Senior Project
On
Study of various types of Softener (character, pH,
application process) in Finishing on cotton Knitted goods.
Supervising teacher
Ismat zerin
LecturerDepartment of Textile Engineering
Prepared by
Mihir Ranjon Das
ID# 05310054 Program: BSTEBatch: 1st
Semester: fall, 2009
Submission date: January 26, 2010
City University
40, Bulu Ocean TOWER, Kemal Ataturk Avenue,
Banani, Dhaka-1213.
By means of practical knowledge it’s not possible to apply the theoretical knowledge in the practical field. For any technical education, practical experience is almost equaled important in association with the theoretical knowledge. Now I wish to take this excellent opportunity to thank a lot of people who have assisted and inspired me in the completion of my training period.
Miss Ismat Zerin, my supervisor, to whom I am extremely indebted for his tremendous support and guidance throughout my training period. Being working with him I have not only earned valuable knowledge but was also inspired by his innovativeness which helped enrich my experience to a greater extent. His ideas and way of working was truly remarkable.
I also express my gratitude to Prof. Dr Md. Saiful Islam, Head, Department of Textile Engineering, for his support and continuous guidance throughout my long journey in City
University and the industrial training.
The industrial attachment is the process, which builds understanding, skills and attitude of the performer, which improves his knowledge in boosting productivity and services. University education provides us vast theoretical knowledge as well as more practical attachment, in despite of all these industrial attachment helps us to be familiar with technical support of modern machinery, skillness about various processing stages.
It also provides us sufficient practical knowledge about production management, work study, efficiency, industrial management, purchasing, utility and maintenance of machinery and their operation techniques etc. the above mentioned cannot be achieved successfully by means of theoretical knowledge only. This is why it should be accomplished with practical knowledge in which it is based on. Industrial attachment makes us reliable to be accustomed with the industrial atmosphere and improve courage and inspiration to take self responsibility.
Textile education can’t be completed without industrial training. Because this industrial training minimizes the gap between theoretical and practical knowledge and make us accustomed to industrial environment.
Table of Contents
Topics Page number Chapter1 1.0 General consideration……… 1 1.1 History………. 2 Chapter2 2.0 Raw Materials………. 3 2.0.1 Conditioning agents………. 3 2.0.2 Emulsifiers……… 3‐4 2.0.3 Other ingredients………... 4 2.1 Manufacturing Process………... 4‐5 2.2 Quality control……… 5 2.3 Future Softener………... 5‐6 2.4 Composition……… 6‐7 2.5 Reason for using softener………. 7 2.6 Desirable properties of Textile softener………. 7 2.7 Mechanism of Textile softener………... 7‐9 2.8 Fabric Softener……… 9 2.9 Classification Softener……… 9 Chapter3 3.0 Cationic Softener……… 10 3.0.1 Chemistry of Cationic Softener………... 10‐11 3.0.2 Mode of action………. 12 3.0.3 How to use………. 12 3.0.4 Properties of cationic softener……….. 12‐13 3.0.5 Advantages……… 13 3.0.6 Disadvantages………. 133.0.8.0 Quaternary Ammonium Salt………... 16‐19 3.0.8.1 Imidazolines………. 19‐20 3.0.8.2 N‐dimethyl ammonium chloride……….. 20‐23 3.0.8.3 N‐ distearyl‐N………... 23 3.0.9 TRADE NAMES OF CATIONIC SOFTENING AGENT ………. 23 Chapter4 4.0 AN‐IONIC SOFTENER……….. 24 3.2 TRADE NAME OF ANIONIC SOFTENING AGENTS………. 25 Chapter5 26 5.0 Silicone softeners………... 26 5.1 Properties………... 27 5.2 Silicone emulsion is two types………... 27 5.2.1 Micro emulsion……….. 27 5.2.2 Macro emulsion………... 27 5.3 Different Types of Softener………. 27‐28 5.3.1 Polydimethyl Silicon……… 29‐30 5.3.2 Polydimethyl siloxane……… 30‐31 5.3.3 Non‐ionic Silicon Softener……… 32‐33 5.3.4 Nonionic polysiloxane with amino groups……… 33‐34 5.3.5 Microemulsion with amino groups……….………... 34‐35 5.3.6 Aminofunctional polysiloxane………... 36‐37 5.3.7 Elastomer Silicones……….. 37 5.3.8 Synthosilky……… 37 5.3.9 Other Silicon Softener………. 37 Chapter6 6.0 Non‐ionic softeners... 38‐39
6.1 Chemistry of non‐ionic softeners……… 39‐41 6.2 How to use………. 41 6.3 Advantages……… 41 6.4 Disadvantage……… 42 6.5 Different Types of Non –ionic Softener……… 42 6.5.0 Polyethylene………. 42‐44 6.5.1 Ethoxylated Fatty Acid………... 44‐45 6.5.2 Silky Top………. 46‐47 6.6 TRADE NAMES OF NON‐IONIC SOFTENING AGENT………... 48 Chapter7 7.0 Amphoteric Softener………... 49 7.1 Hydrophilic Softeners………. 50 7.1.0 Special Features………. 50 7.1.1 Properties………... 50 7.1.2 Application……… 51 7.1.3 Padding Process………. 51 7.1.4 Storage & Handling Precautions………...………... 51 7.2 Urethane Softeners………... 51 7.2.0 Advantages……… 51‐52 7.2.1 Properties………... 52 7.2.2 Stability……… 52 7.2.3 Compatibility……… 52 7.2.4 Application Methods……… 53 7.2.5 Storage & Handling Precautions……….. 53 7.3.0 Function……….. 53‐54 7.3.1 Features……….. 54 7.3.2 Properties………... 54 7.3.3 Compatibility……… 54
7.3.6 Storage & Handling Precautions………... 55 7.4 MACRO SOFTENER………. 56 7.4.0 Special Features………. 56 7.4.1 Product Properties………... 56 7.4.2 Method of Usage………. 57 7.5 Micro softener………... 57 7.5.1 Special Features………. 57 7.5.2 Product Properties………... 57 7.5.3 Method of Usage……… 58 7.5.4 SS‐SOF 80 EXL………. 58
Study of various types of Softener (character, pH,
application process) in Finishing on cotton Knitted goods.
CHAPTER‐1
Study of various types of softener (Character, pH, Application
Process) in finishing on Cotton Knitted Goods.
