JPH04276493A - Re-transfer sheet for preparing dry transfer material - Google Patents

Abstract

PURPOSE:To obtain a re-transfer sheet not transferring a circumferential unnecessary surface treatment agent at the time of re-transfer by using a specific surface treatment agent having specific tensile force and a specific m.p., softening point or melt viscosity. CONSTITUTION:A re-transfer sheet 10 is obtained by forming a surface treatment agent layer 12 to one surface of a base material 11. The surface treatment agent layer 12 desirably has tensile force of 1-100kg/cm<2>. Further, the m.p. and softening point of a surface treatment agent are desirably 100 deg.C or higher and it is desirable that the viscosity thereof is 100 poise or more in a molten state. By using this surface treatment agent having the above mentioned tensile force and m.p., only the surface treatment agent at the part superposed on the ink image 13 formed to the re-transfer sheet 10 is transferred as an image 13 at the time of re-transfer and no circumferential unnecessary surface treatment agent is transferred.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to retransfer of a dry transfer material for forming the above-mentioned characters, symbols, figures, etc. on the surface of a transferred object by pressure-sensitive transfer of images such as letters, symbols, figures, etc. Sea
In particular, the present invention relates to a retransfer sheet in a dry transfer material produced by printing and thermal transfer using a printing device such as a thermal transfer printer, typewriter, or word processor.

0002

2. Description of the Related Art Conventionally, there is a technique related to a basic sheet capable of producing a dry transfer material by a thermal transfer method, as disclosed in Japanese Patent Application Laid-Open No. 128987/1987.

[0003] In this report, a film of polyethylene, polypropylene, fluororesin, etc. having a smooth surface with a contact angle of at least 95° to water, paper,
A sheet is used in which a coating layer made of silicone resin is formed on the surface of a metal foil or plastic film base material.

In order to form an ink image by thermal transfer onto a sheet having a contact angle of 95° or more (particularly 105° or more), it is necessary to reduce the surface tension of the ink to form an ink image on the sheet.
The temperature of the ink needs to be raised because the adhesive force between the sheet and the ink must be greater than the cohesive force between the ink and the adhesive force between the ink and the PET substrate. . Therefore, in order to achieve this, high printing energy is required, which is extremely disadvantageous for thermal transfer devices in terms of durability of the head, load on the power supply, etc.

[0005] Furthermore, since an image formed by thermal transfer on a surface with poor wettability has weak adhesion to the surface, it will be retransferred even if only a small amount of pressure is applied. Therefore, unnecessary images are also transferred again, causing stains. Moreover, there is also the problem that the image may come off even if touched slightly during handling.

Furthermore, since the coefficient of static friction on the surface of the sheet is extremely small, there is a problem in that the sheet moves easily and is difficult to fix when a thermally transferred ink image is retransferred. Therefore, the retransferred image may be misaligned or distorted, making it impossible to obtain a complete image.

By the way, in order to prevent the problem of sheet movement during pressure-sensitive retransfer, Japanese Patent Laid-Open No. 63-24
Japanese Patent No. 6298 discloses a technique in which an adhesive layer is provided on a sheet separately from a transfer pattern.

[0008] However, partially providing this adhesive layer at a predetermined position requires ingenuity in manufacturing and requires the use of a dedicated device, resulting in a large cost. Furthermore, in order to cover the adhesive surface until use, release paper or the like must be attached, which further requires device innovation and cost. Furthermore, for sheets provided with a peelable coating layer made of silicone resin, it is necessary to apply two types of coating, the coating layer and the adhesive layer, and it does not matter which one is applied first. There is a good chance that it will affect the coating later. In other words, if the silicone is applied first, it will cause splatter when applying the adhesive, and on the other hand, if the adhesive is applied first, it will become sticky and difficult to apply, and in order to prevent this stickiness, it will be difficult to apply the adhesive. Even if a paper pattern is attached, coating will still be difficult due to its thickness. Even if it is successfully manufactured, the adhesive layer is only present in a portion of the image, so the entire area around the image is not fixed, so the sheet will still move and it will not be possible to form a perfect image. It's difficult.

