JPS609915B2 - discharge recording material - Google Patents

Description

[Detailed description of the invention] The present invention relates to a discharge recording material.

In recent years, information has become extremely abundant, and the need for prompt transmission and recording of that information has increased, and various developments have been made regarding information management systems such as information processing systems, information transmission systems, and information recording systems. A typical example is a discharge recording system. A discharge recording system applies an electrical signal of several hundred volts or several watts to a recording needle in the form of voltage, and the generated discharge destroys the semiconductive recording layer on the surface of the recording material. This method forms an image on itself or on a substrate laminated to the recording layer.This method is widely used as a simple recording method that does not require operations such as development and fixing, and is used for example in facsimile and various measurement methods. It is used for recording devices, recorders, displaying records in computers, and making plates for electronic recording mimeographs.

As mentioned above, in discharge recording, a discharge recording needle is brought into direct contact with the recording side surface of a discharge recording material, and an electric discharge is generated from the recording needle to destroy the recording layer and form an image. During discharge breakdown, a bad odor or soot is generated, or a colored substance such as carbon black dispersed in the recording layer is scattered. These soot and carbon black adhere to the recording material and contaminate it, or adhere to the discharge recording needle and impede accurate discharge, causing a decrease in recording reliability.

Furthermore, in discharge recording, since the discharge recording needle is scanned by directly contacting the recording material, it has the disadvantage that scratches from scanning traces remain on the recording material, impairing its natural appearance.

In order to solve the above-mentioned drawbacks, the present inventors have developed a discharge recording material having a three-layer structure in which a semiconductive resin layer and a conductive layer are laminated in this order on a metal-containing resin layer made of metal powder and a resin matrix. proposed. When discharge recording is performed by placing a recording needle on the metal-containing resin layer of this discharge recording material and touching paper under the conductive layer, there is no release of bad odor, soot, carbon black, etc. to the surroundings, and "discharge transfer recording" The accuracy was very good, and a clear, natural-looking image with soft tones and dark colors was obtained, but it had the disadvantage that image density decreased when discharge transfer recording was performed multiple times, that is, the rigidity was not good. In addition, the conductive layer has low mechanical strength and may be damaged during storage or transportation.An object of the present invention is to provide a discharge recording material that does not have the above-mentioned drawbacks, and to improve discharge recording. The recording material itself or the discharge recording device may be contaminated by the occurrence of a foul odor, the scattering of colored substances such as soot or carbon black, or the accuracy of discharge recording may be reduced due to the adhesion of colored substances such as soot or carbon black to the discharge recording needle. It is a discharge recording material that can produce clear, natural-looking and soft recorded images without any problems such as problems, and the conductive layer is protected and there is no risk of damage during storage or transportation. An object of the present invention is to provide a discharge recording material with good sakaki resistance that does not deteriorate.

That is, the gist of the present invention is a laminate having a four-layer structure,
The first layer consists of a metal powder and a resin matrix, the metal powder occupies 5 to 6% of the main volume, and the surface resistance is 1 to 1 to 60.The second layer is a metal-containing resin layer. It consists of a conductivity imparting agent and a resin matrix, and has a surface resistance of 1 to 1.
and 60: 'C' A conductive layer whose third layer has a surface resistance of 1 and Q or less: and ■ A fourth layer whose surface resistance is 1 or less and a conductive layer whose surface resistance is less than or equal to the surface resistance of the conductive layer. A discharge recording material characterized in that the protective layer is larger than the resistance and has a thickness of 10 layers or less, and is laminated in the above order.

The resin matrix used in the present invention is preferably a thermoplastic resin as long as it has film-forming ability and electrical insulation properties.