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 1
1.0 GENERAL CONSIDERATION
Softening agents are applied to textiles to improve their hand, drape, cutting and sewing qualities. An effective softener must be readily dispersible in rinse water and rapidly absorbed so that uniform deposition on the fabric can occur within a relatively short treatment time and generally, exhaustion should take place in about 5min for the softener to be effective and economically usable. It must impart softness, fluffiness and lubricity to the treated cloth and reduce static build‐up, especially in the case of hydrophobic fibers like cellulose acetate, nylon, polyester and acrylic fibers. These effects should be obtained without the loss of fabric whiteness or brightness, and then the treated fabric should retain its ability to absorb in subsequent use for drying the body (bath towels) or other surfaces.
Fabric softener (also called fabric conditioner) is used to prevent static cling and make
fabric softer. It is available as a liquid or as dryer sheets. Popular brand names include Downy (Lenor), Snuggle, Bounce, Comfort and Sta‐Soft.
Most modern washing machines have a dispenser which can add liquid fabric softener to the load of laundry automatically on the final rinse; in launderettes one may need to add it manually. Some brands of washing powder have fabric conditioning built‐in which is claimed to save money when compared to buying ordinary washing powder and fabric softener separately. Some fabric softeners are also claimed to make ironing easier or to make clothes dry faster. For best results, un‐diluted liquid fabric softener should not be poured directly onto clothes.
Fabric softeners may also come in the form of dryer sheets, which are added to clothing in the tumble dryer to soften the fabrics and prevent static. Many alternative uses of dryer sheets have been suggested by users.
Fabric softeners work by coating the surface of the cloth fibers with a thin layer of chemicals; these chemicals have lubricant properties and are electrically conductive, thus making the fibers feel smoother and preventing buildup of static electricity. Other functions are improvements of iron glide during ironing, increased resistance to stains, and reduction of wrinkling.
Cationic softeners bind by electrostatic attraction to the negatively charged groups on the surface of the fibers and neutralizing their charge; the long aliphatic chains are then oriented towards the outside of the fiber, imparting lubricity. Vinegar works on some materials in a similar way, as the hydrogen ions bind to the anionic groups on the fibers. The disadvantage of coating fibers by hydrophobic layer is in decreasing the water absorption properties of the fabric, which may be undesirable in towels and diapers. Therefore the cationic softeners are often combined with other chemicals with lower affinity to the fibers. The use of fabric softener is contraindicated in some articles, such as microfiber textiles. Most good quality all‐cotton towels do not need to be treated with fabric softener and with repeated washings and dryings, they become softer naturally. Over time, towels that have softened with fabric softener are less absorbent.
1.1 HISTORY
A fabric softener is a liquid composition added to washing machines during the rinse cycle to make clothes feel better to the touch. These products work by depositing lubricating chemicals on the fabric that make it feel softer, reduce static cling, and impart a fresh fragrance. The first fabric softeners were developed by the textile industry during the early twentieth century. At that time the process that was used to dye cotton fibers left them feeling harsh. In the early 1900s, preparations known as cotton softeners were developed to improve the feel of these fibers after dyeing. A typical cotton softener consisted of seven parts water, three parts soap, and one part olive, corn, or tallow oil. With advances in organic chemistry, new compounds were created that could soften fabric more effectively. These improved formulations soon found their way into the commercial market.
By the 1960s several major marketers, including Procter and Gamble, had begun selling liquid fabric softener compositions for home use. The popularity of these products dramatically increased over the next decade as manufacturers developed new formulations that provided improved softness and more appealing fragrances.
Despite their growing popularity, fabric softeners suffered from one major disadvantage: the softener chemicals are not compatible with detergents and therefore they cannot be added to the washer until all the detergent has been removed in the rinse cycle. Initially, this restriction required the consumer to make an extra trip to the washing machine if they wanted to soften their clothes. In the late 1970s manufacturers found a way to deliver fabric softening benefits in a dryer sheet format. These sheets provide some of the benefits of fabric softeners but give the added convenience of being able to be added in the dryer instead of the washer rinse cycle. However, while dryer sheets are very popular today, liquid softeners are still widely used because they are more effective.
In the 1990s, environmentally minded manufacturers began test marketing ultra‐ concentrated formulations. These "ultra" formulations are designed such that only about one‐quarter as much product has to be used and therefore they can be packaged in smaller containers. However the perceived value to the consumer is lower because there are fewer products and the price is higher. It remains to be seen if these ultra concentrates will succeed in today's marketplace.
By the end of the 1990s, annual sales of liquid fabric softeners in the United States reached approximately $700 million (in supermarkets, drug stores, and mass merchandisers). For the sake of comparison, about $400 million worth of dryer sheets are sold each year. The major manufacturers such as Procter and Gamble (Downy) and Lever Brothers (Snuggle), dominate about 90% of the market share while private label brands account for the remaining 10%.
CHAPTER‐2
Study of various types of softener (Character, pH, Application
Process) in finishing on Cotton Knitted Goods.
2.0 RAW MATERIALS
2.0.1 Conditioning agents
Early fabric softener formulas were relatively simple dispersions of fatty materials that would deposit on the fabric fibers after washing. One of the most common ingredients used was dihydrogenated tallow dimethyl ammonium chloride (DHTDMAC), which belongs to a class of materials known as quaternary ammonium compounds, or quats. This kind of ingredient is useful because part of the molecule has a positive charge that attracts and binds it to negatively charged fabric fibers. This charge interaction also helps disperse the electrical forces that are responsible for static cling. The other part of the molecule is fatty in nature and it provides the slip and lubricity that makes the fabric feel soft.
While these quats do soften fabrics very effectively, they also can make them less absorbent. This is a problem for certain laundry items such as towels and diapers. To overcome this problem, modern formulations use quats in combination with other more effective ingredients. These newer compounds have somewhat lower substantivity to fabric which makes them less likely to interfere with water absorption.
One of the new classes of materials employed in fabric softener formulations today is polydimethylsiloxane (PDMS). Siloxane is a silicone based fluid that has the ability to lubricate fibers to give improved softening and ease of ironing. Other silicones used in softeners include amine‐functional silicones, amide‐functional silicones and silicone gums. These silicone derivatives are modified to be more substantive to fabric and can dramatically improve its feel.