In any case, the surface treatment agents for retransfer sheets that have been reported so far are not agents that retransfer along with the ink image from the sheet substrate, but rather This improved the releasability from the ink image. Therefore, it was necessary to reduce the wettability of the surface and weaken the adhesion between the ink image and the retransfer sheet. For this reason, various problems have arisen, such as poor thermal transfer properties, the need for a large amount of transfer energy, and poor abrasion resistance.

[0010] In order to solve the above-mentioned problems, the present applicants have proposed a technology for transferring the entire surface treatment agent as described in Japanese Patent Laid-Open No.
This method has already been proposed in JP-A No. 81684 and Japanese Patent Application Laid-Open No. 2-88294.

[0011] The surface treatment agent described in the above application has a tensile strength of 1 Kg/cm2 or more and 100 Kg/cm2.
In the following, those having a melting point or softening point of 100° C. or higher, or a melt viscosity at 100° C. of 1000 poise or higher are used.

0012

[Problems to be Solved by the Invention] However, when performing a retransfer operation using a retransfer sheet of the above-mentioned transfer type surface treatment agent, the ink image formed on the retransfer sheet is
There is a possibility that the surrounding surface treatment agent may also be transferred. For this reason, if the surface treatment agent is colorless and transparent, there is not much of a problem, but if a coloring agent is added to the surface treatment agent,
The lines of the image formed by pressure-sensitive retransfer become extremely thick, or in severe cases, the image becomes crushed, making it difficult to visually recognize the existence of the image.

The present invention has been made to solve the above-mentioned problems, and its first purpose is to remove the portions that overlap the image formed on the transfer sheet during retransfer. It is an object of the present invention to provide a retransfer sheet in which only the surface treatment agent is transferred together with the image, and the surrounding excess surface treatment agent is not transferred.

[0014] A second object of the present invention is to provide a retransfer sheet that facilitates fixing of the sheet during retransfer and is difficult to move.

A third object of the present invention is to provide a retransfer sheet in which the ink image on the retransfer sheet does not peel off due to slight pressure or abrasion.

Furthermore, a fourth object of the present invention is to provide a retransfer sheet that can obtain good transfer quality with low transfer energy.

A fifth object of the present invention is to provide a retransfer sheet on which a transferred ink image can be completely retransferred without residual ink.

A sixth object of the present invention is to provide a retransfer sheet with which it is easy to check whether an ink image has been retransferred.

Furthermore, a seventh object of the present invention is to provide a retransfer sheet that can improve the scratch resistance of retransferred ink images.
The aim is to provide the following.

[0020]

[Means for Solving the Problems] In order to achieve this object, the retransfer sheet of the present invention contains a surface treatment agent of 1 kg/cm
It is characterized by having a tensile strength of not less than m2 and not more than 100 Kg/cm2, and by adding fine polyethylene powder.

[0021] Also, the above surface treatment agent is heated at 100°C.
Melting point or softening point higher than 100℃
By using a surface treatment agent having a melt viscosity of 1000 poise or more, the objective can be advantageously achieved.

[0022]

[Operation] The retransfer sheet of the present invention having the above structure has the following features:
For example, as shown in FIG. 1, a surface treatment agent layer 12 is formed on one surface of a base material 11.

It is desirable that the base material 11 has a thickness of 25 to 200 μm, preferably 50 to 150 μm. While it has sufficient mechanical strength for manufacturing and handling, it is designed so that pressure is easily applied during pressure-sensitive retransfer.
Further, it is desirable that the material has a certain degree of flexibility so that it is easy to manufacture a dry transfer material using thermal transfer.

However, if the elongation is too large, the base material will be elongated when pressure is applied during retransfer, resulting in distortion of the image, so a film having an elongation of 200% or less is preferable.

