DEPARTMENT OF COSTUME DESIGN AND FASHION
NEHRU ARTS AND SCIENCE COLLEGE
THIRUMALAYAMPALAYAM
COURSE : III B.Sc (CDF)
SEMESTER : V
SUBJECT : CARE AND MAINTENANCE OF TEXTILES
UNIT : I
LECTURER NAME : B.SABINA ROSE
SYLLABUS
Water- Hard and Soft water, Methods of softening water, Laundry soaps- Manufacturing of the
soap(Hot and Cold process), Composition of soap, Types of the soap, Soapless detergents,
Chemical action, Detergent Manufacture. Advantages of Detergents.
PART –A
1. If the water content is in the range of 61-120 ppm, the water is said to be Moderately
Hard.
2. Spentlye is the by product formed in the manufacturing process of soap solution.
3. Oleic acid has the molecular formula of C17H33COOH.
4. Hard soaps cannot be rubbed easily on the surface to be cleaned by the lathers.
5. A Detergent is the cleansing action or the agent which is a solid or a liquid and it is
usually a synthetic preparation.
6. The term detergents means that “to clean”.
7. Zeolite process has the molecular formula of (Na2O)x.2(Al2O3)y.(SiO2)z.(H2O)n
8. The active ingredients in the soaps are commonly Non-ionic compounds and
sulphonated alkyl benzene.
9. Oleum is the derivative formed in the preparation of the petroleum by dissolving in the
Conc.H2SO4.
10. Sodium perborate and other optical brighteners are used to remove the stains and then
whitens the fabrics.
PART –B
1. Explain about Hard water and its hardness.
It is not only bad for the laundering process, it also makes the water harder to
wash the dishes, clothes and to bathe, to cook, shave and clean. The impurities that
cause the hardness in the water are harmful both in the manufacture and washing of
the fabrics. Most of the water may cause the hardness from the chalky dirts
containing the calcium / magnesium salts in the solutions of usually sulphates of
bicarbonates. Among the properties of water that makes it so useful for the washing
purposes and the ability of water to adhere to the fabric, so that it can penetrate it into
the fiber and wet it out. The movement of the water particles helps us to remove the
nongreasy dirt and the stains are then removed during the steeping process. Water
which is indispensable is the prime agent in the laundering. Our sources of water is
either through surface , sub soil or the deep soil.
Water that contains at least the traces of the calcium and the magnesium
in the form of bicarbonates and the sulphates, chlorides. Temporary hardness can be
removed by the heat without the use of the chemicals. The temporary hardness can be
caused by the bicarbonates and while the permanent hardness can be caused by the
chlorides and sulphates. All other compounds of calcium and magnesium namely
their sulphates and the nitrates causes permanent hardness . These salts are soluble
in the pure water and make this kind of the hardness more persistent. It can be only
removed by the distillation process or by the use of the chemicals.
2. Explain the composition of the Soap.
Soaps are the sodium salts of the fatty acids. The sources of these acids are the
animal and vegetable fats. The chief alkalies used are the caustic soda, potash etc. All
these soaps contains water but not more than 30% in the good soaps. Additives also
added to give the soap their specific properties. Other substances included in the soap
are the formation of silicates, starch, soap stones, which acts as a filling agents.
Naptha and a little mineral oil such as paraffin oil may be added in its cleansing
action and the removal of the greases. Resin also be added to increase the
effectiveness of the soap. Other additives include the disinfactants such as the
carbolic acid, solvents and the substances used for the filling the soaps are sodium
silicate, sodium carbonate.
They acts as both the detergents and the mechanical aids in the cleaning process.
The fatty acids which are commonly found in the nature are as follows.
(i)
Palmitic acid –C15H31COOH
(ii)
Stearic acid – C17H35COOH
(iii) Oleic acid – C17H33COOH
(iv)
Linolic acid C17H31COOH
The fatty acids are then formed by the combination of long chain fatty
acids with the glycerol formed as a byproduct. Animal fats are the tallow and
lard. Vegetable fats are coconut, cotton seed and mustard oils.
