JPH0445991A - Sublimation transfer type ink recording medium - Google Patents

Abstract

PURPOSE:To simply produce the above recording medium enhanced in energy efficiency, capable of high speed printing and excellent in halftone reproducibility at low cost by successively laminating a heating resistor layer, a conductive layer, a base layer and a sublimable dye-containing layer. CONSTITUTION:In a recording medium, isolated conductive pattern layers 1 are formed on the surface of the heating resistor layers 2 on a base layer 2 by uniformly providing a large number of mutually isolated minute pattern electrodes having thickness of 500Angstrom -50mum at a pitch of 90mum or less and the heating resistor layer 2 qenerates Joule heat and the sublimable dye in the ink layer is sublimes by the transmission of said heat to complete transfer. A conductive later 3 is composed of an electrode diffusing and refluxing the current flowing in the heating resistor layer and constitutes of a material with volume resistivity of 10-<1>OMEGA.cm. The base layer 3 imparts capacity supporting the current supply sublimation transfer type ink recording medium and has thickness of 1-30mum and the ink later 5 is based on a sublimable dye and a binder and has thickness of 0.5-10mum.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric sublimation transfer type ink recording medium used for converting an electric signal into thermal energy and transferring an ink image to a transfer shrine.

[Conventional technology]

Conventionally, when recording an image corresponding to a predetermined digital image signal on a recording medium, for example, plain paper, a recording method using a thermal transfer recording medium such as an ink donor film is widely known.

Such recording methods include, for example, 1) thermal head transfer method (Japanese Patent Application Laid-open No. 53-84735), 2) electrical transfer method in which the ink layer is energized (Image Electrophotography Society Journal 1982, Vol.), No. 1, p3-9), 3) Current thermal transfer recording method using a print recording medium in which a heat generating layer and a return electrode are provided on an ink support of medium resistance (Japanese Patent Laid-Open No. 58-9
3585 Publication), 4) An energized thermal transfer recording method that uses the heat generated in the heat generating layer by providing a return electrode on the same side as the needle electrode and forming a current path to the return electrode in the heat generating layer of the print recording medium. Proposed.

Among these recording methods, 3) and 4) electrical thermal transfer recording methods have the advantage of relatively fast printing speeds (no need to impart electrical conductivity to the ink, and a high degree of freedom in selecting ink monthly charges). However, since the ink support does not have anisotropic conductivity in these electrical thermal transfer recording methods, the dots spread, the leakage current is large, and the energy efficiency is poor. Alternatively, since the applied current passes through the heat generating layer twice, a lot of energy loss occurs, and since the sliding contact is made twice with the needle electrode and the return electrode, there is also a lot of heat loss due to contact resistance. In order to flow current preferentially to the print recording medium, a resistance of a level equivalent to the conductive layer in the print recording medium is required, which increases heat loss in the conductive layer and has disadvantages such as low dot reproduction accuracy. When various functions are added to the heat generating layer, there is a problem in that the cost increases and the reliability of printing also decreases.

In order to solve this drawback, various thermal transfer recording media have been proposed in which an anisotropic conductive layer consisting of a conductive isolated pattern is provided on the heating resistor layer, and a support layer is an anisotropic conductive layer.

[Problem to be solved by the invention]

By the way, as previously proposed, an anisotropic conductive layer, a heating resistor layer that generates heat due to the manual input of electric signals, a conductive layer, an ink peeling layer, and a heat-melting ink layer are laminated in 1. Although this thermal transfer recording medium improves the problems in the conventional techniques described above, this thermal transfer recording medium is still not satisfactory in terms of halftone reproducibility.

On the other hand, using a thermal head? ? A flower transfer type thermal head transfer method is also known, but it has problems of insufficient energy efficiency and low printing speed.

The present invention has been made in view of the problems as described in (-) in the prior art.

Therefore, it is an object of the present invention to provide energy efficient and
It is an object of the present invention to provide an electro-sublimation transfer type ink recording medium that is capable of high-speed printing, has excellent halftone reproducibility, and can be easily manufactured at low cost.

