JPH0775050B2 - Magnetic head glass filler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention fills between divided magnetic materials in order to form a core of a magnetic head used in a VTR [video tape recorder] or the like. The present invention relates to a glass filler for welding materials.

[Prior Art] A core of a magnetic head such as a VTR is formed by facing each other through a thin film of a non-magnetic material for forming a gap between blocks of a magnetic material divided into two, and welding with a glass filler. There is.

As the glass filler, lead-boric acid-based low melting point glass has been conventionally used so that the welding work can be performed at a relatively low temperature.

[Problems to be Solved by the Invention]

However, the lead-boric acid-based low-melting-point glass that has been conventionally used has properties of poor acid resistance and water resistance. Therefore, for example, if dew condensation occurs on a magnetic head such as a VTR in winter, the glass filler may be deteriorated.

Therefore, the conventional magnetic head has a problem that durability deteriorates due to the deterioration of the glass filler.

[Means for Solving the Problem] In order to solve the above problems, the glass filler for a magnetic head according to the present invention is made of a magnetic material that is divided in order to weld a magnetic material to form a core of the magnetic head. In the glass filler for the magnetic head made of lead-boric acid-based low-melting-point glass filled in between, 0 for improving acid resistance and water resistance.
It is characterized in that 1 to 0.2% by weight of zinc fluoride is added.

[Work]

According to the above configuration, the lead-boric acid-based low melting point glass is 0.1
~ 0.2 wt% zinc fluoride is added, so lead-
The acid resistance and water resistance of the boric acid-based low melting point glass are significantly improved. Therefore, a magnetic head using a glass filler made of such a lead-boric acid-based low-melting-point glass having improved acid resistance and water resistance is deteriorated even if dew condensation occurs in winter, for example. This is eliminated and the durability of the magnetic head is improved. The addition of 0.1 to 0.2% by weight of zinc fluoride improves the acid resistance and water resistance of the lead-boric acid-based low melting point glass because the fluororesin exhibits excellent acid resistance. For the same reason, lead-
It is considered that this is because the fluorine atom enters the network structure of the boric acid-based low melting point glass.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 9.

This example shows a glass filler used for the core of a magnetic head of a VTR. The core of this magnetic head is a composite of an oxide magnetic material having a high magnetic permeability and an alloy magnetic material having a high magnetic permeability and a high saturation magnetic flux density in order to perform high density recording on a magnetic recording medium having a high coercive force. The material is used as a magnetic material.

As shown in FIG. 1, the magnetic head and the core 1 are formed by bonding the divided magnetic body blocks 2 and 3 together.
The magnetic blocks 2 and 3 are blocks made of an oxide magnetic material having a high magnetic permeability. This magnetic block 2
As for the surfaces facing each other, only the areas having a predetermined width are fitted to each other in the upper portion, and the sufficiently wide areas are joined to each other in the lower portion. Magnetic thin films 4 and 4 made of an alloy magnetic material are formed on the surfaces of the magnetic blocks 2 and 3 which face each other.

Thus, the magnetic body blocks 2 and 3 facing each other with the magnetic thin films 4 and 4 interposed therebetween are further in close contact with each other via a non-magnetic thin film made of a non-magnetic material (not shown). Therefore, the portion of the upper portion, which is joined with a predetermined width, is the gap 5 through the non-magnetic thin film.
Will be formed.

The gaps other than the combined portions of the magnetic blocks 2 and 3 are filled with the glass fillers 6 and 6 except for the holes through which the windings pass. The glass fillers 6 and 6 are made of lead-boric acid-based low melting point glass to which 0.2% by weight of zinc fluoride [ZnF ₂ ] is added. The magnetic blocks 2 and 3 are welded to each other by the glass fillers 6 and 6.

Next, the manufacturing process of the core 1 of this magnetic head will be described with reference to FIGS.

