About soap


About soap

Materials and ingredients, production methods and usage directions. Also introducing the characteristics of soap.

  • Q:What is a pot boiling method? A: This is a traditional method of soap production in which, as the name implies, the soap is boiled in a pot. It is sometimes referred to as the "saponification and salting-out method." The oil and fat are heated in a pot, stirred, and then combined with a caustic soda (sodium hydroxide) solution, which breaks down the oil and fat molecules into fatty acid and glycerin. The fatty acid bonds with sodium, and soap is produced. This process is called "saponification." After saponification, natural salt is added and the soap and impurity separated out. Salting out and still standing help the unsaponificates to react. This is followed by a final round of salting out that removes as many potentially irritating components as possible. Pot boiling method is a soap production method that has been passed down from generation to generation.

    Pot boiling method
  • Q:What are the advantages of soaps made by pot boiling method? A: The natural moisturizing factor, Glycerin, which is originally contained in the natural oil and fat used as raw material, remains moderately in the soap body. It will not strip away even necessary sebum that protects the skin and relieve the tight and dry feelings after washing. Soap is the only cleaning agent contained and it will rinse off the dirts and waste products quickly. Also, the cleaning agent will not remain on the skin. It will give a fresh feeling after washing and remove oiliness.
  • Q:What is the difference between the "milling method" and the "frame kneading method"? A: he milling method is the process of drying, mixing, kneading, and finishing scooped-up soap body using a machine in a short time. The frame kneading method, on the other hand, produces soap by pouring liquid-state soap into the frame, cooling, solidifying, and cutting it, and finally drying the cut blocks for up to about 60 days. Soap produced by the milling method is somewhat likely to crack and melt but can be offered at a low price. Soap processed by the frame kneading method is less apt to crack and melt because the water content and other substances are volatized and, as a result, crystals increase in density at the stage of drying and aging. Transparent soap, in particular, becomes harder and more transparent at the stage of drying and aging.
    Milling methodFrame kneading method
  • Q:What does "non-additive" mean for Non-Additive Soap"? A: It means that it is free of synthetic surface active agents, mineral oils, perfumes, colorants and preservatives. Our Non-Additive Soap Bar is produced from soap body boiled by the traditional pot boiling method and is blended only with natural vitamin E (labeled as Tocopherol, antioxidant) extracted from soybeans.
  • Q:Additive-Free Soap Bar does not contain any preservative. Isn’t there any problem with its quality? A: The pH values of Matsuyama’s bar soaps, including Additive-Free Soap Bar range from 10.0 to 11.0. One of the causes of the rotting of things is the development of microorganisms, and ordinary microorganisms can come into existence and grow at a pH value between 3.0 and 10.0. The reason our bar soaps do not get rotten although additives are not used is that their pH values are 10.0 or higher.
  • Q:Can I use Additive-Free Soap to wash my hair? A: Matsuyama’s bar soaps, including Additive-Free Soap, are available for shampooing. You may, however, feel creakiness or coarseness peculiar to soap. We hear that persons often feel something different in the feel of use from synthetic shampoos when they shampoo with soap for the first time. Please see the following page for advice about how to use bar soaps. Although bar soaps and liquid shampoos are different in shape, they can be used in the same way. After shampooing, use a conditioner for soap shampoo, such as a PH Balanced Conditioner.
  • Q:Why do some soap products contain tetrasodium etidronate? A: Tetrasodium etidronate is an ingredient contained in solid soap products of Matsuyama as a sequestering agent. Soap contains water, which is one of the raw materials, as well as metallic ions (not metals themselves but metallic ions) introduced by the equipment used for making soap. Metallic ions gradually degrade the color or smell of soap over the course of time. The ingredient added to prevent this degradation is tetrasodium etidronate.
  • Q:Why is “soap” said to be “friendly to the skin and the environment”? A: Soap combines with the mineral contents (calcium, magnesium) in water to form soap scum (metallic soap), which has no cleansing power. Even when you are frothing up and using soap, part of it becomes soap scum, and all of it is transformed into soap scum when it is washed away with a large amount of water. Immediately losing its washing power by rinsing means that all factors that irritate the skin are easily lost. In addition, soap scum, even if discharged into the river as drainage, is finally decomposed into water and carbon dioxide in two weeks at the longest and does not impose excessive stress on the natural environment. This is the reason soap is a cleansing product friendly to the skin and the environment.