[0025] Furthermore, in order to accurately retransfer the image onto the transfer object during pressure-sensitive retransfer, the base material is preferably transparent or semi-transparent, and in particular, it is preferable that the heat-sensitive transfer image is completely retransferred. It is desirable that the sheet be semi-transparent so that it can be easily checked.

[0026] Plastic films, paper, metal foils, etc. are generally used as base materials having such characteristics. Examples of plastic films include fluorine-based films made of fluororesins such as ethylene, polypropylene, ethylene-tetrafluoroethylene copolymers and tetrafluoroethylene-hexafluoroethylene copolymers, polyethylene terephthalate, nylon, polyimide, Examples include polyvinyl chloride, polycarbonate, polysulfone, ethylene-vinyl acetate copolymer, acrylonitrile-butadiene-styrene copolymer, and ionomer.

Next, the surface treatment agent layer 12 formed on one surface of the base material 11 has a tensile strength of 1 Kg/cm2 or more and 100
It is desirable that it is below Kg/cm2.

This is necessary in order to retransfer the surface treatment agent together with the transfer image formed by thermal transfer from the sheet onto the object to be transferred. In other words, if the tensile strength is 100 Kg/cm2 or more, the cohesive force of the surface treatment agent is too large and forms a strong film, causing the problem that it will not transfer even if pressure is applied, and if the tensile strength is 1 Kg/cm2 or less, However, since the strength of the membrane is too weak, there is a problem that the sheet peels off just by bending, so a tensile strength of 1 Kg/cm2 or more and 100 Kg/cm2 or less is desirable.

[0029] Furthermore, the melting point and softening point of the above surface treatment agent are as follows:
It is desirable that the temperature is 100°C or higher, and even when melted, the temperature is 100°C or higher.
It is desirable that the viscosity at °C is 1000 poise or more.

[0030] This is because if a surface treatment agent that melts or becomes extremely soft at temperatures below 100°C is used, the surface treatment agent will also melt during image formation by thermal transfer, causing the sheet base material and the surface treatment agent to melt. This is because the adhesion force with the toner is improved, leading to poor retransfer.

By using a surface treatment agent having the above-mentioned tensile strength and melting point, an ink image formed by thermal transfer can be retransferred together with the surface treatment agent.
There is no need to consider the wettability of the surface treatment agent at all. Therefore, a good heat-sensitive transfer image can be obtained with low energy, and a retransfer sheet with good abrasion resistance and high adhesion between the ink image and the surface treatment agent can be obtained. Furthermore, since the coefficient of static friction on the surface can be increased, there is almost no movement of the sheet during retransfer, and a retransferred image can be easily and neatly formed.

Furthermore, until now, when transferring a large image using a thermal transfer device, in the case of a serial type with a small head,
It was necessary to form the image several times, and it had to be transferred overlappingly. Therefore, there is a problem in that the previously transferred image is scraped off by the head during the next transfer, and a complete image cannot be formed. Therefore, by dividing the image into rows and transferring them separately, the image was prevented from being scraped by the head, and when retransferring, the divided images were combined one after another to complete the retransferred image. If the sheet of the present invention is used, the adhesion force is increased, so that it becomes possible to thermally transfer large images in a connected state.

Another advantage of retransferring the entire surface treatment agent is that since the surface treatment agent is also retransferred together with the ink image, a complete retransferred image can be formed without any residual ink; In addition, the surface treatment agent retransferred together acts as a protective layer for the ink image, improving the scratch resistance of the retransferred image.

However, if the entire surface treatment agent is transferred, there is a possibility that the surface treatment agent around the ink image formed on the retransfer sheet may also be transferred. However, by adding polyethylene fine powder to the surface treatment agent, it is possible to change the adhesion, adhesion, and adhesion of the surface treatment agent layer, and by adjusting the amount added, the surface treatment agent layer can be changed. It is also possible to adjust the adhesion, adhesion, adhesion, etc. This makes it possible to lower the surface of the surface treatment agent layer to the desired level of adhesion, adhesion, and adhesion, and prevent transfer of excess surface treatment agent present around the image. be.

