slide 3

• Some researchers believe that the word "cosmetics" comes from the Latin word "cosmetae". So in the Roman Empire they called slaves, whose duties included bathing masters in baths with incense.
• The word "cosmetics" was first used in 1867, during the International Exhibition in Paris, where the perfume and soap industries exhibited their products separately from the pharmaceutical industry. Soon the symbiosis of perfumery and soap making turned into a separate industry, which we now call the "cosmetics industry". Not to be confused with cosmetics.

slide 4

In the modern world, a wide variety of products are included in the list of cosmetics:

• Creams, emulsions, lotions, gels and oils for skin (hands, face, feet, etc.)
• Face masks (excluding chemical peels)
• Skin coloring bases (liquids, pastes, powders)
• Powders, hygienic powders, powders after baths
• Toilet soap, scented soap, etc.
• Perfume, toilet water and cologne
• Bath and shower products (salts, foams, oils, gels, etc.)
• Hair removal products
• Deodorants and sweat products
• Hair care products
• Hair dye and also for hair bleaching
• Products for curling, straightening and fixing hair
• Fasteners
• Cleansing products (lotions, powders, shampoos)
• Conditioners (lotions, creams, oils)
• Hair styling products (lotions, varnishes, diamonds)
• Shaving products (creams, foams, lotions, etc.)
• Products for make-up (powder, foundation, mascara, blush) and make-up removal from the face and eyes
• Lipsticks and lip care products
• Toothpastes and dental care products
• Nail care products, nail polishes
• Personal care products
• Tanning products
• Sunless tanning products
• Skin whitening products
• Anti-wrinkle products, etc.

slide 5

• Each country has its own list of cosmetics, fixed by law. So, in some countries soap does not apply to cosmetics. In Russia, the list of cosmetics includes essential oils, the main tools of Aromatherapy.
• In the modern world, there has been a trend of convergence of cosmetics with pharmaceuticals. Appears the new kind cosmetics, which is a mixture of cosmetics and medicines. This direction is called "cosmeceuticals". However, many countries, and in particular the United States, consider this direction in the development of cosmetics dangerous for human health. And they demand that manufacturers clearly separate medicines and cosmetics.

slide 6

History of cosmetics

• The history of cosmetics as a skin care product is little explored. The Roman physician Celsius (Celsius) in his books showed an active interest in skin and hair care, Pliny the Younger and the Roman physician Dioscorides, in addition to chemistry, devoted much space in their works to cosmetic preparations, and Claudius Galen, whose works cover many areas of medicine and pharmacy art, he is also known for inventing "ceratum refrigerans" - literally, a cooling ointment or cold cream, which is now known as "coldcream". The Romans used it as a make-up remover. In the scientific literature of that era, there are close links between medicine and cosmetics.
• The ancient Romans knew how to get rid of wrinkles with the help of astringent mixtures, wore artificial teeth, artificial eyebrows and artificial eyelashes.

Slide 7

History of decorative cosmetics

• Unfortunately, contemporaries, speaking about the history of decorative cosmetics (make-up or make-up), "try on" it to our time, and all explanations are based on a modern vision of the role of cosmetics in human life. Ancient Egyptian images of pharaohs with lined eyes for modern man they talk about "coquetry" and look like the pharaoh's desire to "please" his subjects. As if the pharaoh was not the ruler of vast lands, but a modern model posing for cameras. In fact, eyeliner was a necessary attribute of survival and protection from evil forces. Leading up the eyes, the ancient Egyptians drove away evil spirits, which, as he calculated, tend to penetrate into the soul of a person through the eyes. The fragrant oil cones that the ancient Egyptians wore on their heads also had nothing to do with cosmetics or perfumes. Living in a humid and hot climate, the ancients protected themselves in this way from the rays of the scorching sun and insects.

Slide 8

• The inhabitants of ancient Rome were well versed in the art of makeup. They actively used kohl (charcoal) as eye paint, fucus (focus), mostly red, for cheeks and lips, wax as a hair remover, barley flour and oil for acne, and pumice for for teeth whitening. They also dyed their hair black or blonde, depending on the fashion trends.
• Therefore, what we are now accustomed to seeing in the form of cosmetics, that is, as a means to improve the appearance, appeared relatively recently, a little more than one and a half thousand years ago. The ancient Greeks are lovers and connoisseurs of fragrances and cosmetics, it was they who revived the ancient Egyptian traditions of painting the face, but not as something vital, but solely for aesthetic purposes. By the 4th century AD, the Greeks were removing body hair, lined their eyebrows, applied white foundation to their faces, painted their lips, brushed their teeth, chewed gum, and dyed their hair golden. Following them, other peoples began to decorate the appearance. We now call this process "make-up" or "applying make-up."

