JPS60185710A - Bath preparation of weak acidity - Google Patents

Abstract

PURPOSE:A bath preparation of weak acidity containing carbonate salts and acid in which a specific dicarboxylic acid or its salt is used as the acid and the pH of the bath is adjusted to a specific value, when the preparation is dissolved, to prevent the boiler and the bathtub from being corroded. CONSTITUTION:The objective bath preparation of weak acidity contains at least one of carbonates such as sodium bicarbonate, sodium carbonate or sodium sesquicarbonate and at least one of an organic acid of the formula: (CH2)n (COOH)2 (n is integer of 0-6 other than 2) or its salt and shows a pH of 4-7 (as 0.01wt% concentration solution), when it dissolved in the bath. Since it is weak acidic before bathing, it does not hurt the boiler and bathtub and gives good effect on the skin, during bathing, because the pH is almost the same with that of human skins, further carbon dioxide molecules evolving during bathing accelerate the blood circulation in skins.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel weakly acidic bath additive, and more particularly to a weakly acidic bath additive containing a carbonate and a specific acid that causes less damage to bathtubs and bathtubs.

Bath additives are generally a mixture of inorganic salts such as mirabilite, borax, sulfur, salt, carbonate, etc., combined with fragrances, colorants, plant extracts, organic acids, etc. By providing moderate stimulation to the skin, it activates blood circulation, relieves fatigue, and improves metabolism. Among these bath additives, there are effervescent bath additives that combine carbonate and acid, which generate carbon dioxide gas bubbles in the bath water.
It has the effect of increasing the feeling of relaxation and refreshment and making bathing more enjoyable.

When a bath agent containing the above carbonate and organic acid is added to bath water,
The two react to generate carbon dioxide gas, but the effect of the carbon dioxide gas varies depending on the pH of the bath water. In other words, when the pH is acidic, carbon dioxide gas exists as CO molecules and exhibits a blood flow promoting effect, but when the pH is alkaline, carbon dioxide gas exists as CO3 ions or HCO3- ions, so this effect is not observed at all. I can't do it. Therefore, in order for the effervescent bath agent to be effective, it is necessary to use it in such a way that the pH of the bath water becomes slightly acidic when it is added.

However, the bath additives commonly used in households are neutral or weakly alkaline, mainly containing inorganic salts such as mirabilite, sodium bicarbonate, and sodium carbonate; It was said that it would damage bathtubs and bathtubs, making it difficult to put it into practical use.

Therefore, the inventor of the present invention conducted intensive research in order to develop a bathing agent that does not have the above-mentioned drawbacks, considering that the pH of human skin is weakly acidic, and that weakly acidic bathing agents have a favorable effect on the skin. As a result, there were concerns that using acids represented by (CH) (COOH)2 or their salts to make weakly acidic bath additives instead of the commonly used acids citric acid and tartaric acid. The present invention was completed after discovering that there is almost no corrosion in bathtubs and bathtubs.

That is, the present invention provides a bath additive containing a carbonate and an acid, in which (CH,
] Contains one or more selected from the group consisting of organic acids and salts thereof, and has a pH of 4 to 7 (0.01% by weight) when dissolved in bath water. % aqueous solution)
The present invention provides a weakly acidic bath additive having the following properties.

Examples of the carbonate used in the bath additive of the present invention include sodium bicarbonate, sodium carbonate, sodium sesquicarbonate, and the like, and these can be used alone or in combination of two or more.

In addition, examples of organic acids include glutaric acid, malonic acid,
Examples include acids such as azopic acid, pimelic acid, and oxalic acid, and alkali metal salts such as sodium hydrogen glutarate and sodium hydrogen malonate, and these are selected and used depending on the various effects of the bath additive. When n=7 (azelaic acid) or more, water solubility is poor and the effects of the present invention are not achieved.

The blending amount of acid and carbonate is such that when the bath additive is added to the bath water, the bath water becomes weakly acidic.
It is necessary that the 1% by weight aqueous solution has a pH of 4 to 7.

If the pH is lower than 4, it is not preferable because it is highly irritating to the skin and may damage the bathtub. For this purpose,
For example, when azopic acid is used as the organic acid, it is preferable that the blending amount is 20 to 150% by weight (hereinafter expressed as %) based on the carbonate (in terms of sodium bicarbonate).

In addition to the above-mentioned essential components, the bath additive of the present invention may contain sulfates such as sodium sulfate, magnesium sulfate, zinc sulfate, etc., or hydrochlorides such as sodium chloride. The blending amount of these is preferably 30 to 500%, particularly 50 to 300%, based on the amount of acid.

Furthermore, the bath additives of the present invention may contain fragrances, pigments, or vitamins, active ingredients of hot springs, proteolytic enzymes, seaweed extracts, sodium alginate, lanolin, silicone, amphoteric surfactants, herbal medicines, or herbal medicines. The effect can be further enhanced by adding extracts and the like.

The bath additives of the present invention can be in the form of powders, granules, crystals, tablets, etc., and excipients, binders, disintegrants, lubricants, etc. may be added as necessary to form these formulations. It can also be added. As for the dosage form, tablets are preferred from the viewpoint of efficiency in dissolving carbon dioxide gas.

Although the bath additives of the present invention, such as Slanted, are weakly acidic, they do not damage bathtubs and bathtubs, and have a positive effect on the skin because their pH is approximately the same as that of human skin. Moreover, the carbon dioxide gas generated when pouring into the bath water exists as ions in alkaline conditions and has no blood flow promoting effect, but in acidic conditions as in the present invention, it exists as CO, molecules and has an excellent effect of promoting blood circulation in the skin. be effective.

Next, an example will be given and explained.

Example 1 A bath additive having the composition shown in Table 1 was prepared, and its influence on a steel bath pot and an enamel bathtub was investigated.

The results are shown in Table 2.

(1) Effects on copper bath pots ■ Elution of Cu from copper powder 100g of copper powder for each 0.2% water-soluble 125td bath salt!
q was added, and the mixture was treated in a hot bath at about 80° C. for a day and night, and the Cm eluted into the solution was quantified by atomic absorption t.

Q) Elution of Cu from copper bath pot Bathtub V of copper bath pot (manufactured by Kongo Renki Seisakusho) 0 of individual bath additives
Add 180t of 2% aqueous solution and heat until it reaches 60℃.
-Leave it alone day and night.

The same operation was performed on the second day, and Cu was quantified in the bath water on the third day (48 days).

(2) Effects on enamel bathtubs Teston Luster (closed, Q-Tsuchi test bandage) is impregnated with 0.2% aqueous solution of each bath additive, and pasted on an enamel test piece (obtained from Japan Enamel Industry Association). It was left at room temperature.

After 48 hours, the test plaster was peeled off, and the effect on the enamel surface was evaluated using the following items and scores.

■ Change in gloss ○: No change Δ: Slight change ×: Change ■ ○: No change △: Slight change ×: Change υ Margin table below-2 Example 2 Bath additives with the composition shown in Table-3 were prepared. It was used for 3 months in the same way as regular bath additives (approximately 0.01% added to bath water). As a result, there was no damage or discoloration in the bathtub or bathtub.

Claims (1)

[Claims] 1. In a bath additive containing carbonate and acid, as acid (COOH). [wherein n is an integer of 0 to 6 (fc, excluding n=2)] The bath additive contains one or more selected from the group consisting of organic acids and their salts represented by: Pi is 4 to 7 when dissolved in bath water (0.01% by weight aqueous solution)
A weakly acidic bath additive.