[Means to solve the problem]

The current-carrying sublimation transfer type ink recording medium of the present invention is characterized by sequentially laminating (7) a heating resistor layer, a conductive layer, a base layer, and an ink layer containing a sublimable dye.

In the current-carrying sublimation transfer type ink recording medium of the present invention (4), an electrically conductive isolated pattern layer may be provided on the heating resistor layer.

FIGS. 1 and 2 are schematic cross-sectional views of an electrically applied sublimation transfer type ink recording medium of the present invention, respectively.

In the figure, 1 is a conductive isolated pattern layer, 2 is a heating resistor layer, 3 is a conductive layer, 4 is a base layer, and 5 is an ink layer.

Next, each layer constituting the electrical sublimation transfer type ink recording medium of the present invention will be described in detail.

In the present invention, the conductive isolated pattern layer does not need to be present on the heating resistor layer, but the conductive isolated pattern layer reduces current flow loss due to current flow resistance during current flow in the thickness direction, and Recording electrode and IFSF? It is desirable to provide a conductive isolated pattern layer because it serves to reduce heat loss due to contact resistance with the surface of the flower transfer ink recording medium, expansion of the heat generating portion, and heat damage.

The conductive isolated pattern layer is formed by providing a large number of micro pattern electrodes isolated from each other like - on the surface of the heating resistor layer on the base layer, and the size of each micro pattern electrode may be the same. May be different. Further, the thickness of the micro pattern electrode is preferably in the range of 500 to 50 mounds, particularly in the range of 2 to 15 mns.

Further, the pitch of the micro pattern electrodes is preferably 90 μm or less, preferably in the range of 15 to 30 μm. pitch or 9
When it is larger than 0 μm, halftone reproducibility decreases7. If it is smaller than 10, the accuracy of pattern creation will decrease and problems will arise in the loss I plane, which is not desirable.

There is no particular restriction on the shape and size of each micropattern electrode as long as each electrode is electrically isolated. However, it is preferable that the size is equal to or smaller than the minimum contact unit of the print recording head that presses against the pattern.Specifically, the diameter or length of one side is 5.
Examples include circular shapes of tunl to 85JJxl, elliptical shapes, rectangular and other polygonal shapes, or arbitrary shapes.

The materials constituting the conductive isolated pattern layer include Cu,
Cr, Sn, Ta, Ti, 71% A 1.1
.

Metals such as Ni, W, Ag, Fe, AI, Pt, RuO2
, SiC, WC, MoSi2, TiC, or other conductive ceramics, polyacetylene, a polymeric material in which a conductive substance is dispersed, or the like, as long as it has conductivity. However, the volume resistivity of the conductive isolated pattern layer needs to be lower than the volume resistivity of the heating resistor layer, and is particularly preferably 1/100 or less. Specifically, the volume resistivity value is 102Ω・cm
Hereinafter, it is preferably in the range of 10-6 to 10-' Ω·cm.

The conductive isolated pattern layer is formed by forming a film using a vacuum evaporation method, a sputtering method, an ion blating method, a screen printing method, a photolithography method, a plasma CVD method,
It can be created using any method such as the riff I-off method.

The heating resistor layer is a layer for generating Joule heat in response to a signal current from the recording head, sublimating the four-color dye in the ink layer by heat transfer, and completing the transfer. The heating resistor layer can be formed by coating a resin liquid in which a conductive substance such as carbon, metal powder, or other conductive powder is dispersed or dissolved on the conductive layer. Examples of the resins used include polyimide resins, polyimide amide resins, aromatic amide resins, polysulfone resins, phosphoricone resins, urea resins, fluororesins, urethane resins, and epoxy resins. The thickness of the heating resistor layer is 0.1
~50 μm, preferably 1.5-5 m.

The conductive layer serves as an electrode for diffusing and refluxing the current flowing into the heating resistor layer, and has a volume resistivity of 10-
Constructed from a material with a resistance of 1Ω・cm or less.