Starch in the presence of alkalies it combines with the water to form the soluble
gelatinous mass. Therefore it is used to give the firmness to the soap. Then this level deteriorates
the cleaning action of the soap. It is generally added to the level of 2%.
DETERMINATION OF CHEMICAL COMPOSITION OF THE SOAP USING
LAUNDERO METER
3. Explain about Soapless detergents and methods of its preparation.
A detergent is a cleaning agent which is a solid or a liquid which is also
a synthetic preparation. It then resembles the soaps in its cleansing action that is the
emulsification of the oils and holding of dirt in its suspension. It is also called as the
sulphonated fatty alcohols., which is used to reduce the surface tension of the water.
Detergents had the properties similar to the soap, such as the foaming, wetting and
cleaning but they are able to make soluble salts out of the calcium, magnesium and
other metals that make the water hard. In solution the detergents molecules arrange
themselves in a manner that the hydrophobic part of the molecule projects above the
water into air and the hydrophilic part projects down into the water. (i.e) at the
surface of the water in a washing tub or in the fabric itself. With the result, the
hydrophilic part of the all the detergents
molecules are densely packed below the surface of the water to bind the dirt in the
fabric. During the lathering and rinsing the detergent molecules with tightly held on it
and the dirt with grease comes out of the fabric into the fine suspension.
Fats such as coconut oil or free fatty acids reduced by the H2 gas in the
presence of the catalyst to form the fatty alcohols. It is then reacted with the sulphuric
acid to form the sulphonated fatty alcohols. These sulphonated fatty alcohols upon the
reaction with the alkali such as the caustic soda or with the potash are converted to
the soapless detergents. These soapless detergents is a long linear molecule , in which
its one end have the low affinity and the other had high affinity for the water
respectively.
Oil (or) Fatty Acid + Hydrogen gas----Fatty alcohols +H2SO4--Sulphonated fatty alcohols+NaOH (Or) KOH---- Soapless Detergents.
HYDROPHILIC PART – CH3
PART – OSC3Na
HYDROPHOBIC
4. Explain the Chemical action of the Detergents.
To see how soaps and the detergents do their cleaning, we can depict the
long organic chains of their molecules as a tail depicted as R, attached to a head. In
the soaps, which are the fatty acids , the hydrogen atom at the head of the molecule
has been replaced by a carbonyl group, COONa Or COOK , depending on whether
caustic soda or the caustic potash has been used. In one large class of the detergents
on the other hand, the COD metal head of the soap molecule is replaced by a head
consisting of the group of O-SO3-metal or the SO3-metal. If a small amount of the
detergent is dissolved in a droplet of the water, the molecules of the soap or the
detergent on the surface of the droplet arranges themselves so that the heads of the
molecule prints towards the centre, while the tail all sticks outwards like hairs. More
technically, the tail of the soap molecules is the hydrophobic and the head is
hydrophilic in nature. The free tail so created are so capable of hanging onto the dirt
which can then be rinsed away along with the detergents.
The chemical differences between the soaps and the detergents gives the lather
new properties. They can be also made to give much more foam than the soap. They
wet the fabrics more readily than the soap; they emulsify the oils with the water as
well as the soap in the certain cases , and they have the cleansing properties almost
equal to the soap.
CLEANING ACTION OF THE GARMENT USING DETERGENTS IN A
WASHING MACHINE
5. Explain the advantages of the detergents.
(i)
(ii)
(iii)
(iv)
(v)
(vi)
While soap may leave the soap deposits so that the clothes comes out stiff and
the grey, a soapless detergents will then remove all the deposits. As a result,
the clothes feel softy and fluffy.
Detergents are soluble in the cold water. So they are preferable to soap when
the water is cold . Wash is indicated as for the girdles, rubberized garments
and the fine fabrics.