2.0.2 Emulsifiers
The conditioning ingredients used in fabric softeners are not typically soluble in water because of their oily nature. Therefore, another type of chemical, known as an emulsifier, must be added to the formula to form a stable mixture. Without emulsifiers the softener liquid would separate into two phases, much like an oil and vinegar salad dressing does. There are three types of emulsifiers used in fabric softener formulations: micro‐emulsions, macro‐emulsions, and emulsion polymers. Macro‐emulsions are creamy dispersions of oil and water similar to hand lotions or hair conditioners. The emulsifier molecules surround the hydrophobic oil or silicone droplets and allow them to be dispersed in water. A micro‐ emulsion is chemically similar, but it creates oil particles that are so small that light will pass around them. Therefore, a micro‐emulsion is characterized by its clarity and transparency as opposed to being milky white. Furthermore, one of the advantages of micro‐emulsion is that the silicone particles are so tiny that they will actually penetrate into the fibers, while macro‐emulsions only deposit on the fiber's surface. The third type, emulsion polymers, creates dispersions that look similar to a macro‐emulsion. This system does not use true emulsifiers to suspend and dissolve the oil phase. Instead, emulsion polymers create a stabilized web of molecules that suspend the tiny silicone droplets like fish caught in a net. The emulsifying system used in softeners must be chosen carefully to ensure the
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 4
have no charge) and cationic emulsifiers (those that have a positive charge) are typically used. Anionic surfactants (which have a negative charge) are rarely used because the fabric conditioning agents have a positive charge which would tend to destabilize an anionic emulsion.
2.0.3 Other ingredients
In addition to conditioning agents and emulsifiers, fabric softeners contain other ingredients to improve their aesthetic appeal and to ensure the product will be shelf stable. For example, fragrance and color are added to make the product more pleasing to consumers. In addition, emulsion stabilizers and preservatives are used to ensure the product quality.
2.1 MANUFACTURING PROCESS
The preferred method for manufacturing liquid softeners involves heating the ingredients together in one large mixing vessel. Mixing tanks should be constructed from high grade stainless steel to prevent attack from the corrosive agents in the formula. The tank is typically equipped with a jacketed shell that allows steam and cold water to be circulated, so the temperature of the batch can be easily controlled. In addition the tank is fitted with a propeller type mixer that is driven by a large electric motor. This kind of mixing blade provides the high shear that is needed to properly disperse the ingredients.
The first step in the manufacturing process is to fill the tank with the specified amount of water. Water is added first because it acts as a carrier for all the other ingredients. Deionized water is used because it is free from metal ions that can affect the performance of the batch. Conventional formulations can contain as much as 80‐90% water.
Once the water has been added to the tank, heating and mixing is initiated. When the water has reached the appropriate temperature, the emulsifiers are added. Since these chemicals tend to be waxy solid materials they are added at relatively high temperatures (between 158‐176TF [70‐80°C]). While the order of addition depends on the specific formula, it usually more effective to disperse the emulsifiers prior to adding the less water‐soluble materials. Emulsifiers are used between 1‐10%, depending on the specific chemicals that are selected.
The conditioning ingredients used in softeners are not typically water soluble, so they are added to the water phase after the emulsifiers. For a typical strength formulation about 5% is used. For more concentrated formulations, levels of 10% are more common. When blends of quats and silicones are used, the silicones are used at levels as low as 0.5‐1.5%.
When pre‐emulsified silicones are used in the formula they are added late in the process when the temperature is lower and there is less mechanical agitation in the batch. If higher molecular weight silicones are used that have not been pre‐emulsified they must be added to the batch at high temperatures with a high level of agitation to ensure the silicone oil droplets are evenly dispersed.
Heating and mixing continues until the batch is homogeneous. At this point cool water is circulated around the tank to lower the temperature. As the batch cools, the remaining ingredients, such as preservatives, dyes, and fragrance, are added. These ingredients are used at much lower concentrations, typically below no more than a few percent for
fragrance and less than 1% for preservatives and dyes. When the batch is complete, a sample is sent to the analytical chemistry lab to ensure it meets quality control standards for solids, pH, and viscosity. The completed batch may be pumped to a filling line or stored in tanks until it is ready to be filled.
When the product is ready to be filled into the package, it is transferred to an automated filling line. Plastic bottles are fed onto a conveyor belt that carries them under a filling nozzle. At the filling head there is a large hopper that holds the formulation and discharges a controlled amount, usually set by volume, into the bottle. The filled package continues down the conveyor line to a capping machine that applies the closure and tightens it. Finally, the filled bottles are packed in cartons and stacked pallets for shipping.
2.2 QUALITY CONTROL
The finished fabric softer formulations are tested using a number of different protocols. Simple laboratory tests are used to determine basic properties such as pH, viscosity, and percent solids. These tests can help confirm that the correct ingredients were added at the appropriate levels.
Other, more rigorous, tests are done to ensure the formulation is functioning correctly. One such evaluation is a water absorbency test, sometimes called the Drayes Wetting Test. This procedure involves dropping small pieces of treated fabric onto water and recording the length of time required for the fabric to sink. This measurement is taken 10 times to obtain an average result. Anti‐wrinkle properties can be evaluated by asking panelists to rate samples of fabric before they have been ironed. They are asked to numerically rate the amount of wrinkling between the test sample and the fabric softener treated sample. The test to measure ease of ironing is also done using trained panelists.
These tests are performed on swatches of identical fabrics with the only difference being that one fabric has been treated with softener and the other has been washed in detergent only. 100% cotton pillowcases are used for wrinkling and ironing tests while 100% cotton terry towels are used for evaluating softness and water absorbency. The swatches are dried in a controlled environment at 71.6°F (22°C) and 65% relative humidity for 24 hours before testing. 2.3 FUTURE OF SOFTENER There are two formula related areas that will affect the future of fabric softeners. The first is the impact the ultra‐concentrates will have on the market. At the time of this writing it is too soon to tell if they will be accepted by consumers. The second area is related to the role that multi‐functionality will play in the future. As chemists develop new more efficacious ingredients there is more potential for additional consumer‐perceivable benefits. At the turn of the millennium, multifunctional fabric softener formulations are the latest trend. These new products not only soften clothes but also improve the ease of ironing, reduce wrinkling in the dryer, and provide stain protection. Both Lever Brothers and Procter and Gamble have capitalized on this trend with new formulations that deliver multiple fabric care benefits. Finally, manufacturers may turn to new delivery forms to make softeners easier to
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 6
use. One new method introduced by P&G in the late 1990s is the "Downy Ball." This is a reusable plastic tennis ball sized sphere that is filled with liquid Downy and added to the washer at the beginning of the cycle. The ball stays sealed during washing but the spinning of the rinse cycle triggers it to open and release the softener. For consumer who does not have an automatic softener dispenser on their washing machines, the "Downy Ball" saves them from the trouble of adding the liquid in a separate step. Other innovative dispensing devices like this may become more common as manufacturers strive to differentiate their products from the competition.
