JPS5842490A - Recording material for electrifying transfer - Google Patents

Abstract

PURPOSE:To prevent the breaking of dot shape for raising the definition of recording by making up a recording material for electrifying transfer from a composite layer consisting of a base layer composed of specific carbon black and a specific binder and an ink layer. CONSTITUTION:A recording paper 2 is lapped on a recording material 1 for electrifying transfer, a recording electrode needle 3 and a return electrode 4 are contacted with the recording material 1, a signal voltage 5 is applied to the recording material 1, and ink 7 is transferred to the recording paper 2 for recording. Such a recording material 1 is made up of a composite layer consisting of a base layer 11 containing carbon black with a surface area of 200m<2>/g or more and a binder with a melting (or softening) point of 150 deg.C or higher as main component and having a volume intrinsic resistivity of 10<-1>-10<-2>ohm-cm and a thickness of 5-30mum and an ink layer 12 containing carbon black with a surface area of 200m<2>/g or more and a binder with a melting (of softening) point of 50-200 deg.C and having a volume intrinsic resistivity of 10<-2>-10<1>ohm-cm and a thickness of 1-30mum. In this case, the resistivity value of the ink layer 12 is lower than that of the base layer 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording material for electrical transfer, and more specifically, it is useful for printing records such as noiseless typewriter-1 electronic computer printing, output of electronic meter The present invention relates to a recording material for electrical transfer.

As electronic computers, factor t IJ, etc. have become increasingly sophisticated, printers, which are their terminal devices, have also come to occupy an important position. These terminal devices can be broadly divided into invacuum printers, direct mail printers, and non-invacuo printers.
Furthermore, the latter recording methods include (1) electrophotography, (2) thermosensitive recording, and (3) release! Recording, (4) Thermal transfer, (5)
Electric transfer is well known. However, the former impact printer has a defect in that it cannot avoid the noise generated due to its mechanism.

On the other hand, the recording method used in the latter (non-impact printer) is also advantageous in that it does not generate noise, but has various problems.

In other words, the electrophotographic method requires five steps: priming, dew, image transfer, and cleaning, making the process complex. There are drawbacks.

In the x thermal recording method, there are still problems with the storage stability of the thermal recording paper used therein, and the thermal recording paper itself has the disadvantage that it is processed paper and plain paper cannot be used. Although the discharge recording method is advantageous in that it is capable of instantaneous L transfer to plain paper, it has five drawbacks such as the generation of odor and burnt residue caused by discharge destruction. In addition, since the thermal transfer method uses a thermal head, it is difficult to obtain high-density images.
1111), and the recording speed is even slower (
im(6)/dot angle is the limit).

Although it is the same non-impact printer method, it is different from the above method.The electric transfer method (current transfer recording method) can obtain high-density images on plain paper, the recording speed is fast, and the equipment used in this method is It has the advantage of being able to be easily controlled. For this reason, several proposals have been made regarding the current transfer paper (recording material for current transfer) used in this system and further improvements to the system.

Examples include (1) USP 2713822 and USP 3744611 for a type (electrothermal transfer method) in which the base layer generates heat and conducts heat to the ink layer;
In the past, a paper having a three-layer structure of an insulating layer (or resistance layer), a conductive layer, and an ink layer has been used as an electrically conductive transfer paper, but this layer structure is complicated. Furthermore, as a product of this type, energized transfer paper with a 2-NO structure is used in Japanese Patent Application Laid-Open No. 54-58511, but manufacturing of this energized transfer paper involves considerable difficulty. be.

JP-A-49-38629 and JP-A-53-7 are of the type in which electricity is applied to the tapped ink itself (current transfer method).
Publications such as No. 246 and Japanese Unexamined Patent Publication No. 56-8276 describe two-layer electrical transfer paper in which a conductive ink layer is provided on an anisotropically conductive paste. Sex pace is a special material J? The cost is high because it is manufactured using a sophisticated manufacturing method, and on top of that, the current transfer paper of tL et al. still has some problems.