The film thickness is preferably set in a range of 500 to 5 μm. In particular, a range of 0 to 2,000 degrees is preferable in terms of heat leakage and necessary conductive properties. The conductive layer can be formed by various sputter deposition methods or vacuum evaporation methods.

The base layer provides the ability to support the electrodyed sublimation transfer type ink recording medium, and has an important meaning in conveyance in the printing process. The thickness of the base layer is 1 to 30μ
m1 is preferably in the range of 3 to 10 nodes. As the material constituting the base layer, a film-like material made of polyester resin, polyimide resin, polyimide amide resin, aromatic polyamide resin, polysulfone resin, polycarbonate resin, etc. can be used. Since there is no conductivity imparting agent mixed into these films, it becomes easy to make the base aqueous thin, reduce costs, and maintain manufacturing precision.

The ink layer is formed mainly of bamboo leaf dye and binder. The thickness of the ink layer is 0.5 to 10 mm, preferably 1. <
is set in the range of 1 to 3 μm.

Sublimable dyes include dicyanostyryl dyes, quinophthalone dyes, imidazole azo dyes, thiadiazole azo dyes, tricyanostyryl dyes, anthraquinone dyes, naphthoquinone dyes, indoaniline dyes, thiophene azo dyes, etc. can give. In addition, as a binding shrine, polyvinyl alcohol, polycarbonate 1,
, polyester, polysulfone, polystyrene, etc. are used.

[Effect]

Next, the case where printing is performed using the above-mentioned electrically applied sublimation transfer type ink recording medium of the present invention will be explained with reference to FIG.

A current-carrying sublimation transfer type ink recording medium is placed on the side conductive portion of the medium.
Conductive sliding parts such as conductive sliding parts +] and conductive rolls (
(not shown) are conveyed in contact with each other, and in the printing section, an electrical signal corresponding to the image from the pulse drive circuit 9 is applied onto the conductive isolated pattern layer 1 by the print head 6. The applied current flows from the conductive isolated pattern layer to the heat generating resistor layer 2, flows through the heat generating resistor layer in the thickness direction, and reaches the conductive layer 3. At that time, electrical/thermal energy conversion is performed in the heating resistor layer, and the generated thermal energy is thermally propagated through the conductive layer 3 and the base layer 4, reaches the ink layer 5, and the ink layer is connected to the applied electrical signal. Heat accordingly. As a result, the sublimable dye contained in the ink layer sublimates and is transferred as a transfer image 5a onto the transfer plate 7 of the back pressure contact roll 8'', thereby performing printing.

〔Example〕

Next, examples of the present invention will be shown and explained in more detail.

Example 1 A conductive layer was formed by depositing aluminum to a thickness of 2,000 yen on one side of a polyethylene terephthalate film with a thickness of 5 yen by vacuum evaporation. Polyimide wax in which 36% by weight of conductive carbon black was dispersed was applied thereon and dried and cured at 160° C. for 30 minutes to form a heating resistor layer with a thickness of 2 μm. On this heating resistor layer, a conductive isolated pattern layer with a thickness of 5 μm is formed using a polyimide resin in which 72% by weight of Ag particles with an average particle size of 1.0 μm are dispersed by screen printing and lift-off methods. Formed. The micro pattern electrodes of the conductive isolated pattern layer had a diameter of 20 μm and were arranged at a pitch of 30.

Next, an ink layer was formed on one side of the polyethylene terephthalate film to create an electric sublimation transfer type ink recording medium. That is, a magenta dye represented by the following structural formula as a sublimable dye and a polycarbonate resin were sufficiently stirred and dispersed in a 1:1 mixed solvent of toluene and methyl ethyl ketone at a weight ratio of 1:2 to form a coating solution. create(
-It is.

NHCOCH3 This coating liquid was applied to the other side of the polyethylene terephthalate 1 note film by reverse roll coating method, and 12
It was dried at 0°C for 10 minutes to form an ink layer with a thickness of 2 μm.