The above-mentioned thermoplastic resins generally have a high binding strength for metal powders, conductivity imparting agents, inorganic fillers, etc., and have high mechanical strength when molded into a sheet or film, are flexible, and have strong stiffness. For example, polyethylene, polypropylene, polyvinyl chloride, polyvinyl acetate, ethylene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer, polystyrene, polyacrylonitrile, polyvinyl acetal, polyacrylic acid alkyl ester, polymethacrylic acid, etc. Alkyl esters are also po-IJ esters, cellulose acetate is polyvinyl alcohol to carboxymethyl cellulose, gelatin, etc. Polyethylene ~ polyvinyl chloride to vinyl chloride - ethylene copolymer, vinyl chloride vinyl chloride copolymer ~ polypynylacetal is also cellulose acetate The resin matrices of each of the metal-containing resin layer, semiconductive resin layer, conductive layer, and protective layer may be of the same type or different types. .

The metal powder used in the present invention refers to a metal in powder form, and ``the powder must have electrical conductivity.

It is preferable to use a powder of a highly conductive metal, and specific examples of suitable metal powders include powders of copper, aluminum, iron, tin, zinc, molybdenum, silver, and the like. Metal powder coated with other metals can also be used, such as steel powder coated with silver. Of the above metal powders, copper, zinc, and iron are more preferably used.Also, the particle shape of the metal powder is resin-like,
Spherical or lump-like particles are preferable, and particles with a small and uniform particle size are preferable, with an average particle size of 0.2 to 20.
A micron one is preferable, more preferably 0.5 to 1
It is 0 micron. The metal-containing resin layer, which is the first layer in the present invention, is composed of the resin matrix and the metal powder, and the metal powder may include one or more metal powders selected from the metal powders described above. may be selectively used, and if the amount added is too small, the conductivity will become low, and if the amount added is too large, the conductivity will be too good and the current applied from the recording needle will be reduced. 5 to 6% of the main volume of the metal-containing resin layer.
The surface resistance is determined to be 1 to 1 and 60, more preferably 1 to 1 and 40.

The above-mentioned metal-containing resin layer is used as a discharge recording material, and when recording discharge, it is assisted by a discharge recording needle, so the metal-containing resin layer eliminates the risk of cracking, etc., and improves storage stability. In order to prevent the constituent substances from adhering to the recording needle and further improve the formability of the layer, a plasticizer,
Fillers, lubricants, stabilizers, antioxidants, flame retardants, etc. may be added. The conductivity imparting agent used in the present invention only needs to have conductivity, such as carbon black,
Graphite, zeolite, zinc oxide, stannic oxide, metastannic acid, ferrous steel, reduced titanium oxide, ferric oxide, and the like are preferably used.

Although the other metal powders mentioned above can also be used, it is preferable that the metal powders are used in combination with the conductivity imparting agent. The conductivity imparting agent preferably has a uniform particle size and an average particle size of 10 peaks or less. The semiconductive resin layer, which is the second layer in the present invention, is made of the resin matrix and the conductivity imparting agent, and is laminated on the metal-containing resin layer, and the conductivity imparting agent is the conductivity imparting agent. One or more of the agents may be selected and used, and the amount added may be determined so that the surface resistance of the semiconductive resin layer is between 1 and 1 and 60, and generally the resin matrix 10
It is added in an amount of 1 to 100 parts by weight per part by weight.

Further, it is preferable to add an inorganic filler to the semiconductive resin layer because it becomes a discharge recording material and an image with high density and clarity can be obtained when recorded.

Examples of the inorganic fillers include calcium oxide, magnesium oxide, potassium carbonate, sodium carbonate, calcium carbonate, strontium carbonate, titanium oxide, barium sulfate, lithopone, basic magnesium carbonate, silica, and clay. The particle size of the inorganic filler is uniform, and the average particle size is preferably 0.1 to 10 particles, more preferably 0.1 to 3.0 particles, and the amount added is 10 to 10 particles in the resin matrix. It is preferable to add 10 to 100 parts by weight per part by weight of .

In the present invention, the conductive layer is the third layer laminated on the semiconductive resin layer, and has a surface resistance of 1 pi or less, and is composed of a resin matrix and a conductivity imparting agent. It may be a metal thin film, and a metal thin film is more preferable because it can be made very thin.