2.4 COMPOSITION
The earliest fabric softeners were developed during early 20th century to counteract the harsh feel which the drying methods imparted to cotton. The cotton softeners were typically based on water emulsion of soap and olive oil, corn oil, or tallow oil.
Contemporary fabric softeners tend to be based on quaternary ammonium salts with one or two long alkyl chains, a typical compound being dipalmitoylethyl hydroxyethylmonium methosulfate. Other cationic compounds can be derived from imidazolium, substituted amine salts, or quaternary alkoxy ammonium salts. One of the most common compounds of the early formulations was dihydrogenated tallow dimethyl ammonium chloride (DHTDMAC).
Anionic softeners and antistatic agents can be, for example, salts of monoesters and diesters of phosphoric acid and the fatty alcohols. These are often used together with the conventional cationic softeners. Cationic softeners are incompatible with anionic surfactants presenting the bulk of surfactants used in detergents, with which they form inefficient precipitate; therefore they cannot be mixed with the detergent, but have to be added during the rinse cycle instead. Anionic softeners can be combined with anionic surfactants directly. Other anionic softeners can be based on smectite clays. Some compounds, such as ethoxylated phosphate esters, have properties of softening, anti‐static, and surfactant. The softening compounds differ in affinity to different materials. Some are better for cellulose‐based fibers; others have higher affinity to hydrophobic materials like nylon, polyethylene terephthalate, polyacrylonitrile, etc.
Silicone based compounds such as polydimethylsiloxane comprise the new softeners which work by lubricating the fibers. Silicone derivatives are used as well. Modified to contain amine or amide groups; they bind better to the fabrics and have much improved feel. They have essentially the same role as oils had in the early formulations.
As the softeners themselves are often of hydrophobic nature, they are commonly occurring in the form of an emulsion. In the early formulations, soaps were used as emulsifiers. The emulsions are usually opaque, milky fluids. However there are also micro emulsions where the droplets of the hydrophobic phase are substantially smaller. The advantage of micro emulsions is in the increased ability of the smaller particles to penetrate into the fibers. A mixture of cationic and non‐ionic surfactants is often used as an emulsifier. Another approach is using a polymeric network, an emulsion polymer.
Other compounds are included to provide additional functions; acids or bases for maintaining the optimal pH for adsorption to the fabric, electrolytes, carriers (usually water, sometimes water‐alcohol mixture), and others, e.g. Silicone‐based anti‐foaming agents, emulsion stabilizers, fragrances, and colors. Relatively recent forms on the market are the
ultra‐concentrates, where the amount of carriers and some other chemicals is substantially lower and much smaller volumes are used. In recent years, the importance of delivering perfume onto the clothes has possibly exceeded that of softening. The perfume levels in fabric softeners has gradually increased, requiring high shear mixing technology to be used to incorporate greater amounts of perfumes within the emulsions. Long term release of perfume on the fabric is a key technology now being utilized. Each country tends to have different perfume requirements and brands may have different softener/perfume ratio depending on the count. 2.5 REASONS FOR USING SOFTENER • As the textile material goes under various mechanical and chemical processes that make the surface of the material harsh. For example, Removal of natural oil and waxes by scouring and bleaching. • Resin finishing of textile material also imparts some degree of harshness. Soaping of textile material also add harsh feeling to the material. • As consumers are much more caring about the touch of textile material. This is also reason for using softener. 2.6 DESIRABLE PROPERTIES OF TEXTILE SOFTENER • It should be easy to handle. • It should have good compatibility to other chemicals. • It should not affect the shade of the material. • It should not affect the fastness of dyed material. • It should not cause any yellowing effect on dyed and finished material. • It should be stable to high temperature. • It should be non volatile by water vapor. • It should be non toxic and non caustic. • It should be easily bio degradable. 2.7 MECHANISMS OF SOFTENING EFFECT Softeners provide their main effects on the surface of the fabrics. Small softener molecules, in addition, penetrate the fiber and provide an internal plasticization of the fiber forming polymer by reducing of the glass transition temperature. The physical arrangement of the usual softener molecules on the fiber surface is important and shown in Fig.‐1.
Depending on the ionic nature of the softener molecule and the relative hydrophobicity of the fiber surface, cationic softeners orient themselves with their positively charged ends toward the partially negatively charged fabrics (zeta potential), creating a new surface of
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 8 hydrophobic carbon chain that provide the characteristic excellent softening and lubricity seen with cationic softeners. Anionic softeners, on the other hand, orient themselves with their negatively charged ends repelled away from the negatively charged fiber surface. This leads to higher hydrophilicity, but less softening than with cationic softeners.
The orientation of non‐ionic softeners depends on the nature of the fiber surface, with the hydrophilic portion of the softener being attracted to hydrophilic surfaces and the hydrophobic portion being attracted to hydrophobic surface.
Fig. 1 Schematic orientation of softeners on fiber surface
(a) Cationic softener (b) Anionic Softener at fiber surface Non‐ionic softener at (c) Hydrophobic (d) Hydrophilic fiber surface. 2.8 FABRIC SOFTENER • Fabric softeners work by coating the surface of the cloth with a thin layer of chemicals. • So the term softener can be defined as an auxiliary applied to textile material in order to improve its handle with mo0re pleasing touch. 2.9 CLASSIFICATION OF SOFTENER Based on the ionic natures softener can be classified into six categories: 1. Cationic softeners 2. Anionic softeners 3. Non ionic softeners 4. Amphoteric softeners 5. Reactive softeners 6. Silicone softeners 7. Antiozone Softener 8. Urethane Softeners 9. Macro softener 10. Micro softener
CHAPTER‐3
Study of various types of softener (Character, pH, Application
Process) in finishing on Cotton Knitted Goods.
