FINISING PRAMETERS Name : MAZADUL HASAN SHESHIR ID: 2010000400008 Batch: 13th Batch (Session 2009-2013) Department: Wet Processing Technology Email: mazadulhasan@yahoo.com (FB) Blog: www. Textilelab.blogspot.com Southeast University,Bangladesh Department of Textile Engineering PREPARED BY ©right Knit fabric Finishing The term finishing, in a broad sense it covers all the processes of making the fabric good looking, good hand feeling, luster and of course for buyer requirement. It is done after dying and before delivery to market. Various types of parameters are controlled during finishing section considering buyer requirement. The term also includes bleaching, dyeing, mercerizing etc. But normally the term is restricted to the final stage in the sequence of treatment of Knit fabrics after bleaching and dyeing. However, fabrics which are neither bleached nor dyed are also finished. The aim of finishing is to render textile goods fit for their purpose or end use. Besides that, finishing can be done for achieving the following purposes- a) To improve fabric attractiveness. - By modification of fabric appearance(optical brightening), -By altering fabric handle (Softening, Stiffening) -Control of fabric dimension (Sanforising, Compacting) b) To improve service ability. -Protection of fabric (Flame proofing, Water proofing) -Improved performance (Water repellency, Raising) -Easy care properties (Resin finish, Crease recovery) Objects of finishing: Achieving finishing target of knit fabric means to achieve the finished fabric with all the quality or parameters that is required by the customer. In case of knit fabric, target quality refers to the shade, GSM, shrinkage, spirality, color fastness etc. When order is placed, at first fabric structure, GSM, shade is considered. Depending on the parameters yarn count, m/c gauge, stitch length, machine dia, yarn type are selected all those factors are related with target quality. Grey fabric gsm should be lower than finished gsm. In case of knitting fabric at least 15% weight will increase during wet processing. Grey gsm will depend on the shade percentage, lycra %, type of yarn used and type of finishing pequired for that particular fabric. For light shade stitch length will be more than deep shade. In case of spirality, it will depend on the yarn count, compactness, feeder no. of the knitting machine. If count (Ne) is high, compactness of the fabric is more and feeder no. of the m/c is lower than fabric spirality and shrinkage will be less. Finishing & Finishing Target: Yarn count and m/c gauge are related to each other and if those two factors are not matched then faults will be occurred on the fabric. For example, 20’s for 20G/18G, 30’s for 24G, 40’s/28G will yield lower spirality and shrinkage. In case of wet processing, shade must be developed in the dyeing laboratory and should be approved by the buyer. The recipe that is developed in lab is used by reducing in quantity for bulk production. Because dye pick up percentage is always high in dyeing m/c. Shade should be kept in deeper condition before dropping of dye liquor from dyeing m/c. because shade could be lighter during soaping. In case of finishing process, padder pressure, temperature, fabric speed, chemicals and finishing line should be determine by considering the finishing target because, all those factors may affect fabric shade. When fabric is unloaded from m/c water content is about 200% in case of knit fabric. Thus hydro-extractor, de-watering m/c are used before drying the fabric. Otherwise heat consumption for drying process will be huge and that is not cost effective. In this section finishing chemicals can be applied to the fabric. Finishing & Finishing Target: Drying machine is used to evaporate water remaining in the fabric after de- watering process and to obtain fully dried fabric. Fabric dia will reduce during relax drying process and tube fabric is finished in this machine. Thus tubular fabric dia should be kept more than the required finished dia in de- watering machine. This dia will be reduced in drying machine. After that tube compactor is finally used to achieve target quality of the fabric. gsm can be controlled up to 10%. But in case of open line, stenter machine is used, which may control most of the parameters in knit fabric. But fabric should be in open form. Thus open squeezer is used to slitting the fabric. Then the fabric is feed on stenter where chemicals can also be applied. Fabric shrinkage, spirality, Gsm, shade, bowing effect, slanting etc can be controlled by stenter m/c. Maximum 20% gsm can be controlled by stenter m/c. Fabric shade can be controlled by maintaining temp. if shade is dark then temp. should be high and 15-20% light shade can be obtained. Finishing & Finishing Target: If shade is light in fabric then temp. should be lowered and silicon softener is used in large quantity.Then the fabric is finally finished with open compactor m/c. Maximun 14% gsm of the fabric can be controlled. If ultra-soft fabric is required by the buyer, then gsm of the fabric should be kept at least 5% more after finishing process. Softening action is done on the back side of the fabric and the fabric is again finished on stenter m/c. In case of brushing, the back side of the fabric is brushed. Loops of the fleece