JPH06127090A - Tape for printing and tape cassette containing the same tape - Google Patents

Abstract

PURPOSE:To provide a tape for printing in which the tape and characters printed on the tape are not deteriorated, not discolored even if it is exposed with an ultraviolet ray and a tape cassette containing the same tape. CONSTITUTION:An overcoating layer 1 containing ultraviolet ray absorbent dispersed therein is provided on a heat sensitizer layer 2 formed on one surface of a base material sheet 3. Thus, both a printed part and a nonprinted part of a tape T for printing are effectively protected against an ultraviolet ray to prevent the printed part from being faded as much as possible and to also prevent the nonprinted part from being discolored (yellowed). As a result, the tape T for printing in which characters, etc., are not deteriorated and which can be stably used for a long period is realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing tape used in a tape printing apparatus having a thermal head and a tape cassette containing the printing tape, and more particularly to a character capable of printing characters by being colored by the thermal head. Yes,
Further, the present invention relates to a printing tape which is not deteriorated or discolored by ultraviolet rays and can be provided with abrasion resistance to the characters and the like, and a tape cassette incorporating the printing tape.

[0002]

2. Description of the Related Art Conventionally, various tape printers have been proposed for printing characters and the like on a long printing tape.
In such a tape printer, in general, a tape cassette having a built-in printing tape is mounted on the main body of the apparatus, and the printing tape is pulled out from the tape cassette and a character is printed on the printing tape by a printing ribbon via a thermal head. A tape is created by printing the same, and the tape thus created is used by being attached to the back surface of a video cassette or the like.

This type of tape printer is roughly classified into the so-called non-laminating type and laminate type according to the printing method. Here, a non-laminating type tape printer is disclosed in, for example, European Patent Publication No. 272.
As disclosed in Japanese Laid-Open Patent Publication No. 232, a character or the like is printed by a thermal head on a non-adhesive surface of a printing tape composed of a single-sided adhesive tape with release paper, via a printing ribbon.
A laminate type tape printer is a type that does not protect the printing surface thereof, and has a see-through property as disclosed in, for example, Japanese Patent Application No. 62-199662 filed by the present applicant. It is a type in which characters and the like are printed on one surface of a printing tape made of a film tape by a thermal head through a printing ribbon, and a double-sided adhesive tape with release paper is attached to the printing surface. Of the two types, the non-laminated type, in particular, has the print surface of the printing tape not protected, so that characters and the like are easily peeled off and the abrasion resistance of the character and the like is low.

As described above, in any of the above types of tape printers, when a character or the like is printed on the printing tape, the printing is performed by using the printing ribbon.

[0005]

However, the printing tape used in the above-mentioned conventional tape printing apparatus generally does not consider deterioration or discoloration of the tape due to ultraviolet rays. Had a problem of deterioration and discoloration (yellowing) due to exposure to ultraviolet rays for a long period of time. In this case, in a conventional tape printer that prints characters and the like on the printing tape via the printing ribbon, the ink component of the printing ribbon is mainly composed of carbon-containing wax, and the ink is exposed to ultraviolet rays. On the other hand, although it does not easily deteriorate or discolor, the printing tape itself easily deteriorates and discolors when exposed to ultraviolet rays, especially when the tape printer is used in a bright and sunny place. There is a possibility that the tape for use may turn yellow or fade in a short period of time.

Further, the printing tape and the printing ribbon used in the conventional tape printing apparatus are arranged in the same tape cassette while being wound around separate spools. It is necessary to control the traveling of both the print ribbon and the print ribbon independently to achieve matching between them. As described above, it is very difficult to control the running of the printing tape and the printing ribbon while pulling them out from the separate spools so as to match them.

Further, in particular, in the conventional non-laminating type tape printer, since the characters printed on the printing tape are not protected at all, the abrasion resistance of the characters is inevitably low. Will end up.

Further, as described above, the printing tape and the printing ribbon are arranged in the tape cassette while being wound on separate spools, respectively. Parts and the like are also required to make traveling smooth. Therefore, the number of parts to be housed in the tape cassette cannot be reduced, and it is difficult to reduce the size of the tape cassette and reduce the cost.

The present invention has been made to solve the above-mentioned problems of the prior art. Even when exposed to ultraviolet rays, the printing tape and the characters printed on the printing tape deteriorate or discolor. By providing a printing tape that does not require a printing ribbon and by eliminating the need for a printing ribbon, running control of the printing tape can be performed extremely easily.
In addition, it is an object of the present invention to provide a tape cassette which can print characters and the like with high abrasion resistance, reduce the number of parts, and have a low cost.

