JPH0281685A - Retransfer sheet - Google Patents

Abstract

PURPOSE:To enable a transfer image printed on a good wettable surface to be excellently retransferred by a method wherein a finishing agent which has an elongation of 100% or over and contains polyethylene fine powder is used on a retransfer sheet to be printed. CONSTITUTION:A finishing agent layer 12 has an elongation of 100% or over and contains polyethylene fine powder in composition. Since a finishing agent is thus unilaterally elongated by pressurizing in retransfer time, adhesion between the finishing agent layer 12 and an image 13 weakens. The finishing agent layer 12 contains one kind or two or more kinds of mixtures of polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl-acrylate copolymer, ethylene-acrylate copolymer, etc. as a main component. Since wettability of the finishing agent becomes 80 deg. or under and a retransfer property is deteriorated in the case where a good wettable material (a contact angle to water of 80 deg. or under) is used in order to give elongation, the contact angle to water is taken as 80-120 deg. by adding polyethylene fine powder into composition of the finishing agent layer 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention applies pressure-sensitive transfer of an image of a character, symbol, figure, etc. onto the surface of an object to be transferred.

It relates to retransfer sheets of dry transfer materials that form figures, etc., and is particularly printed by printing devices such as thermal transfer printers, typewriters, and word processors.

The present invention relates to a retransfer sheet in a dry transfer material produced by thermal transfer.

[Prior Art] A report on a basic sheet capable of producing a dry transfer material using a thermal transfer method was published in Japanese Patent Application Laid-Open No. 128987/1987.
It has been made into a number.

In this report, a coating layer made of silicone resin is applied to the surface of a film made of polyethylene, polypropylene, fluororesin, etc. that has a smooth surface with a contact angle of at least 95° to water, or of paper, metal foil, or plastic film. A sheet formed with this is used.

[Problems to be Solved by the Invention] In order to form an image on a sheet having a contact angle of 95° or more (particularly 105° or more) by thermal transfer,
In addition to reducing the surface tension of the ink and making it wet onto the sheet, the adhesive force between the sheet and the ink must be greater than the cohesive force between the inks and the adhesive force between the ink and the polyethylene terephthalate (PET) base material. , it is necessary to raise the ink temperature. 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.

In addition, images formed on surfaces with poor wettability by thermal transfer are
Because the adhesion to several surfaces is weak, even a small amount of pressure will result in retransfer.

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 Application No. 1983-80127 reports that an adhesive layer is provided on the sheet separately from the transferred pattern. .

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, a release paper or the like must be attached, which further requires device innovation and cost.

Furthermore, for sheets with a releasable coating layer made of silicone resin, it is necessary to apply two types of coating, the coating layer and the adhesive layer, and whichever is applied first, it is necessary to apply the coating afterwards. There is a good chance that it will have an impact when In other words, if the silicone is applied first, it will cause splatter when applying the adhesive.On the other hand, if the adhesive is applied first, it will become sticky and difficult to apply, so release paper is used to prevent this stickiness. Even if it is applied, it will still be difficult to coat due to its thickness. Even if it were successfully manufactured, since the adhesive layer is only present in a part of the image, the entire area around the image is not fixed, so the sheet will still move and it will be difficult to form a perfect image. be.

Therefore, the present invention was developed against the background of such circumstances, and its first purpose is to provide a retransfer sheet that facilitates fixing of the sheet during retransfer and prevents movement. be.

A second 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 third object of the present invention is to provide a retransfer sheet that can obtain good transfer quality with low transfer energy.

Furthermore, a fourth object of the present invention is to provide a retransfer sheet that provides good retransfer quality even though the adhesive force between the ink image and the retransfer sheet is increased compared to conventional ones. It's about doing.

The fifth object of the present invention is to provide a retransfer sheet that can provide good retransfer quality even when a material with good wettability (contact angle with water of 80" or less) is used in the surface treatment agent composition. It is about providing.