For example, (a) the method described in JP-A No. 49-38629 adopts a method of blending ferromagnetic metals under a perpendicular magnetic field, so that a homogeneous anisotropic conductive paste over a large area is produced. Things that are difficult to create.

(b) In the method described in JP-A-53-7246, an anisotropic conductive paste is created by dispersing metal powder in a binder, but it is difficult to uniformly disperse the metal at this time. An isthmus occurs in a part of the dot, creating a short circuit, making it impossible to conduct electricity faithfully to the stylus, resulting in the dot shape being distorted.Solution #1! decrease in power. Furthermore, in the method described in e→JP-A-56-8276, a conductive material such as metal or carzene is added to silicone rubber.
．． The idea is to use a vertical conductive base with columnar VC buried in the direction, but this method currently has some drawbacks, such as the resolution being limited to 4 lines/11111 at a pitch of 5-250 μm.

In any case, in the case of (1) above, heat is transferred indirectly to the ink (ink), which results in poor thermal efficiency and defects such as poor dot quality due to heat diffusion.
Furthermore, the above (11) has drawbacks in terms of performance because it has an anisotropically conductive pace as a component, and also has the drawback of high cost because it uses a special #family and #manufacturing method. ing.

The inventors of the present invention have considered the merits of the current transfer recording method (the ability to perform high-temperature recording up to about 16 lines/l1IJI, Q, 5m580/dot).
(The recording speed is fast, the device is compact because development and transfer can be done only with the stylus, and the ability to record on plain paper, etc.). In order to overcome the drawbacks of current transfer paper (current transfer paper), we have already proposed an hC recording material for current transfer, which consists of only one layer of a dedicated transfer layer. However, when trying to achieve high sensitivity with this single-layer 6-electroelectric transfer recording material #+ (4-electroconductive ink sheet), the strength of the ink sheet decreases, which limits the ability to increase sensitivity. I can't deny it.

Furthermore, by combining the polished rice that the present inventors have researched and examined, a base layer with appropriate physical properties, and an ink layer, a special base layer (anisotropically conductive・We have found that even if you do not have the following pace (fJ), the sufficiency of a high-concentration record with high analytical ability can be reduced.

The present invention was completed based on such knowledge/1. It is something that

Therefore, the object of the present invention is to solve the disadvantages of using a special base layer as in the above-mentioned prior art - distortion of dot shape due to variations in quality, decrease in resolution, and high cost due to special manufacturing method using special materials. It is an object of the present invention to provide an electrical transfer recording material which eliminates the above problems. Another object of the present invention is to provide an electrical transfer recording material that has gradation properties and high sensitivity comparable to those of the single-layer ink sheet described above, and also has good strength.

That is, in the present invention, a recording body and a recording material for electrical transfer are placed one on top of the other, a return electrode is brought into contact with the recording material, and a recording electrode needle is brought into contact with the surface of the recording material to apply a voltage to the recording material. The recording material used in the current transfer recording method for transferring ink onto the recording medium is mainly composed of carbon black with a surface area of 200 g or more and a binder component with a melting point or softening point of 150° C. or more, and has a volume resistivity. 10”~10”0m thickness 5~30μm
base layer, carbon black with a surface area of 20og7.1 or more, and a binder component with a melting point or softening point of 50 to 200°C as the main components, and a volume resistivity of 10-1 to 101.
It consists of a multilayer ink layer with a thickness of 1 to 30 μm at 0 m,
However, the resistance value of the ink layer is lower than that of the base layer.