3.0 CATIONIC SOFTENERS
Cationic softeners have been defined as material which dissolved or disperse in water, concentrate and orient at interfaces and ionize in such a way that the cation includes a hydrocarbon chain, which is hydrophobic and contains from 8 to 25 carbon atoms.
3.0.1 Chemistry of cationic softeners
The simplest cationic are the primary, secondary and tertiary mono‐amines and their salts, formed by neutralization of the amines, usually with acetic acid. The primary and secondary amines have little importance in the textile field, since the free hydrogen on the nitrogen atom leads to fabric, yellowing. But, they serve as raw materials for making quaternary aminonium compounds. Reaction, with alkylating like methyl chloride, benzyl chloride, dimethyl sulphate, etc converts the insoluble amines into water soluble salts, which are more active than the original amines. These quaternary compounds have excellent thermal stability, especially on the acidic site. Stearyl or distearyl dimethyl ammonium chloride or methosulphate, cetyl dimethyl benzyl ammonium chloride or methosulphate, etc belong to this group.
The next groups of commercial importance are amido‐amines, which are formed by the reaction of a fatty acid or a glyceride (fat) and a substituted or unsubstitued short‐chain polyamine. Generally, the reaction occurs at only one of the amine functions, giving an amide leaving one or more unreacted amino functional groups. The amine may be diethylene tri‐amine, N. N‐diethyl ethylene, etc. Derivatives of ethylene diamine have high melting points and exhibit poor solubility. This amide is quaternised either with glacial acetic acid or hydrochloric acid to give cationic fabric softeners. They are good, especially for chlorinated wool, which is quite harsh. All the members of this group are quite stable to hydrolysis. Imidazolines are the next group of cationic softeners. These are formed from fatty acids and polyethylene polyamine. COOH R +H2N CH3 CH 2 NH CH2 CH2 NH2 R CO NH CH2 CH2 NH CH2 CH2 NH -H2O -H2O(Heating) CH3 CH2 N C R N CH3 CH2 NH2
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 11
The cyclic compound (imidazoline) has a lower melting point and higher solubility than the parent amidoamine. These cyclic products may subsequently be acetylated, neutralized or reacted with ethylene oxide. A fourth group of cationic includes aminoesters, prepared by reaction of fatty acid or acid chloride with amino alcohols like diethanolamine or hydroxyethyl ethylene diamine. COOH R + NH CH2 CH2 OH NH H2C CH3 OH HOCH2 CH2 NH CH2 R COOCH2 CH2 CH2 NH CH2 CH2 R COOHHO CH2 NH 2 NH CH2 CH2 R COO CH2 CH2 NH2
These are quite water soluble, give good softening properties and are easy to make, but being esters, have a definite disadvantage of being easily hydrolyzed. After quaternisation also, the ease of hydrolysis is retained by them.
Cationic softener belonging to the fifth group may be prepared from dicyandiamide and stearyl amine followed by reaction with ethylene oxide and quqternisation. The treatment with ethylene oxide to obtain the adduct is done to impart water solubility to the compound. 2 H2N C N H2N C NH C NH N C18H37 NH 2 H2N C NH C NH ( S t e a n y l a m i n e ) C18H37 NH C NH C NH 2 NH NH ( S t e a n y l d i g u a n id e ) CH 2 O CH 2 C18H37 NH C NH C NH CH 2 CH 2 OH NH 3 NH CH 3--COOH C18H37 NH C NH C NH 2+ CH 2 CH 2 OH NH NH HOOC CH 3
3.0.2 Mode of action
When a quaternary ammonium softener is dissolved in water, it ionizes into a hydrophilic head with a negative charge and a hydrophobic tail carrying a positive charge. On the other hand, when textile fibers are entered into water they acquire a negative charge. When a textile fiber is entered into an aqueous solution of a cationic softener.
During the softening treatment the negative charge on the fiber surface attracts the positive tail of the cationic softener. This result in firmly anchoring of the softener residue on the fiber substance, somewhat similar to sheathing the fiber with an oily film. This is responsible for obtaining a soft handle and a pliable, well lubricated fiber surface. 3.0.3 How to use Cationic softeners are available in the form of off‐white pastes with a slightly acidic reaction and can be dilute with water to any extent. Further addition of an acid is not necessary to affect dissolution/dilution. Being cat ion‐active they should not be mixed with anion‐active products like soaps, Turkey red oil, alkyl benzene sulphonates, fatty alcohol sulphates, etc. If hard water is used for their dilution, they do not react with calcium and magnesium salts. However, they are sensitive to calcium carbonate, which neutralizes the small amount of the acid which is present in the softener and which is necessary for the dissolution of the softener. Therefore if hard water is used, a small amount of acetic acid should be added to neutralize the alkalinity. The pH of the treating bath should be about 4 to overcome the difficulties arising out of alkalinity of the water used for diluting the softener.
The softener may be applied by the padding or the exhaustion method. In thy latter, 0.25% to 2% softener on the weight of the material may be used and enough time given for adequate exhaustion. The cationic softeners find the following applications: • As a self‐finish on peace goods to impart a lofty, full softness. • As a softener for yarn • As a softener to modify the handle of resin‐treated fabrics • As an static agent for loose fibers 3.0.4 Properties of cationic softener • They are compatible with most resin finishes. • It has tendency to change the shade. • It also affects the fastness of certain dyestuffs. • It also causes discoloration on white fabrics.
• As cationic softeners have positive charge they are affected to cotton or synthetic fabric.
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 13
• Nitrogen containing substances like quaternary fatty acid esters, dimethyl distearyl compounds are used in making cationic softeners.
3.0.5 Advantages
Substantivity of cationic softeners to textile fibres involves complete exhaustion from application baths as well as firm bonding of the softener to the fabric. High degree of softener is one of the advantages of cationic softeners.
Cationic impart other useful textile properties. For example, they improve the fibre tear strength due to increased internal lubrication which reduces the effect of abrasion. Better sewability and reduced needle cutting are the effect of softener treatment. In these cases, lubrication allows high speed needle to push the fibre aside without cutting the thread. For example, on a particular wool/nylon shirt, at 4,500 stitches/min, only one or two yards could be sewn; when the softener is applied to the fabric, a minimum of 52 yards can be sewn.