Furthermore, the sixth object of the present invention is to provide a retransfer sheet having a surface treatment agent whose wettability can be adjusted so that good retransfer quality can be obtained even if the energy applied during thermal transfer is changed. Our goal is to provide the following.

A seventh object of the present invention is to provide a retransfer sheet having a surface treatment agent that can easily form a dry thin film by drying at low temperature and in a short time.

A further object of the present invention is to provide a retransfer sheet having a surface treatment agent that allows easy cleaning of the equipment used during production and coating of the surface treatment agent, and does not affect other surfaces such as set-off. There is a particular thing.

Furthermore, the ninth object of the present invention is to improve solubility, compatibility, etc.
The present invention has a surface treatment agent that can achieve the above objectives without considering compatibility with other surface treatment agent compositions.

[Means for Solving the Problems j] In order to achieve this object, the present invention is characterized in that the surface treatment agent for the retransfer sheet has an elongation of 100% or more, and furthermore, fine polyethylene powder is added. That is. Further, the objective can be advantageously achieved by imparting a static friction coefficient of 0.25 or more and a contact angle of 80 to 120'' to the surface treatment agent.

(Specific structure/effect) The retransfer sheet 10 according to the present invention has a surface treatment agent layer 1 on one surface of a base material 11, for example, as shown in FIG.
By forming 2.

The base material 11 has a thickness of 25 to 200 μm, preferably 5
It is desirable to have a thickness of 0 to 150 μm. While having sufficient mechanical strength for manufacturing and handling,
It is desirable to have a certain degree of flexibility so that pressure can be easily applied during pressure-sensitive retransfer, and so that a dry transfer agent can be easily manufactured by heat-sensitive transfer.

However, if the elongation is too large, the base material 11 will be elongated by applying pressure during retransfer, and the ink image 13 will be elongated.
Since distortion occurs in the film, a film having an elongation of 200% or less is preferable.

Further, the base material 11 is preferably transparent or semi-transparent so that the ink image 13 can be accurately retransferred onto the transfer object during pressure-sensitive retransfer, and in particular, the heat-sensitive transfer image can be completely retransferred. It is desirable that the sheet be semi-transparent so that it can be easily checked.

As the base material 11 having such characteristics, plastic film, paper, metal foil, etc. are generally used. 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 borisulfone, 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 surface static friction coefficient of 0.25 or more, preferably 0.3.
The above is desirable.

This is necessary in order to fix the sheet so that it does not move and become misaligned when retransferring the ink image 13 from the sheet onto the object to be transferred, so that a complete retransferred image can be formed.

In addition, the contact angle with water is 80 to 120", preferably 80".
By setting the angle to 110°, it is possible to increase the adhesion force between the ink image 13 and the retransfer sheet, so that unnecessary portions are not retransferred even with a slight presser pressure. Moreover, since it does not easily peel off even when rubbed, it becomes easy to handle.

Furthermore, until now, when a large image was transferred using a thermal transfer device, if the head was a small serial type, it was necessary to form the image several times, and the images had to be transferred one after the other. 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 is prevented from being scraped by the head, and when retransferring, the divided images are 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.

Since the wettability is improved and the adhesion force is increased, it becomes possible to form a thermal transfer image with low thermal transfer energy, and the quality thereof becomes good.

Furthermore, it is desirable that this surface treatment agent has an elongation of 100% or more. As a result, the surface treatment agent is stretched unilaterally by applying pressure during retransfer, and the adhesion between the surface treatment agent and the image becomes weak. So 1. Even if a surface treatment agent has good wettability and strong adhesion, retransferability will be good.

Examples of the above-mentioned surface treatment agents include polyethylene, ethylene-vinyl acetate copolymer, and ethylene-ethyl acrylate copolymer.

One or two of ethylene-acrylic acid copolymer, ionomer ethylene-methacrylic acid copolymer, silicone, etc.
Examples include those whose main component is a mixture of more than one species.

