JPH0224153A - Recording head stylus - Google Patents

Abstract

PURPOSE:To obtain a highly reliable and low-cost recording head of electrothermo-transfer recording system having good adhesion to a substrate, high fineness, and high durability by forming an electro-deposit layer of a composite-plated layer including hard and wear-resistant particles mixed therein and also having a specific thickness. CONSTITUTION:An electrorecording stylus is made of two layers. Namely, a lower layer for improving an adhesive strength between an upper layer metal and a ceramic substrate is formed by a vapor deposition or electroless plating. An upper layer part playing an intrinsic role of a recording stylus is formed by an electrolytic plating method. However, particularly a composite electrolytic- plating is applied by dispersing hard and wear-resistant particles in such a metal as nickel, cobalt-chromium, and nickel-cobalt. The hard and wear-resistant particles, such as tungsten carbide, silicon carbide, boron nitride, titanium oxide, boron carbide, chromium carbide, diamond, PTFE(polytetrafluoroethylene), and the like, can be used. In addition, the electro-deposit layer is 5-25 microns in thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a recording head for a printing device using an electrically conductive thermal transfer recording method.

<Conventional Technology> In recent years, output printers in electronics-related fields have made remarkable progress, and the quality required for them has been increasing year by year. Especially for non-impact printers, full color,
There are great expectations for gradation reproduction, etc.

There are several printing methods for non-impact printers, such as a single laser method, an inkjet method, a thermal method, an electric thermal method, a thermal transfer method, a sublimation transfer method, and an electrostatic method. Among these, the current thermal method does not generate heat in the head compared to the thermal transfer method, so there is no need to provide a cooling cycle, and the printing speed can be increased. Furthermore, by adjusting the amount of electricity, gradation printing is possible, resulting in high image quality and
Highly reliable printing is expected.

The principle of this current-heat-sensitive recording method is that the transfer film has a resistive layer and a melting ink layer, and the recording head is brought into contact with the resistive layer, and by applying a voltage to the recording needle (stylus), the resistive layer is energized. Then, the resistance layer is heated by Joule heat, and the ink is melted and transferred to the recording paper, thereby printing.

A conventional current-carrying thermal transfer recording head has a plurality of fine line patterns formed on a ceramic substrate such as alumina or forsterite, and made of a hard metal material such as tungsten, molybdenum, or molybdenum-manganese.

As a method for forming a thin line pattern recording needle (conductive layer),
Conventionally, a tungsten film or the like is formed on a ceramic substrate by vapor deposition, and then a thin line pattern is formed by photoetching, laser processing, etc. to form a head.Alternatively, a tungsten paste is printed on the ceramic substrate in a thin line pattern by screen printing. Methods etc. have been reported.

Increasing the film thickness by vapor deposition is disadvantageous in terms of production efficiency, and it is practically impossible to form a film thickness of 10 microns or more by this method. Furthermore, the adhesion strength between the ceramic substrate and the tungsten film, etc. is low, resulting in a lack of reliability as a recording head, and high manufacturing costs.

On the other hand, the latter method of forming a film of tungsten or the like on a ceramic substrate using the screen printing method has the disadvantage that the edges are disordered, especially in the case of thin lines, the lines become broken lines. In addition, in screen printing, whether the material of the plate is stainless steel, nylon, or Tetron, it is a so-called mesh (rope), so if you apply strong pressure on a stage etc., the mesh will inevitably stretch and the lines will deform during printing. occurs,
The shape of thin wires of 50 to 100 microns or less is difficult.

Therefore, screen printing naturally has its limits in terms of fineness.

<Problems to be Solved by the Invention> The present invention attempts to solve the above-mentioned problems, and provides an electrically conductive thermal transfer that has good adhesion to a substrate, high density, durability, high reliability, and low cost. The purpose is to provide a recording method.

Means for Solving the Problems The present invention provides a conductivity recorder comprising at least two layers, a metal vapor deposition layer and an electrolytic plating layer, and an electrically conductive heat-sensitive recording head having a desired shape of an insulating protective layer on an insulating substrate. , a stylus for an electrically conductive heat-sensitive recording head, characterized in that the electrolytic plating layer has a thickness of 5 to 25 microns, and the electrolytic plating layer is a composite plating layer in which hard and wear-resistant particles are mixed. It is.

