JPS58106597A - Chord surface treatment for musical instrument - 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 a surface treatment method for musical instrument strings to prevent rust and discoloration, and in particular, the formation of a thin film of plasma 1 as a protective film essentially impairs all sounding characteristics. The aim is to provide anti-corrosion and anti-discoloration effects without any damage.

The metal strings used as the sounding bodies of various instruments are susceptible to rust or discoloration for various reasons. For example, something like a guitar that you can touch directly with your hands other than just to pronounce it,
It is particularly susceptible to rust due to human sweat containing salt, etc. Even for items that do not come in direct contact with the human body, such as the strings of a straddle string, changes in indoor humidity and temperature can cause hooks to form due to condensation, or even discoloration even if the string does not rust. However, such rusting or discoloration can significantly reduce the commercial value of not only the strings but also the instrument that contains them, if they are not yet sold, and if the strings are in use, the discoloration is only noticeable, but Rust can cause changes in tone and disconnection during performance.

In order to prevent metal strings from rusting or discoloring as described above, conventionally, a protective film has been formed by applying liquid synthetic resin, plating with corrosion-resistant metal, applying anti-caking oil, etc. There is. All of these methods are effective in their own way in terms of simply preventing rust or discoloration.

However, each of these methods has the following points. That is, in the method of forming a resin coating film, pinholes generally occur in the coating film due to evaporation of the solvent during drying, and the desired effect cannot be obtained unless the coating film is thick. However, such coatings generally have the effect of damping the vibrations of the strings, and the thicker the coating, the worse the damping effect (reducing sound quality). It is generally difficult to form a complete film, and simple spray application is not suitable, and W is usually added to the paint dilution solution.
The method of drying is adopted, but the loss of bath additive during drying is large. Moreover, the working environment becomes very bad.

On the other hand, the plating method is also very difficult to process, and although the film may be relatively thick, the specific gravity is low, so the sound quality may similarly deteriorate as the load increases.

Furthermore, methods of applying oil by brushing or the like have poor sustainability of the effect, and when applied to the winding shaft, the oil becomes sticky and difficult to remove. In the case of pianos in particular, oil can seep into the hammer felt that hits the strings, causing deterioration of the quality of the felt and causing a change in tone.

There is also a method of modifying the string material itself so that it does not corrode or discolor by using an alkali conversion method, but such material modification tends to lead to deterioration of sound quality.

In view of the above-mentioned circumstances, it is an object of the present invention to provide a method for treating the surface of musical instrument strings to prevent rust and discoloration, which may cause essential deterioration of sound quality.

According to the research conducted by the present inventors, it has been found that forming a polymer core on a musical instrument string by a plasma polymerization method is extremely effective for achieving the above-mentioned object. That is, according to Plasma Togane, it is possible to form a homogeneous ultra-thin film relatively easily even on a thin and long string. The mechanism of adhesion of the formed polymer film is not necessarily clearly elucidated, but it is assumed that the monomer is ionically attached to the base metal. Because of this, it adheres closely to the base metal, and can be formed as a high-quality ultra-thin film (about 0.2 to 2 μm) in a commercially available manner. Therefore, the necessary anti-corrosion and anti-discoloration effects can be provided to the metal strings even when the thickness of the metal string 11 is so thin that it does not cause a substantial deterioration in sound quality.

(3) In general, a polymer film with a higher degree of crosslinking can be obtained compared to polymers obtained from the same monomer by other commonly used polymerization methods, and this also points out that the Wi film retains the time of the Kinshingen base material. advantageous for. In addition, unlike the formation of a polymer film by ordinary painting, the work is carried out in a closed container, so there is no deterioration of the work environment (in addition, the plasma polymerization time and voltage are completely controlled, so the film properties It is also easy to control the film thickness.

The surface treatment method for a certain instrument string of the present invention is based on the above-mentioned findings, and is characterized by forming a protective film on the surface of the metal string by plasma polymerization.

This invention will be explained in more detail below.

The metal string base material used in this invention can itself be used as a metal string for a musical instrument. Winding wires or trowel-plated wires can also be used.

