JPH0363184A - Image receiving material for sublimation type thermal transfer recording - Google Patents

Abstract

PURPOSE:To obtain an image receiving material excellent in releasability and not lowered in gloss even in a high density image part by adding a reaction product of a vinyl chloride compound containing active hydrogen and an isocyanate compound in a dye receiving layer and forming the part in contact with the dye receiving layer of a base material from a PET film. CONSTITUTION:A dye receiving layer contains a reaction product of a vinyl chloride compound containing active hydrogen and an isocyanate compound and at least the part in contact with the dye receiving layer of a base material is formed from a PET film. As the vinyl chloride compound containing active hydrogen, a vinyl chloride/vinyl acetate copolymer is designated. As the isocyanate compound, tolylene diisocyanate is used. At least the part in contact with the dye receiving layer of the base material is formed from the PET film. By this method, the surface of an image is smooth as it is even when recording is performed by the application of high energy and gloss is not lowered even in a high density image part.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image receptor for sublimation type thermal transfer recording, which is used in combination with a thermal transfer recording medium having a transfer layer containing a sublimable dye.

[Conventional technology]

In recent years, the demand for full-color printers has increased year by year, and the recording methods for these full-color printers include electrophotography,
Inkjet methods, thermal transfer methods, etc. are known, but
Above all, it is easy to maintain.

The thermal transfer method is often used because it is noiseless.

This thermal transfer method is based on the ink layer surface of a thermal transfer recording medium (color ink sheet) in which an ink layer in which a colorant is dispersed in a heat-fusible substance or a sublimable dye is dispersed in a resin binder is provided on a substrate. An image receptor (image-receiving sheet) is placed on the image-receiving sheet, and thermal energy controlled by an electric signal from a laser or a thermal head is applied from the recording medium side to thermally melt transfer or sublimation transfer the ink in that area onto the image-receiving sheet. This is a recording method that forms an image using

This thermal transfer recording method is as described above.

Depending on the type of recording medium used, it is broadly divided into thermal melt transfer type and sublimation transfer type, but in the latter case in particular, the dye sublimates in monomolecular form in response to thermal energy from a thermal head etc. Therefore, it has the advantage that halftone images can be easily obtained and the gradation of the image can be controlled at will, so it is considered to be the most suitable method for full-color printers.

However, this sublimation type thermal transfer recording method uses a color ink sheet as a recording supply and performs heating recording selectively based on image signals. One ink sheet to which "black" has been added is used, and then any unused portions are discarded, so the running cost is high.

However, in order to improve these drawbacks, (1,) the speed of the image receiving sheet is set to 0 times the speed of the ink sheet (n>1).
Repeated printing with one sheet running
Double mode recording method, (2) - Field-sequential ink ribbon (ink sheet) in which each color ink of yellow, magenta, and cyan ("black" can be added if necessary) is applied in strips to a predetermined area of a roll of ink ribbon. In recent years, a recording method using a line head or a serial head has been used. The 0x mode recording method in (1) above is a method in which printing is performed multiple times using a relative speed method that gradually shifts the overlap between the previously used portion of the ink layer and the later used portion (speed difference recording method). It is, again.

Of the above recording methods (2), the field sequential method using a line head is suitable for high-speed printing, while the line sequential method using a serial head switches the color signal every 1 recording line,
After line gold printing, the line is fed to the sub-scanning method to perform color printing.

[Problem to be solved by the invention]

No matter which method above is adopted.

In the conventional sublimation thermal transfer recording method, a dye-receiving layer made of thermoplastic polyester resin, etc., which exhibits strong dyeability against sublimation dyes, is formed on a substrate (paper, synthetic paper, plastic film, etc.) as an image-receiving sheet. The reality is that things have been used. However, with conventional image-receiving sheets, if the dye-receiving layer is not cured, fusion tends to occur and peelability is not sufficient, and especially in the 0x mode recording method, a strong frictional force is applied between the ink sheet and the image-receiving sheet. For.