First, as shown in FIG. 2, an outer winding groove 7 and a glass filling groove 8 are formed in one magnetic body block 2 made of an oxide magnetic material, and further an inner winding groove 9 is formed. On the other magnetic block 3, as shown in FIG. 3, an external winding groove 7 and a glass filling groove 8 are formed. The magnetic blocks 2 and 3 are for collectively manufacturing several cores 1.

Next, as shown in FIGS. 4 and 5, the gap forming surfaces 10 and 10 and the tape sliding surface 11 of these magnetic substance blocks 2 and 3 are shown.
11 is polished into a mirror surface, and a plurality of track grooves 12 are formed on one end side of the gap forming surface 10. The gap width between the track grooves 12 and 12 is the width of the gap 5 to be formed later.

When the track grooves 12 are formed, as shown in FIG. 6 and FIG. 7, after the work-affected layer formed on the gap forming surfaces 10 of these magnetic substance blocks 2 and 3 is removed by etching, Magnetic thin films 4 made of an alloy magnetic material are formed on the surface by a sputtering method. In addition, a non-magnetic thin film made of SiO ₂ or the like is formed on the magnetic thin film 4 of the one magnetic substance block 2 or the magnetic substance block 3 thus formed by about 0.3.
It is formed to a thickness of μm. The thickness of this non-magnetic thin film is the gap length of the gap 5 to be formed later.

When the non-magnetic thin film is formed, as shown in FIG. 8, these magnetic blocks 2 and 3 are pasted with the gap forming surfaces 10 and 10 facing each other, and the glass filling groove 8 and the internal winding groove are formed. The rod-shaped material of the glass filling material 6 is arranged in 9. The rod-shaped material of the glass fillers 6 and 6 is made of the lead-boric acid-based low-melting glass to which 0.2% by weight of zinc fluoride [ZnF ₂ ] is added as described above.

When the glass fillers 6 and 6 are melted by heating in this state, the magnetic material blocks 2 and 3 are welded as shown in FIG. After that, the tape sliding surface 11 is polished to have a curvature and further cut along the two-dot chain line in the figure to complete the core 1 of the magnetic head shown in FIG.

The results of acid resistance and water resistance tests performed on the core 1 manufactured as described above and the core of the conventional magnetic head are shown below.

In the conventional core, a lead-boric acid-based low melting point glass containing no fluorine compound is used as a glass filler. Then, the core 1 of the present embodiment and the conventional core are treated with hydrogen chloride [HCl] 0.1
The state after immersion in a mol / solution for 170 hours was examined.

As a result of the test, the surface of the glass filler used for the conventional core was considerably roughened. However, the surface of the glass filler 6 used for the core 1 of this example was hardly roughened.

Therefore, if the core 1 manufactured in this embodiment is used for a VTR magnetic head, the glass filler 6 will not deteriorate even if dew condensation occurs in the winter, for example.

〔The invention's effect〕

As described above, the glass filler for the magnetic head according to the present invention has a lead-boric acid-based low melting point filled between the divided magnetic materials in order to weld the magnetic material to form the core of the magnetic head. In a glass filler for a magnetic head made of glass, 0.1 to 0.2% by weight of zinc fluoride is added to improve acid resistance and water resistance.

As a result, acid resistance and water resistance of the glass filler filled in the core of the magnetic head are improved, so that the glass filler of the present invention has the effect of enhancing the durability of the magnetic head and prolonging the life of the apparatus. .

[Brief description of drawings]

1 to 9 show an embodiment of the present invention. FIG. 1 is a perspective view of a core of a magnetic head, and FIGS. 2 to 9 are respective manufacturing processes of the core of the magnetic head. FIG. Reference numeral 1 is a core, 2 and 3 are magnetic substance blocks (magnetic material), 4 is a magnetic thin film (magnetic material), and 6 is a glass filler.

Claims (1)

[Claims] 1. A glass filler for a magnetic head comprising lead-boric acid-based low melting point glass, which is filled between divided magnetic materials so as to form a magnetic head core by fusing the magnetic material. A glass filler for a magnetic head, to which 0.1 to 0.2% by weight of zinc fluoride is added to improve the water resistance and water resistance.