However, here, in order to provide elongation and for manufacturing advantages, materials with good wettability (contact angle with water of 80
'' or less), the wettability of the surface treatment agent is 80
'' or less, resulting in poor retransferability.Also, if the energy applied during thermal transfer to form an image on the retransfer sheet is increased, the adhesion between the ink image and the surface treatment agent becomes too strong. After all, retransferability deteriorates.

Therefore, by adding polyethylene fine powder to the composition of the above surface treatment agent, the contact angle with water is 80 to 120.
By achieving ' and adjusting the amount added,
This makes it possible to easily adjust a surface treatment agent that has wettability that corresponds to the applied energy.

In addition, when silicone is used, it requires a curing time of at least 30 seconds at a high temperature of 100°C or higher, but when silicone is used, it requires a curing time of at least 30 seconds at a high temperature of 100°C or higher. This makes it possible to dry in a short time at a low temperature of 30 seconds or less.

Furthermore, surface treatment agents that use silicone or fluorine compounds form a strong thin film on the surface of the equipment used during manufacturing and coating, making it difficult to clean and making it difficult to clean when using the equipment for other purposes. This causes problems such as splashing. Also,
When the surface treatment agent is insufficiently dried, problems such as adhesion to the back side of the retransfer sheet or transference may occur. However, a surface treatment agent containing fine polyethylene powder not only makes it easier to clean the equipment used, but also does not cause problems such as insufficient drying or back-smearing.

Furthermore, in the case of polyethylene fine powder, material selection for the surface treatment agent is important in order to ensure good dispersion without considering solubility in solvents or compatibility with other resins, waxes, etc. This is very advantageous in terms of manufacturing.

The above-mentioned fine polyethylene powder is blended in a proportion of 0.01 parts by weight to 50 parts by weight, and fine polyethylene powder having an elongation of 100% or more is blended in a proportion of 0.601 parts by weight to 90 parts by weight.

By providing such a surface treatment agent on the sheet, thermal transfer properties, retransfer properties, and scratch resistance can be improved.

It is possible to obtain a retransfer sheet with good image adhesion during handling, sheet fixation during retransfer, and no problems during manufacturing or coating. Furthermore, the wettability can be adjusted as desired.

The ink ribbon used to thermally transfer the desired transfer image onto the retransfer sheet is a wax-based ink that is used in ordinary thermal transfer printers, typewriters, word processors, and other printing devices. However, it is particularly desirable to use an ink ribbon with a two-layer structure consisting of a transferability adjusting layer and an ink layer, which further improves heat-sensitive transferability and pressure-sensitive retransferability. This transferability adjustment layer is provided as a top coat layer on the ink layer, and is a layer that has higher heat-sensitive adhesiveness, hardness, viscosity, and cohesive force than the ink layer, and thus has poor wettability. The heat-sensitive transfer properties onto the retransfer sheet are significantly improved, and pressure-sensitive retransfer can be performed in one piece. Furthermore, by providing the ink layer with pressure-sensitive adhesive properties, the pressure-sensitive retransferability becomes even better.

[Examples] Below, some examples of the present invention will be shown to clarify the present invention more specifically, but the present invention is not limited in any way by such descriptions. That goes without saying.

In addition to the following examples and the above-mentioned specific description, the present invention includes various changes, modifications, and changes 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 improvements and the like may be made.

Example 1 A surface treatment agent having the following composition was coated on a polyethylene terephthalate film having a heat of 50 μm to produce a retransfer sheet with a smooth surface having a contact angle with water of 95″ and a coefficient of static friction of about 0°32. The elongation of this surface treatment agent was 6.
It is 50%.

With this surface treatment agent, a good dispersion could be obtained by dispersing it in a ball mill without considering solubility, compatibility, etc., and it could be produced without any problems during production or coating. After coating, drying was performed at 80° C. for 20 seconds to form a good dry thin film with a heat thickness of 5 μm.