Slide 9

• In Europe during the medieval period, it was fashionable to have pale faces. Rich people, who had no need to work outdoors and expose their faces to a tan, emphasized their wealth precisely by having a pale complexion. Spanish prostitutes, on the contrary, painted their faces pink, thereby emphasizing their difference from the pale-faced women of high society. In the 13th century, women of the royal family used pink lipstick to demonstrate their belonging to the highest power.
• During the Italian Renaissance it was fashionable for women to paint their faces with white lead. Of course, lead is harmful to human health, but unlike arsenic powder, it was not used as a poisonous substance. At that time, a powder called AquaToffana was widely known in Italy, named after its creator, Signora Toffana. This powder was intended only for women from wealthy families. The powder container contained an invitation to the client to visit Signora Toffana for instructions on how to apply the powder. During the visit of a woman, Signora Toffana explained to her that powdering her cheeks should be done only when her husband is nearby, and nothing else. As a result, with the assistance of Signora Toffana, six hundred husbands went to another world and the same number of "unfortunate" widows continued to live on the sinful earth.

Slide 10

• In Elizabethan England, cosmetics were considered unhealthy because it was believed that they did not allow moisture to evaporate naturally and interfere with the normal release of energy. During the French Restoration of the 18th century, red rouge and lipstick personified passion, fury, and their owners were considered healthy, cheerful people. This was the case in France, however, many people in other countries had a negative attitude towards excessive use of cosmetics. Opinions were often expressed that the French made up cause disgust, because they have something to hide.
• In the 19th century, decorative cosmetics gradually began to enter into everyday life, then these were already means of natural tones, with the help of which a healthy ruddy color was given to faces. But even then, the excessive use of cosmetics was perceived negatively and was seen as sinful.
• The Victorian pale face remained in fashion until the 1920s, until the time when mass production and widespread trade in cosmetics began. In the 60s of the XX century, there was a sharp turn in the decorative design of the face: instead of white lips and Egyptian eyes, fantastic images came into fashion, for example, a butterfly painted on the face. Such a "decoration" was in honor during out-of-town walks of high secular society. Until the late 70s, early 80s of the twentieth century, looks with pronounced eyeliner of various colors and shades remained in fashion.

slide 11

The composition of cosmetics

• Cosmetics is a chemical formula made up of chemicals, ingredients. The composition of one cosmetic product can include more than 50 ingredients. Each ingredient has a specific function in the composition of the chemical formula of cosmetics. The same ingredient can have multiple properties. In turn, all the ingredients are divided into groups:
• Abrasives Absorbents Additives Anti-corrosion agents
• Anti-dandruff agents Defoamers Antimicrobial agents Antioxidants
• Antistatic agents Binders Biological additives Bleach agents
• Herbal Additives Buffer Agent Chelating Colors Denaturants
• Hair removers Skin softeners Emulsifiers Emulsion stabilizers
• Film-forming Foaming Fragrances (perfumes) Hair dyes
• Humidifiers Contrasters Oxidizers Pigments Preservative
• Various gases Reducing agents Solvents Surfactants or surfactants
• UV absorbers (solar filters) Viscosity adjusters

slide 12

• When compiling the chemical formula of cosmetics, many aspects are taken into account: it must attract customers with its aroma and consistency, be convenient and easy to use, and most importantly, fulfill its main purpose - to improve appearance, give freshness and beauty to the face, body, hair, nails, etc. e. In order to meet all the requirements, many substances are added to the chemical formula that are not related to its main purpose - to care for the appearance. The inclusion of additional substances in the composition of cosmetics is due solely to marketing considerations. These include anti-corrosion agents, antistatic agents, binders, contrast agents, viscosity regulating agents. The addition of emulsifiers, for example, is due to the need to mix substances that are immiscible in nature - fats and oils and water, otherwise the cosmetics will not have a marketable appearance, will spread and delaminate.
• Preservatives also have nothing to do with skin care. They serve to ensure that cosmetics retain their marketable appearance for as long as possible: they do not exfoliate, do not lose consistency, do not change color and smell. The main purpose of preservatives is to prevent the growth of harmful microorganisms that can lead to various diseases. If cosmetics contain water and fat, two preservatives are usually added to such cosmetics - to protect the water part and to protect the fatty part of the cosmetics. The so-called preservatives are mainly used as preservatives. "parabens". Only in Russia they continue to use the toxic carcinogen Bronopol and its derivatives as a preservative. Moreover, it is even added to cosmetics for children.