[0010]

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention is to attach a release paper via an adhesive layer formed by coating on one surface of a base material sheet, and to form a substrate on which an adhesive layer is formed. A printing tape comprising a heat-sensitive agent layer capable of forming a color by a heating element of a thermal head on the other surface of the material sheet, and an overcoat layer formed by dispersing an ultraviolet absorber on the heat-sensitive agent layer. The ultraviolet absorber is composed of a benzotriazole derivative.

Further, it has a cassette case and a tape spool rotatably arranged in the cassette case, and an adhesive layer formed by coating on one surface of the base sheet is provided around the tape spool. While attaching the release paper,
Printing with a heat-sensitive agent layer that is capable of coloring with a heating element of a thermal head formed on the other surface of the base material sheet on which an adhesive layer is formed, and an overcoat layer formed by dispersing an ultraviolet absorber on the heat-sensitive agent layer It is a tape cassette with a built-in printing tape wound with a printing tape.

Here, the heat-sensitive agent layer is a leuco dye, a color developer that causes a color development reaction with the leuco dye at the time of heat generation to develop the leuco dye, and a color development acceleration that promotes the color development reaction between these leuco dye and the color development agent. Agent, a binder for binding a leuco dye and a color developer, other pigments, auxiliaries and the like.

For example, the following leuco dyes can be applied to the heat-sensitive agent layer of the present invention. (A) Triphenylmethane dye 3,3-bis (P-dimethylaminophenyl) -phthalide, 3,3-bis (P-dimethylaminophenyl) -6
-Dimethylaminophthalide (also known as crystal violet lactone), 3,3-bis (P-dimethylaminophenyl) -6-chlorophthalide, 3,3-bis (P-dibutylaminophenyl) phthalide (also known as malachite green lactone). (B) Fluoran dyes 3-dimethylamino-6-methoxyfluorane, 3-dimethylamino-6-methyl-7-chlorofluorane, 3
-Dimethylamino-5-methyl-7-dibenzylaminofluorane, 3-diethylamino-7-chlorofluorane, 3-diethylamino-7-methoxyfluorane, 3
-Diethylamino-7-methylaminofluorane, 3-
Diethylamino-7-dibenzylaminofluorane, 3
-Diethylamino-7- (N-methylanilino) fluorane, 3-diethylamino-7-orthochloroanilinofluorane, 3-diethylamino-7,8 benzofluorane, 3-diethylamino-6-methyl-7-chlorofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7
-P-butylanilinofluorane, 3-diethylamino-5-methyl-7-dibenzylaminofluorane, 3-
Morpholino-5,6 benzofluorane, 3-ethyl-6
-Methyl-7-anilinofluorane, 2-anilino-6
-Diethylaminofluorane, 3- (N-methyl-N-
Cyclohexylamino) -6-methyl-7-anilinofluorane. (C) Phenothiazine dyes benzoyl leuco methylene blue, 2,2 dimethyl leuco methylene blue, P-anisoyl leuco methylene blue, N-bivalyl leuco methylene blue, (d) Rhodamine lactam dyes N-phenyl rhodamine β-lactam, adrodamine β-saltone. (E) Spiropyran dyes Benzo-β-naphthospiropyran, 1,3,3-trimethyl-6′-chloro-8′-methoxy-indolinobezospiropyran.

Further, a phenolic compound is used as the color developer, and the phenolic compound is liquefied or vaporized at room temperature or higher to react with the leuco dye to develop a color of the leuco dye. Examples of the phenolic compound include the following. 4,4'-isopropylidenediphenol (bisphenol A), 4,4 '
-Isopropylidene bis (2-chlorophenol),
4,4'-isopropylidene bis (2-methylphenol), 4,4'-isopropylidene bis (2-tert)
-Butylphenol), 4,4'-sec-butylidenephenol, 4,4'-cyclohexylidenephenol, 4-tert-butylphenol, 4-tert-
Octylphenol, 4-tert-octyl caracol, 4-phenylphenol (P-phenylphenol), 4-hydroxydiphenoxide, 2,2′-dihydroxydiphenol, α-naphthol, β-naphthol,
Methyl-4-hydroxybenzoate, benzyl-4-
Hydroxybenzoate, ethyl-4-hydroxybenzoate, propyl-4-hydroxybenzoate, 4
-Hydroxy-acetophenol, novolac type phenol resin, halogenated novolac type phenol resin, and other phenol polymers.