Next, a rectangular shape of 80 m x 70 μm with a width of 21.0 mm having contact bumps of height 18 μm with a pitch of 100 μm.
line print head at a linear speed of 1.00 mm/s,
The above-mentioned energized R color transfer type ink recording medium was brought into contact with the recording medium and then fed. At that time, press Transfer +1 with an elastic platen roll so that the bump-shaped contact energization recording part of the line print head comes into contact with the energization H flower transfer type ink recording medium with a linear pressure of 600 g/cm to send the electric signal. was applied to perform image printing. The applied voltage is OV, the basic clock is 25 μs, and the number of gray levels per dot is 40.
0, halftone reproduction was performed according to human power. Input signal pulse width and optical density (magenta color density) at that time
Figure 4 shows the relationship between As is clear from Figure 4,
The electro-sublimation transfer type ink recording medium exhibited good no-ft tone reproducibility.

Example 2 An aluminum layer with a thickness of 2,500 layers was formed on a polyimide film with a thickness of 12 μm by vacuum evaporation. Next, on the conductive layer formed of the aluminum layer,
A coating solution made of aromatic polyamide in which 41% by weight of conductive carbon black was dispersed was applied and dried (step 7) to form a heating resistor layer with a thickness of 4 mils.Furthermore, chromium was deposited using a vacuum evaporation method. A chromium film with a thickness of 3,000 wafers was formed.A conductive isolated pattern layer was formed from this chromium film by photolithography with a pitch of 20 squares and a square pattern electrode having a -side of 15 IJn square.

Next, an ink layer is formed on the other side of the polyimide film,
I also created an electrically conductive four-color transfer type ink recording medium. That is, cyan purple shown by the following structural formula as a four-color dye and polyvinyl alcohol were added to ethyl alcohol at a weight ratio of 2:1, dissolved by heating in BD'C, dispersed, and applied. I made a liquid.

Apply this coating liquid to the other side of the polyimide film, 1.
1. It was dried in OoC to form an ink layer with a thickness of 1.5 μm, and an electric sublimation transfer type ink recording medium was prepared (7).

Next, with an applied voltage of 2V, the pulse width was 500μS to 1ms.
The halftone reproducibility by pulse width modulation was evaluated by dividing the range into 256 steps.

As a print head, pitch 1.25 Bm, 100μ
The printhead used had a contact current recording part in the form of a square bump measuring m x 100m, and had a printing width of 150cm.

Synthetic paper coated with polyester resin was sandwiched between an electrically applied sublimation transfer type ink recording medium and an elastic pressure roll, and printing was performed by pressing the print head against the paper at a pressure of 800 g/cm. As a result, good halftone reproducibility was obtained.

Example 3 An electrical sublimation transfer type ink recording medium was produced in the same manner as in Example 2, except that a magenta dye represented by the following structural formula was used instead of the sublimable dye in Example 2.

〔Effect of the invention〕

Since the electro-sublimation transfer type ink recording medium of the present invention has the above-described structure, it can be easily manufactured at low cost. In addition, it has high energy efficiency, enables high-speed printing, and has excellent halftone reproducibility.

[Brief explanation of drawings]

FIGS. 1 and 2 are schematic 1tli side views of the current applied sublimation transfer type ink recording medium of the present invention, and FIG. 3 illustrates the state of printing using the current applied sublimation transfer type ink recording medium of the present invention. FIG. 4 is a graph showing the relationship between optical density and input signal pulse width in Example. DESCRIPTION OF SYMBOLS 1... Conductive isolated pattern layer, 2... Heat generating resistor layer, 3... Conductive layer, 4... Base layer, 5... Ink layer, 6... Print head, 7... Transfer material , 8. Back pressure contact roll, 9... Pulse drive circuit. Applicant Fuji Xerox Co., Ltd.

Claims (2)

[Claims] (1) An electrical sublimation transfer type ink recording medium comprising a heating resistor layer, a conductive layer, a base layer, and an ink layer containing a sublimable dye, which are successively laminated. (2) The electrically conductive sublimation transfer type ink recording medium according to claim 1, wherein an electrically conductive isolated pattern layer is provided on the heating resistor layer.