3.0.6 Disadvantages
Lack of general compatibility with certain textile processing chemicals is the foremost disadvantages of cationic. Thus anionic detergents & soap react with cationic softener & form precipitates, giving an insoluble, unionized complex.
COO
-Na
+R
+ [R'N(CH
3)
3]
+Cl
-COO
-R
[R'N(CH
3)
3]
++ Na
+Cl
-This precipitation reaction eliminates their use in anionic detergent processing solutions and on insufficiently washed fabrics pre‐treated with anionic detergent. When the precipitation takes place the softening property is reduced. This precipitation makes it necessary to incorporate cationic softeners as after‐rinses for fabrics. There is a yellowing effect, particularly on ageing of bleached cotton fabrics. However, this may be minimized by a proper choice of the softener.
3.0.7 Application
There are two principle methods of application of cationic softeners‐ 1) exhaustion from dilute baths, 2) padding from relatively concentrated solution.
The long‐bath (exhaustion) process is especially suitable because of the natural substantivity of the softeners and is usually adopted for knitted goods, not requiring resin treatment. With thermosetting resins (urea‐formaldehyde resin) cationic lubricants softeners are a valuable adjunct to the treatment: since they are not appreciably removed in the subsequent washing operation and serve to reduce needle cutting during garment manufacture and generally impart improved tear and abrasion resistance.
3.0.8 Various types of cationic softener and their character, pH, application process 3.0.8.0 Quaternary Ammonium Salt
Quaternary Ammonium Salt is a weak cationic softening agent with anti‐static effect. It is recommended for synthetics like polyester, acrylic, acetate, nylon and their blends. It is excellent for laundry washing fastness The advantages of Quaternary Ammonium Salt are • It is pump able, pour able, low viscosity softener in emulsion form • Can be applied in both exhaust and padding processes • It is compatible with silicone and non‐ionic products used in finishing formulation • Improves the lubricancy of the fibers and facilitates further processing of the goods • Imparts a very soft, smooth handle to the goods • It imparts good touch and elasticity like wool for acrylic and its blend • It has no influence on dyeing fastness • It poses no yellowing problem to white goods. Properties Appearance Milky liquid Composition Polyamide derivative Ionicity Weak cationic pH (1% solution) 5.0 ± 0.5 Solubility Soluble in water in any proportion Application pH range 4 ‐ 7 Application temperature range 60°‐70C° Stability in Hard water Good Acids Good Alkali Good
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 15 Compatibility with Non‐ionic surfactant Generally very good Anionic surfactant Not compatible Silicone softener Good Optical brightener Not good Application Methods Quaternary Ammonium Salt can be applied by exhaust as well as by padding method: a) Exhaust application Quaternary Ammonium Salt 0.5 ‐ 2% M:LR ratio 1:10 Temperature 45° ‐ 50°C pH 4 ‐ 5 Time 20 ‐ 30 min. (B) Application on Knit fabric Quaternary Ammonium Salt 1 ‐ 2% M:LR Ratio 1:10 Temperature 45°‐50°C pH 4 ‐ 5 Time 20 ‐ 30 min. (C) Softening of garment (Washwheel) Quaternary Ammonium Salt 0.5 ‐ 2% Temperature 45° ‐ 50°C pH 4‐5 Time 20 ‐ 30 min.
(D)Padding Application Quaternary Ammonium Salt 20 ‐ 30 g/l pH 4 ‐ 5 Storage & handling precautions • Store in cool place • Avoid storing in direct sunlight. • Quaternary Ammonium Salt should be stored at ambient temperatures. • The shelf life of Quaternary Ammonium Salt is one year. • The usual precaution in keeping chemicals away from eyes and skin should be observe 3.0.8.1 Imidazolines Imidazolines is a cold water soluble cationic softener and hence, it is excellently suitable for cotton, t/c knitted blend fabrics. It is also suitable for resin processing industry. It imparts very good hand feeling and antistatic properties. Because of its low‐yellowing specific characteristic, it is very well suited for blue and white jeans laundry or stone‐washing. Advantages • Readily soluble in cold water • No problem of yellowing on heating • On synthetics, it provides silk‐like handle • It does not alter dye fastness • Non‐irritant on human skin • Well suited for cheese dyeing process. Properties Appearance Milky white paste Ionicity Cationic pH (2% solution) 4.5 ± 1 Chemical nature Polyamine derivatives Solubility Soluble in cold water Solid content 28%
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 17 Stability Hard water Good Acids Good Alkalis Good Compatibility with Non‐ionic surfactant Generally very good Anionic surfactant Not compatible Silicone softener Good Optical brightener Not good Application Methods Imidazolines can be applied by exhaust as well as by padding method. Exhaust method (a) Post conditioning of acrylic yarn especially in the final rinse of yarn dyeing m/c: Imidazolines 0.5 ‐ 2% (owf) M:L Ration 1:10 Temperature 45° ‐ 50°C pH 4 ‐ 5 Time 20 ‐ 30 min (b) Application on Knitted fabric: Imidazolines 1‐2% (owf) M:L Ration 1:10 Temperature 45° ‐ 50°C pH 4 ‐ 5 Time 20 ‐ 30 min
(c) Softening of garment (Washwheel): Imidazolines 1 ‐ 2% (owg) M:L Ration 1:10 Temperature 45° ‐ 50°C pH 4 ‐ 5 Time 20 ‐ 30 min Padding method Imidazolines 20 ‐ 30 g/l pH 4 ‐ 5 Storage & Handling Precautions • Store in cool place • Avoid storing in direct sunlight • The shelf life of Imidazolines is one year if stored properly • The usual storage, handling, usage and safety precautions should be observed 3.0.8.2 Ndimethyl ammonium chloride
N‐dimethyl ammonium chloride Flake is an excellent cationic softener, cold water rapid soluble for cotton, terry cotton knitted blend fabrics, and for resin processing industry. It has a very good hand feeling and antistatic properties. Because of its low‐yellowing specific characteristic, it is very suitable for blue and white jeans laundry or stone‐washing processing. Characteristics Appearance Light yellowing white flake Ionic Cationic pH 2% solution 4.5 ± 1 Content Polyamine derivatives Solubility Soluble in cold water
