JPH0673818B2 - Method for manufacturing thin blade rotary whetstone for cutting - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is mainly used in the field of dentistry to rotate thin blades used for grooving adjacent surfaces of prostheses and for cutting teeth and prostheses. Regarding the whetstone.

(Prior Art) A thin blade rotary grindstone used for dental treatment is attached to a holder 31 and then mounted on a dental engine for use as shown in FIG.

As the rotary grindstone 32, as shown in FIG.
Diamond super-abrasive grains 43, 43 ...
Are dispersed and a part thereof is projected from the opposite surface 44, and as shown in FIG. 4 (b), two rotary grindstones 32, 32 'shown in FIG. 4 (a) are provided. A structure in which flat surfaces 411 and 41 'are joined to each other is shown in JP-A-63-11281.

The rotating grindstone shown in FIG. 4 (a) has superabrasive grains 43, 4 on the surface 44.
3 protrude, but on the back surface 41, the superabrasive grains 43, 43 ... Do not protrude at all and form a flat metal surface. Therefore, the cutting function is low, and the cutting line is curved toward the surface 44 and cannot be cut straight. Further, on the back surface 41 side, coloring occurs due to metal adhesion to the tooth, the porcelain, or the porcelain to be cut and cut.

The rotary grindstone shown in FIG. 4 (b) is intended to improve the drawbacks of the rotary grindstone of FIG.
Since the content of superabrasive grains is small near 1,41 ', the metal at the bonding interface 41,41' protrudes at the periphery of the grindstone during cutting work, which reduces the cutting function and causes the protruding metal to color the ceramic teeth. To do In addition to this, the bonding interfaces 41, 41 'are likely to peel off.

In view of the above problems, the present invention intends to realize a rotary grindstone that can maintain a good cutting function for a long period of time, has no coloring due to the adhesion of metal to a cut surface, and has a small curvature of a cutting line. It is a thing.

(Means for Solving the Problems) In the present invention, a conductive flat substrate on which superabrasive particles are deposited is placed in a plating solution, or superabrasive particles are formed on the conductive flat substrate in the plating solution. After depositing, by depositing a metal, a step of fixing the superabrasive grains on the substrate is carried out, and then a step of peeling a layer composed of the superabrasive grains and the deposited metal from the substrate, carry out. These two steps are almost the same as the conventional method for manufacturing a rotary grindstone shown in FIG.

As a feature of the present invention, the surface of the first metal layer containing the superabrasive grains obtained as described above, which was in contact with the substrate, is etched to remove a part of the deposited metal. A step of exposing a part of the superabrasive grains and depositing the superabrasive grains again on the etched surface of the first metal layer and placing them in a plating solution, or by performing the above etching in a plating solution. After depositing superabrasive grains on the surface that has been subjected to
Performing a step of fixing the deposited superabrasive grains on the etched surface of the first metal layer by depositing the second metal layer.

The means of etching include chemical corrosion, electrolysis,
Appropriate things such as electric discharge machining and sand blast can be adopted.

(Operation) In the rotary grindstone obtained by the present invention described above, the surface of the first metal layer on the flat side having a large amount of metal has a portion of the metal removed by etching, and another superabrasive grain is formed thereon. It is fixed by the second metal layer. Therefore, at the bonding interface between the first metal layer and the second metal layer, the superabrasive grains of both layers are in mesh with each other, and the amount of metal is not much different from the other parts,
The whole grindstone has a uniform structure.

As a result, it is possible to effectively prevent the bonding interface from protruding at the peripheral edge portion of the grindstone and impairing the cutting function during the cutting operation, and the separation of both metal layers at the bonding interface.

(Example) As shown in FIG. 1 (a), the surface of a stainless steel flat substrate 1 having the same diameter as that of a grindstone to be manufactured is polished with water-resistant abrasive paper No. 600 or more so that it can be easily peeled off. After that, masking coating 2 is applied to the surface, the peripheral edge and the central hole portion, degreasing and cleaning is performed, and the plating solution is put into the plating solution, superabrasive grains 3 are deposited on the substrate 1, and metal is deposited using the substrate 1 as a cathode. The superabrasive grains 3 are fixed to the substrate 1 by the deposited metal layer.