As the conductivity imparting agent, the conductivity imparting agent used to form the semiconductive resin layer is used, and the amount added is determined so that the surface resistance of the conductive layer is 1 piQ or less. Generally, it is preferable to add 10 to 1000 parts by weight per 100 parts by weight of the resin matrix.

In addition, when a metal thin film is used as a conductive layer, it is necessary that its surface resistance is 1 pi or less; if the thickness is too thin, the surface resistance will be greater than 1 pi, and if it is too thick, it will cause discharge breakdown. The thickness is preferably 40 to 5000 angstroms, preferably 100 to 3000 angstroms.
angstrom, more preferably 200 to 20
00 angstroms.

Examples of metals used include aluminum, silver, gold, copper, zinc, tin, nickel, and molybdenum, with aluminum, silver, and gold being preferred. The protective layer in the present invention is a fourth layer laminated on the conductive layer, which is mainly composed of a resin matrix having a surface resistance higher than that of the conductive layer and a thickness of 10 mm or less. The resin matrix described above is used as the resin matrix. This layer is used as a discharge recording material and is destroyed by discharge together with the semiconductive resin layer and the conductive layer when discharge recording is performed.It protects the conductive layer and improves the printing durability of the discharge recording material. Therefore, it is preferable that this layer is easily destroyed by discharge, and the thickness of the layer is preferably 5 mm or less, and more preferably 4 mm or less. The surface resistance may be greater than the surface resistance of the conductive layer; preferably, the ratio of the surface resistance of the protective layer to the surface resistance of the conductive layer is 1 or more. In order to impart electrical conductivity to the protective layer, the electrical conductivity imparting agent or the metal powder may be added.

At this time, the average particle size of the conductivity imparting agent and the metal powder is not particularly limited, but is preferably 5 mm or less,
More preferably it is 21 or less. Further, it is preferable that an inorganic filler is added to the protective layer.

As the inorganic filler, the above-mentioned inorganic filler is preferably used,
The average particle size is preferably 5A or less, more preferably 2A or less. Further, the amount of the inorganic filler added is preferably 10 to 100 parts by weight based on 100 parts by weight of the resin matrix. The structure of each layer of the discharge recording material of the present invention is as described above, and the metal-containing resin layer, the semiconductive resin layer, the conductive layer, and the protective layer are laminated in this order.

When it is desired to obtain a black recorded image using the discharge recording material of the present invention, carbon black is used as a conductive layer imparting agent to form a semiconductive resin layer, and the conductive layer and protective layer are also imparted with conductivity. Preferably, carbon black is used as the agent, particularly in the protective layer, conductive carbon black is preferably used.

Further, a coloring agent may be added to the semiconductive resin layer, the conductive layer and the protective layer, in which case a colored image can be obtained. In particular, when using a conductivity-imparting agent that is not dark in color (not black like carbon black, but zinc oxide, stannic oxide, etc.), a coloring agent should be added to the above three layers or any one of the layers. Colored records other than black can be obtained by this method. Any known coloring agent can be used as the coloring agent, such as nickel yellow, titanium yellow, cadmium red, naphthol yellow, /gumanent orange, crystal violet, malacide green, etc., and the amount added is recorded. It may be arbitrarily determined based on the color, density, etc.

Note that when the colorant has conductivity, it is necessary to pay attention to the surface resistance of the semiconductive resin layer, the conductive layer, and the protective layer. The structure of each layer in the present invention is as described above,
Metal-containing resin layer t The thickness of each layer of the semiconductive resin layer and the conductive layer formed from the resin matrix and the torme conductivity imparting agent is not particularly limited. The thickness of the layer is preferably 2 to 40 mm, and the metal-containing resin layer is preferably 5 to 50 mm thick.

Furthermore, the method of forming each layer is not limited in any way, and any known method such as solution casting, emulsion casting, calendaring, extrusion, etc. may be employed.

Further, any known method may be used to form the conductive layer as a metal thin film, and for example, vacuum evaporation, ion sputtering, etc. are preferably used.

Furthermore, the method of laminating each layer is not limited at all, and the metal-containing resin layer, semiconductive resin layer, conductive layer, and protective layer may be laminated in this order by any known method.

