JPS5811215B2 - Transparent gel composition for bioelectrode - Google Patents

Description

Detailed Description of the Invention The present invention aims to reduce the contact resistance between the electrode and the skin surface when extracting electromotive force from the living body or applying electricity to the living body. The present invention relates to a transparent gel-like bioelectrode composition that is interposed in a bioelectrode.

Conventional bioelectrode compositions have the disadvantage that if they are in contact with the skin for a long time, they flow depending on the skin temperature and have a high drying resistance.

In addition, the composition causes a salting-out phenomenon due to sweating during use,
It is also well known that changing from a gel-like or paste-like state to a liquid state reduces the adhesion between the electrode and the skin and increases the contact resistance.

On the other hand, a low-frequency treatment device (pine surge device) is effective for treating neuralgia and muscle pain, as well as for recovering from fatigue, by applying pulsed current to two parts of the body via conductors to cause contraction movements in the muscles. Similarly, the adhesion between the electrode plate of the conductor and the body is decreased, contact resistance is increased, and the skin is likely to be irritated.

The present invention has improved all of the above-mentioned drawbacks.The purpose of the present invention is to maintain proper contact between the skin and the electrode, reduce contact resistance, ensure good conduction at low frequencies, and be stable against body temperature and perspiration. To provide a transparent gel-like bioelectrode composition that does not flow or denature, retains an appropriate amount of moisture from beginning to end, gives a moist and good feel, and has good wipeability and storage stability. There is a particular thing.

That is, the present invention is a transparent gel-like bioelectrode composition containing carboxyvinyl polymer, potassium phosphate, disodium phosphate, propylene glycol, and water as main components.

The amount of carboxyvinyl polymer used in the present invention is 0.3 to 5 parts by weight, preferably 1 to 4 parts by weight.

When the weight ratio is less than 0.3, it becomes a liquid even at relatively low temperatures (does not form the desired gel-like material), and may flow and be interposed between the skin and the electrode. It can also be difficult to maintain proper contact.

If the weight exceeds 5, the viscosity becomes high, which tends to cause air to get mixed in and thereby increase the contact resistance between the skin and the electrode, and cause pain to the skin when it comes into contact with the conductor of the low frequency treatment device. It becomes easier.

Potassium phosphate and disodium phosphate are 1:5 to 10,
Preferably, the ratio of 1:7 to 9 and the total amount of both is 0.5 to 11% by weight based on the total amount of the composition.

If the amount is less than the above minimum limit, the pH buffering effect and viscosity will decrease, and the storage stability of the composition will tend to deteriorate.

Furthermore, if the amount exceeds the maximum limit, salting-out limitations occur, resulting in opacity, water separation, and poor storage stability.

The amount of propylene glycol blended is 5 to 45% by weight, preferably 14 to 30% by weight based on the total amount of the composition.

When the amount is less than 5% by weight, the composition tends to dry out and increase contact resistance, resulting in decreased adhesion and opacity, and also imparts a moist and good feeling to the skin (moisture feeling, etc.). hard.

When the amount exceeds 45% by weight, storage stability tends to deteriorate.

The amount of water blended is 38 to 93% by weight based on the total amount of the composition,
Preferably it is 52 to 82% by weight.

When the amount is less than 38% by weight, the composition tends to become unstable in the summer, and when it is more than 93% by weight, the composition tends to become unstable in the winter.

Components that can be appropriately added to the composition of the present invention as needed include fragrances, coloring agents, neutralizing agents, skin nutrients, sodium chloride, and the like.

The transparent gel-like bioelectrode composition of the present invention is prepared by dispersing carboxyvinyl polymer in fluoropylene gellicol (if necessary, adjusting the composition to pH 6 with an alkaline aqueous solution).
After neutralizing to about 2 to 7.0), an aqueous solution of potassium phosphate and disodium phosphate is added thereto with stirring,
Manufactured by mixing.

The composition for a bioelectrode of the present invention forms a transparent and beautiful gel (jelly-like transparent cream) that is colorless or colored in a desired hue, and has temperature stability, storage stability (oral stability ), and during use, it maintains appropriate moisture in itself and the skin, giving a moist and good feeling (moisture feeling), while properly adhering the electrode (or conductor) to the skin, It reduces contact resistance and improves low-frequency conduction, and its action and effect are extremely specific. It is extremely useful as a bioelectrode composition (paste or cream).

The present invention will be explained in detail below.

In the examples, parts mean parts by weight, and % means weight %.

In addition, the storage stability, viscosity and practical tests, contact resistance, drying resistance (water retention), salting-out resistance (salting-out resistance), and adhesion (degree) of the compositions shown in the examples were determined as follows. Examined.

(1) Storage stability If a sample is stored in a constant temperature room for 6 months with a cycle of 2 weeks at -10°C and 2 weeks at 45°C, and the appearance is transparent and no water comes out, it is stable and opaque. If it ejects, it is classified as unstable.

