JP3293648B2 - Black key of keyboard instrument and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a black key for a keyboard instrument and a method for producing the same. And the coloration of the coloring is suppressed over time.

[0002]

2. Description of the Related Art Conventionally, in a keyboard instrument such as a piano, the material of a black key is a tactile sensation such as a moderate frictional resistance, a surface hardness,
Ebony has been considered suitable for its appearance and other colors.

However, due to recent wood circumstances, there are problems such as color unevenness peculiar to natural materials and color variation among individuals. For example, ebony is not all black. Therefore, ebony is used on the premise that it is colored.

For this coloring, a method has been adopted in which ebony is immersed in a dye and a solvent to impregnate the inside of the ebony with the dye. When ethyl acetate or the like having excellent permeability is used as the solvent, the inside of the wood is stably colored, but there is a drawback that the color fades due to the action of sweat or the like over a long period of time.

On the other hand, when a phenolic resin or the like is used as the impregnating liquid, there is no discoloration, but the permeability is poor, and it is necessary to repaint after immersion. As a result, the surface characteristics of the ebony were impaired, and the playability and appearance were poor.

As described above, the conventional ebony coloring technique cannot achieve both of the characteristics of the black key surface, for example, the excellent tactile sensation of the ebony and the change over time of the color.

Japanese Utility Model Laid-Open Publication No. Sho 59-51394 proposes a technique for streamlining the work of applying black paint by fitting a black key cap for covering the side surface to the tip of the black key body. I have. However, this also impaired the surface feel of the ebony and was not sufficient as a black key for keyboard instruments.

Accordingly, an object of the present invention is to provide a black key of a keyboard instrument capable of maintaining the tactile sensation as wood and suppressing the secular change of coloring, and a method of manufacturing the same.

[0009]

The invention according to claim 1 is
In a black wood key, at least a predetermined depth of the impregnating liquid comprising a black colorant and a synthetic resin liquid is injected under reduced pressure from a contact surface of the player to a predetermined depth, and the black key of a keyboard instrument having a resin-processed resin part heated and polymerized. It is.

The invention according to claim 2 is a process for preparing an impregnating liquid by preparing a black colorant and a synthetic resin liquid, injecting the impregnating liquid at least from the surface of wood under reduced pressure, And heat-polymerizing the impregnating liquid injected into the instrument.

[0011]

According to the first aspect of the present invention, since the black key is made of wood, the tactile sensation (friction resistance) when pressed during the performance does not cause any discomfort as compared with the ebony keyboard. In addition, since the synthetic resin to which the black colorant is added over a predetermined depth from the player's contact surface is injected at least under reduced pressure and then heat-polymerized, the colored resin is stable in a state chemically bonded to the wood. Therefore, discoloration and uneven color due to long-term use can be prevented.

According to the method of manufacturing a black key for a keyboard instrument according to the second aspect, an impregnated resin solution is injected into wood at least under reduced pressure, and then heated to polymerize the impregnated resin.
As a result, the resin is chemically bonded to the wood in the wood-made black key. Then, the colorant contained in the impregnated resin liquid is present in the black key in a stable state together with this resin. Wood is colored evenly and stably.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the method for producing a black key of a keyboard instrument according to the present invention will be described below.

First, hardwood such as striped ebony, beech, hard maple, maple, hippopotamus, wig, or softwood such as agatis is prepared as wood. These woods are not necessarily black in appearance. These woods are dried so that the water content thereof is 10% or less, preferably 8% or less.

After the drying, the wood is treated with W
PC (Wood Plastic Composite)
Processing is performed. That is, the above-mentioned wood is impregnated by injecting a resin solution under reduced pressure or, if necessary, further under pressure, and is heated to polymerize the resin by heating.

