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Introduction Of Finishing And Resin Finishing By Aravin prince I M.Tech ( Textile Technology) aravinprince@gmail.com INTRODUCTION& IMPORTANCE OF FINISHING The ultimate aim of a finishing process is to develop and or modify the fibers or finishes for conventional synthetic fibers so that they give the comfort of natural fibers , the richness of animal fibers A finishing process in which a desired quality or qualities are imparted to fabric in order to improve the appearance, to affect stiffness, weight, elasticity, or softness, to facilitate care, or to protect the wearer. Examples include calendaring, durable press finishing, water and oil repellency, and softening aravinprince@gmail.com CONTD… As the name implies, it is the last step or the process in the method of conversion of fiber into fabric which is in the marketable or useable form. After finishing only the steps of inspection and packing are left to make the fabric ready for shipment or marketing. aravinprince@gmail.com FINISHING GIVES THE FOLLOWING ADVANTAGES: Improved appearance – luster ,whiteness etc., Improved feel which depends on the handle of the fabric and its softness, suppleness, fullness etc., It improves the wearing qualities – Non soiling anticrease. It gives special properties required for particulars uses – water proofing, Flame proofing etc., It covers the faults of the original cloth It increases the weight of the fabric It increases the sale value of the material. It improves the serviceability of the fabric. Hence finishing is essential for a textile good before they are put on the market. aravinprince@gmail.com CLASSIFICATION TEXTILE FINISHING CHEMICAL MECHANICAL REACTIVE TYPE DEPOSITION TEMPORARY PERMANENT OF FINISH TYPE OF FINISH E.g. Calendaring Eg.Raising, Sanforising Parchementising TEMPORARY PERMANENT (Stiff& Transparent) Starch E.g., Synthetic resin Chlorination of wool China clay (Crease resistance, Wash (Antishrink) (Stiff) & wear Durable press) Mercerizing Oils, Fats & China clay (Stiff) Velan Pf waxes (soft) Rubber coating (Flame retardant) Optical (water proof) Ethylene oxide- brightening Cellulose Acetate Formaldehyde cellulose ether (stiff) (Soil release) Phosphorous& Nitrogen compounds (Flame retardant) All are permanent aravinprince@gmail.com Finishing Is Commonly Divided Into Two Categories Chemical Mechanical. Chemical Finishing In chemical finishing, water is used as the medium for applying the Chemicals. Heat is used to drive off the water and to activate the chemicals. Resin treatment Softener treatment Powder Coating Soil/Stain Resist Fire/Flame retarding Special Purpose aravinprince@gmail.com Mechanical Finishing It is considered a dry operation even though moisture and chemicals are often needed to successfully process the fabric. Calendaring Pitching/Raising Sanforising Heat setting Type Of Finish (Durability) Finishing mainly falls into three groups; 1. Temporary finish 2. Permanent finish 3. Semi-permanent finish aravinprince@gmail.com RESIN FINISHING Cotton is mainly selected for apparel purpose because of its durability, ability to withstand the rough laundering tr eatments especially under alkaline conditions, good perspiration absorption characteristics, and comfort during wear and ability to take up a wide range of dyestuffs. However, proneness to creasing under slight crushing and retention of the crease for a long time give cotton garments a poor rating during actual wear. The ability of a fabric to resist the formation of crease or wrinkle when slightly squeezed is termed as crease resistance. The ability of a fabric to recover to a definite degree is called crease recovery of the fabric. aravinprince@gmail.com Contd… Obviously Resin Finishing is the process of bringing out a special property of „crease recovery‟ to Cotton. Resin finishing often known by various fancy terminology is an important process of textile processing. Resin finishing quite often called “ Wash & wear finish” “Anti crease finish” “Crease resistant finish” “Durable press finish” And “ wrinkle free finish” is gaining importance today aravinprince@gmail.com Contd… Resins are cross linking agents, which form covalent bond on reaction with –OH groups of cellulosic materials in acidic medium at a pH of 3-4. aravinprince@gmail.com [...]