Greater cleaning efficiency than the soap, as they do not combines with the
calcium, magnesium and other salts present in varying degrees in the water,
and others are not wasted then. All the detergents are then available for
washing purposes. By the some taken only one quarter to a half as much
detergent is then needed compared to the soap.
More effective than the soap against the acids, particularly the body acids.
They also washes effectively in an acid medium which is an advantage with
the girdles and slops for instance, that generally becomes impregnated with
the acid dirts.
More than one deep, clean water rinse in unnecessary. When it is expedient, to
omit the rinsing process, the tiny amount of the detergents left over and after
the efficient washing , will not weaken or discolour the garment dyeing during
the ironing or storage process.
The small amout of foam formed on the rinse water by the detergents does not
harm. Most of the detergents forms the foam readily., even at the low vary
concentrations and are easy to rinse out in the cold water as quickly as
possible.
PART –C
1. Explain the Zeolite Process in detail .
The Zeolites are the minerals consisting of the hydrated aluminium silicates of the
sodium, potassium, calcium and barium with the general formula
(Na2O)x.2(Al2O3)y.(SiO2)z.(H2O)n. It can remove both the temporary and the permanent
hardness of the water and it has the property of being able to exchange its sodium or other bases
for the another metal. Thus it is called as the “Base Exchange process.”
When the hard water passes through the zeolites, the hardening components of the
calcium and magnesium are then caught up by it and become the compounds of the sodium.
Na2O.Al2O3.SiO2.H2O+Ca(HCO3)2---CaO.Al2O3.SiO2.H2O+2NaHCO3
Na2O.Al2O3.SiO2.H2O+CaSO4-- CaO.Al2O3.SiO2.H2O+Na2SO4
Na2O.Al2O3.SiO2.H2O+Mg(HCO3)2--- MgO.Al2O3.SiO2.H2O+2NaHCO3
Na2O.Al2O3.SiO2.H2O+MgSO4--- MgO.Al2O3.SiO2.H2O+ Na2SO4
Since these sodium salts do not precipitate out on the heating or the form soap curds,
then the water is called as the soft. However, the zeolite can exchange its base again and take
back the sodium in the place of calcium and magnesium and this process is then called as the “
Regneration”. It is then effected by passing a strong solution of the sodium chloride (Common
Salt) through the zeolite plant. The frequency of the regeneration depends on the amount of the
water which passes through the water softener.
CaO.Al2O3.SiO2.H2O +2NaCl---Na2O.Al2O3.SiO2.H2O + CaCl2 (Gas )
When the zeolite finally deteriorates, it has to be replaced with the fresh zeolite . At the
household level the zeolite process is mostly practical and then it is economical. For the domestic
purposes, it can be either connected to the main water supply or fixed to a water tap. It is an
attachment that is fitted into the plumbing system at the point where the water supply enters the
house. A domestic appliance can operate for the several days without the need for the
regeneration. However this system is so expensive when the source of the water is extremely
hard.
ZEOLITE PLANT ATTACHED IN THE INDUSTRY
The zeolites after attached in the industry helps to converts the base from calcium to the sodium
form so that the hardness of the water molecules reduces to 50-60 ppm. Thus by reducing the
water hardness present in the water it can be used for the other purposes where the water is
abudantely found somewhere.
2. Explain the Manufacturing Process of Soap in detail.
Soaps are the sodium salts of the fatty acids. The making of the soap is carried out
by the two major methods. They are as follows:
(i)
Hot Process or Saponification method.
(ii)
Cold Process.
Usually the laundry soaps and the toilet or bath soap are manufactured by using
the hot process. Transparent and other special types of the soap are produced by
the cold process. In most of the cases, soap obtained by the hot process is settled
or grained or separated from the spentlye containing the glycerol in its solution.
Then the glycerol is recovered as the by-product of the soap industry.
HOT PROCESS:
Saponification is the process which takes place when the fat is acted upon the caustic
alkalies. The fat is splitted up into the fatty acids and a glycerine and then the fatty acid
combines with the alkali forms the soap. This method is generally carried out on a large scale. It
then consists of the following steps:
(i)
Fats, Oil and caustic soda are then purified. The natural fats are melted, the impurities
are allowed to settle down and thus the clean fats are pumped into the kettle.