Further, as the color accelerating agent, stearic acid amide, stearic acid methylenebisamide, oleic acid amide, palmitic acid amide, macaroic oleic acid amide,
Palm fatty acid amide and the like are applicable.

Further, the following compounds can be applied as the binder. For example, polyvinyl alcohol, starch or its modified products and derivatives, methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, arabic gum, gelatin, casein, polyvinylpyrrolidone, polyacrylamide, polyacrylic acid salt, styrene / maleic anhydride copolymer, isobutylene / anhydrous. Examples include maleic acid copolymers, styrene / butadiene copolymers, polyvinyl acetate, polyacrylic acid esters and the like.

Others The heat-sensitive agent layer includes white pigments such as talc, clay, silica, titanium oxide and urea formalin resin,
Further, various waxes, higher fatty acid metal salts, higher fatty acid amides, dispersants, lubricants, defoaming agents and the like may be added.

Next, the overcoat layer protects the heat-sensitive agent layer, and examples of the compound forming the overcoat layer include polyvinyl alcohol, methyl cellulose, ethyl cellulose, carboxymethyl cellulose, povinylpyrrolidone, polyacrylamide, and the like. Starch, gelatin, methoxycellulose and the like are applicable.

The following compounds are applicable as the benzotriazole derivative dispersed in the overcoat layer. For example, 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- (3. 5-di-
t-butyl-2-hydroxyphenyl) benzotriazole, 2- (3-t-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2-
(3,5-di-t-butyl-2-hydroxyphenyl)
-5-chlorobenzotriazole, 2- (3,5-di-
Examples include t-amyl-2-hydroxyphenyl) benzotriazole and the like.

Further, the main purpose of the overcoat layer is to protect the heat-sensitive agent layer from moisture, so that the overcoat layer contains a waterproofing agent. Here, as the waterproofing agent, formalin, glyoxal, chromium alum, melamine, melamine formalin, polyamide resin, polyamide-epichlorohydrin resin and the like can be applied.

As the base sheet, a polyester film, a polyamide film, a polypropylene film, a plastic film such as a vinyl chloride film, high quality paper, Japanese paper, etc. are used. Further, as the adhesive, solvent-based acrylic adhesive, rubber adhesive, water-soluble adhesive,
Adhesives such as hot melt adhesives and emulsion adhesives are used. As the release paper, glassine paper or polyethylene terephthalate (PET) coated on one side with silicon is preferably used.

[0022]

In the present invention having the above-mentioned structure, the printing tape wound around the tape spool at the time of printing is pulled out to the outside of the cassette case, and characters or the like are printed on the printing tape via the thermal head. At this time, the heat-sensitive agent layer formed on the base material sheet is colored by the heating element of the thermal head, so that characters and the like are formed on the heat-sensitive agent layer. Here, since the heat-sensitive agent layer is protected by the overcoat layer,
The characters and the like formed on the heat-sensitive agent layer are not easily peeled off. Further, since the ultraviolet absorber is dispersed in the overcoat layer, even when the printing tape is exposed to ultraviolet rays, not only the characters and the like formed on the heat-sensitive agent layer but also the characters and the like are not printed. Can be reliably prevented from being deteriorated or discolored. Further, since the heat-sensitive agent layer itself can develop color through the heating element of the thermal head, and a printing ribbon is not required for forming characters, etc., the number of parts to be stored and arranged in the tape cassette is reduced. The structure of the tape cassette is simplified.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A detailed description will be given below of an embodiment embodying the present invention with reference to the drawings. First, the structure of the printing tape T housed in the tape cassette according to this embodiment will be described with reference to FIG. FIG. 1 is a cross-sectional view schematically showing the printing tape, and one surface of the base material sheet 3 (see FIG.
The release paper 5 is attached to the inner and lower surfaces via the adhesive layer 4. Further, the heat sensitive agent layer 2 is applied and formed on the other surface (upper surface in FIG. 1) of the base material sheet 3, and the overcoat layer 1 is further formed on the heat sensitive agent layer 2. An ultraviolet absorber is dispersed and contained in the overcoat layer. 1. Creation of Printing Tape Next, a method of creating the printing tape T configured as described above will be described. (1) Base Material Sheet As the base material sheet 3, a 38 μm-thick polyester film (Teijin Tetron S-38) was used. (2) Preparation of Heat Sensitive Paint For preparation of heat sensitive paint, first, A having the following composition
Prepare solutions and solutions B. (Solution A) 1. Leuco dye 3-diethylamino-6-methyl-7-anilinofluorane 5 g 2. Binder epoxy-modified polyvinyl alcohol 20% liquid 40 g 3. Water 100 g (solution B) 1. Developer bisphenol A 10 g 2. Coloring accelerator Amide stearate 7 g 3. Binder epoxy-modified polyvinyl alcohol 20% liquid 40 g 4. 100 g of water

