JPS6058805A - Edge for razor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to razor blades.

Normally, commercially available razor blades are made from stainless steel tsuba material, but in order to improve the sharpness of these stainless steel blades, we make razor blades from zirconia, which does not rust and has high hardness and toughness. It is preferable.

According to the present invention, a razor blade having a cutting edge made of zirconia is obtained.

Ceramics that can be used as materials for razor blades include alumina, zirconia, metal composite ceramics, and single-crystal alumina.The results of examining the suitability of these ceramics as materials for razor blades are as follows. As shown in Table 1.

In Table 1, in terms of the quality of the cutting edge, single crystal alumina and zirconia are the best, and when compared with single crystal alumina and zirconia, zirconia is superior in terms of toughness. In addition to zirconia, the zirconia molding material is a two-component system in which zirconia is the main component and calcium oxide, alumina, etc. are added to it.

A three-component system can also be used.

When manufacturing razor blades using this zirconia, the most important thing is that the following conditions are met.

That is, 1. Thinness z High density & homogeneity 4. Economic efficiency 5. Mass-produced razor materials need to be as thin as possible. This is to shorten the grinding time and increase mass productivity.

In addition, high-pressure denaturation and homogeneity are the most important points when making a blade. If there is variation in high density, the straightness of the cutting edge cannot be achieved, resulting in waves and poor cutting quality. In addition, economic efficiency and mass production are important points for industrial products.

When we consider the manufacturing method of razor blanks, taking into account these factors, we find that one of the most popular sheet manufacturing methods is slip-casting (slip molding).
Ca5t) and consolidation molding (Co15ol 1dati)
onCast) is considered to be the most suitable, but a comparison of these and other methods is as shown in Table 2 below.

2. High density and homogeneity are achieved in surface casting, while homogeneity is inferior in consolidation, but the productivity is noteworthy. On the other hand, with the hydrostatic pressure method or the pot press method, there is no problem in terms of quality, but the economical efficiency (productivity) is inferior. Due to these circumstances, razor blades made of zirconium were not commercialized.

First, one of the inventors of the present invention invented a fluid EE dense molding method as a method for molding ceramics, which is excellent in moldability, shape retention for demolding, high density, uniformity, and economical efficiency. The patent application was filed as ``Japanese Patent Application No. 136,845/1983, Fluid Consolidation Molding Method,'' and the inventors researched the application of this molding method to the molding of zirconia ring razor blades, and found that a clear razor material could be produced. They found that it can be obtained and completed the present invention.

In the fluid compression molding method, the zirconia powder/liquid bonding material is first shaped into a razor blade under a flow-excited state that allows it to exhibit its liquid properties, and then the shaped body is molded into a state in which it cannot flow. It is characterized in that it is placed under a condition in which it can exhibit its solid properties by being confined, and then it is compressed again to retain its shape and to make it possible to remove it from the mold. In other words, using the same molding material as raw material, the material put into the mold is first compressed from above at a high compression speed to make the material flow and form a convex shape, and the excess material is removed between the mold and the compressible material. It is extruded through the gap and discharged outside the mold.
Next, the gap between the compressibility and the mold is closed, and the compressibility is pushed down at a slow speed so that the shaped body cannot flow, solidifying it and maintaining its shape. The compressible pressing speed is determined to be an appropriate value for shaping and consolidation, respectively, based on the rheological properties of the material mud, and the pressure is applied at this value.

Since the molded body has sufficient shape retention properties, it can be demolded, and the thus obtained silica base is fired to obtain a razor material. Using a diamond abrasive,
The blade is sharpened to create a single-sided or double-sided polished blade.

Next, a coating is applied to the cutting edge or the vicinity of the cutting edge, or both of the blades, to form a product.

The coating may be, for example, a fluororesin coating.

For this coating, a mixture of oil-in-water emulsions of polytetrafluoroethylene and hydrogen methylpolysiloxane disclosed in JP-A-58-37094 entitled "Composition for coating cutlery" is preferably used.

According to the present invention, zirconia razor blades that are sharp, do not rust, and have a thin blade can be mass-produced, resulting in economic efficiency (
This makes it possible to provide high quality razor blades.

The present invention will be further explained below with reference to Examples.

Example 100 moles of finely powdered zirconia (Zr○2 purity 9'LOO%) (33 moles of Otsu NO were mixed therein, and 01% CMC was added thereto.

0.1% PVA, 0.2% PVA liquid emulsion (trade name: Maxelon), and 2 to 3% water were added and thoroughly mixed to obtain a molding raw material.