Hereinafter, the present invention will be explained in more detail based on the accompanying drawings. Figure 1 shows a conventional anisotropically conductive base layer 11'.
FIG. 2 is a diagram showing an outline of recording using a recording material 1' for electrical transfer, which is composed of a conductive ink 412' and a conductive ink 412'. 3 is a diagram showing an outline of recording using a comparative electrical transfer recording material 1" consisting of the following. FIG.・Figure 4 is a diagram showing the outline of the ink sheet, Figure 5 is a diagram for investigating the shape anisotropy of a two-layer ink sheet, and Figure 5 is a diagram showing the shape anisotropy of a two-layer ink sheet. Figure 6 is a graph showing the relationship between the surface area of the carbon black contained in the conductive ink sheet and the electrical conductivity of the conductive ink sheet. FIG. 8 i1. is a partially cutaway perspective view showing a state in which actual current transfer recording is performed using a multi-stylus. A multi-stylus with electrode needles arranged in a staggered manner, FIG. 9 shows a multi-stylus with integrated return electrodes.

In addition, in these figures 1 IITVc & f are attached,
9- 2 is a recording medium (plain paper, resin sheet, or three-dimensional object may be used), 3 is a recording needle (recording electrode needle), and 3' is done! 4 and 4' are return electrodes, 5 is a recording applied voltage, 6 (represented by an arrow) is a recording current, and 7. is a multi-stylus.
7' or fμ Recording material 1. Dot shape seen from above of heat transfer ink transferred from 1' or 1' to recording medium 2, 8
is a leather roller. Further, the ink sheet 1 is composed of a multilayer structure including a base layer 11 (the layer on the polar side) and an ink layer 12 (the layer on the recording body side).

In order to perform electrical transfer recording, as shown in Figure 3,
The ink layer 12 of the recording material 1 and the recording body 2 are densely layered, and a zigzag signal voltage 5 is applied from the recording needle 3 to the base layer 11 of the recording material to conduct the inside of the recording material 1 to form a return electrode 4. energize.

At this time, as will be explained later with reference to FIG.
The current density (J) directly below is maximum, and since the return electrode 4 has a wider contact area than the recording needle 3 (or multi-stylus 3'), the current spreads toward the return electrode 4.
, the flow density becomes smaller.

10- Due to the Joule heat generated by this energization, the ink in the ink layer 12 (carbon black particles and the binder component present around them) is softened or melted, and the recording body 2IC
metastasize.

As described above, the paste layer 11 of the ink sheet IIc is made of carbon black with an rC1 surface area of 2 oom/V or higher dispersed in VC in a binder component ((IW resin)) with a softening point or melting point of 150° C. or higher. .The value of "softening point or melting point" here refers to the value of the resin powder at 5 ton/c.
Form a pellet with a load of III, apply this fl (Kikushimazu Flow Tester IC7>
This is the temperature at which flow starts under the conditions of a load of 100 Q/m% and a temperature increase of 6° C./min.

Suitable binder component materials for the paste layer 11 include styrene resins such as polystyrene, polyvinyltoluene, styrene-butadiene copolymer, and vinyltoluene-acrylic copolymer, and acrylic resins such as polymethyl methacrylate and polyethyl acrylate. based resins, poly]t vinyl, vinyl chloride-vinyl acetate copolymers, celluloses such as ethyl cellulose, cellulose acetate, and cellulose triacetate, polyacrylonitrile, nylon, polyacetate resin, polyvinyl butyral resin, polycarbonate resin, polyethylene terephthalate, poly Vinylidene chloride, phenolic resin, polyethylene, polypropylene, and any other substance that has film formation and a softening point or melting point of 150° C. or higher can be used. Among them ~ triacetate cellulose,
Polycarbonate resins, high softening point polyvinyl butyral resins, and the like are suitable.

On the other hand, as described above, the ink layer 12 of the ink sheet 1 is composed of carbon black having a surface area of 200 m/9 or more dispersed in a binder component having a softening point or melting point of 50 to 200°C. be.

Examples of one-component materials suitable for such an ink layer 12 include waxes such as paraffin wax, polyethylene wax, and carnauba wax, 2-ethylhexyl acrylate, lauryl methacrylate-1', and n-butyl methacrylate. Acrylic resin with low Europeanization point, low molecular weight polystyrene, styrene-citadiene copolymer,
In addition to styrene-acrylic-A' polymers, petroleum resins, oils and fats such as linseed oil, glycols such as polyethylene glycol and polypropylene glycol, low molecular weight boria, ethyl-vinyl acetate copolymers, etc. can be exemplified.