During recording, it was occasionally observed that fusion occurred or the sheets were damaged.

The present invention eliminates these defects and has excellent releasability that can be used even in the 0x mode method, which requires even higher releasability than the normal dye sublimation thermal transfer recording method (including the method (2) above). In addition, it is an object of the present invention to provide an image receptor for sublimation type thermal transfer recording in which gloss does not decrease even in high-density image areas.

[Means to solve the problem]

The present invention provides an image receptor for sublimation type thermal transfer recording in which a dye-receiving layer capable of being dyed with a sublimable dye is formed on a substrate, and the dye-receiving layer contains a reaction product of a vinyl chloride compound containing active hydrogen and an isocyanate compound. Vk, the substrate is characterized in that at least the portion in contact with the dye-receiving layer is a PET film.

That is, the sublimation type thermal transfer recording image-receiving sheet of the present invention has (a)
Since a dye-receiving layer whose main component is a reaction product of a vinyl chloride compound containing active hydrogen and an incyanate compound is formed on the substrate, the dye-receiving layer has excellent dyeability, peelability, light resistance, and It provides excellent storage properties, and further improves releasability due to the curing reaction between active hydrogen and the isocyanate compound, and (b) due to the hardness of the dye-receiving layer and the hardness of the PET film. Even when recording is performed with high energy application, the image surface remains smooth, and the gloss level does not decrease even in high-density image areas.

Examples of vinyl chloride compounds containing active hydrogen used in the dye-receiving layer of the present invention include vinyl chloride/vinyl acetate copolymers modified with polyvinyl alcohol, and commercially available products include, for example, Union Carbide Co., Ltd. VAGH, VROH, etc. manufactured by Denki Kagaku Kogyo Co., Ltd. and Denkabinir 1OOOGK7.1000GK, 100OG manufactured by Denki Kagaku Kogyo Co., Ltd.
Examples include KS. Further, as the isocyanate compound, various incyanate compounds such as tolylene diisocyanate, hexamethylene diisocyanate, 4,4-diphenylmethane diisocyanate, and triphenylmethane triisocyanate are used, and adducts of these with hexanetriol and the like may be used. You can also do it. In addition, the usage ratio of the vinyl chloride compound containing active hydrogen and the isocyanate compound is 0.2 to 0.2 to the molar ratio of NC010H.
A range of 2.0 is preferred.

The dye-receiving layer of the present invention may contain conventionally known dyeable resins such as polyester resins, polycarbonate resins, styrene resins, vinyl chloride resins, silicone resins, and the like.

Further, in the present invention, a release agent such as amino-modified silicone, epoxy-modified silicone, alkyd-modified silicone, etc. can be contained in the dye-receiving layer. Use of these silicones further improves the effect of preventing heat fusion with the sublimation type thermal transfer recording medium. The amount added is preferably 10 weight or less based on the amount of resin in the dye-receiving layer.

Fillers can also be included in the dye-receiving layer.

Examples of fillers include white pigments such as silica, titanium oxide, and calcium carbonate, and the amount added is preferably 5 to 60% by weight based on the amount of resin in the dye-receiving layer. may also contain surfactants, ultraviolet absorbers, antioxidants, etc. as appropriate.

Furthermore, the substrate in the present invention is a PET film at least in the area in contact with the dye-receiving layer.

Therefore, it is sufficient to satisfy this condition.

The base materials include ■PETPE itself, ■high-quality paper, processed paper, synthetic paper, etc. (including those laminated together as appropriate)
Examples include those with a PET film laminated thereon, and (2) those with PET films laminated on both the front and back sides of high-quality paper, processed paper, synthetic paper, etc.

PET films are generally transparent and therefore the use of white PET films containing white particles is particularly preferred. Further, in order to prevent curling, it is also preferable to use a support in which both sides of a sheet of paper are laminated with a PELT film, or a support in which a PET film/high quality paper is laminated with a layer of 7 layers.