The structure of the discharge recording material of the present invention is as described above. The discharge recording material is supplied to a discharge recording device, a discharge recording needle is placed on the metal-containing resin layer, and paper or plastic sheet is placed under the protective layer. When a recording paper such as G is discharged in parallel, the semiconductive resin layer, conductive layer, and protective layer directly under the discharge recording needle are destroyed by discharge, and recording is performed on the recording paper.

Since the metal-containing resin layer does not change in any way, soot and carbon black are prevented from scattering or adhering to the discharge recording needle during discharge recording, which reduces the hassle of maintaining the discharge recording needle. . Therefore, since soot and carbon black do not adhere to the discharge recording needle, highly reliable and clear recording can be obtained. Furthermore, since a protective layer is provided as the fourth layer, printing durability is improved, and images with high density can be obtained even after multiple discharge recordings.

Therefore, it can be used multiple times like carbon paper, and if the discharge recording material is brought into contact with the surface of the recording paper and discharge recording is performed while sending both in the same direction, discharge recording can be easily and continuously performed. Recording can be performed more economically by performing discharge recording by increasing the feeding speed of the recording paper compared to the recording material. It is also possible to record discharge by forming the discharge recording material into a ribbon shape and installing it like a typewriter.

Furthermore, if a white or light-colored conductivity imparting agent is used and a coloring agent is added to the semiconductive resin layer, conductive layer, or protective layer and discharge recording is performed, a colored image other than black can be obtained. .

Furthermore, since the protective layer covers the conductive layer, there is no risk that the conductive layer will be damaged during storage or transportation. Therefore, the discharge recording material of the present invention is suitably used for recording and displaying in facsimiles, various measuring instruments, recorders, computers, and the like. Next, examples of the present invention will be described.

Hereinafter, parts simply mean parts by weight. Examples 1 and 2
, Comparative Examples 1 and 2 Vinyl chloride-vinyl acetate copolymer 10 parts (degree of polymerization 650, vinyl acetate 13%) Electrolytic steel powder (average particle size 1.
4) 11 parts ethyl acetate
20 guo toluene
A mixture having the above composition was melted and dispersed, cast onto a glass plate, and dried to obtain a metal-containing resin sheet with a thickness of 25 mm.

The metal powder was 14.7% by volume in the sheet. Moreover, the surface resistance was 1.1×1pi30. vinylacetal resin
10 anchor parts (polymerization degree 1750, acetalization degree 67%) thermal black
12 Calcium carbonate (average particle size 1.7mm) 10 Ethyl alcohol 10
A compound having the above composition was dissolved and dispersed, coated on the sheet and dried to form a semiconductive resin layer with a thickness of 8 mm, thereby obtaining a composite sheet with a thickness of 33 mm.

The surface resistance of the semiconductive resin layer was 0.6×1 and IQ. Next, apply 6×10-5 to the semiconductive resin layer of the composite sheet.
Vacuum deposited aluminum under Torr conditions to a thickness of 40
A conductive layer with a thickness of 0 angstrom is formed to form a discharge recording material A.
(Comparative Example 1) was obtained.

The surface resistance of the conductive layer was 20.

Vinyl acetal resin 10 anchors (degree of polymerization 1750, degree of acetalization 67%) Acetylene black 8 base ethyl alcohol
Next, a compound having the above composition was dissolved and dispersed, coated on the surface of the conductive layer of the discharge recording material A, and dried to form a protective layer with a thickness of 3 mm, 6 mm, and 12 mm, thereby producing free recording. Materials B (Example 1), C4 (Example 2) and D (Comparative Example 2) were obtained.

The surface resistance of the protective layer was 1.2×1 pi. The obtained discharge recording materials A and B were supplied to a facsimile receiver (manufactured by Matsushita Denshu Co., Ltd., trade name: Panafax 100 trays), and high-quality paper was brought into contact with the conductive layer or the protective layer under the scanning line density of 4.
The same image was discharge-recorded five times under the conditions of the i/side.