This was put into the mold shown in Fig. 1, and pressed from above by the compression column 3 at a compression speed set in advance to keep the molding raw material 1 in a fluid state, thereby shaping it into a thin plate. . Excess mud is discharged from the gap between the mold 2 and the compression column 3. Next, the gap between the mold and the punch was closed, and the punch was pressed at a compression speed set in advance so that the shaped body was in a solid state, thereby compacting it. Note that the operation was set so that the final molded body had a thickness of 0.5 mm, and the above-mentioned operation was performed under vacuum in order to prevent degassing and intrusion of outside air.

Demolding was carried out without any problems, and the sheet material after demolding was 1600 yen.
A razor material was obtained by firing at 6C for 2 hours.

This 05 mm thin plate was sharpened by the following polishing process.

1. Diamond whetstone $ 180 2 Same abrasive grain #500 3 Same abrasive grain + 3000 4. Diamond paste 0.5μ The razor sharpness obtained by this polishing process was determined by seven rules. As shown in Fig. 2, the measuring equipment consists of a nylon thread 5 stretched between pulleys 4 set at 20 cm intervals, and 10 nylon threads placed at each end of the thread.
A weight 6 of 0 gr is attached, a razor blade 7 is lowered at a constant speed by a motor, and the cut position of the system is indicated as a distance of 1 mm from the system level line. This distance is measure 8
It is read in. The measurement was performed on 10 blades and the average value was calculated. For comparison, measurements were also performed on zirconia molded by the casting method, fired and sharpened in the same manner as in the example, and on a commercially available stainless steel razor blade. The results are shown in Table 3.

Table 3 Judging from the results, the zirconia razor blades made by fluid compression molding have values equivalent to commercially available stainless steel blades, and the razor blades made by casting molding show considerably inferior cutting values.

[Brief explanation of the drawing]

Figure 1 is a new view of the equipment used for fluid consolidation molding;
The figure is a drawing showing a schematic structure of a razor blade sharpness measuring device. 1... Molding raw material, 2... Molding mold. 3... Compression column, 4... Pulley. 5. Mountain nylon type, 6.. Weight. 7...Razor blade. Patent Applicant Kundo Gonya Shiseido Co., Ltd. Agent Patent Attorney Keiji Matsunaga Figure 1 Figure 2 @ Procedural Amendment October 19, 1980 Commissioner of the Patent Office Kazuo Wakasugi 1, Case Indication Date 58 Patent Application No. 166949 2 Name of the invention Razor's Blade 3 Relationship with the case of the person making the amendment Patent applicant's name Kaoru Sakiya Representative Yoshibei Yamamoto Agent ``F156mA9..3)3゜2-485
0 Address: 3-27-27-6 Matsubara, Setagaya-ku, Tokyo
There is no increase in the number of inventions due to the amendment. 7. "Detailed description of the invention" column of the specification subject to the amendment & Contents of the amendment 1. Specification 2. 11. "Stainless steel blade" ,” is corrected. 2 Correct ``the best,'' in the second line of page 3 to ``the best force S, J + ko↑0.'' 3. Add ``yttrium acid,'' between ``calcium oxide.'' 4, page 4, line 1: ``It makes things worse.'' Amend J to ``make things worse.''& Same page 4th line 5th to 6th item (Consolidation Ca5t) Correct J to r (Con5o Ida tion) & Specification N6 4th line Correct “fast compression speed” to “slow compression speed” 47, same page 6, line 8, "slow speed" is corrected to "even slower compression speed". 8, same page 6, line 12, "acts at speed." 9, same page 8, lines 16 to 17, "cutting measurement" is corrected to "tI!J sharpness measurement". 10, same page 9, Table 3 Zirconia blade (cast-in) Cutting value column for molding) rlZIJ't
Corrected to rlZloJ. that's all)"

Claims (1)

[Scope of Claims] 1. A molding material containing zirconia as a main component is once placed in a fluidized state to be shaped into a razor blade station under conditions that allow it to exhibit liquid properties, and then the shaped body is fluidized. Razor blades are made by placing them under conditions that allow them to exhibit their solid properties by confining them under conditions that do not allow them to move, retaining their shape by consolidating them again, and then removing the mold, firing them, and attaching them to the edge. 2. The razor blade according to claim 1, wherein the cutting edge is a single-sided polished blade or a double-sided polished blade. & A razor blade according to claim 2, which has a coating on and/or near the cutting edge.