The gold aX deposited film used here is one of nickel, copper, tin, nickel-chromium, silver, silver-palladium, or zinc, and its thickness is 500 to 120 mm.
Nickel-phosphorus, nickel-boron, nickel-cobalt, nickel-cobalt-nitrogen, nickel-cobalt-phosphorus, nickel-iron-phosphorus, nickel can be used instead of metal vapor deposition films, which can be about 0 angstroms. Electroless plating layers of -tungsten-phosphorus, cobalt, cobalt-phosphorus, cobalt-nickel-phosphorus, cobalt-tungsten can also be used.

One of the features of the present invention is that the conductive recording needle consists of two layers. In other words, the lower layer is provided to improve the adhesion strength between the upper metal layer and the ceramic substrate.
Formed by vapor deposition or electroless plating. The upper management is supposed to be the recording needle;! +, and is formed by electrolytic plating. On the other hand, since wear resistance is required for the upper layer, even electrolytic plating can be performed using nickel, cobalt, etc.
Examples of such hard and wear-resistant particles include tungsten carbide, silicon carbide, boron nitride, Examples include titanium oxide, boron carbide, chromium carbide, diamond, and PTFE (polytetrafluoroethylene).

Note that as the insulating substrate for the recording head of the present invention, oxide ceramics such as forsterite, steatite zircon, mullite, cordierite, zirconia, and titania are used.

This recording head is produced, for example, through the following steps.

(1) After spin-coding a photoresist on a forsterite substrate, exposure and development are performed to obtain a resist pattern.

(2) A metal vapor deposition film such as nickel is formed on the entire surface of the non-image area of the resist.

(3) Obtain a pattern using a metal vapor deposited film by dissolving and peeling off the photoresist.

(4) 40% for the purpose of increasing the adhesion strength between the metal vapor deposited film and the substrate.
Firing is carried out in a hydrogen/nitrogen mixture at a temperature of 0 to 1350 degrees.

(5) Form an electrolytic composite plating (for example, nickel-tungsten carbide) film of 5 to 25 microns on the vapor deposition pattern.

(6) An m-edge protective film is formed on the thin line pattern in order to prevent insulation failure due to adhesion of abrasion metal powder generated during printing.

Effect> In the present invention, the conductive layer that becomes the recording needle has a two-layer structure of a metal vapor deposition layer and an electrolytic plating layer, but the pattern accuracy of the conductive layer is improved by patterning the lower thin metal vapor deposition layer, By forming the upper layer by electrolytic plating, the recording needle formation speed can be increased. Moreover, by mixing hard particles such as tungsten carbide or silicon carbide in the upper electroless plating layer, the hardness and wear resistance of the recording needle are improved and the life of the recording head is extended.

<Effects of the Invention> The present invention is as described above, and by employing electrolytic composite plating in which hard particles are mixed in the conductive layer that becomes the recording needle, the hardness and wear resistance of the recording needle can be improved. This results in a significantly improved recording head with a long life. Further, by forming a lower vapor deposition layer or an electroless plating layer, the adhesion strength of the dispersed plating layer to the ceramic can be significantly improved.

From the viewpoint of productivity, since the upper layer is electrolytically plated, the recording needle formation speed can be increased and the recording needle film thickness can be stabilized, compared to when the entire layer is electroless plated. Furthermore, electrolytic plating is easier to obtain anisotropic plating than electroless plating, and is advantageous for finer plating patterns.

The present invention will be explained in more detail with reference to Examples.

[Example 1] As a substrate material, a forsterite substrate with a thickness of 0.7
all, with a center line average surface roughness of 0.3 m,
A pattern is formed on the substrate using a UV-degradable positive resist, a nickel vapor deposited film with a thickness of about 500 nm is formed on the pattern, and the vapor deposited pattern corresponding to the recording needle and wiring portion is created by peeling off the deposit film. As the zeroth step, a nickel-tungsten carbide (tungsten carbide, 4% by volume) composite plating film was electrodeposited to a thickness of 18 to 20 μm using the nickel vapor deposited film as a core. The plating profile is Watt's profile, and the profiles are: nickel sulfate 240 [g/mm, nickel chloride 40 [g/II], boric acid 30 [g/II]
II, tungsten carbide 22 [g/IJ
, the average grain size of tungsten carbide is 0.7
It is μm. The operating conditions were pif5.0.