(4) As a plasma polymerization device, a generally known device can be used.
The one shown below is used. i.e. Pelger 1
Diffusion pumps 2a, 2b and a rotary pump 3a are installed as pressure reducing devices in the reactor consisting of a or tube 1b.
, ab f, and from the monomer sources 4a, 4b as well as stop valves 5a, 5b and 21 dollar parzo 6a.
, 6b f into the monomer supply piping 7a, 7b'. In addition, Isuna's equipment also uses two monomer supply sources.
By providing sleeves, it is possible to achieve both 1° alignment. Reactor 1a
, Ib has historical sources 4c, 4d, J Luso 5c, 5
Inert gas such as N2 and Ar is introduced through d, 6c, and 6di. In addition, both devices have, for example, 13.5
6 MI-(Z) is equipped with a high-frequency excitation power source 8a at Bidai University, and in the apparatus shown in FIG.
a is provided. Further, in the apparatus shown in FIG. 1(b), a coil 10 is first suspended from a metal string in the reactor 1a, Ib at the plasma gas introduction part.

Next, reactor 1a, 1. I Torr ~10-
' Pressure is increased to about 7 Torr. At this time, it is preferable to clean the inside of the system and the string base material by plasma etching using an inert gas such as N2 or argon.

Next, the monomer is introduced into the system from the supply m4a or 4b, and the monomer is excited and turned into plasma by the high frequency field applied from the high frequency power sources 8a and 8b. At this time, in the apparatus shown in Figure 1 fb), inert gas such as Ar, N2, etc. from the supply source 4d is turned into plasma, and this is mixed with monomer to indirectly form monomer plasma. The monomer plasma thus formed contacts the surface of the string and forms a polymer film there. As another method, it is also possible to continuously process long wire materials using the apparatus shown in FIGS. 1fc) and 1(d).

At this time, the total thickness of the polymer film formed on the string can also be controlled by placing a flat plate in parallel with the string and precisely measuring the increase in amount due to the polymer film formed thereon.

As monomers, in addition to olefinically unsaturated compounds that are not used in normal radical polymerization, saturated hydrocarbons such as methane and ethane, or monomers (good compounds, NH3, SO
2. HCI, co, CO2, gas, or mixtures thereof, etc.') Organometallic compounds such as turnip compounds, tetramethylsilane, tetramethyltin, tetramethylgermanium, etc., as long as they can be gasified, can be used for polymerization. Most compounds can be used, although there are differences in difficulty. More specifically, the monomers used in this invention include saturated or un*p-phase complex hydrocarbons such as methane, ethane, ethylene, acetylene, and propylene; toluene, xylene,
Aromatic compounds such as styrene, chlorobenzene, pyridine, divinylpenzene, nitrogen-containing compounds such as acrylonitrile, propionitrile, 7-enylamine, ammonia, tetramethylsilane, ethylenesiloxane, hexamethylsiloxane, trichloromethylsilane, tetraalkyl Silicon-containing compounds such as silicone; other methyl chloride, tetrafluoroethylene, methyl alcohol,
Ethyl alcohol (7) coal, titanium tetrafluoride, air, natural gas, titanium tetrachloride, titanium dichloride, tetraethyltin, tetraethylgermanium, and the like can also be used.

Among the above-mentioned monomers, aromatic, nitrogen-containing (>Nl(
, -NH2, -CN), silicon-containing, olefinically unsaturated compounds, etc. are particularly preferably used because they are easy to combine and provide a dense and strong coating over the entire thickness.

In general, in order to obtain a polymer film with good properties, 1'r
At specific soft low pressure such as orr~1ff5Torr,
It is preferable to proceed with polymerization at a relatively high image output while flowing the monomer at a relatively high flow rate. However, since these conditions act in a way that vaguely lengthens the polymerization time, it is necessary to determine all the conditions in accordance with the compatibility of the monomers, taking economic considerations into account.

In the winding type device, the trough passes through the pole 1 once, and the film thickness etc. are the same in each part, but in the d conduction type device (d, the monomer density is made uniform # all monomers are introduced) It is necessary to devise methods such as adjusting the method.Generally, by heating the base material, a substance without hydrogenation such as C-C-C(8) or C-8i-C-8t- can be obtained. The properties of the polymer obtained by polymerization can be changed by incorporating elements other than the monomer. For example, if a monomer containing relatively corrosive elements such as fluoride or chlorine is used, the properties of the electrolyte material can be changed. Metals (such as Mg) may be taken in during coalescence, and N2 is also taken in when N is used as the plasma gas. When taken out, the remaining radicals react with oxygen in the air, and oxygen is taken in.

