Abstract
It has been well recognized that no known method can produce as strong or as effective a bath as can be given with natural waters.
The method of bubbling gas through the bath water is thought to be almost entirely ineffective; the solubility of CO2-gas in water at 40°C is about 10%, but is much further enhanced about 50% by bubbling through an airstone, making fine bubbles.
Tablet form of the CO2-bath preparation, made from bicarbonate and succinic acid, produces fine CO2 bubbles so that about 80% of water solubility at 40°C can be obtained.
A CO2-bath preparation, 50g tablet, can produce 100ppm in maximum concentration in a bath of 150 liter at 40°C, maintaining the level of more than 60ppm for 2 hours.
In order for the safety to estimate the escaped CO2, a large quantity of the CO2-bath preparation, 20 and 50 tablets, was used in a relatively air tight room; CO2 concentration reached the maximum level of 1.9 and 6.6% respectively with a tendency of rapid falling, so that the critical complications could rarely be happened.