...RESINS MAINLY FALL INTO TWO GROUPS aravinprince@gmail.com Deposition type of resins Cross linking type of resins Deposition type of resins This type of resins is deposited on the fabric as surface coating No reaction will take place between the fiber and resin They include Phenol-Formaldehyde resins Urea formaldehyde resin Alkyd resins Ketone resins Vinyl resins Cross Linking Type Of Resins... aravinprince@gmail.com fabric is padded with 250 gpl resin along with necessary additives, dried and the fabric is converted into garment form and actual curing is carried out followed by a cold wash and soaping to remove the unfixed resin QUALITY CONTROL METHODS aravinprince@gmail.com Estimation of Wet Pick Up of Resin Unfixed Resin content CRA Number of cross links formed by chromatography Loss in Tensile... only way left out will be to prevent disortion of Hydrogen bonds which is being perfectly carried out by means of BLOCKING the Hydrogen bonds forming groups by means of cross linking of –OH groups of cellulosic chains CATALYSTS Various Catalysts have been suggested and reported in literature which exhibits their own influence on the fixation of resin and in turn on the CRA The catalysts mainly are... improves the Crease Resistance and Crease Recovery property It reduces the shrinkage of the fabric during laundering It imparts a smooth and quick drying property It improves Resilience, Handle and Draping quality It improves the weight and Dimensional stability It increases the strength of RAYONS in both wet and dry state It gives resistance to degradation by light and laundering It improves... place results in as CREASE and since cotton is not a elastic material it can not regain its original shape and position and hence the deformation that resulted remains as SET CREASE aravinprince@gmail.com MECHANISM OF CREASING Why do some fabrics wrinkle and others don't? Close examination of this question reveals a relationship between moisture absorption and wrinkling Wool and cotton fabrics wrinkle,... laundering It improves the fastness to Light and Washing of many dyestuffs It prevents the Inter molecular slippage in the fiber core It becomes partially water proof and Rot proof Disadvantages aravinprince@gmail.com It decreases the Tensile strength and Tear strength It decreases the Abrasion resistance It gives an unpleasant odor It gives unwanted Harsh and Stiff feel It turns the fabric yellow... further polymerize to form resins The following are some of the cross liking agents mostly used for crease resistant finishing DMU (Dimethylol Urea ) DMEU (Dimethylol Ethylene Urea) DMDHEU (Dimethylol Dihydroxy Ethylene Urea) DMPU (Dimethylol Propylene Urea) TMM ( Trimethylol melamine/ Melamine formaldehyde Objective The main objective of resin finish Keep the fabric flat and smooth and Free from undesirable... water Polyester and nylon fabrics are more resistive to wrinkling, they absorb much less than the other two To understand wrinkling of cellulose fibers, consider the stress and strain forces within the cellulosic chain The stretching stresses a t the outer reaches of the bend provide lateral forces to adjacent polymer chains which can cause them to move aravinprince@gmail.com MECHANISM OF CREASING... The stressed shape of the fiber is just as stable now as was the original shape THEN HOW TO MAKE COTTON CREASE RESISTANT ? It is clear now that the weak Hydrogen bonds gets disturbed during the course of washing and on drying they try to rearrange and reform giving rise to creases aravinprince@gmail.com From the mechanism of creasing either we have to Prevent disortion of hydrogen bonds Make cotton... understand that Elastic materials like rubber do not form creases We know that rigid materials like metals do not form creases Cotton is not * RIGID and therefore bends and the deformation results in as CREASE * ELASTIC and therefore can not regain its original shape and position after deformation * It is clear that when a load is applied on cotton material, since it is not rigid will bend and deformation . Introduction Of Finishing And Resin Finishing By Aravin prince I M.Tech ( Textile Technology) aravinprince@gmail.com INTRODUCTION& amp; IMPORTANCE OF FINISHING The ultimate aim of a finishing. type of resins Cross linking type of resins Deposition type of resins This type of resins is deposited on the fabric as surface coating. No reaction will take place between the fiber and resin. . include Phenol-Formaldehyde resins Urea formaldehyde resin Alkyd resins Ketone resins Vinyl resins aravinprince@gmail.com Cross Linking Type Of Resins o These types of resins chemically react with the fiber and cross