During discharge recording, there was no scattering of soot or carbon black, almost no bad odor, and no through holes were formed in the metal-containing resin layer, and a clear black image was obtained on the high-quality paper. The density of the obtained image is shown in FIG. Further, when discharge recording was performed in the same manner using the obtained discharge recording materials C and D,
With discharge recording material C, an image with a density of 0.60 was obtained, but
No image was obtained with discharge recording material D. Example 3,
4. Comparative Example 3 Vinyl acetal resin 10 parts (degree of polymerization 175u, degree of acetalization 67%) Thermal black 16 parts Minor calcium carbonate (average particle size 1.7〃) 100 parts ethyl alcohol
A compound having the above composition was dissolved and dispersed, applied and dried on the metal-containing resin sheet obtained in Example 1 to form a semiconductive resin layer with a thickness of 20 mm, and a semiconductive resin layer with a thickness of 45 mm. A composite sheet was obtained.

The surface resistance of the semiconductive resin layer was 5×1 pi○. A conductive layer was formed by vacuum-depositing aluminum to a thickness of 400 angstroms on the semiconductive resin layer of the composite sheet in the same manner as in Example 1, to obtain discharge recording material E (Comparative Example 3). . The surface resistance of the conductive layer was 30.
Vinyl butyral resin 10 parts (polymerization degree 1700, butyralization degree 65%) Thermal black
20 Ikarikaku ethyl alcohol
Discharge recording materials F and 100 parts of the present invention were prepared by dissolving and dispersing the composition having the above composition, coating and drying the mixture on the conductive layer of the discharge recording material E to form protective layers with thicknesses of 3 and 8 mm, respectively. I got a G.

The surface resistance of the protective layer was 0.8×1 piQ. When the obtained discharge recording materials E, F and G were discharge recorded in the same manner as in Example 1, the same image was recorded five times for E and F and once for G, there was no scattering of soot or carbon black. There was almost no bad odor, and a clear black image was obtained on the high-quality paper without forming any through holes in the metal-containing resin layer.

The densities of images obtained from discharge recording materials E and F are shown in FIG. Also, the image density obtained from discharge recording material G is 0.
．． It was 43.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the relationship between the number of discharge recordings and the density of the obtained image. In the figure, A, B, E and F are discharge recording materials A, B, respectively.
The results of E and F are shown. Figure 1

Claims (1)

[Scope of Claims] 1. A laminate having a four-layer structure, wherein (A) the first layer is made of metal powder and a resin matrix, the metal powder accounts for 5 to 60% by volume, and the surface resistance is 10
Metal-containing resin layer having a resistance of ＾5 to 10＾1＾6Ω; (B)
The second layer consists of a conductivity imparting agent and a resin matrix,
A semiconductive resin layer with a surface resistance of 10^5 to 10^1^6 Ω; (C) the third layer is a conductive layer with a surface resistance of 10^4 Ω or less; and (D) the fourth layer is a resin matrix. What is claimed is: 1. A discharge recording material comprising: a protective layer having a surface resistance greater than that of a conductive layer and a thickness of 10 μm or less, which are laminated in the above order. 2. The discharge recording material according to claim 1, wherein the metal powder has an average particle size of 0.2 to 20 μm. 3. The discharge recording material according to claim 1, wherein the conductivity imparting agent is carbon black. 4. The discharge recording material according to claim 1, wherein the conductive layer is a metal vapor deposited film. 5. The discharge recording material according to claim 4, wherein the metal deposited film is an aluminum deposited film. 6. The discharge recording material according to claim 1, wherein the conductive layer comprises a conductivity imparting agent and a resin matrix. 7. The discharge recording material according to claim 1, wherein the ratio of surface resistance between the protective layer and the conductive layer is 10^2 or more. 8. The discharge recording material according to claim 1 or 7, wherein the protective layer comprises a resin matrix and carbon black. 9 Claim 1 in which the thickness of the protective layer is 5μ or less
8. The discharge recording material according to item 7, item 8.