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 19 Advantages • In case it is used for synthetics provides silk‐like handling. • Ndimethyl ammonium chloride Flakes treated febric garments dose not get yellowing. • Almost no influence on dyes fastness. • It can be rapidly soluble in cold water; its solution is very soluble. • Non‐irritant on human skin. • It is very suitable for cheese dyeing process. Application • Put 10kg Ndimethyl ammonium chloride Flakes into water at more than 25°C about 30 ‐ 60 min and mix until it's completely dissolved. • After completely dissolved, please filter it before packed. • Using quantity suggestion: based on 10% solution 1.5% (owf) 3.0.8.3 N distearylN [[ N‐ distearyl‐N Flakes is a warm water soluble cationic softener and hence, it is excellently suitable for cotton, terry cotton knitted blend fabrics. It is also suitable for resin processing industry. It imparts very good hand feeling and antistatic properties. Because of its low‐ yellowing specific characteristic, it is very well suited for blue and white jeans laundry or stone‐washing. Advantages • Readily soluble in warm water • No problem of yellowing on heating • On synthetics, it provides silk‐like handle • It does not alter dye fastness • Non‐irritant on human skin • Well suited for cheese dyeing process
Properties Appearance Solid light yellow flakes Ionicity Cationic pH (2% sol) 4.8 Chemical nature Fatty acid amide Solubility in water Readily soluble in warm water Guideline For making Catasoft solution using N distearylN Flakes • Add 10 kg of N distearylN Flakes into 100 litre of water for 10% active content. The addition should be carried out at above 60°‐70° C for 30‐60 min with constant stirring for a complete dissolution. • After complete dissolution is ensured, please filter it before packing. • Recommended dosage from the 10% N distearylN Flakes solution is 1.5% on the weight of fibre (owf) Storage & Handling Precautions • Store in cool place • Avoid storing in direct sunlight • The usual precautions in keeping chemicals away from eyes and skin should be observed 3.0.8.4 Concentrated cationic softener [[ Concentrated cationic softener is a cationic softener which is not diluted from the flakes or cake but formulated to achieve limpy and elastomeric finish. It can be used for cotton, polyester/cotton fabrics. It has a very good hand feeling and anti‐static properties. Because of its low‐yellowing specific character, it is very suitable for garment processing of blue and white jeans. Advantages • It is pump able, pourable, low viscosity softener in emulsion form Can be applied in both exhaust and padding processes
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 21
• It is compatible with silicone and cationic products used in finishing formulation • It has no influence on dyeing fastness. • Does not yellow when treated fibers are heated • Does not influence dye fastness • Does not irritate human skin. • Suitable for cheese dyeing process. • Keep fabric low‐ yellowing, • Provides bulky and heavy feel • Neutral pH Properties Appearance White paste Composition Ethylene oxide condense product Ionicity Cationic pH (1% solution) 7 ± 1 Solubility Soluble in water in any proportion pH 5 ‐ 8 Stability Hard water Good Acids Good Alkalies Good Compatibility Non‐ionic surfactant Good Anionic surfactant Good Silicone softener Good Optical brightener Good
Application Methods Concentrated cationic softener can be applied by exhaust as well as padding method: Exhaust application (A) Post softening of yarn especially in the final rinse of yarn dyeing m/c: Concentrated cationic softener 0.5 ‐ 2% (owy) M:L ratio 1:10 Temperature 45° ‐ 50°C pH 5 ‐ 8 Time 20 ‐ 30 min (B)Application on knitted Concentrated cationic softener 1 ‐ 2% (owf) M:L R 1 : 10 Temperature 45 ‐ 50°C pH 5 ‐ 8 Time 20‐30 min. (C) Softening of garment (Wash‐wheel) Concentrated cationic softener 0.5 ‐ 2% (owg) Temperature 45 ‐ 50°C pH 4 ‐ 8 Time 20 ‐ 30 min Padding application Concentrated cationic softener 20 ‐ 30 g/l pH 4 ‐ 5 Impregnate fabric at 70‐80% pick‐up, dry at 120° ‐ 140°C for 2‐3 min.
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 23 Storage & handling precautions • Store in cool place • Avoid storing in direct sunlight. • It should be stored at ambient temperatures. • The shelf life of concentrated cationic softener is one year. The usual precaution in keeping chemicals away from eyes and skin should be observed. 3.0.9 TRADE NAMES OF CATIONIC SOFTENING AGENT Name of the Product Name of the Company Auxisoftener K Auxuchem Cirrasol CS ICI (indid) pvt. Ltd. Arkoline HCS Hico Products pvt. Ltd Katasoftener Ahura Chemical products pvt. Ltd. Ciranine HS Sandoz(india) ltd. Sarcamine GG/LG Gujchem Distillers India. Ltd Katafin Associated Chemicals Catafinish/HWN Chemox Industrial corpn. Chemosine HCS/TAF/LW Chemox Industrial corpn. Katon/SP The Mill Factors corpn. Cason S Indoken ltd Taffulon 320A DaiIchi Karkaria pvt. Ltd Softnol Laxmi Chemical copn. Katasol Kemicolor Indus. Supermine GG/HC Supertex (india) copn. Ashoka catosol Ashok Brothers Texamyn FS Britex Industry Finisoft M C.D. Corporation Diotex AC Diamond Chemical copn. Gehine KS Germochem Indus.
CHAPTER‐4
Study of various types of softener (Character, pH, Application
Process) in finishing on Cotton Knitted Goods.
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 24
4.0 ANIONIC SOFTENER
Anionic softening agents are available in the form of off‐white thick paste, creamish viscous paste, which can be diluted with hot water to gibe opalescent solutions. The hot solutions can be diluted with water any temperature to the required concentration. Being anionic in character, they are compatible with direct dyes, optical whitening agents, starches, glue, gelatine, gums, resins, polyvinyl alcohol, blueing agents, etc and are stable to hard water, dilute alkalies and dilute acids. They may be applied on cotton, viscose rayon, acetate rayon, silk and nylon yarns to produce soft and supple finishes.
Solutions of the anionic softening agents can be prepared by pouring 20 times its weight of boiling water with stirring and boiling for 5 to 10min. The solution may then be diluted with water at the required temperature with good stirring. In he actual application, the textile materials may be steeped in or padded with a solution of the anionic softening agent, followed by hydro‐extracting or squeezing to remove the excess liquor and finally drying without rinsing. The application may be carried out in a beck, winch, jigger, padding mangle or package dyeing machine.