  • Q:What does the “maturation” of soap mean? A: The change of the crystal form inside the soap and the change of the soap resulting from the volatilization of moisture etc. in the drying process are called “maturation.”
  • Q:It is frequently said that acescence is good to the skin. You produce alkalescent soap products, and can we use them without any problems? A: No problem. The skin has the function of naturally returning to acescence by secreting sweat or sebum (neutralizing capacity). In addition, the skin immediately returns to acescence with the aid of an acescent skin lotion (most skin lotions available on the market are acescent products). For reference’s sake, the great majority of hot springs in Japan are neutral to alkalescent. Alkalescent ingredients function to soften and remove old keratin and lipid peroxide adhering to the surface of the skin. This is the reason you can feel your skin smooth and the metabolism of the horny layer is accelerated after bathing in a hot spring.
  • Q:What are the differences between bath soap (for face), kitchen soap and laundry soap? A: All soap products comply with the relevant regulatory requirements. The body soap is designed in compliance with the Act on Securing Quality, Efficacy and Safety of Pharmaceuticals, Medical Devices, Regenerative and Cellular Therapy Products, Gene Therapy Products, and Cosmetics (previous Pharmaceutical Affairs Law), soaps that are made to wash other than face and body such as laundry soap and furniture cleaner are produced in compliance with the Household Goods Quality Labeling Law (under the jurisdiction of Ministry of Economy, Trade and Industry).
  • Q:Why does transparent soap become soft when it is left in the bathroom? A: All soap products comply with the relevant regulatory requirements. The body soap is designed in compliance with the Pharmaceutical Affairs Law, soaps that are made to wash other than face and body such as laundry soap and furniture cleaner are produced in compliance with the Household Goods Quality Labeling Law (under the jurisdiction of Ministry of Economy, Trade and Industry).
  • Q:Can I remove makeup by soap? A: Our soap bars including "Kamadaki" Framed Soap Bar can remove almost all makeup. However, some products such as waterproof foundations and oil mascaras are hard to remove completely. In such cases, we recommend you to use a makeup remover instead.
  • Q:Which kind of soap is available for persons with atopic disease? A: Unfortunately, there are no soaps and cosmetics we can recommend to those who are suffering from atopic dermatitis or other skin problems. This is because all cosmetics, including our products, may cause irritation and should not be used when users are suffering from skin problems. Or, in some cases, it is necessary to ask advice of a dermatologist about, for example, how to use cosmetics. You may, however, try soaps and cosmetics if you do not develop any symptoms and the condition of your skin is relatively good.
  • Q:Can Recycled Framed Soap be used to wash body? A: No, it cannot be used for body. It is designed for kitchen use.
  • Q:Can you give me some tips on how to use the M Mark series Kitchen Liquid Soap? A:
    1)We recommend you to wipe off the oil stains with cloth or paper after working with meat and fish. It is also recommended to use rubber spatula to remove stains.
    2)Before you wash, rinse the stains lightly with water or lukewarm water.
    3)Moisten the sponge, apply soap and lather up well.
    4)Rinse in running water.