[0035] Furthermore, when a silicone compound is used,
In order to cure, a curing time of 30 seconds or more is required at a high temperature of 100°C or higher, but if polyethylene fine powder is used, it can be dried within 30 seconds at a temperature of 100°C or lower, so it can be cured at low cost and in a short time. This makes it possible to manufacture retransfer sheets and reduces manufacturing problems.

Furthermore, with surface treatment agents containing silicone compounds or fluorine compounds, it is difficult to clean the equipment and equipment used during coating, and at the same time, if the surface treatment agent is left unrolled without being sufficiently dried. , set-off is likely to occur. On the other hand, surface treatment agents containing fine polyethylene powder are easy to clean the equipment and equipment used, and at the same time,
This means that insufficient drying and set-off are less likely to occur. Furthermore, unlike silicone compounds and fluorine compounds, polyethylene fine powder can be dispersed well without considering solubility in solvents or compatibility with other resins, waxes, etc. This is extremely advantageous in selecting materials for processing agents and in manufacturing.

Examples of the above-mentioned surface treatment agents include polyethylene, ethylene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, celluloses, and ethylene-ethyl acrylate. Examples include resins such as copolymers, ethylene-acrylic acid copolymers, ionomers, ethylene-methacrylic acid copolymers, polyvinyl alcohol, and polyvinylpyrrolidone. Then, fine polyethylene powder is added to one type or a mixture of two or more of these resins.

In addition, in order to finely adjust the tensile strength of the surface treatment agent, increase the range of selection of materials used, and improve retransferability, polyethylene wax, montan wax, Fischer-Tropsch wax, synthetic wax,
Adding one or more waxes such as
It may be used as a complete replacement for resin. Furthermore, by adding dyes, pigments, etc., it is possible to obtain sufficient hiding power even if a color with weak hiding power is used.

If this resin is used as a main component, the tensile strength will become too large if it is dissolved in a solvent or used as a hot melt, so it should be used as a fine dispersion in emulsions, suspensions, etc. It's better to do so. In addition, fillers may be added to adjust tensile strength and adhesive strength.

By providing such a surface treatment agent on the sheet, thermal transferability, retransferability, scratch resistance, adhesion of the image during handling, fixation of the sheet during retransfer, It is possible to obtain a retransfer sheet with good confirmation of retransfer and scratch resistance of the retransfer image.

[0041] The ink ribbon used to thermally transfer the desired transfer image onto the retransfer sheet can be used in printing devices such as ordinary thermal transfer printers, typewriters, word processors, etc. There is no problem even if the ink is coated with wax-based ink.
In particular, it is desirable to use an ink ribbon having a two-layer structure consisting of a transferability adjustment layer and an ink layer, which further improves heat-sensitive transferability and pressure-sensitive retransferability. This transferability adjustment layer is provided on the ink layer as a top coat layer, and has higher heat-sensitive adhesiveness, hardness, viscosity, and cohesive force than the ink layer, and thereby improves wettability. bad retransfer sheet
The heat-sensitive transfer properties onto the paper are significantly improved, and pressure-sensitive re-transfer is also possible. Moreover, by providing the ink layer with pressure-sensitive adhesive properties, the pressure-sensitive retransferability becomes even better.

[0042]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment embodying the present invention will be described below with reference to the drawings, but it goes without saying that the present invention is not limited in any way by such description.

[0043] In addition to the following examples and the above-described specific description, the present invention may include various modifications based on the knowledge of those skilled in the art, as long as they do not depart from the spirit of the present invention. It should be understood that modifications, improvements, etc. may be made.

Example 1 A surface treatment agent having the following composition was coated on a polyethylene terephthalate film having a thickness of 50 μm, and then dried to give a contact angle with water of 39° and a coefficient of static friction of 0. A retransfer sheet having a size of about 42 and having a smooth surface was obtained. The tensile strength of this surface treatment agent is about 20 kg/cm2, and the melt viscosity at 150 DEG C. is about 2000 to 4000 poise.