After preparing the solutions A and B having the above-mentioned composition, the solutions A and B are separately dispersed by a ball mill, and 100 g of the solutions A and 100 g of the solutions B are mixed with 20% of epoxy-modified polyvinyl alcohol. 50 g and 50 g of water are added and mixed and stirred to prepare a heat-sensitive agent coating material. (3) Application of heat-sensitive agent coating The heat-sensitive agent coating prepared as described above is applied to one surface of the substrate sheet 3 so that the coating amount is 10 g / m ^2, and then dried to form the heat-sensitive agent layer 2. Form. (4) Formation of Overcoat Layer First, an overcoat agent liquid having the following composition is prepared. 1. Epoxy-modified polyvinyl alcohol 20% liquid 40 g 2. Ultraviolet absorber 2- (3-tert-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole 2 g 3. 100 g of water Next, the overcoat layer 1 was gravure-coated on the upper surface of the heat-sensitive agent layer 2 formed as described above so that the coating amount was 1 g / m ^2, and dried to form the overcoat layer 1. Form. (5) Preparation of Release Paper First, an adhesive having the following composition is prepared. (Adhesive) 1. Oil and fat (oil and fat AS-2050 manufactured by one company) 100 g 2. 2 g of oil and fat (oil and fat B-45 manufactured by one company) 3. Ethyl acetate 30g

After adjusting the pressure-sensitive adhesive by stirring and mixing the above components, the pressure-sensitive adhesive is adjusted to 20 g / m ² on the silicon-coated surface of the release paper 5 having a thickness of 60 μm and coated on one side with silicon. The pressure-sensitive adhesive layer 4 is formed by coating. (6) Preparation of printing tape The pressure-sensitive adhesive layer 4 of the release paper 5 prepared as described above is used as the base sheet 3 on which the heat-sensitive agent layer 2 and the overcoat layer 1 are formed.
Attach to the other side of. As a result, the printing tape T is created. 2. Preparation of Print Sample Next, a method of preparing a print sample using the printing tape T prepared as described above will be described with reference to FIGS. 2 and 3. FIG. 2 is a plan view of the lower cassette case excluding the upper cassette case of the tape cassette, and FIG. 3 is a perspective view of the tape printer.

First, the printing tape T is attached to the tape cassette C.
For mounting inside, the printing tape T produced as described above is cut into a width of 12 mm, and the release paper 5 is cut around the tape spool 10 (both the outer diameter and the height are formed to 12 mm). Wind it so that it is on the outside. The tape spool 10 is set in the lower cassette case 11 as shown in FIG. 2 (the tape spool 10 is rotatably held by the lower cassette case 11 and an upper cassette case (not shown)).

In the lower cassette case 11, the printing tape T is fed from the tape spool 10 to the tape guide portion 1.
The printing tape T is guided to the opening 13 via 2 and is fed by a tape feeding roller 14 which is fitted to a tape feeding shaft 21 of a tape printing device 20 described later to feed the printing tape T. To be Also, the opening 1
3, a thermal head 15 (which is fixed to a cassette mounting portion 22 of a tape printing device 20 described later, and is provided with a plurality of heating elements in the vertical direction) is arranged. A roller support member 16 (supported by the tape printer 20 so as to be rotatable around a shaft 19) is disposed opposite to the roller 15. A platen roller 17 and a pressure contact roller 18 are rotatably supported by the roller support member 16, and when the thermal head 15 prints characters on the printing tape T, the roller support member 16 is used. 16 is rotated about shaft 19 in a counterclockwise direction. As a result, the platen roller 17 is brought into pressure contact with the thermal head 15 so that characters and the like are reliably printed by the thermal head 15, and the pressure contact roller 18 is brought into pressure contact with the tape feed roller 14 and both rollers 1
The printing tape T after printing is sent to the outside of the tape cassette C by the cooperation of 8 and 14.