(2) Viscosity Using a Brookfield rotational viscometer (Type B), 30
Expressed as centipoise (cps) values measured in °C.

(3) Practical test A panel of 30 men and women were used to investigate the use of the product as a cream for the conductor of a low-frequency therapy device, and the number of people who answered that it was good and whether or not they perceived it to be painful were also shown.

(4) Contact resistance The contact resistance was measured using electrodes (diameter 10 m) impregnated with the composition on both arms.
The resistance at both ends of the electrode was measured with a vacuum tube ammeter every 10 minutes for 1 hour, and the value was Ω.

(5) Drying Resistance (Water Retention) A small amount of each composition was placed on a glass plate, and the composition was tilted at a 30° angle in a constant temperature bath at a temperature of 50° C. The quality of each composition was determined by scoring the changes in each composition.

The higher the number of points, the more drought resistant it is.

2 grams of each composition, which has a score of 0 to 10, was placed on a glass plate, 0.5 cc of 5% sodium chloride was injected, and the composition was tilted at an angle of 30° to observe changes in each composition at 18 to 20°C. Goodness is determined by score.

The higher the score, the better the salting-out resistance.

Scores range from 0 to 10. (7) Adhesiveness (degree of adhesion) Using double-sided adhesive tape, put each composition on the electrode and attach it to the living body on glass.
It was allowed to stand at room temperature between .degree. C. and 20.degree.

The degree of adhesion of each composition is expressed by a score of 0 to 10, and the higher the score, the better the degree of adhesion.

Example 1 (1) A transparent gel composition for a bioelectrode of the present invention.

Carboxyvinyl polymer (Carphohol 940')
1 part propylene glycol 25 disodium phosphate 2°5 potassium phosphate
0.5 sodium hydroxide
0.26 dye
Appropriate amount of methyl parabenzoate 0.1
Add 0.1 parts of water to bring the total amount to 100 parts.

Mix and stir Carbopol 940 uniformly with propylene glycol and knead well.

Next, add IJum to a portion of the water and stir into a homogeneous solution to create (A).

Disodium phosphate, potassium phosphate, dye, and preservative are uniformly dissolved in the remaining water to prepare (B).

Next, (B) was uniformly added to the above (A), and then a fragrance was uniformly added to obtain a transparent gel-like bioelectrode composition.

Comparative Examples 1 to 4 ■ Comparative Example 1 was carried out in the same manner as in the present invention except that polyvinyl alcohol was used instead of Carbopol 940.

However, sodium hydroxide is not used.

(2) Comparative Example 2 was carried out in the same manner as in the present invention except that Carbopol 940 and sodium hydroxide were not used.

(2) Comparative Example 3 was carried out in the same manner as in the present invention except that propylene glycol was not used.

○ As Comparative Example 4, the same procedure as in the present invention was carried out except that disodium phosphate and potassium phosphate were not used.

As is clear from these results, the transparent gel-like bioelectrode composition of the present invention has better transparency, storage stability, viscous drying resistance, salting-out resistance, and practical test results compared to the composition of the comparative example. is significantly superior.

Even if analogous components are used in place of the constituent components of the present invention, the desired transparent gel-like bioelectrode composition cannot be obtained.

Example 2 The same procedure as in Example 1 of the present invention was carried out except that the content of carboxyvinyl polymer (Carbopol 940) was changed as shown in Table 2.

The results are shown in Table 2.

As is clear from this result, the content of carboxyvinyl polymer (Carbopol 940) is 0.3 to 5%, preferably 1 to 4%.

Example 3 1. Phosphate (potassium phosphate and disodium phosphate)
The same procedure as in Example 1 of the present invention was carried out except that the content of was changed as shown in Table 3.

The results are shown in Table 3.

As is clear from this result, the phosphate content is 0.5
-11%, preferably 2-7%.

Example 4 The same procedure as in Example 1 of the present invention was carried out except that the content of propylene glycol was changed as shown in Table 4.

The results are shown in Table 4.

Claims (1)

[Scope of Claims] 1. A transparent gel-like bioelectrode composition comprising carboxyvinyl polymer, potassium phosphate, disodium phosphate, propylene glycol, and water as main components. 2. The bioelectrode composition according to claim 1, wherein the carboxyvinyl polymer is blended in an amount of 0.3 to 5% by weight based on the total amount of the composition. 3 Potassium phosphate and disodium phosphate in a ratio of 1:5 to 1
2. The bioelectrode composition according to claim 1, wherein the bioelectrode composition is blended in a ratio of 0.0 to 11% by weight based on the total amount of the composition. 4 Propylene glycol is 5 to 5% of the total amount of the composition.
The bioelectrode composition according to claim 1, which is formulated in a weight ratio of 45% by weight. 5. The bioelectrode composition according to claim 1, wherein water is added in a proportion of 38 to 93% by weight based on the total amount of the composition.