slide 13

Dangerous ingredients in cosmetics

• Unfortunately, harmful ingredients and impurities in cosmetics are much more common than we would like, and some of them pose a real threat to health. Notorious among these are: 1,4-dioxane, nitrosamines, and chemicals that affect the endocrine and hormonal systems.
• "Genderbenders" (literal translation: "a substance that can change gender").
• In a modern industrial society, a large number of chemical compounds are released into the environment, which have a negative impact on human health, and in particular on the endocrine system and change the hormonal background of the body as a whole. These substances are called ecoestrogens. They get into cosmetics and food products from plastic packaging. Ecoestrogens are also found in detergents as surfactants and antioxidants, and are used in cleansers, cosmetics, toiletries, and foods. For example, BHA (butylated hydroxyanisole, Butylated hydroxytoluene) is used as an antioxidant. Substances belonging to the group of phthalates: dibutylphthalate (dibutylphthalate), di-2-ethylhexylphthalate (di-2-ethylhexyl phthalate), di-isopropylphthalate (di-isopropylphthalate) and benzylbutylphthalate (benzylbutylphthalate). Their danger lies in the fact that they tend to accumulate in the tissues of the human body, and over time, the level of their content becomes higher and higher, which can affect the functioning of the endocrine system.

Slide 14

• Dioxane (1,4-dioxane) Dioxane (1,4-Dioxane)
• This substance is a well-known carcinogen (cancer-causing substance). 1,4-dioxane was created by accident as an undesirable by-product in the manufacture of some cosmetic ingredients - when two molecules of ethylene oxide combine during a side chemical reaction. Before an ingredient can be used in cosmetics, this chemical compound must be carefully removed by evaporation under vacuum. Ethylene oxide (ethylene oxide) is also used in cosmetics as a surfactant, emulsifier and film former. In the composition of cosmetics, it can be distinguished by name: PEG, polyethylene glycol (polyethylene glycol), polyoxyethylene (polyoxyethylene), as well as chemicals with the ending “-eth” (for example, the laureth family) or “-oxynol”.
• Nitrosamines (Nitrosamines)
• Nitrosamines, otherwise known as N-nitroso compounds, are aggressive carcinogens that can enter the human body through the skin. They are not used as ingredients in cosmetics, such as Dioxane. They can be formed by accident during the preparation of individual ingredients, or by the interaction of two absolutely safe ingredients in the final product. Even chemicals released from human skin can react with ingredients to form nitrosamines. Some ingredients are known to be nitrosating agents, for example: sodium nitrite (used as a corrosion inhibitor), some hair dyes, preservatives such as 2-bromo-2-nitropropane-1,3-diol (2-bromo- 2-nitropropan-1,3-diol) (BNPD or Bronopol - BNPD or Bronopol) and 5-bromo-5-nitro-1,3-dioxane (5-bromo-5-nitro-1,3-dioxane) (Bronidox with Bronidox). Therefore, well-known cosmetics manufacturers do not use these ingredients in cosmetics. However, these substances can be found in the composition of cosmetics, which are produced in Russia.