Surface treatment agent composition Weight part ethylene
Vinyl acetate copolymer 9 [EVAFLEX640 manufactured by Koben DuPont Polychemicals Co., Ltd.] - Polyethylene fine powder 1 [Flow Beads LE-10801 manufactured by Seitetsu Kagaku Kogyo Co., Ltd. Toluene 90 On the retransfer sheet 10 obtained in this way Then, the ink was thermally transferred using a thermal transfer type word processor (NP-5100 manufactured by Brother Industries, Ltd.) to obtain a dry transfer material having a desired transferred image.

At that time, it was possible to reduce energy compared to the conventional method and to obtain a good transferred image.

Then, use this obtained dry transfer material to make paper.

When pressure-sensitive retransfer was performed on a material to be transferred such as plastic, a clear retransferred image could be obtained.

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.

By the way, the thickness of this surface treatment agent is 1 μm and 3 μm.
, 5 μm, 5 μm, 3 μm.

Retransferability was good in the order of 1 μm. This is thought to be because the greater the thickness, the greater the absolute amount of elongation.

Furthermore, by determining the amount of polyethylene fine powder added in accordance with the energy applied by the thermal head, good thermal transfer quality and retransfer quality were obtained.

Furthermore, when the equipment used during manufacturing and coating was cleaned using toluene, it was easy to clean and it became possible to use it for other purposes.

[Effects of the Invention] As is clear from the above description, when a dry transfer material is created using a printing device such as a thermal transfer printer, typewriter, word processor, etc., the book is printed on the retransfer sheet. According to the invention, by using a surface treatment agent that has an elongation of 100% or more and contains fine polyethylene powder, it is possible to successfully retransfer a transferred image printed on a surface with better wettability than before. becomes. Therefore, thermal transfer energy can also be reduced and a beautiful printed image can be obtained.

By adjusting the amount of polyethylene fine powder added in accordance with the energy applied during thermal transfer, the wettability of the surface treatment agent can be adjusted, resulting in optimal thermal transfer quality.
Retransfer quality can be obtained.

Furthermore, it becomes possible to use substances that have a contact angle with water of 80° or less, which has not been available until now.

Furthermore, since the ink image has a strong adhesion force, the abrasion resistance is good and handling becomes easy.

Furthermore, since the coefficient of static friction can be increased, it becomes easier to fix the sheet during retransfer, making it possible to form a perfect retransfer image.

Furthermore, since drying can be performed at low temperatures and in a short time, manufacturing costs can be reduced.

Furthermore, the equipment used during manufacturing and coating can be easily cleaned without considering the compatibility with other components of the surface treatment agent or solubility with solvents, and without causing any problems. This makes it possible to obtain a very advantageous surface treatment agent that can be manufactured without any process.

By the way, using a surface treatment agent with a static friction coefficient of 0.25 or more and a contact angle with water of 80 to 120'', ethylene-vinyl acetate copolymer and polyethylene are used as the main components of the above surface treatment agent. By using it, the above effect can be further ensured.

[Brief explanation of the drawing]

The drawing is a sectional view showing an example of a retransfer sheet according to the present invention. In the figure, 10 is a retransfer sheet, 11 is a sheet base material, and 12
13 is a surface treatment agent layer, and 13 is an ink image.

Claims (1)

[Claims] 1. In a retransfer sheet for producing a dry transfer material produced by a thermal transfer method, a surface treatment agent formed on one surface of the sheet has an elongation of 100% or more. death,
A retransfer sheet characterized by containing polyethylene fine powder in its composition. 2. The retransfer sheet according to claim 1, wherein the elongation is achieved by an ethylene-vinyl acetate copolymer contained in the composition of the surface treatment agent. 3. The retransfer sheet according to claim 1, wherein the elongation is achieved by polyethylene contained in the composition of the surface treatment agent. 4. In the retransfer sheet according to claims 1 to 3,
A retransfer sheet in which the surface treatment agent has a static friction coefficient of 0.25 or more and a contact angle with water of 80 to 120°.