  • Q:Please tell me the difference between “Liquid Soap for Laundry” and “Powder Soap for Laundry.” A: The feature of “Liquid Soap for Laundry” is that it can be completely dissolved into cold water and is easy to froth up. On the hand, “Powder Soap for Laundry” is likely to be left undissolved into cold water, but is dissolved well into lukewarm water (20 to 30℃) equivalent to remaining water in the bathtub and exhibits its washing power. In addition, “Powder Soap for Laundry” can thoroughly remove contamination with a smaller amount of “Liquid Soap for Laundry” because it is blended with an alkali aid, which keeps the washing solution alkaline, and a water softening agent, which combines with mineral contents to improve the washing power of the soap. Considering these properties of the two soap products, Matsuyama recommends “Powder Soap for Laundry” when daily clothes are washed in a washing machine and lukewarm water of 20℃ or higher (at which Powder Soap is dissolved well) is available in terms of washing power and economy, or “Liquid Soap for Laundry” when only cold water is available or clothes are washed by hand. The standard amount to be used is displayed on both products, but the optimum amount of soap is slightly different depending on the degree of contamination of laundry and water hardness. The amount of soap is appropriate if it is put into water (lukewarm water) and the froth forms up to the surface of the water when the washing drum is turned on. In addition, if the froth has disappeared in the middle of washing, it indicates that the amount of soap was small relative to contamination. In such a case, add about 15 to 30mL of “Liquid Soap for Laundry” to let it forth up, and continue washing the clothes.
  • Q:Can your Laundry Liquid Soap and Laundry Powder Soap be used to wash clothes made of wool and silk? A: Our Laundry Liquid Soap and Laundry Powder Soap are formulated for cotton, linen, rayon, and synthetic fiber. They are alkalescent washing agents and different from neutral detergents for wool and silk in applications and suitability.
  • Q:Are "Powder Soap for Laundry" and "Liquid Soap for Laundry" available for a drum type washing machine? A: From experience, our "Powder Soap for Laundry" and "Liquid Soap for Laundry" are available for drum type washing machines. Both of the powder and liquid soaps, however, may clog any of the mechanisms or components of such washing machines depending on how they are used, and, as a result, cause water leaks or machine failures. For this reason, washing machine manufacturers generally caution users "not to use powder soap for drum type washing machines." They also give precautions about the use of liquid soap. Before using powder or liquid soap for your drum type washing machine, carefully read the instruction manual for the washing machine to see if the soap is available. Instructions about the use of powder and liquid soaps for drum type washing machines are describes below. If you find it difficult to follow them, we strongly advise you to use the detergent recommended by the washing machine manufacturer, not powder and liquid soaps.
    ■ How to use powder and liquid soaps for a drum type washing machine
    1)Do no put powder soap from the detergent inlet.
    2)Liquid soap can be put from the detergent inlet, but do not fail to pour hot water after putting it.
    3)Use a smaller amount of soap than usual.
    4) Use hot water for washing and the first rinsing.
  • Q:Please tell me how to use Laundry Powder Soap. A:
    1) Soap exhibits its high washing power when it is dissolved well into water and frothed up. Dissolve soap well into lukewarm water (20 to 30℃) equivalent to remaining water in the bathtub and froth it up for use.
    2)Pour a small amount of lukewarm water into the washing drum, and sprinkle Laundry Powder Soap into it. Stir the lukewarm water for about two minutes until sufficient froth forms, and add lukewarm water to the specified level.
    3)If an excessive load of laundry is washed at a time, it cannot be uniformly washed and will cause yellowing or an odor. Reduce the load of laundry to about 80% of the washing drum, and the washing drum will be able to rotate well and the soap content will spread to every part of the laundry.
    4)If the amount of soap is small relative to contamination, the froth will disappear. In this condition, contamination cannot be thoroughly removed. Add about one-fourth cup (50 mL) of Laundry Liquid Soap, which can be completely dissolved even if it is added later, to check the froth.
    5)Wash the clothes with running water. It is effective in preventing soap scum removed from them from adhering to them again. Much running water is not required. Adjust the amount of water so that the soap scum floating on the surface can be washed away.
    6)Immediately hang out the dewatered laundry to dry. Sunlight and air can prevent odors and yellowing. To prevent mold inside the washing drum, keep the lid open to dry the inside of the washing machine.
  • Q:Can I reuse the leftover water in which bath salt, bath sugar or bath essence is dissolved for laundry? A: You can reuse it for laundry but do not use it for washing white clothes or delicate clothings. We recommend you to use fresh water for rinsing. Do not leave the clothes in the leftover bath water for a long time.
  • Q:Can I use a softener? A: There is no problem in using softener but by washing the laundry with a soap, you will achieve a soft finish even without a softener. There is no need to use a softener.