By peeling the deposited metal layer 4 containing the super-abrasive grains 3, 3 ... From the substrate 1, the central hole 5 as shown in FIG.
A disk-shaped intermediate product 6 having is obtained. In this intermediate product 6, the surface 6a in contact with the substrate 1 is smooth, and the superabrasive grains 3, 3 ... Are embedded in the deposited metal layer 4, but the opposite surface 6b is
A part of the superabrasive grains 3, 3, ... Project from the deposited metal layer 4.

When the surface 6b of the intermediate product 6 from which the superabrasive grains are projected is masked and then the smooth surface 6a is etched, the metal of the smooth surface 6a as shown in FIG. Are eroded, and the superabrasive grains 3, 3 ... Become rough surfaces 6a ′ protruding from the metal layer 4.

Then, superabrasive grains 7, 7 ... Are deposited on the rough surface 6a ′ by the same method as described with reference to FIG. 1 (a), and electricity is applied in the plating solution. As shown in (1), a rotary grindstone in which superabrasive grains are further fixed on the intermediate product 6 can be obtained.

The cross section of this rotary grindstone has a structure in which a metal layer 4 containing superabrasive grains 3,3 ... And a metal layer 8 containing superabrasive grains 7,7 ... Has become. At the bonding interface 9, a part of the superabrasive grains 3,3 ... protruding from the metal layer 4 is eroded in the metal layer 8, and in the metal layer 8, between the superabrasive grains 3, 3 ,. The shape is such that superabrasive grains 7,7 ...

Therefore, since the grinding performance on both sides of the rotary grindstone is completely the same, the cutting line is not curved unlike the conventional rotary grindstone shown in FIG. 4 (a), and the superabrasive grains are projected on the entire surface. Therefore, the object to be cut is not colored. Further, since the amount of metal with respect to the superabrasive grains at the bonding interface 9 is not so large as in the rotary grindstone shown in FIG. 4 (b), the metal layer may protrude at the peripheral edge of the rotary grindstone to impair the cutting function. The object to be cut is not colored, and peeling at the bond interface is extremely unlikely to occur.

Example 1 A stainless steel disk having a diameter of 19 mm was used as the substrate 1, and 600
After polishing with a # 1 or more water-resistant abrasive paper, apply masking coating 2 on the surface, peripheral edge, and center hole, and then superabrasive grains 3 under the following conditions.
Was fixed to the substrate 1.

Plating bath NiSO ₂・ 6H ₂ O 330g / l NiCl ₂・ 6H ₂ O 60g / l H ₂ BO ₃ 42.1g / l Bit inhibitor Some brightener Some pH 4.5 Temperature 45 ℃ Super abrasive grain Diamond grain size 30-40μm Current density 2A / dm ² plating time 120 minutes As described above, the nickel metal layer 4 was deposited on the substrate 1 to a thickness of about 0.06 mm, and two layers of superabrasive grains were fixed to the substrate 1.

The nickel metal layer 4 is peeled off from the substrate 1, masking is applied to a required portion, and then the projection of the superabrasive grains 3, 3, ... on the smooth surface 6a is visually observed in the ferric chloride solution (35 ° Baume). It was immersed until it was possible, and etching was performed.

The same superabrasive grains as described above were fixed to this etched surface using the same plating solution under the same conditions to obtain a rotary grindstone having an average thickness of 0.15 mm.

Comparative Example 1 A substrate 1 similar to that of Example 1 was fixed with the same superabrasive grains (diamond grain size 30 to 40 μm) by plating under the following conditions using the same plating bath.

Current density 2 A / dm ² Plating time 180 minutes As described above, the nickel metal layer 4 having a thickness of about 0.09 mm was deposited on the substrate 1 and about 3 layers of superabrasive grains were fixed to the substrate 1. The metal layer containing the superabrasive grains was peeled off from the substrate 1 to obtain a sample having an average thickness of 0.1 mm.