The tape cassette C is used as a printing device 20.
It is set in the tape mounting portion 22 provided on the rear side (see the right side in FIG. 3) (see FIG. 3). After this, the thermal head 1
By selectively energizing the heating element 5 to heat the heat-sensitive agent layer 2 from the overcoat layer 1 side of the printing tape T, a color-forming reaction occurs in the heat-sensitive agent layer 2 to generate a desired character or the like. Are formed in the heat sensitive agent layer 2.

The printing tape T on which the characters and the like are printed in this way is discharged to the outside of the tape cassette C by the cooperation of the tape feed roller 14 and the pressure contact roller 18. The discharged printing tape T is cut by a cutter, and the tape T is used as a printing sample. 3. Preparation of Comparative Print Sample Next, a comparative print sample was prepared for comparison with the print sample prepared as described above. Here, the comparative print sample was basically prepared by the same method as that of the above-mentioned print sample, and was different from the print sample in the overcoat layer 1 by using 2- (3-tert-butyl-5-methyl- The difference is that 2-hydroxyphenyl) -5-chlorobenzotriazole is not dispersed. 4. Comparison between Printed Sample and Comparative Printed Sample Regarding the effect produced by the presence or absence of the ultraviolet absorber in the overcoat layer 1, the printed part (character forming part) and the non-printing part (character forming part) in each printed sample are compared. A comparative examination was performed by measuring the optical density of the printing tape T other than the above). The measurement result of such optical density is shown in FIG.

FIG. 4 is a graph showing the measurement results, where the horizontal axis is the ultraviolet (UV) irradiation time and the vertical axis is the optical density. Here, the optical density was measured by applying an ultraviolet ray having a wavelength range of 300 nm to 400 nm to both print samples and a comparative print sample.
72 at a radiant intensity of 0 watt / square meter (W / m ² ).
This was performed by irradiating for a period of time and measuring the optical densities of the printed portion and the non-printed portion in each printed sample and comparative printed sample every 24 hours. In addition, the print density is measured by measuring the reflectance of each portion at every 5 nm in the visible light range (wavelength range of 400 to 700 nm) with a colorimeter (CM-2002 manufactured by Minolta Co., Ltd.), and measuring each reflectance. It was calculated by calculating the logarithm of the reciprocal and then calculating the average value of the calculated values. In FIG. 4, (Δ) is the optical density in the printed part of the printed sample, (+) is the optical density in the non-printed part of the printed sample, (⋄) is the optical density in the printed part of the comparative printed sample, (□). Indicates the optical density in the non-printed portion of the comparative sample.

In FIG. 4, first, when comparing the optical densities of the print portion of the print sample and the comparative print sample, the optical densities of the print portions of the print sample were 1.23 to 1. 01, and the density difference is only 0.22, whereas the optical density in the print portion of the comparative print sample is 1.23.
It can be seen that the density difference has reached 0.37 after changing from 0.86 to 0.86. This is because the ultraviolet absorber is not dispersed and contained in the overcoat layer 1 in the printing tape T of the comparative print sample, so that the fading is caused in the color-developed portion of the characters and the like formed on the heat-sensitive agent layer 2 by the ultraviolet irradiation. It is considered to be caused by the occurrence. On the other hand, although a slight fading phenomenon occurs also in the printed portion of the printed sample, since the ultraviolet absorber is dispersed and contained in the overcoat layer 1 of the printing tape T of the printed sample, the fading phenomenon is comparatively printed. It is not so remarkable as compared with the case of the sample.

Next, comparing the optical densities of the non-printed portions of the printed sample and the comparative printed sample, the optical densities of the non-printed portion of the printed sample are 0.08 to 0.18 during 72 hours of ultraviolet irradiation. The optical density in the non-printed portion of the comparative print sample is similarly 0.08 to 0.30.
It can be seen that the concentration difference changes to 0.22. This is because the overcoat layer 1 in the printing tape T of the comparative print sample does not contain the ultraviolet absorber dispersed and contained as in the above, so that the non-printed portion is discolored (yellowed to yellow) by the irradiation of ultraviolet rays. It is thought that this is due to what was done. On the other hand, although a slight discoloration phenomenon is observed even in the non-printed portion of the printed sample, since the ultraviolet absorber is dispersed and contained in the overcoat layer 1 in the printing tape T of the printed sample, the discoloration phenomenon is caused. It is not so remarkable as compared with the comparative print sample.