The liquid temperature is 50°C and the current density is less than 3A/dm.

Next, a borosilicate glass insulating protective film was formed on the composite plating film. As a result of printing tests with this recording head,
The product had a long lifespan without causing insulation failure due to abrasion with the transfer paper.

[Example 2] As a substrate material, a forsterite substrate with a thickness of 0, . 9
wm center line average surface roughness of 0.2 μm Using this material, a pattern was formed on the substrate using an IIV degradable positive resist, and an electroless nickel-phosphorus coating was formed in the non-image area of the resist to a thickness of 1 μm. . After removing the resist,
Ni-5iC (SiC; 5% by volume) with plating film as core
A printed IT scratch was obtained by electrodepositing a composite plating film to a thickness of 15 to 17 μm. The plating edge is along Lewis Berb, and the alignment is nickel sulfate 240 [g/II, nickel chloride 45 [g/II, boric acid 35 [g/II sulfuric acid nia/l/] 15 (g/II, formic acid diy/l/). 'r
45-601 g/l], formalin 10 [g/l]
Silicon carbide is 3° [g/II. The average particle size of silicon carbide is 0.6 umT! Al,
m cropping property ctpH 4.0, liquid crystal 50'C1t flow density 4
A/da''.

As the next step, a polyimide insulating protective film was formed on the printing electrode to obtain a head. As a result of printing with this recording head, the product had a long life without causing insulation failure due to abrasion with the transfer paper.

[Example 3] Thickness of forsterite substrate as substrate material: 0°Bam
Using a substrate with a center line average surface roughness of 0.2 pm, a pattern was formed on the substrate using a Uv decomposition type resist, and electroless copper plating was formed on the non-image areas of the resist to a thickness of 1.5 μm. After removing the resist, apply 10% of chromium-chromium carbide composite plating film (chromium carbide 5% by volume) using the plating film as a core.
Printed electrodes were formed by electrodeposition to a thickness of ~11 μm. The linear composition is 250 [g/II] of chromic anhydride, 2.5 fg/m of sulfuric acid, and 2 [g/I] of chromium carbonate, and the average particle size of the chromium carbide is 1.5 μm. The operating conditions were a liquid temperature of 50 ("c") and a current density of 20 to 60 [^/
Anode material antimony (7z) lead alloy, voltage 1
It is 0V.

The next step is to insulate the printing electrode with borosilicate glass! !
A film was formed. A printing test was conducted using this recording head at 3.5 Hz, and the results showed that the product had a long life without causing any abrasion with the transfer paper.

Patent applicant Toppan Printing Co., Ltd. Representative: Kazuo Suzuki

Claims (5)

[Claims] (1) In an electrically conductive heat-sensitive recording head having a conductivity recorder consisting of at least two layers, a metal vapor deposited layer and an electrolytic plated layer, and an insulating protective layer of a desired shape on an insulating substrate, the thickness of the electrolytic plated layer is 5 to A stylus for a recording head having a thickness of 25 microns and characterized in that the electrolytic plating layer is a composite plating layer in which hard and wear-resistant particles are mixed. (2) Instead of a metal vapor deposition layer, use nickel-phosphorous, nickel-boron, nickel-cobalt, nickel-cobalt-boron, nickel-cobalt-phosphorous, nickel-iron-phosphorus, nickel- Claim (1) characterized in that an electroless plating layer of any one of tungsten-phosphorus, cobalt, cobalt-phosphorus, cobalt-nickel-phosphorus, cobalt-tungsten-phosphorus, copper, silver, gold, and palladium is used. A stylus for the recording head described in . (3) The matrix metal forming the electrolytic composite plating layer is
The stylus for a recording head according to claim 1, wherein the stylus is made of nickel, cobalt, chromium, or nickel-cobalt. (4) The hard and wear-resistant particles in the electrolytic plating layer are at least one selected from tungsten carbide, silicon carbide, boron nitride, titanium oxide, boron carbide, chromium carbide, diamond, and PTFE (polytetrafluoroethylene). A stylus for a recording head according to claim (1). (5) The stylus for a recording head according to claim (1), wherein the material of the metal vapor deposition layer is nickel, copper, tin, nickel-chromium, silver, silver-palladium, or zinc.