In this case, as the resin solution to be impregnated, in the case of an oil-soluble system, for example, a vinyl-based monomer such as methyl methacrylate (MMA), vinyl acetate, unsaturated polyester, or the like may be used alone or as a mixture. A polymerization initiator such as benzoyl peroxide is dissolved in this resin liquid. Or,
An ionic polymer resin such as an epoxy resin or a urethane resin may be used. In the case of these resins, amines, acid anhydrides, etc. are used as curing agents in the former, and TDI is used in the latter.
(Tylenediisocyanate), MDI
(Methylendiisocyanate) or the like is used. In the aqueous system, a cocondensate of melamine or phenol and formaldehyde is used.

Further, a black colorant is previously prepared and added to these resin liquids to prepare a liquid impregnating liquid. Examples of the black colorant include acid dyes such as acid azo dyes, metal complex salt azo dyes, oxidation dyes of aromatic amines,
Pigments and the like are suitable. However, carbon black is not suitable for vinyl monomer resin liquid. This is because it inhibits radical polymerization.

Then, the impregnating liquid prepared as described above is injected into the dried wood as described above under a predetermined reduced pressure condition (for example, 0.5 to 2 hours at 1 to 20 [mmHg]). After the injection, the wood is pressurized under predetermined conditions (1 to 50 [Kg / cm ² ] for 0.5 to 20 hours).

Further, after the impregnating solution is injected, the vinyl monomer resin is heated at 50 to 80 ° C. to polymerize.
Insoluble and infusible. In the case of a melamine or phenolic resin, the polymer is heated to 120 to 150 [° C.] and polymerized.
Insoluble and infusible. When an epoxy resin or a urethane resin is used as the ionic polymerized resin, the resin is heated to 50 ° C. to 150 ° C. for polymerization. As a result, a resin processing portion is formed over a predetermined depth from the surface of the wood constituting the black key. The black key is colored black. And this wood is formed as a black key.

Therefore, according to the above-described embodiment, even if wood harder than ebony is not used, by performing the above-mentioned treatment on softer wood, it is possible to obtain a necessary and sufficient weight and surface hardness as a black key. it can. That is,
By performing the above treatment on soft wood, the durability against flaws and the like is improved. These characteristics can be adjusted by controlling the impregnation amount according to the type of the resin and the impregnation conditions, and can be freely adjusted particularly in the case of soft wood capable of obtaining a high impregnation amount. . In this case, the soft wood does not mean softwood which is softwood, but has a low wood density,
For example, it includes conifers or hardwoods in the range of about 0.3 to 0.5 [g / cm ₃ ]. By the way, hard wood has high density, for example, about 0.7 to 0.9.
[G / cm ₃ ] or a range close to 1.0 [g / cm ₃ ].

[0021]

As described above, according to the present invention, the resin to which the black colorant is added is injected at least under reduced pressure into the interior of the wood and then heat-polymerized, so that the colored resin is chemically bonded to the wood. It exists in a stable form. As a result, a temporal change of the color of the black key, for example, color fading, fading, and the like are suppressed.

Also, unlike the case of the conventional surface coating,
It has excellent playability without significantly changing the tactile sensation of the surface of wood such as ebony, that is, frictional resistance.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-110894 (JP, A) JP-A-48-104519 (JP, A) JP-A-1-253401 (JP, A) 12189 (JP, U) JP-A 54-45527 (JP, U) JP 3-33493 (JP, B2) JP 31-912 (JP, B1) (58) Fields surveyed (Int. ⁷ , DB name) G10C 3/12 B27K 3/15

Claims (2)

(57) [Claims] 1. A wood key made of wood, which has a resin-treated portion in which an impregnating liquid composed of a black colorant and a synthetic resin liquid is injected at a reduced pressure at least over a predetermined depth from a contact surface of a player and heated and polymerized. A black key for a keyboard instrument. 2. A step of preparing a black colorant and a synthetic resin liquid to prepare an impregnating liquid, a step of injecting the impregnating liquid at least from the surface of wood under reduced pressure, and heating the impregnating liquid injected into the wood. A method for producing a black key for a keyboard instrument, comprising: a superposing step.