The thickness of the substrate is preferably 50 to 200 μm, and the PET film in contact with the dye-receiving layer preferably has a thickness of at least 10 μm. The coating amount of the dye-receiving layer is 0.1 to 200 μm in terms of solid content. 20 g/n (is suitable.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples. Parts here are by weight.

Example 1 A mixture having the following composition was thoroughly mixed and dispersed to prepare a dye-receiving layer coating liquid [liquid A].

[Liquid A]

Isocyanate (trade name Coronate L; 5 parts manufactured by Nippon Polyurethane Industries, Ltd.) An image receptor (image receptor sheet) for sublimation type thermal transfer recording was prepared.

On the other hand, as a back layer, a silicone cured resin film (approximately 1 mm thick) is used.
．． cm) on a PET film with a thickness of about 6 μm,
A coating liquid for an ink layer (dye transfer layer) [liquid B] having the following formulation was applied to a thickness of about 2 prm to obtain a sublimation type thermal transfer recording medium (ink sheet).

[Liquid B]

40 parts of toluene 40 parts of methyl ethyl ketone
ET film (product name Melinex 329: ICI R)
) and dried for 1 minute at a drying temperature of 75°C to form a dye-receiving layer with a thickness of about 5 μs, and then further coated at 80°C for 3 minutes.
Methyl ethyl ketone according to the present invention 45 parts toluene
45 copies of the obtained sublimation type thermal transfer recording medium and image receiving sheet are stacked so that the ink layer of the sublimation type thermal transfer recording medium and the dye receiving layer of the image receiving sheet face each other, and a thermal head is applied from the back side of the sublimation type thermal transfer recording medium. Images were recorded by changing the heating energy.

Here, the ratio (np/nx) between the running speed (nl) of the sublimation type thermal transfer recording medium and the running speed (np) of the image receiving sheet is n
Recording was performed under J0 conditions. The recording density of the thermal head is 6 dots/ll11, and the recording output is 0.
．． It was 42V/dot.

Example 2 White PET (approximately 60 iLm thick)/Yaw 1 as the base
An image-receiving sheet was prepared in exactly the same manner as in Example 1, except that a three-layer adhesive sheet of paper (approximately 50 μm thick) and 7 synthetic paper (approximately 60 μm thick) was used.

Subsequently, image recording was performed in the same manner as in Example 1.

Comparative Example 1 Except for using the following [Liquid C] as the coating liquid for the dye-receiving layer,
A comparison image-receiving sheet was prepared in the same manner as in Example 1, and an image was recorded.

[Liquid C]

Toluene 40 parts Methyl ethyl ketone 40 parts Comparative Example 2 A comparative image-receiving sheet was prepared in the same manner as in Comparative Example 1, except that the following [Liquid D] was used instead of [Liquid C] in Comparative Example 1, and image recording was performed. I did it.

[Liquid D]

Toluene 40 parts Methyl ethyl ketone 40 parts Comparative Example 3 A comparative image-receiving sheet was prepared in the same manner as in Example 1, except that synthetic paper YUPO #175 was used as the substrate, and an image was recorded.

After the above images were recorded, the surfaces of the sublimation type thermal transfer recording medium and the image receiving sheet were visually observed. The results are shown in Table 11.

Table 1 On the other hand, gloss alone is not necessarily sufficient; both the hardness of the dye-receiving layer and the hardness of the substrate are required. It is believed that an image receptor with no decrease in optical density can be obtained.

Claims (1)

[Claims] (1) A dye-receiving layer capable of being dyed with a sublimable dye is formed on a substrate, and the dye-receiving layer contains a reaction product of a vinyl chloride compound containing active hydrogen and an isocyanate compound. 1. An image receptor for sublimation thermal transfer recording, wherein the substrate is at least a PET film in contact with the dye-receiving layer.