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Washing-up liquids

the Science and technics
 
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the First soap, the most simple washing-up liquid, has been received in the Near East more 5000 years ago. First it was used mainly for washing and processing of ulcers and wounds. And only since I century d.C. the person began to wash with soap.

As Washing-up liquids are called natural and synthetic substances with clearing action, in particular soap and the detergent powders applied in a life, the industry and service sphere.

Soap receive as a result of chemical interaction of fat and alkali. Most likely, it has been opened on mere chance when over a fire fried meat, and fat has flown down on the ashes possessing alkaline properties.

Soap Manufacture has an old story, and here the first synthetic washing-up liquid has appeared only in 1916. The invention of German chemist Fritsa Pontera intended for industrial use, the household synthetic washing-up liquids more or less harmless to hands, began to let out in 1933. Since then variety of synthetic washing-up liquids (CMC) narrow appointment has been developed, and their manufacture became the important branch of the chemical industry.

Liquid Molecules are kept together by forces of an attraction. These forces pull the top molecules inside, and the liquid surface is bent. This effect named a superficial tension, is well visible on an example of almost spherical drop of the water which are slipping out the crane.

Because of a superficial tension water in itself does not possess sufficient cleaning action. Coming into contact to a stain, water molecules are drawn instead of grasping dirt particles to each other. In other words, they do not moisten a dirt.


Active substances

Soap and synthetic washing-up liquids contain the substances raising moistening properties of water at the expense of reduction of force of a superficial tension. These substances are called as surface-active (HAVING fallen), as operate on a liquid surface (all borders, not only top mean).

It is possible to present Molecules of PEAHENS in the form of tadpoles. Heads they "чхяы ¦=ё " for water, and tails - for fat. When PEAHENS mix with water, its molecules on a surface are turned "уюыютрьш" downwards, and them "§тюё=шъш" stick out of water. "ррчфЁюсшт" thus the water surface, these molecules considerably reduce effect of a superficial tension, thereby helping water to get into a fabric. The same tails of a molecule of PEAHENS grasp particles of fat coming across to them.

If fat has strong stuck to a fabric, for its removal it is required not only action of PEAHENS, but also a strong shake-up. Tiny droplets of the fat, covered HAVING fallen, dissipate in water, forming emulsiju.

PEAHENS share on kationnye, anionnye and neionogennye. Molecules kationnyh PEAHENS in a solution form positively charged ions, anionnyh - negatively charged, and molecules neionogennyh do not form PEAHENS of ions.

In all kinds of soap of PEAHENS - anionnye while synthetic washing-up liquids contain anionnye, kationnye or neinogennye PEAHENS (or a combination of two or three types).


Soap

Soap receive at reaction of fats (for example, coconut or palm-oil) with alkali - kausticheskoj soda (gidroksidom sodium) or kausticheskim potashem (gidroksidom kalija). The given chemical process is called omyleniem.

Soap On a modern soap factory of continuous action initial materials mix up and under pressure heat up to 130 "Р. As a result of reaction soap and glycerine are formed. After glycerine branch the fused soap passes the further processing.

Firm grades receive, drying up a tape of the fused soap, adding dyes and otdushki and pressing ready weight in pieces. Toilet soap becomes from more high-quality fats; after drying it heat up for moisture content reduction.

Soap flakes make as follows: to soap allow to harden on an outer side of a drum and soskrebajut it. To receive the soap powder, the fused soap mix with the additives improving its clearing action, appearance and a structure of a processed moistened fabric. A mix then dry up hot air. The same additives are used in synthetic washing-up liquids.

Many synthetic washing-up liquids are made today as in the liquid state, and in a powder. The powders containing 20-25% of PEAHENS, also receive drying of a semi-fluid mix. Some detergent powders contain the enzymes splitting fiber helping otstiryvat of a stain of substances with an albuminous basis - for example, blood or egg stains.


CMC

CMC Liquid synthetic washing-up liquids receive, adding to the dissolved mix of hydrotracks - substance which prevents stratification because of different density of components.

Synthetic washing-up liquids are included also into structure of cleaning powders necessary in housekeeping and pastes. Usually cleaning powders contain anionnoe PEAHENS, tonkoizmelchennyj a mineral (for example, feldspar) and a chloric bleach. Various special means are made for the industrial purposes. For example, mixes from neionogennyh and kationnyh PEAHENS are applied in the food-processing industry to washing and equipment cleaning according to the most rigid sanitary-and-hygienic requirements.