slide 15

Diseases caused by cosmetics

• Sensitive skin
• Many women who think they are allergic to cosmetics are actually suffering from irritation caused by one or a group of chemicals in cosmetics. Studies conducted in the EU have shown that 42% of women consider themselves to have sensitive skin. If the skin reacts quickly to the use of cosmetic products containing irritating components, then it is safe to say that it is sensitive skin. Often, symptoms such as itching, red spots, and sometimes a rash (urticaria) quickly disappear if the affected area is washed with water or a soothing lotion. As a rule, skin sensitivity is provoked by fragrances and coloring chemicals, as well as preservatives, sunscreens and many others, both natural and synthetic origin.
• Allergy
• An allergic reaction occurs when the body's immune system reacts with a substance that would not normally cause such reactions in other people. Allergy symptoms are: itching, swelling on the skin, rash. The appearance of simple allergic reactions can be avoided if you stop using cosmetics that cause a negative effect. You can determine such funds only after consulting a doctor or as a result of an allergic skin test.
• Acne and blackheads (comedones)
• Blackhead acne occurs when the hair follicles or sebaceous glands of the skin become blocked by an oily mixture of sebum (natural sebum) and keratin (the coarse fibrous protein that coats the skin, hair, and nails). This mixture hardens and turns into a cork, which turns black when exposed to air. If bacteria get into such plugs and gain the ability to multiply, then blackhead acne becomes infected and red pimples form - acne. One of the causes of acne is oily or fatty substances that penetrate into the pores of the skin along with cosmetics and clog them.

slide 16

• On September 1, 2009, the European Communities, with the participation of BDIH (Germany), BIOFORUM (Belgium), COSMEBIO & ECOCERT (France), ICEA (Italy) and SOIL ASSOCIATION (UK), adopted the standard (COSMOS-standard) for natural and organic cosmetics.
• The composition of natural cosmetics and cosmetics "organic" should include five types of ingredients: water, natural minerals, herbal ingredients that are obtained by physical and chemical methods, as well as other groups of ingredients.
• Cosmetics manufacturers that declare their products as natural are required to provide the following information: the origin and method of obtaining ingredients, the full composition of cosmetics, storage conditions, production and type and quality of packaging, environmental conditions, various certificates of conformity.
• It is forbidden to include nanomaterials in the composition of natural and "organic" cosmetics, use raw materials from genetically modified products, radioactive substances. It is also forbidden to test cosmetics on animals. However, such testing of ingredients is permitted, based on the laws of the country of origin.

Slide 18

• LONDON, 19 November. Every day, women apply an average of 515 chemical compounds to their faces as part of hygienic and aesthetic cosmetics, perfumes, etc. This is evidenced by the results of a study conducted by one of the manufacturers of cosmetic products, writes Telegraph.
• According to scientists, the average woman uses 13 facial cosmetic products every day, most of which contain more than 20 ingredients. Perfume products contain an average of 250 chemicals, and in some, this number reaches 400, Mednovisti reports.
• The study also found that the average number of ingredients in lipstick was 33, in skin lotions 32, in mascara 29, and in hand moisturizer 11.

Slide 19

• The long-term effects of many of these substances have never been studied, so it is possible that they may pose some health risk. In addition, previous studies have shown that a third of women under the age of 25 regularly use cosmetics intended for use after 40, which is harmful to their skin.
• Recall that earlier scientists from the United States found that up to 2.5 kg of various chemicals can enter the body of a woman who daily uses cosmetics - creams, masks, scrubs, foundation, powder, blush.
• Some artificial ingredients that the body absorbs cause side effects ranging from skin irritation to early aging and cancer.
• Richard Bence, a biochemist who spent three years studying cosmetics and perfumery, said: “It is vital to analyze the products that we put on the skin, and not just proclaim that their chemical composition is safe.” substances when mixed with each other. The consequences can be more serious than all the components separately," he explains.
• At the same time, the absorption of chemicals through the skin is much more dangerous than their ingestion.
• We also note that, according to the calculations of British researchers, a woman who paints her lips, from 14 to 80 years old, eats an average of 9 kg of lipstick.

Slide 20

http://ru.wikipedia.org/wiki/Cosmetics#.D0.A1.D0.BE.D1.81.D1.82.D0.B0.D0.B2_.D0.BA.D0.BE.D1.81 .D0.BC.D0.B5.D1.82.D0.B8.D0.BA.D0.B8

http://www.rosbalt.ru/2009/11/19/690271.html

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1 slide

2 slide

Written sources, excavations of ancient settlements testify that at an early stage of the development of society, both women and men were not indifferent to body painting. In men, this was especially manifested in a penchant for tattoos, and women tinted their eyelids, eyebrows, lips, and cheeks. Naturally, in the distant past, only natural substances were used as cosmetics. For example, eyelids were tinted blue with the finest pollen from crushed turquoise - a mineral having the composition CuO * 2Al2O3 * 2P2O5 * 9H2O, and eyebrows were dyed with soft natural minerals - antimony brilliance Sb2S3.