(ii)
A weak solution of 10-15% of caustic soda is added gradually and the mixture is then
boiled by the steam passed directly into the soap kettle.
(iii)
Some of the fat is saponified and then the soap is formed. More caustic soda solution
is added at the regular intervals and the boiling for 2-3 days is continued until the
saponification reaction is about 95% complete.
(iv)
The contents of the soap kettle are the soap, excess glycerine, caustic soda and other
impurities. Brine solution (NaCl) is added which separates out the soap, a thick liquid
soap rinses to the top. The liquid under this layer contains the glycerine, the unused
alkalies and impurities called as the spentlye.
(v)
Then the spentlye is taken out and the glycerine is distilled and stored in the kettle.
(vi)
Soap is again boiled with more water or the steam and let to stand until the four layers
are formed. The top layer is just froth and skimmed off. The second layer is the
genuine soap which is tapped out of the kettle by means of the pipe to the crutcher, a
mechanized mixer. The third layer is called as a Nigre consists of the impure dark
coloured soap solution and the fourth layer is the alkaline liquid.
(vii)
In the crutcher, colour, perfumes or some adulterants are added. After thorough
mixing soap is run in to the cooling frames. Cooling may range from a few hours to 5
days depending upon the cooling frames used.
(viii) The cooled soap, which is in the form of the blocks is then cut by means of the
machine into the slabs and then into bars and tablets and finally stamped. It contains
about 30% water and then 60-64% of the combined fats.
COLD PROCESS:
It is a simple and quick method of soap making one of the oils is mixed with the caustic
soda. The heat given off by the mixture is then sufficient to carry out the process in a better way.
Then the well proportionate mixture is stirred well for the 24 hrs. The soaps produced are hard
and then contains the glycerine, free caustic soda. These soaps are cheap and forms the good
lather in the cold or in the hot water.
INGREDIENTS:
Caustic Soda -250 grams
Water -4 Cups
Gram powder -250 grams
Coconut oil-2 Kgs.
METHOD :
(i)
Dissolve the caustic soda in the water ,stand the solution in an earthenware pot for 4
hours.
(ii)
Mix the gram powder and the oil in the big bowl.
(iii) Add caustic soda solution to the mixture of the oil and gram powder a little at a time
and beat it thoroughly. Continue the beating till the mixture is of the thick
consistency.
(iv)
Pour the mixture in the moulds, and allow the soap to form and set it easily.
3. Explain the Types of the soaps in detail.
Soaps are broadly classified under the following two types : They are as
follows.
(i)
Hard Soaps
(ii) Soft Soaps.
(i)
HARD SOAPS:
It cannot be rubbed easily on the surface to be cleaned. They do not dissolve
easily in the water and does not give the free lather. So, more labour is required to clean
the dirty cloth. Examples of this kind of soap are bar soaps consisting of solid bars and
soap powder which include powdered soaps, borax perborate and silicates.
(ii)
SOFT SOAPS:
These dissolve readily in the water to give smooth lathers. (ex) Tiolet soaps
and soap flakes.
(a) TIOLET SOAPS :
These are the good quality soaps free from the alkalies, which harms the
skin easily. Good quality soaps have a hard polished texture and are delicately
coloured and then scented (ex) Bathing soaps.
In addition, carbolic soaps, with the antiseptic agents are then available in
the market and are used in the hospitals. Other types includes the sulphur, tar
for the treatment of the skin diseases. (ex) dettol soaps and the Niko etc.
(b) SOAP FLAKES:
They also do not have any free from the alkalies, resins or any other
bleaching agents. They are easily soluble in the water than other soaps and the
powders and more suitable for washing of the delicate fabrics. Other
classifications are as follows;
(c) WASHING SOAP:
It is prepared from the tallow, resins, greases, palm oils and it is the
cheapest soap and are used by the big textile mills and in the commercial
laundries. It is generally hard in nature.