Comparative Example 2 An intermediate product 6 was prepared under exactly the same conditions as in Example 1, and after masking coating was applied to the surface 6b from which the superabrasive grains were protruding, the smooth surface 6a was immediately subjected to the same superimposing without etching. The abrasive grains were fixed by the same method to obtain a sample having an average thickness of 0.16 mm.

Example 2 On the same substrate 1 as in Example 1, superabrasive grains were fixed by plating using the same plating bath. The superabrasive grains used and the plating conditions are as follows.

Superabrasive grains Diamond grain size 50-60 μm Current density 2A / dm ² Plating time 200 minutes As a result, a nickel metal layer 4 having a thickness of about 0.1 mm is deposited on the substrate 1, and two layers of superabrasive grains are formed on the substrate 1. Fixed to.

The nickel metal layer 4 is peeled off from the substrate 1, masked on a required portion, immersed in 10% hydrochloric acid, and electrolytically etched at a current density of 5 A / dm ² for 3 minutes. The same superabrasive grain was fixed under the same plating conditions, and a rotary whetstone with an average thickness of 0.24 mm was obtained.

Comparative Example 3 The same plating bath was used for the same substrate 1 as in Example 1, and the same superabrasive grains as in Example 2 (diamond grain size 50-60 μm).
Was fixed by plating under the following conditions.

Current density 2 A / dm ² Plating time 300 minutes As a result, a nickel metal layer 4 having a thickness of about 0.15 mm was deposited on the substrate 1 and about 3 layers of superabrasive grains were fixed to the substrate 1. The metal layer containing the superabrasive grains was peeled from the substrate 1 to obtain a sample having an average thickness of 0.18 mm.

Comparative Example 4 An intermediate product 6 was produced under exactly the same conditions as in Example 2, and after masking coating was applied to the surface 6b from which the superabrasive grains were protruding,
The same superabrasive grains were immediately fixed by the same method without etching the smooth surface 6a to obtain a sample having an average thickness of 0.26 mm.

The following table shows the results of a comparative test in which five sample grindstones were manufactured according to each of the above-mentioned examples and comparative examples. In this,
As for the cutting property, porcelain material of 5 mm × 5 mm × 30 mm was used as the cut object, and the sample grindstone was rotated at 12000 rpm and the force of 50 gf was applied.
The average length that can be cut in a minute is shown. The coloring property is indicated by how many of the five samples produced coloration on the cut object during the above cutting test. Peelability is 15000 rpm rotation and 100 g
The force of f is given and the free-hand grinding test is performed for 20 minutes, and it is shown by how many of the five samples caused delamination.

(Effect of the invention) As is clear from the above description, the rotary grindstone according to the present invention has excellent cutting performance, and this cutting performance can be maintained until the grindstone wears down to a small diameter, and there is no distortion of the cutting line. It does not give coloring to the object to be cut, does not cause delamination during use, and completes various conditions required for a dental cutting wheel.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing a process of the present invention, FIG. 2 is an enlarged sectional view of a grindstone according to the present invention, and FIG. 3 is a side view showing a state of use of a cutting rotary grindstone. FIG. 4 is an enlarged sectional view of various conventional cutting wheels. 1 ... Substrate, 3 ... Superabrasive grains, 4 ... First metal layer, 6a ... Surface that was in contact with the substrate, 7 ... Superabrasive grains, 8 ... Second metal layer.

Claims (1)

[Claims] 1. A step of fixing the superabrasive grains on the substrate by depositing a first metal layer on a conductive flat substrate on which the superabrasive grains are deposited in a plating solution; A step of peeling the first metal layer containing grains from the substrate, and etching the surface of the peeled first metal layer in contact with the substrate to remove the deposited metal until the superabrasive grains are exposed. The step of removing the superabrasive grains is performed by depositing the superabrasive grains again on the etched surface of the first metal layer and precipitating the second metal layer in the plating solution. And a step of fixing the metal layer to the above-mentioned etched surface.