Among them, carnauba wax, low molecular weight polystyrene,
It is preferable to use a low molecular weight styrene-(n)butyl methacrylate-1 copolymer.

Note that each of the binder components constituting the paste layer 11 and the ink layer 12 may be used alone or in combination of two or more.

In addition, since the ink Jfjj12 has the role of energizing the paste layer 11 faithfully to the shape (diameter and original shape) of the pole needle, and at the same time melting with low energy and transferring to the recording medium 2, As mentioned above, the binder component used in the 4-th layer 11 is
It must have a melting point or softening point of 50 to 150°C, taking into consideration the melting point or softening point (150°C or higher) of the binder component. If it is lower than 50 degrees Celsius, it will cause stains during transportation or during pressure bonding, whereas if it is higher than 150 degrees Celsius, it will melt with low energy and form a good thermal transfer ink 7 together with carbon black (coloring component). I won't.

For both the paste layer 11 and the ink layer 12, various plasticizers may be used in combination as flexibility imparting substances, if necessary. Such plasticizers include phthalate esters (dizotyl phthalate, dioctyl phthalate, etc.) and phosphate esters (
triethyl phosphate, tricresyl phosphate, triphenyl phosphate, etc.), fatty acid esters (dibutyl sepacate, etc.)
, glycol-based (polyethylene glycol, polypropylene glycol, triethylene glycol, etc.), glycol ester-based (diethylene glycol dipenzoate, etc.), wax-based (animal and vegetable waxes, mineral waxes, etc.), fatty acid metal salts (stearin, (zinc acid, magnesium oleate, etc.). The amount of these flexibility-imparting substances added is 1 resin (binder component).
A suitable range is 5 to 200 parts by weight per 00 parts by weight. Among these, the one in which a small amount of polyethylene glycol (flexibility imparting substance) is added to the paste layer 11 gives good results.

In order to obtain color copies, the ink layer 12 may contain known organic or inorganic dyes/pigments such as phthalocyanine, alkali blue, spirit black, benzidine yellow, fast red, crystal violet, etc.
Coloring components such as iron oxide and cadmium sulfide may be added.

The volume resistivity value of these layers is 10-1 for the paste layer 11.
In the range of ~103 Ωm, the ink layer 12 is 1O-1 to 10
(The volume resistivity of the base layer 11 is 1
If it is lower than 0-1Ωσ, the current will flow laterally from the pace layer directly under the electrode needle, and conversely, if it is higher than 10Ωσ, it will be difficult for the current to flow, and if you try to record, you will have to use a fairly high voltage. will have to be applied. If the volume resistivity of the ink layer 12 is lower than 104 Ωm, the current value for recording one dot will be 100 mA or more even when IOV is applied, making it unsuitable for simultaneous application distribution using multiple styluses, and it will be higher than 101 Ωm. In order to obtain the current density necessary for recording, it becomes necessary to apply a high voltage of 300 V or more, which is not preferable.

Here, what should be noted about the relationship between the resistance values of the paste layer 11 and the ink layer 12 is that the volume resistivity value of the paste layer 11 must always be greater than the volume resistivity value of the ink layer 12. That's true. If this relationship is not established, current transfer recording will not be performed, but even if it is performed, a good quality dot image will not be obtained.

As a resistance control for the paste layer 11 and as a resistance control for the ink layer 12 and optionally as a coloring agent,
The surface area is 2oom/,! A car I car black of i' or more is used.

As shown in FIG. 5, when car black having a surface area of less than 200 m/9 is used, even a content of 25% by weight provides a resistance value of 100% or more. In particular, the paste layer 11 must be made rich in binder components with as little amount of car black as possible, since a high content of car black will reduce the film forming ability and easily cause stylus stains. Therefore, a highly conductive car black is required. The content is usually 5 to 25% by weight, preferably 5 to 10% by weight.
The content is in weight%.