As described above, the ultraviolet absorbent dispersed and contained in the overcoat layer 1 of the printing tape T in the printed sample is not only printed but not printed (the colored portion formed in the heat sensitive agent layer 2). It also has an effect of effectively protecting the part (the part which is not colored in the heat sensitive agent layer 2) from ultraviolet rays.

As described in detail above, in the printing tape T according to this embodiment, the overcoat layer 1 in which the ultraviolet absorber is dispersed and contained is formed on the heat sensitive agent layer 2 formed on one surface of the base sheet 3. Since the print tape T is provided, both the printing portion and the non-printing portion of the printing tape T can be effectively protected from ultraviolet rays. As a result, it is possible to prevent discoloration in the printed area as much as possible and also prevent discoloration (yellowing) in the non-printed area, so that the characters can be used stably for a long period without deterioration. It is possible to realize a possible printing tape T.

In the tape cassette C according to this embodiment, the heat sensitive agent layer 2 and the overcoat layer 1 are formed on one surface of the base material sheet 3, and the adhesive layer 4 is interposed on the other surface of the base material sheet 3. Since the printing tape T to which the release paper 5 is attached is incorporated, the printing ribbon and the member for running the printing ribbon in the tape cassette C can be completely eliminated. This simplifies the structure of the tape cassette C, so that the printing tape T can be stably and smoothly run without being obstructed, and the number of parts for forming the tape cassette C is reduced. It is possible to reduce the number of tape cassettes and reduce the cost. Further, by forming the overcoat layer 1 on the upper surface of the heat-sensitive material layer 2, it is possible to significantly improve the abrasion resistance of characters and the like printed on the printing tape T, and printing with high robustness. The tape T for use can be created.

The present invention is not limited to the above-mentioned embodiments, and it goes without saying that various improvements and modifications can be made without departing from the gist of the present invention.

For example, in the above embodiment, the ultraviolet absorber is dispersed and contained in the overcoat layer 1.
It is easily conceivable that the same effect as described above can be obtained even when dispersed and contained in the heat-sensitive agent layer 2. Further, it is necessary to form an ultraviolet absorber layer on the heat-sensitive agent layer 2. You may

[0038]

INDUSTRIAL APPLICABILITY As described above, the present invention provides a printing tape and a printing tape in which characters printed on the printing tape are not deteriorated or discolored even when exposed to ultraviolet rays. By eliminating the need for a printing ribbon, it is possible to control the running of the printing tape very easily and to print characters with high wear resistance, thus reducing the number of parts and reducing costs. It is possible to provide a tape cassette having a low cost, and the effect produced by the tape cassette is great.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing a printing tape T.

FIG. 2 is a plan view of a lower cassette case excluding an upper cassette case of the tape cassette.

FIG. 3 is a perspective view of a tape printer.

FIG. 4 is a graph showing measurement results of optical densities of a printed portion and a non-printed portion in a printed sample and a comparative printed sample.

[Explanation of symbols]

 1 Overcoat Layer 2 Heat Sensitive Material Layer 3 Base Material Sheet 4 Adhesive Material Layer 5 Release Paper 10 Tape Spool 11 Lower Cassette Case 15 Thermal Head C Tape Cassette T Printing Tape

Claims (3)

[Claims] 1. A release paper can be attached via an adhesive layer formed by coating on one surface of a base sheet, and color can be developed by a heating element of a thermal head on the other surface of the base sheet on which the adhesive layer is formed. A printing tape, comprising: a heat-sensitive agent layer formed on the heat-sensitive agent layer; and an overcoat layer formed by dispersing an ultraviolet absorber on the heat-sensitive agent layer. 2. The printing tape according to claim 1, wherein the ultraviolet absorber comprises a benzotriazole derivative. 3. A cassette case, and a tape spool rotatably disposed in the cassette case, and an adhesive layer formed by coating on one surface of the base sheet around the tape spool. A release paper is attached, and a heat-sensitive agent layer capable of developing color by a heating element of a thermal head is formed on the other surface of the base material sheet on which the pressure-sensitive adhesive layer is formed, and an ultraviolet absorber is dispersed on the heat-sensitive agent layer. A tape cassette containing a printing tape, characterized in that a printing tape provided with an overcoat layer is wound.