(d) SHAVING SOAP:
It is the type of the toilet soap. In this KOH is then added instead of the
NaOH. It results in the free lathering qualities and the lather lasts very longer.
(e) LIQUID SOAP:
Oils of the high iodine value are then used to make this type of the soap
to be used in the industry.
(f) SOAP POWDER:
To get the soap powder the hot concentrated solution is then mixed
with the soda ash and then allowed to cool. On cooling it becomes harder. It is
then pulverized in the mills to form a fine dust. This powder is then used for
washing the costly garments. Lux soap powder is an example of this type of
the soap used.
COURSE : III B.Sc (CDF)
SEMESTER : V
SUBJECT : CARE AND MAINTENANCE OF TEXTILES
UNIT : II
LECTURER NAME : B.SABINA ROSE
SYLLABUS
Finishes – stiffening agents- Starch ( Cold water and Hot water starch ),Other stiffening Agents ,
Preparation of Starch. Laundry blues and their applications.
PART –A
1. A Finish is a process given to the fabric to improve its qualities such as appearance,
hand and drape.
2. Mercerising is the process which provides luster to the silk material.
3. Stiffening agents are used in the fabric to impart the crispness present in them.
4. Borax is the well known standard stiffening agent used in the cold water treatment by
applying the starch.
5. The Embossing is the finishing process which is used to produce the raised design of the
fabric.
6. Prussian Blue is the commonly used and it is mainly ferric ferrocyanide.
7. All the soluble glues which is used in the laundry is soluble in the concentrated
hydrochloric acid and dissolves easily in alkalies.
8. Yellow fabrics should not be blued as their colour will changes to greenish.
9. Bleaching should be done well in advance before the laundry blues are added to the
fabric.
10. Turpentine Oil is used in the Hot water starch for preparing the stiffeners used in the
laundering.
PART –B
1. How is Boiling water starch is prepared ? Explain with its ingredients.
INGREDIENTS:
Starch – 1 table spoon
Cold water – 2 table spoon
Borax- 2 table spoon
Wax- ¼ table spoon
Boiling water -500 ml
PROCEDURE:
Mix the starch in the cold water to form a smooth paste in a basin. Add the borax
and wax . the function of the borax is to make the starch resistant to the atmospheric
condition and the wax is added for allowing the easy ironing of the fabric. Both of these
ingredients are optional. Then pour the boiling water quickly all times , till the colour of
the solution is transparent. This stage the ingredients are then completed, bursting of all
the starch grains and their conversions to the jelly. A little bit of the formaline can be
added to this jelly to avoid the microbial spoilage.
APPLICATION TO FABRICS:
For the application to the fabrics, standard starch jelly is diluted with the cold water
to an extent depending upon the amount of stiffness required. When diluted with an
equal amount of the cold water , the solution is termed as the 1:1 starch. Following the
table summarized the strength to be used for the different clothings made up of the
cotton or linen.
2. How is Cold water starch is prepared ? Explain with its ingredients.
INGREDIENTS:
Rice Starch – 1 table spoon
Boiling water – 2 table spoon
Borax- ½ table spoon
Turpentine – 3 drops
Boiling water – 1 table spoon
PROCEDURE:
Dissolve the borax in the boiling water and then mix with the cold water. Pour
the mixture over the starch followed by the turpentine oil. Stir well till the viscous
solution is formed. Strain the starch solution through a muslin cloth and use after an half
an hour.
APPLICATION OF STARCH:
The rice starch is used to provide the great stiffness as that required for the cuffs
and collars. The fabric should be dry before the starching. The article is then kneaded
and squeezed in the starch solution. Then it is rubbed with the a muslin cloth to remove
the excess starch. The article is then wrung out tightly in the cold water. To achieve the
greater stiffness the standard article is then ironed with the quick movement when still
wet it out.