Furthermore, when the amount of carne black in the ink layer 12 increases, the viscosity increases when melted or softened, making it difficult for the ink to transfer to the recording medium 2. Therefore, the content is usually 5 to 3.
0% by weight, preferably 10-20% by weight.

Figure 6 shows the surface area of 15 types of commercially available car-in blacks and the electrical conductivity (volume specific 17 - reciprocal of resistance) of the ink sheet.
It can be seen that a surface area of 11 or more is required.

However, some channel-type casen blacks with a pH of 5 or less have high resistance even if their surface area is more than zoom/fi, and conversely, the surface area is as small as 133 rrl/fl, but the oil absorption is 560CQ7100g (usually 50~300c). !
-7100g) and a large particle size of about 28μm (usually 10 to 20μm).
rax -L) has a relatively low resistance and can be used.

In order to actually produce the recording material of the present invention, a binder component and a conductive material (Rikizenblack) as described above are dissolved or dispersed in a suitable solvent and then a glass plate, a metal plate, etc. A paste layer 11 with a thickness of 5 to 30 μm (volume resistivity of 10 −1 to 10 8 Ω crn) is formed by coating and drying, and on top of this, a binder component and a coloring component (car black which also serves as a conductive material) are applied. After dissolving or dispersing the ink in a suitable solvent and drying it to form an ink layer 12 with a thickness of 1 to 30 μm (volume resistivity 18-124 to 101 Ω crn), this is applied to a glass plate, metal plate, etc. Just peel it off. Examples of the solvent include tetrahydrofuran, 1,2-dichloroethane, methyl ethyl ketone, toluene, petroleum ether, ethyl acetate, dimethylformamide, and methanol.

In order to carry out current transfer recording using the recording material manufactured in this way, as shown in FIG. 3 or FIG. A current signal from the recording applied voltage 5 may be applied to the pace/1iix1 through the recording needle 3 or the multi-stylus 3'.

The energization conditions, number of scanning lines, etc. greatly affect image formation, but generally 10 to 200 V and energization time of 0.2 to 1
tn Sea, the number of scanning lines is about 3 to 20/8. The recording material 1 and the recording body 2 are brought into complete contact with each other. The recording material of the present invention can be used repeatedly because all the coloring components (curtain black in the ink layer 12, etc.) do not transfer onto the recording medium 2 even when a relatively strong current is applied. .

As described above, by using the recording material of the present invention, a high quality image can be quickly formed on a recording medium such as plain paper with low recording energy. Although detailed studies have not been conducted on whether high-density images can be obtained at high recording speeds by using this recording material, it is widely accepted that by functionally separating the roles of the base layer 11 and the ink layer 12, This is thought to be due to the fact that the material for the recording material could be selected, which made it possible to reduce the overall thickness of the recording material.

Furthermore, the base layer 11 in the recording material of the present invention has a completely different structure from the conventional special and expensive anisotropic conductive base layer, and is simply made of the conductive material used for the ink layer 12 (the surface area is Since a uniformly dispersed layer containing 200 tr? Since the dot layer is more uniform than the base layer, it has the effect of allowing high-quality dot recording that is faithful to the shape of the recording stylus.

The shape anisotropy of the ink sheet 1 of the present invention will be explained with reference to FIG. It becomes possible to concentrate on the most faithful parts.

For example, R (]) = 10 , approximately 90% of the current flows in a vertical direction and in a manner that faithfully reflects the stylus shape. This means that if the resistance of the ink layer 12 is sufficiently small, the stylus surface a is one electrode surface, and the ink layer 12 is directly below the stylus (or the cylindrical part with a diameter that is at most the stylus diameter plus the thickness of the base layer 12). This means that b can be regarded as the other virtual electrode surface.