The concentrations of the softeners to be used depend upon the degree of softness required and the nature of the yarn or fabric being treated. Generally, a concentration of 2 to 10 g/l of the softener is suitable.
The softener may be applied as a lubricant to cotton fabrics, which are subsequently subjected to the raising operation to get a dense and soft pile and the fabric gets a lofty handle. The number of operations may be reduced when the lubricant is present. Initial trials may be carried out by padding the cloth with a solution containing 10g/l of the softener at 50°c to 60°c followed by drying on a cylinder drying range or any other. Addition of 5g/l of glycerin to the pad‐bath is advantageous in dry climates. Anionic softening agent can be used as a processing agent for rayon filament yarn and staple fiber to impart a soft handle. During carding, drawing and spinning, it acts as a lubricant. It may be applied as aqueous dispersions containing 2 to 5g/l of the softener by spraying or circulating in a package dyeing machine at 45°c to 50c°
3.2 TRADE NAME OF ANIONIC SOFTENING AGENTS Name of the product Name of the company Auxisil XLHW Auxichem Ashoka anosol XL350 Ashok Brothers Arkoline/SSW Hico Products pvt. Ltd. Ceramine PA Sandoz(india) ltd Finish XLHW Ahura Chemical Products pvt. Ltd. Finotes SL Laxmi chemical Corpn. Lusil XLHW ICI(india) pvt. Ltd. Sarluxol XL Gujchem distillers(india) ltd shinol Kemicolor Industries Ambusil XL Shri Ambuja Chemicals co. Anionic finish Britex industries Kemox Softener XL Chemox pvt. Ltd Neofinish EXEL/XLH Chemox industrial copn. DiofinishXL Diamond Chemicals corpn Hinorgasil XL Hindustan Oraganic Products Lustrol XLHW Indokem ltd. Katon XL The Mill Factors copn. Argolyn SW Modern chemical corpn. Mycusil XL Mysore Chemical indus. Nitcocil XL New India Traiding Copn. Supersil XL Supertex India Corpn. Ultrafil XL Ultra Color Copn. Lusterool HW Shoorji Vallabhdas Colours
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 25
CHAPTER‐5
Study of various types of softener (Character, pH, Application
Process) in finishing on Cotton Knitted Goods.
5.0 Silicone softeners
None‐ionic and cationic examples of silicone softeners are shown in Fig.‐3.They provide very high softeners, special unique hand, high lubricity, good sewability, elastic resilience, crease recovery, abrasion resistance and tear strength. They show good temperature stability and durability, with high degree of permanence for those products that form cross linked films and a range of properties from hydrophobic tohydrophilic. Fig – 3. Chemical structures of typical silicone softeners. 5.1 Properties • A new class of anionic softeners. • Expensive • It gives improved wrinkle recovery also. • Initially polydimethyl siloxane(PDMS) was used as softener. • Later amino functional Silicone softener was developed which gives high lubricity with small proportions. • It is more expensive.
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 27
Remarks: Silicone softener is found in market at emulsion form 5.2 Silicone emulsion is two types • Micro emulsion • Macro emulsion 5.2.1 Micro emulsion • It is clear in appearance • It’s particle size is less than 40 nm • This emulsion gives inner softness as it penetrates into the fiber. 5.2.2 Macro emulsion • It is milky in appearance • It’s particle size is in the range between 150‐250 nm • It gives surface softness as it covers the fiber. 5.3 Different Types of Softener 5.3.1 Polydimethyl Silicon Polydimethyl Silicon is a highly concentrated silicone softener in gel form. It is made from premium quality of silicone which gives excellent softness and surface smoothness to garments and fabrics. It is highly exhaustible. Advantages • Imparts durable soft handle • Imparts superior smooth feel • Increases crease recovery • Increases shade depth and brilliancy when used on dyed fabric/garments
Properties Appearance Transparent liquid Composition Blend of amino silicones and urethane Ionicity Non‐ionic pH (1% solution) 7.0 ± 1.0 Solubility Soluble in water Application pH range 4.5‐5.5 Solid Content 42% Application Methods Polydimethyl Silicon can be applied by exhaust as well as by padding method. Exhaust method Polydimethyl Silicon 1‐4 % (owg) Temperature 45° ‐ 50°C pH 5 ‐ 5.5 Time 20 ‐ 30 min Padding method Polydimethyl Silicon 10‐40 g/l pH 5 ‐ 5.5 Storage & Handling Precautions • Store in cool place and avoid storing in direct sunlight • The shelf life of Polydimethyl Silicon is two years under recommended storage • The usual precautions in keeping chemicals away from eyes and skin should be observed
Study of various types of softener (Character, pH, Application Process) in Finishing on Cotton Knitted Goods Page 29 5.3.2 Polydimethyl siloxane Polydimethyl siloxane is a silicone softener in transparent gel form. It is made from premium quality of silicone which gives excellent surface softness and bulk to garments and fabrics with durable softness. It is highly exhaustible. Advantages • Imparts a bulky touch • Imparts smooth feel • Imparts crease recovery • Increases shade depth and brilliancy when used on dyed fabrics/garments Properties Appearance Transparent Liquid Composition Blend of amino silicones and urethane Solid content 80%
Inocity non – ionic pH (1% solution) 7.0 ± 1.0 Solubility Soluble in water in any proportion Application pH range 4.5‐5.5 Application Polydimethyl siloxane can be applied by exhaust as well as by padding method. Exhaust method Polydimethyl siloxane 1 ‐ 4 % (owg) Temperature 45° ‐ 50°C pH 5 ‐ 5.5 Time 20 ‐ 30 min
Padding method Polydimethyl siloxane 10‐40 g/l pH 5 ‐ 5.5 Storage & Handling Precautions • Store in cool place, avoid storing in direct sunlight • The shelf life of Polydimethyl siloxane is two years if stored properly • The usual precautions in keeping chemicals away from eyes and skin should be observed 5.3.3 Nonionic Silicon Softener Non‐ionic Silicon Softener is an economical silicone softener in paste form. It gives excellent limp and surface smoothness to garments and fabrics. Advantages • Imparts a soft touch • Imparts smooth feel • Imparts crease recovery Properties Appearance Transparent viscous liquid Composition Blend of amino silicones and urethane Ionicity Non‐ionic pH (1% solution) 7.0 ± 1.0 Solubility Soluble in water in any proportion Application pH range 4.5‐5.5 Solid Content 70%