3. Explain about the Other Stiffening Agents in detail.
Borax can be used above for the slight stiffening agent of 1 to 4 teaspoonful are
added to the ½ pint of the water. Borax is useful for the stiffening laces. Dilute solutions
of the gelatin or the gum Arabic are then often used on the delicate fabrics like the
violes, organdies and the silks restore their crisp appearance.
Avoid using too much however, as they leave will the fabric, feeling sticky. First a
stack solution is made by adding 1 pint cold water to 1 ounce gelatin or the gum Arabic ,
and then continue the heating to dissolve. The stack solution can be then stored with a
little borax to help the preserve it. Before use, the stack solution is diluted with the hot
water. 8-15 times for the gelatin, 5-10 times for the gum Arabic. The actual dilution
depends on the kind of the material and the stiffness required.
4. Explain the Bluing process and its application.
Bluing is done at the last rinse of the fabric after washing. For this purpose care
should be given and it is taken that no soap is left in the fabrics before bluing. The blue
is tied in a muslin cloth and then squeezed in the cold water till the required colour in the
water is obtained. Insoluble blues tend to then settle down after sometime, therefore
before immersing the fabric everytime stirring is then required. The articles are dipped in
the solution one or twice, taking care that after taking out no solution is left there filling
in the pockets or the bag shaped parts. The blued fabric is then squeezed off the excess
solution and then dried. Bluing and starching can also be done simultaneously in a single
step when it is required.
Yellow fabrics should not be used and then blued as their colour changes to
greenish.
APPLICATION :
Dissolve the bluing in the last rinse. If the blue is in the powder form, it is better to
make a paste with the little water and add to the bath. Care is necessary to add the
proper amount of the bluing . The clothes should be dipped in immediately. Each item
must be dipped well and open out in the water to ensure the proper penetration. Then the
articles should be gently squeezed and then dried. It over blued then the cloth should be
soaked in the boiling water for 3 minutes and then dried. Today many detergents and
even starches and softens having the bluing incorporated in them.
PART –C
1. Explain about the Finishing process and explain its types in detail.
A finish is the process given to the fabric to improve its qualities such
as appearance, hand and drape. Most of the fabrics are given some finish or the other before
they leave the mill for the shop floor. There are the two major groups of the finishes . They
are the Physical and Chemical finishes.
PHYSICAL FINISHES :
(i)
Brushing / Shearing
(ii)
Calendering
(iii) Tentering
(iv)
(v)
(vi)
(vii)
(viii)
(ix)
(x)
Moireing
Embossing
Glazing
Weighting
Sanforizing
Schreinering
Wrinkled effect
CHEMICAL FINISHES :
(i)
(ii)
(iii)
(iv)
(v)
Mercerising
Crease Resistant
Fire Proof
Water Proof
Water Repellent
BRUSHING/SHEARING:
It is given to remove all the small fibres sticking on the surface of the cloth. Shearing
is done to smoothen the surface as well as even the pile. It has revolving blades similar
to the lawn roller
CALENDERING:
In this process the cloth is pressed by passing it between the heated rollers. If the
fabric is to receive a high polish the cloth is usually stiffened with the sizing before it is
calendered. The more the heat and the pressure is then applied, the greater the luster
produced. This process also adds luster to the fabrics.
TENTERING:
The process of the tentering straightens out the edges and the weaves of the fabrics,
and it makes even in its width. For this purpose, the tenter frame is employed and the
drying is then done by the machines, which either radiate heat from the steam pipes or
blow the hot air through the fabrics.
MOIREING:
Attractive, lustrous , wavy designs or the water line effect called as the Moire can be
produced by a process that is then essentially one of the minute surface embossing or the
pressing of the fabrics with the ridged rollers employed in it.
EMBOSSING:
The embossing calendar produces a either flat or the raised design on the fabrics. It
is then more popular in the heat sensitive fibers such as the Nylon, Acrylic
and polyester etc. The embossing machine consists of the two rollers, one of them is
then covered with the cloth and the other is engraved with the design. The engraved
metal roller is then heated from the inside by a gas flame.