Example 21 - Polycarbonate resin 5 parts by weight Carzen black (surface area 1oooom/, 9)
95 parts by weight 1,2-dichloroethane 9
8 parts by weight of a mixture consisting of 8 parts by weight in a glass ball mill.
The time-dispersed mixture was applied onto a glass substrate using a blade with a gap of 150 μm and dried to form a base layer having a resistance of 2Ωα and a thickness of about 15 μm. Furthermore, on this paste layer, a mixture of the following formulation was dispersed in a glass ball mill for 8 hours, and the mixture was applied with a blade having a gap of 200 μm and dried to form an ink layer.

Polystyrene (molecular weight approximately 400) 10 parts by weight Cardan black (surface area 1000 m/, li')
eo parts by weight cyclohexane 50
0 parts by weight The laminated base layer and ink layer were integrated and peeled off from the glass substrate to prepare a recording material for electrical transfer. The total thickness of this recording material was about 20 μm, and the resistance was 0.4 Ωm.

Next, as shown in FIG. 7, a recording medium (plain paper) 2 is brought into close contact with the ink layer 12 of this recording n- material.
Under that condition, the multi-stylus 3' (pole needle diameter is approximately 6
0μm, recording needle density 16/mm) and 10
100V-0 between the return electrode 4 which is 111111 away,
When a pulse voltage of 2m5fXJ was applied, 20mA
A recording current of 100 μm was observed, and a clear transferred image of original dots with a dot diameter of about 80 μm and a dot degree of 1.0 was obtained on the plain paper.

For comparison, a recording material for electrical transfer was prepared in exactly the same manner except that the carbon black used in the base layer and ink layer was replaced with one having a surface area of about 180 Ti. The resistance of the base layer was 2000 Ωα, and the resistance of the entire recording material was 500 Ωm. Next, when recording was performed in the same manner as before using this recording material, even under the application condition of 500V-1m8ec, 1f
Only a recording current of less than flA was observed, that is, no dot recording was performed because no current was substantially applied.

[Brief explanation of the drawing]

Figure 1 is a diagram showing an overview of recording using a conventional recording material for current transfer, Figure 2 is a diagram showing an overview of recording using a comparative recording material for current transfer, and Figure 3 is a diagram showing an overview of recording using a comparative recording material for current transfer. A diagram showing an overview of recording using the recording material for electrical transfer according to the present invention, FIG. 4 is a reference diagram for investigating the shape anisotropy of a conductive ink sheet, and FIG. 5 is a diagram showing the surface area of carbon black and The graph showing the relationship with the volume resistivity of the ink sheet, Figure 6, is kerf 1? A graph showing the relationship between the surface area of the black ink sheet and the electrical conductivity of the ink sheet, FIG. FIG. 9 is a schematic diagram showing two sides of the multi-stylus. 1... Recording material for electrical transfer (ink sheet) 2...
Recording body 3...Recording needle 3', ! ...Multi-stylus 4.4'...Return electrode 5...Distributed applied voltage 6...Recording current 7, 7/, 7''...Thermal transfer ink 8...Support roller 11... Base layer 12... Ink layer 25-5 Ryo 1 Figure 2 Figure 4 Figure 3 (A) 3 4 (D) - 12) 1.

Claims (1)

[Claims] 1. Arrange the recording material and the recording material for electrical transfer in an 8-ply arrangement 7a, contact the return electrode with the recording material, and contact the recording material surface with the self-recording pole needle to apply a voltage to the recording material. L/
c The recording medium used in the current transfer recording method in which an electric current is applied to transfer ink onto the recording medium has a surface area of 200y&/,! The main components are carbon black with a temperature of i7 or higher and a binder component with a melting point or softening point of 150°C or higher, and the volume Ili! IJ resistance 10-1~102ΩCm
The paste has a thickness of 5 to 30 μm and a surface area of 200 m.
The main component is carbon black with a temperature of /E or higher and a binder component with a melting point or softening point of 50 to 200°C, and a multilayer ink with a volume resistivity of 10-2 to 10'Ω and a thickness of 1 to 30 μm. A recording material for electrical transfer, characterized in that the resistance of the ink layer and the resistance of the paste layer are relatively low.