Surface treatment agent composition
Weight part
polyethylene
...80 [Chemipearl M-200 manufactured by Mitsui Petrochemical Industries, Ltd.] Titanium oxide
・・・・・・ 20 [Tiepeke A-100 manufactured by Ishihara Sangyo Co., Ltd.] Polyethylene fine powder ・・・・・・
0.01 [Steel Chemical Industry Co., Ltd.
Flow Beads LE-1080 manufactured by Manufacturer Co., Ltd.] On the retransfer sheet thus obtained, a thermal transfer type tape writer (
The white ink was thermally transferred using P-touch (manufactured by Brother Industries, Ltd.) to obtain a dry transfer material having a desired transferred image. In this case, energy can be reduced compared to the conventional method, and a good transferred image can be obtained. When we performed pressure-sensitive retransfer onto transfer objects such as paper and plastic using this obtained dry transfer material, we found that it had sufficient hiding power and removed excess surface treatment agent around the ink image. It was possible to obtain a good white retransferred image with no transferred portions. Furthermore, since the sheet moves less and can be retransferred while being fixed, it has the advantage that it is easy to obtain a good retransferred image. In addition, since the surface treatment agent is also retransferred, it is easy to confirm whether the ink image has been retransferred.Since the surface treatment agent covers the retransferred ink image, the scratch resistance of the retransferred image is also improved. It got better.

Comparative Example 1 A dry transfer material was produced in the same manner as in Example using the transfer sheet of Example 1 without the addition of polyethylene fine powder to the surface treatment agent, and the material was reprinted on the transferred object. When a transferred image was formed by pressure-sensitive retransfer, excess surface treatment agent around the ink image was transferred, resulting in thick lines in the transferred printed image, making it difficult to confirm details.

[0047]

[Effect of the invention] As is clear from the detailed description above,
According to the present invention, when a dry transfer material is produced using a printing device such as a thermal transfer printer, typewriter, word processor, etc., a retransfer sheet to be printed is printed according to the present invention. , 1Kg/cm2 or more, 100K
g/cm2 or less, a melting point or softening point of 100°C or higher, or a melt viscosity of 1000°C at 100°C.
By using a surface treatment agent with a poise or higher, a retransfer sheet can be manufactured without considering wettability, so that a good transferred image can be formed with low energy. In addition, since the adhesive force is increased, the scratch resistance is improved, and
Depending on the amount of polyethylene fine powder added, adhesion, adhesion,
It is possible to adjust the adhesive strength, etc., so the sheet size during retransfer can be adjusted.
Easy to fix, only the surface treatment agent that overlaps the image formed on the transfer sheet is transferred together with the ink image, and excess surface treatment agent around the area is not transferred. This makes it possible to obtain a transfer sheet. In addition,
Since drying can be done at low temperatures and in a short time, manufacturing problems are also reduced. Furthermore, since the surface treatment agent is also retransferred, it is easy to confirm whether retransfer has been performed, and the retransfer quality is also extremely good. Moreover, the re-transferred surface treatment agent covers the image and forms a protective layer.
The scratch resistance of the retransferred image is also significantly improved.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view showing an example of a retransfer sheet according to the present invention.

[Explanation of symbols]

10 Retransfer sheet 11 Sheet base material 12 Surface treatment agent 13 Ink image

Claims (3)

[Claims] Claim 1: In a retransfer sheet for producing a dry transfer material produced by a thermal transfer method, the tensile strength of the surface treatment agent formed on one side of the sheet is 1 kg.
/cm2 or more and 100Kg/cm2 or less, and contains polyethylene fine powder. 2. The surface treatment agent has a melting point or softening point of 100°C or higher, or a melt viscosity of 10°C at 100°C.
2. The retransfer sheet according to claim 1, wherein the retransfer sheet has a poise of 00 poise or more. 3. The retransfer sheet according to claim 1, wherein the surface treatment agent is formed using a finely dispersed material such as an emulsion.