GLAZING:
A stiff polished or the glazed surface can be obtained by the application of the
starch, glue , resin followed by the friction calendaring.
The friction calendaring is then used to give a highly glazed surface to the cloth.
The cloth is then first passed through the finishing solutions and then it is dried to a
certain degree of the dryness.
WEIGHTING:
It is given with the purpose to provide the filling in the silk and the wool. Depending
upon the nature of the fabrics, different types of the metallic salts are then used as the
filling agents. For silks, the weighting is done either at the yarn stage or to the woven
material. Commonly used weighting substances for the silks are tin, chloride and the
tennate which are then uniformly absorbed by the fibres.
SANFORIZING:
All the textile fibers are then made up of the fine threads. These threads during the
weaving process are then strained or stretched to the great extent. It is one of the process
to produce the unshrinkable fabrics in which the stretched threads in the weaving
process of the fabrics are recontracted without impairing their finish.
MERCERIZING:
In this process cotton fabrics are then exposed to the strong alkali solution under the
specific conditions which provides the silky luster, increased strength and then the
beautiful shine to the cloth. It also increases the affinity to the dyes and the colouring
materials. This treatment produces a permanent change in the structure of the cotton
fibers and provides the stability to their weave structures.
CREASE RESISTANT:
It is also referred to as the wrinkle resistant finish and is then given to the prevent
deformation of the fabrics by the undesirable and intentionally introduced folds. The
crease resistant is then largely decided by the construction and the fiber content of the
fabrics but this also achieved by the specific finishes which keeps the fabric flat and
strong.
WATER PROOF AND WATER REPELLENT:
A water proof fabric is one in which no water can penetrate inside it. A water
repellent fabric is resistant to the wetting but if the water comes with the enough force it
will penetrate the fabric. Water repellency is then dependent on the surface tension and
the fabric penetrability. To make the fabric water repellent wax emulsion, metallic soaps
and other surface active agents are used. To make the fabrics water proof these are then
coated with the pyroxylin. But this has been supplemented by the use of synthetic resins.
Water repellent property also depends upon the construction of the weave.
FLAME PROOF:
Inorder to make the fabric resistant to the fire, it is necessary to impregnate it with the
inorganic preparations so that it becomes incapable of supporting combustion. There are
many such preparation that makes the fabrics fire proof but these are not then permanent
and are affected by the water. One such agent is the organic borophosphate, which is
soluble only in the water. A flame proofing compound for the cotton fabrics consists of
chlorinated paraffin wax, synthetic resin, insoluble metallic oxides pigments and other
volatile solutions.
A simple home method can be used to make the fabrics fire proof. This is done by
immersing the fabrics in a solution of 7 ozs of the borax and 3 ozs of boric acid and in
the 2 quarts of the hot water. Wring and dry. Fire proof finish can also be created when it
the functions and as a fire extinguisher.
2. Explain Laundry blues ? Describe the different types of blues in detail.
Blue is used in the last rinse for the bleached cotton and linen. Blues are the
chemicals used during the wash cycle, either at the home or large laundries to remove the
yellow tint of the white fabrics which arises due to the repeated washings. It is obtained
from the chemicals, vegetable and the mineral sources and in the form of the powder, liquid
balls and the cubes. The colour varies according to the sources from the violet to blue or
from the greenish colour to the bluish green. They also differ in their stability and they are
highly insoluble in the water.
TYPES OF BLUES :
Depending upon their solubility in the water, blues are then classified into two
categories as follows:
(i)
Insoluble blues ------ Do not form clear solution in the water and the examples are
the Ultramarine blue and Prussian blue.
(ii)
Soluble blues ------- When dissolved in the water, it forms the clear solution. The
best examples of it are coal-tar dyes, methyl violet and then methylene blue.
ULTRAMARINE BLUES :
This is the most commonly used laundry blue and was a original mineral substance . It can be safely
used on the fabrics and do not have any harmful effect. It is mainly manufactured from the soda ash,