3 slide

The mother-of-pearl effect is created by bismuthyl salts BiOCl, BiONO3 or mica containing about 40% titanium oxide (IV) TiO2. Pearl, or Spanish, white has long been known, their main component is BiONO3, which are necessary for the preparation of white make-up. In the creation of makeup, zinc oxide ZnO is also used. As a hair dye, dilute aqueous solutions of highly soluble salts of lead, silver, copper, and bismuth are used. They are pre-impregnated with hair. The developer for the salts absorbed into the hair is pyrogallol.

4 slide

Metal ions are reduced to simple substances. Ammonia, which is part of the dye, neutralizes the resulting acid. Under the action of reduced copper, the hair acquires a reddish tint. If silver salts were taken - a gray tint, iron salts - a bluish-purple color. Coloring shampoos contain n-phenylenediamine, resorcinol and other similar compounds. Hair lightening is performed using a 3% solution of hydrogen peroxide, which decomposes with the formation of atomic oxygen (at the first moment). The oxidizing action of the latter is so great that it destroys the pigments of the hair. But with high concentration and prolonged exposure, the hair itself can begin to break down. You have to be very careful. In practice, hydrogen peroxide is used in the form of a complex with urea (NH2)2CO * H2O2, it is called hydroperite.

5 slide

With the help of "chemistry" you can not only change the color of the hair, but also give it a certain shape. It is known that hair retains its elastic properties due to the presence in its structure of numerous disulfide "bridges" (as in vulcanized rubber). If they are temporarily weakened, and then give the hair the necessary shape and fix it, we get a new hairstyle. In perm, the role of the destroyer of "bridges" is assigned to thioglycolic acid HSCH2COOH or its more stable salts. Subsequent treatment of the styled hair with compounds such as Cl-R-Cl (for example, dichlorobutane) restores "bridges", fixing new form hair. Cosmetics for nails are varnishes. The basis of nail polishes is a solution of nitrocellulose in organic solvents. Nitrocellulose is obtained by nitrating cellulose (cotton or wood) with a mixture of nitric and sulfuric acids. Acetic acid amyl ester, acetone, various alcohols, and mixtures thereof are used as solvents. In addition to the dye, plasticizers (for example, castor oil) are added to the varnish, which prevent the degreasing of the nails and prevent their fragility.

6 slide

Cosmetics for nails are varnishes. The basis of nail polishes is a solution of nitrocellulose in organic solvents. Nitrocellulose is obtained by nitrating cellulose (cotton or wood) with a mixture of nitric and sulfuric acids. Acetic acid amyl ester, acetone, various alcohols, and mixtures thereof are used as solvents. In addition to the dye, plasticizers (for example, castor oil) are added to the varnish, which prevent the degreasing of the nails and prevent their fragility. One of the most important cosmetic products for the face are powders. Cosmetic powders are multicomponent mixtures. They include talc, or kaolin, zinc and magnesium stearates, premium rice starch, zinc and titanium oxides, as well as organic and inorganic pigments, in particular.

7 slide

Powder is an excellent adsorbent of moisture (mainly due to kaolin). A thin layer of it is quite enough to absorb the secretions of the sweat glands operating in the normal mode. On a hot day, the powder clogs all the pores and causes harm. Talc gives the powder flowability and a sliding effect. Kaolin and oxides mask skin imperfections. In addition, zinc oxide has antiseptic properties. Starch gives the skin a velvety feel, and thanks to zinc and magnesium stearates, the powder adheres well to the skin and makes it smooth. The powder also protects against atmospheric pollution. That is why skillfully, without excess applied to the face, it not only improves the color and masks minor skin defects, but also protects it. Compact powder, unlike loose powder, contains binding additives: cellulose derivatives, higher fatty acids, waxes, polyhydric alcohols and their esters, mineral and vegetable oils. They make it possible to obtain briquettes of a certain shape during pressing, which retain their strength for a long time.