In this way, a plasma 1 coalesced film having a desired thickness is formed on the string base material. The film thickness is 0.2 to 2 μm, especially 0.
．． A range of 5 to 1 μm is preferred. If the film thickness is 0.2 μm or less, the effect of preventing rust and discoloration of metal cladding is poor, and if it exceeds 2.0 μm, the deterioration of sound quality due to loss of perturbation energy cannot be ignored.

As mentioned above, according to the present invention, the degree of crosslinking is generally higher than that obtained by conventional polymerization methods on metal string substrates (by forming dense plasma polymer detachments, it is possible to obtain Metal strings with low rust and discoloration are provided without deterioration in sound quality like polymerization that forms a coating film.Moreover, the polymer film is formed by plasma polymerization in a closed atmosphere. Since this process is carried out, it also has the advantage of being easy to work with and does not cause any deterioration of the environment.

Hereinafter, this invention will be explained in more detail with reference to all embodiments.

Polymers llφ were formed on various types of gold strings using a capacitive plasma single reactor as shown in Figure 1 (, ).

All 1 strings include @1.075 muφ carbon steel core wire, 1,001flthφ dipper, chiyu winding (for guitar), Ag plating Cu (for guitar), and Cu
Winding wire (for piano) 3 rod windings (length 1
5Q#llll1) was used.

First, lower the metal string door into the jar la, and place one each
After holding the apparatus so that the main body rotates around the string axis and the whole technique revolves, the gold thickness in the system is reduced and plasma sputtering is performed using Ar gas at 50rnA and 0.2 Torr. I did it. Next, use all of tetramethylsilane as a monomer at the following flow rates: 3.57 (STP)/min for guitar strings, 3.82 for guitar plated Cu-wound strings, and 3.82 for piano Cu-wound strings. In the case of a string, plasma polymerization during addition was performed under the conditions of a pressure of 0.2 Torr, an excitation power frequency of KHz, and an output cuff of 0 mA while flowing at 3.94 // to obtain a polymer film with a thickness of about 1 μn1. .

The strings obtained as described above were subjected to an artificial sweat test, a sulfurization test, a salt water @ fog test, and a moisture resistance test.1- As a result, corrosion resistance with no open circuits was obtained in all tests, and the sound quality was improved. No deterioration was observed.

On the other hand, the above metal shell was coated with 5μ
When the melamine resin coated metal was formed, the corrosion resistance was equivalent to that of the above-mentioned plasma polymer film, but deterioration in sound quality was observed.

[Brief explanation of drawings]

M1 diagrams (a) to d) are schematic diagrams each showing an example of a plasma polymerization reaction apparatus used in the present invention. 1a to 1d...Reactor, 2a, 2b...Diffusion pump, 3a, 3b...Rotary 7I sensor, 4a, 4b
... Monomer supply source, 4c, 4d... Plasma gas supply source, 5a-5d... Stop pulp, 6a-6d
... Rotary pulp, 7a, 7b... Monomer supply piping, 8a, 8b... High frequency' power supply, 9a, 9c,
9d...Internal counter electrode, 10...Ring conduction coil, ]1
...String base material, 12...Vacuum piping, 13...Electrode terminal, 14...Vacuum gauge piping. Applicant's agent Kiyoshi Inomata Procedural amendment filed in January 1980 Director General of the Japan Patent Office Shima 1) Haruki Tono1, Indication of the case 1982 Patent Application No. 2055012, Name of the invention Surface treatment of strings for musical instruments Law 3, Person making an amendment Related to the case Patent applicant (407) Nippon Gakki Mfg. Co., Ltd. 7, "Claims" and "Detailed Description of the Invention" columns 8 of the specification to be amended, Contents The specification of the present application is amended as follows. (1) Amend the claims as shown in the attached sheet. (2) The following sections have been amended as follows. 4 4 from the bottom 0.2 0.011 (
1140,20,01 10150,50,05 10150,20,01 Attachment [2, Claim 1, Surface treatment of musical instrument strings characterized by forming a protective film on a metal-clad surface by plasma polymerization method Law. 2. The method of item 1 above, in which the protective film is formed to a thickness of 0.01 to 2 μm. ” (1)

Claims (1)

[Claims] A method for surface treatment of strings for musical instruments, characterized in that a protective film is entirely formed on the surface of a 1° metal string by plasma polymerization. 2. The above-mentioned first step of forming the protective film to a thickness of 0.2 to 2 μm
Section method.