JPS61104307A - Production of magnetic head - Google Patents

Abstract

PURPOSE:To attain an accurate track width by etching the surface of a part other than the part near a magnetic gap after forming a magnetic core including a magnetic gap having a prescribed track width. CONSTITUTION:A front gap part 2 and a winding window part 3 are worked on a core 1 consisting of 'Sendust(R)' materials as shown in the figure. The part near the front gap part is coated with an acid resistant resist to form a resist part R. A bar part 5a of a jig 5 is inserted to the winding window part 3 to etch the core 1. At this time, individual cores 1 are separated from one another by spacers 5b and are pierced by the bar part 5a, and they are etched at 60+ or -5 deg.C with an etching liquid 4 where pure water is added to 10% phosphoric acid. The core is provided with a winding after the resist part R is peeled with a solvent, and the core is stuck to a base, and the part to be brought into contact with a tape is polished into a specular surface with a lapping tape or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method of manufacturing a magnetic head having a magnetic gap with a narrow track width, that is, a narrow gap length, which corresponds to high-density recording on a medium.

[Prior art]

Recently, it has been used in magnetic heads for VT)L video signals, rotary heads for PCM audio signals, etc.

As high-density recording on recording media progresses, track widths also become narrower, from about 60 μm to 30 μm or less, and gap widths also become narrower, for example, from about 0.6 μm to 0.4 μm. As a result, it has become necessary to reduce the width of the magnetic core of a magnetic head, for example from about 150 μm to 30 μm or less. When such precision machining is required, it is necessary to accurately determine the machining dimensions, and at the same time, it is necessary to consider a method for preventing deterioration of electromagnetic conversion characteristics due to machining.

As a method for preventing property deterioration due to these processing steps, the first K
The first method is to perform strain-free processing, and the second method is to remove the processing fatigue layer by etching.

Thirdly, a method has been proposed in which the machining fatigue layer is recovered by heating.

However, each of the above methods has the following drawbacks. That is, first, the first method has a slow processing speed. In addition, in the second method, the track width cannot be accurately determined because the gap length or track width of the front gap changes when etching is performed. Furthermore, in the third method, if the left and right cores are heated after they are butted together, they will shift in the track width direction.

There was a problem in that the track width varied.

〔the purpose〕

The present invention has been made in view of the above-mentioned problems, and aims to provide a method for manufacturing a magnetic head that can prevent deterioration of electromagnetic conversion characteristics due to processing and can accurately determine track width. .

〔Example〕

In this embodiment, prior to using the second etching method described above, the front gap portion is coated with a resist so as not to change in size due to etching, and then the entire head is etched. in this case,
When the surface facing the tape is also etched, in the final step 3, the surface facing the tape is mirror-finished using wrapping tape.

This example will be described below based on the drawings. 1 to 3 are process diagrams showing one embodiment of the manufacturing process of the present invention, and FIG.

FIG. 2 shows the resist coating process for the front gap portion of the core, and FIG. 3 shows the etching process for the entire core.

In the '/TR recording head of this embodiment, the core 1 made of sendust material is processed into the shape shown in FIG. In this case, for example, the track width is 28 μm, the gap is 0.4
It is assumed that the head is 28 μm and the thickness of the core is 28 μm.

2 indicates a front gap portion, and 3 indicates a winding window portion.

Next, as shown in FIG. 2, a step is taken to cover the vicinity of the front gap portion with an acid-resistant resist.

The R portion indicates this resist portion.

Next, as shown in FIG. 3, the rod portion 5a of the jig 5 is passed through the three portions of the first winding window to perform etching.

5b is a spacer, and 4 is an etching solution. In this case, a solution (10% phosphoric acid in pure water) is used, and the temperature of the solution is 60°±5°C. In this process, the front and back sides of the head coat 1 are etched uniformly, and the amount of etching is set to 0.
It is desirable to stop with an accuracy of 5 μm, and for this purpose.

For example, it can be uniformly etched by applying ultrasonic waves.

Thereafter, the resist portion R is peeled off with a solvent, the first winding is firmly fixed to the base, and the portion in contact with the tape is polished to a mirror finish using a wrapping tape or the like to complete the entire process.

FIG. 4 is a comparison diagram of the frequency/relative output characteristics of the head A of the embodiment of the present invention described above and the head B of the conventional product, according to this embodiment.

This shows that the improvement in output is particularly remarkable in the high frequency range.

Furthermore, the manufacturing method of the present invention is particularly effective when the magnetic resistance of the core portion of the pond is large compared to the magnetic resistance of the gap portion, and when the magnetic permeability of the core portion is small and the thickness of the core portion is thin. Sometimes it is especially useful.

〔effect〕

As explained above, according to the method for manufacturing a magnetic head of the present invention, deterioration of head characteristics is prevented by etching the other portions of the magnetic core including the magnetic gap of a predetermined track width except for the vicinity of the gap portion. Not only can this be prevented, but accurate track width can now be obtained.

[Brief explanation of drawings]

1, 2, and 3 are process diagrams each showing an example of the manufacturing process of the present invention, and FIG. 4 is a frequency-relative output diagram of the head showing the effects of the present invention. . 1...Head core 2...Front gap section 4...Etching liquid 5...Jig

Claims (1)

[Claims] A method of manufacturing a magnetic head, comprising the step of, after the step of forming a magnetic core including a magnetic gap having a predetermined track width, etching the surface of a portion excluding a portion near the magnetic gap.