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Presentation on the topic: Chemistry in cosmetics

slide number 1

Description of the slide:

slide number 2

Description of the slide:

Written sources, excavations of ancient settlements testify that at an early stage of the development of society, both women and men were not indifferent to body painting. In men, this was especially manifested in a penchant for tattoos, and women tinted their eyelids, eyebrows, lips, and cheeks. Naturally, in the distant past, only natural substances were used as cosmetics. For example, eyelids were tinted blue with the finest pollen from crushed turquoise - a mineral having the composition CuO * 2Al2O3 * 2P2O5 * 9H2O, and eyebrows were dyed with soft natural minerals - antimony brilliance Sb2S3.

slide number 3

Description of the slide:

The mother-of-pearl effect is created by bismuthyl salts BiOCl, BiONO3 or mica containing about 40% titanium oxide (IV) TiO2. Pearl, or Spanish, white has long been known, their main component is BiONO3, which are necessary for the preparation of white make-up. Zinc oxide ZnO is also used in the creation of make-ups. Diluted aqueous solutions of highly soluble salts of lead, silver, copper, bismuth are used as a hair dye. They are pre-impregnated with hair. The developer for the salts absorbed into the hair is pyrogallol.

slide number 4

Description of the slide:

Metal ions are reduced to simple substances. Ammonia, which is part of the dye, neutralizes the resulting acid. Under the action of reduced copper, the hair acquires a reddish tint. If silver salts were taken - a gray tint, iron salts - a bluish-lilac color. Coloring shampoos include n-phenylenediamine, resorcinol and other similar compounds. Hair is lightened using a 3% solution of hydrogen peroxide, which decomposes with the formation of atomic oxygen (at the first moment). The oxidizing action of the latter is so great that it destroys the pigments of the hair. But with high concentration and prolonged exposure, the hair itself can begin to break down. You have to be very careful. In practice, hydrogen peroxide is used in the form of a complex with urea (NH2)2CO * H2O2, it is called hydroperite.

slide number 5

Description of the slide:

With the help of "chemistry" you can not only change the color of the hair, but also give it a certain shape. It is known that hair retains its elastic properties due to the presence in its structure of numerous disulfide "bridges" (as in vulcanized rubber). If they are temporarily weakened, and then give the hair the necessary shape and fix it, we get a new hairstyle. In perm, the role of the destroyer of "bridges" is assigned to thioglycolic acid HSCH2COOH or its more stable salts. Subsequent treatment of styled hair with compounds of the Cl-R-Cl type (for example, dichlorobutane) restores the "bridges", fixing the new shape of the hair. Varnishes are a cosmetic product for nails. The basis of nail polishes is a solution of nitrocellulose in organic solvents. Nitrocellulose is obtained by nitrating cellulose (cotton or wood) with a mixture of nitric and sulfuric acids. Acetic acid amyl ester, acetone, various alcohols, and mixtures thereof are used as solvents. In addition to the dye, plasticizers (for example, castor oil) are added to the varnish, which prevent the degreasing of the nails and prevent their fragility.

slide number 6

Description of the slide:

Cosmetics for nails are varnishes. The basis of nail polishes is a solution of nitrocellulose in organic solvents. Nitrocellulose is obtained by nitrating cellulose (cotton or wood) with a mixture of nitric and sulfuric acids. Acetic acid amyl ester, acetone, various alcohols, and mixtures thereof are used as solvents. In addition to the dye, plasticizers (for example, castor oil) are added to the varnish, which prevent the nails from degreasing and prevent their fragility. Powders are one of the most important cosmetics for the face. Cosmetic powders are multicomponent mixtures. They include talc, or kaolin, zinc and magnesium stearates, premium rice starch, zinc and titanium oxides, as well as organic and inorganic pigments, in particular.

slide number 7

Description of the slide:

Powder is an excellent adsorbent of moisture (mainly due to kaolin). A thin layer of it is quite enough to absorb the secretions of the sweat glands operating in the normal mode. On a hot day, the powder clogs all pores and causes harm. Talc gives the powder flowability and a sliding effect. Kaolin and oxides mask skin imperfections. In addition, zinc oxide has antiseptic properties. Starch gives the skin a velvety feel, and thanks to zinc and magnesium stearates, the powder adheres well to the skin and makes it smooth. The powder also protects against atmospheric pollution. That is why skillfully, without frills applied to the face, it not only improves the color and masks minor skin defects, but also protects it. Compact powder, unlike loose powder, contains binding additives: cellulose derivatives, higher fatty acids, waxes, polyhydric alcohols and their esters, mineral and vegetable oils. They make it possible to obtain briquettes of a certain shape during pressing, which retain their strength for a long time.

slide number 8

Description of the slide: