are solid at room temperature, melt when heated, and become rotten. A substance that becomes a color developer when it comes into contact with an ico compound, including various phenolic substances and fats. Examples include gallic acid, salicylic acid, and 1-hydrocarboxylic acid. roxy-2-naphthoic acid, o-hydroxybenzoic acid, m-hydroxybenzoic acid, 2-hydroxy-p-toluic acid, 3,5-xylenol, thymol, p- tert-butylphenol, 4-hydroxyphenol, methyl-4-hydroxy Cybenzoate, 4-hydroxyacetophenone, α-naphthol, β-naphtho -ol, catechol, resorcinol, hydroquinone, 4-tert-octylcatechol , 4,4'-sec-butylidenephenol, 2,2'-dihydroxydiphenyl , 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2, 2'-bis(4-hydroxyphenyl)propane (also known as bisphenol A), 4,4'-isopropylidene bis(2-tert-butylphenol), pyrogallo- phloroglucin, phloroglucin carboxylic acid, p-methylphenol, p- Phenylphenol, 4,4'-cyclohexylidene diphenol, 4,4'- Isopropylidene dicatechol, 4,4'-benzylidene diphenol, 4,4 '-Isopropylidene bis(2-chlorophenol), 3-phenylsalicylic acid , 3,5-di-tert-butylsalicylic acid, 1-oxy-2-naphthoic acid, gallic acid ester, salicylic acid ester, p-hydroxybenzoic acid ester, 4-hydro Xyphthalic acid ester, 2-(4-hydroxyphenyl)2-(3'-hydroxy Cyphenyl)propane, 4,4'-dihydroxy-3,3'-diisopropyldi Examples include phenyl-2,2'-propane.

[0011] The binder used in the heat-sensitive recording layer mainly consists of a water-soluble binder, and fine particles A dye and a color developer that are dispersed in the form of particles are separated from each other and fixed. Vinyl alcohol, epoxy modified polyvinyl alcohol, methyl cellulose, carbon Ruboxymethyl cellulose, hydroxyethyl cellulose, polyacrylic acid, carbon Examples include zein, gelatin, starch and derivatives thereof.

0012 The heat-sensitive recording layer of the present invention may contain other additives, such as clay and calcium carbonate, as necessary. Inorganic materials such as aluminum, synthetic silica, aluminum hydroxide, talc, titanium oxide, zinc oxide, etc. Or organic pigments, antioxidants for storage stability, ultraviolet absorbers, and water resistance improvements. water-resistant agents, phenolic resins, surfactants, and conventionally used waxes. , metal salts of higher fatty acids, etc. can be added. It also promotes color development as needed. A thermofusible substance may be added to increase the temperature.

[0013] The paint for forming a heat-sensitive recording layer of the present invention contains the above-mentioned leuco compound and an organic acid or its ester. Additives such as pigments and sensitivity adjusters added as needed are mixed at appropriate concentrations. ball mill, sanddog, etc. in an aqueous medium containing a binder such as polyvinyl alcohol. It is generally prepared by grinding and dispersing using a grinder. Each configuration It is advantageous in terms of color development efficiency to make the substance as fine as possible, and particles with a particle size of 3μ or less It is preferable to atomize the particles into small particles. The heat-sensitive paint obtained in this way is used as an ionomer as a support. - Coat it on the resin and dry it to obtain the heat-sensitive recording material of the present invention. Application of the above heat-sensitive paint , regular blade coater, air knife coater, bar coater, reverse roll coater This can be done by using -tar etc.

[0014] The overcoat layer has the same overcoat as conventional overcoat layers. Any agent can be used, such as PVA, modified PVA, starch, and casein. It can be formed using

[0015]

【Example】

The structure of the heat-sensitive label of the present invention formed using the above-mentioned materials is shown in FIG. That is, in FIG. 1, 1 is a support made of a transparent synthetic resin film, and 2 is the above-mentioned support. A colored adhesive layer was applied to the back side of the support, and 3 was attached to the adhesive layer. Release paper, 4 is a leuco compound formed on the surface side of the support and a color developer as coloring components. The contained heat-sensitive recording layer, 5, is for protecting the heat-sensitive recording layer or improving running performance of the thermal head. This is an overcoat layer.

[0016] The present invention will be explained in more detail with reference to manufacturing examples. Example 1 Support One side of a transparent biaxially stretched PP film with a thickness of 30 μm was subjected to corona discharge treatment, and Ionomer Emulsion Chemipearl S (manufactured by Mitsui Petrochemicals) was applied to the treated side to a solid content of 0. It was coated and dried to a weight of 2 g/m ² . Next, a paint for forming a heat-sensitive recording layer was prepared by dispersing liquids A and B having the following compositions in each paint shaker (manufactured by Toyo Seiki) for 10 hours. Solution A: Leuco dye 3-dibutylamino-6-methyl-7-anilinofluorane 5g Zinc stearate 5g Polyvinyl alcohol (12% solution) 40g Water 50g Solution B: Bisphenol A 10g Zinc stearate 3g Polyvinyl Alcohol (12% liquid) 40g Water 47g Next, 100g of liquid A, 100g of liquid B, 50g of polyvinyl alcohol (12% liquid), and 60g of water were mixed and stirred to make a coating liquid. The solution was applied to the ionomer layer of the support described above using a Mayer bar so that the coated amount after drying was 8 g/m ² , and then dried to obtain a heat-sensitive recording material. A colored adhesive layer consisting of styrene-butadiene rubber as an elastic body, polyterpene resin as a tackifier, and yellow chrome yellow as a coloring agent was provided on the opposite side of the support, and a release paper coated with a silicone resin was further provided on the backing paper. The paper pattern was pasted on to create the label of this invention. Example 2 A label of the present invention was produced in exactly the same manner as in Example 1, except that titanium oxide, which is a white pigment, was used in place of the chrome yellow colorant used in Example 1.

[0017] Printability test Insert the commercially available thermal head KFT-216-8 MPD I (Kyoseki Co., Ltd.) onto the label created as above. Printing power is 0.7w/dot.Pulse cycle is 5.0ms, pulse width is 0.3ms. Print and measure the density and background density of the resulting image using Macbeth Densitometer RD-914 However, when the dot reproducibility was visually judged, it was found that in the case of the present invention, the dot reproducibility was The printing performance is good, and the recorded printed image is different from the color of the adhesive layer. There is contrast from the beginning and it is easy to see.

[0018]

[Effect of the idea]

As described above, in the present invention, the support and the heat-sensitive recording layer themselves are coated with a colorant or kneaded. It does not involve coloring, but simply provides a colored adhesive layer on the back of the support. Therefore, it is easy to process and suitable for small-lot production of labels. and above By arbitrarily changing the coloring of the adhesive layer, you can easily create labels with different colors. It has the advantage that it can be made at low cost. This invention also has good recording properties because it uses a transparent synthetic resin film for the support. Furthermore, if the heat-sensitive recording layer or support is transparent, printing will not be possible, which is a problem with conventional methods. It is possible to solve the problem that it becomes difficult to see things that are displayed.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a heat-sensitive label of the present invention.

[Explanation of symbols]

1 Support 2 Adhesive layer 3 Release paper 4 Heat-sensitive recording layer 5 Overcoat layer

Claims (1)

[Scope of utility model registration request] Claim 1: A heat-sensitive label in which a release paper is attached to the back side of a support via an adhesive layer, and a heat-sensitive recording layer containing a leuco compound and a color developer as coloring components is provided on the surface of the support. A transparent film-based heat-sensitive label, characterized in that the adhesive layer is a colored adhesive layer, and the support is made of a transparent synthetic resin film.