fabric are brushed. Fabric may feed on the m/c for 5-8 times until the target brushing action is achieved. After all those operations, quality control process of the fabric is done in online and off-line process. In online process gsm, shade, shade variation, hole patta, bowing, slanting, oil mark, chemical spot etc are checked and graded with 4 points system. In off-line QC shrinkage, spirality, gsm, color fastness, wash fastness etc are done which are required by the buyer. Finishing & Finishing Target: Sometimes problem can appear such as shrinkage, spirality, gsm of the fabric which cannot be controlled by those finishing process. In this case fabric is wetted and tumble dried to overcome those problems. By this process, sample fabric is finished at first then required tests are done on the fabric. Sometimes it is not possible to control shrinkage, gsm, spirality, and other knitting faults due to knitting m/c and yarn. In this situation, the knitting department should take necessary actions to overcome those problems. If any faults or quality problem is appeared due to dyeing or finishing the fabric should be reprocessed, such as re-dyeing, topping, stripping are done and finished again. But target should be to finish the fabric without re-processing. Above all those factors, target finished date must not exceed to finish the fabric. If the fabric is achieve with all the required quality within the target finished date then that will be said that we have achieved the finishing target of knit fabric for a particular batch. Finishing & Finishing Target: PRODUCTION PARAMETER OF STENTER [...]... COUNT FINISHED DIA 140 30/1 Machine dia=Finished dia 160 26/1 Machine dia+1=Finished dia 180 24/1 Machine dia+2=Finished dia 200 20/1 Machine dia+3=Finished dia 220 18/1 Machine dia+5=Finished dia For 1X1 Rib FINISHED GSM COUNT GAUGE FINISHED DIA 150-200 30/1 18 Machine dia 210-220 28/1 18 Machine dia 220-230 26/1 18 Machine dia+1 240-250 24/1 18 Machine dia+1/2 280-300 20/1 18 Machine dia+2/3 Relation... controlling meter scale 1 -If any fault, GSM of the fabric is reduced then to increase the GSM of the fabric dia will have to be reduced (2 – 3) inch 2 -If Over feed speed is more then Dia of the fabric will be more 3 -If Over feed speed is less then Dia of the fabric will be less 4 -If length is more then width of the fabric is reduced 5 -If length is less then width of the fabric is more N.B: Fabric speed... Speed Over feed Width of expreader setting Set-up value 100c- 120c for white shade 120c-130c for light shade 130c-140c for Dark shade 150c-170c for curing Auto Auto 3-35 m/min Depends on quality of fabric 0-40% depends on fabric construction 45-114 cm: Depends on the required width of fabric PRODUCTION PARAMETER OF SQUEZER Or PADDER Over feed and Padder pressure of Squeezing Machine: Feed roller pressure:... GSM: For Plain Interlock- FINISHED GSM COUNT GAUGE FINISHED DIA 200 40/1 24 Machine dia 180 40/1 24 Machine dia+1 220-230 34/1 24 Machine dia+2 240-250 30/1 24 Machine dia+2/3 If the fabric is to be Enzyme washed, the stitch length should be kept (10%) less than the normal range Because, enzyme wash reduces the total weight of the fabric by removing the floating fibre and hairy fibre For light color,... 18% 5 After heat set fabric dia (delivery) i.Maximum: given in heat set procedure ii.Minimum: 14% of m/c dia 6 GSM i White color: required GSM (less 50 to 55) ii Average color: required GSM (less 60 to 65) iii Black color: required GSM (less 75 to 80) PRODUCTION PARAMETER OF COMPACTOR For different type of fabric speed and compaction (TUBE TEX): Fabric Type S/J Speed ( r.p.m ) Compaction 20 8-9 % Lycra... Fabric Type of Fabric Padder Pressure Over feed Temperature Stretch (%) P1 P2 (%) (oC) Non- 2.5 2.5 25 120 8-10 Mercerized Mercerized 2.5 2.5 35 120 12 Dyed 2.5 2.5 30 120-130 8-12 White 2.5 2.5 30 120 10-12 PK Dyed 2.5 2.5 30 120-130 10-12 1X1 Rib White 2.5 2.5 35 120 5 Dyed 2.5 2.5 35 130 5 White 2.5 2.5 35 120 8-10 Dyed 2.5 2.5 35 130 8-10 S/J 2X2 Rib Parameters used for different types of fabric:... GSM varies 20-25% For dark color, grey GSM is kept less (i.e the stitch-length is large) because take up% of dark color is more and the weight of dyed fabric will be increased If the GSM varies 25-30%, it is not only necessary to control the VDQ pulley dia but also yarn tension & take up roller Parameters for cotton Fabric: Fabric Type Overfeed % Temperature0C Light Color Speed (m/min) Stretch (%)... 62” 110 7 80% back 280 255/60 74” 78” 75” 110 9 80% Fleece 260 260/65 74” 80” 75” 110 9 80% 1×1 rib 240 224/26 72” 75” 74” 110 10 80% stripe 330 340/45 62” 67” 65” 130 10 80% PRODUCTION PARAMETER OF DRYER PARAMETERS USED FOR DIFFERENT CONSTRUCTED FABRIC For cotton fabric: Fabric Type Overfeed % Temperature0C Speed (m/min) Color High G.S.M Low G.S.M 15-20 20-25 White Color Single Jersey 30 % to-40%... Ext Temp Speed (oC) Checking parameters: 1 Overfeed ( %) : It depends on fabric structure & GSM 2 Temperature: It depends on color & GSM.( normally for single jersey -1600C, for high GSM, like-fleece, it may be 2500C ) 3 Speed: It depends on fabric GSM For higher GSM, lower the speed GSM Over feed Up to 120 14-15% 120-140 12% 140-200 7-8% 200-250 5-6% Work Instruction: Type of Fabric P.I.L -10/60 100-180... 1.5-2bar 36psi Shrinkage Tolerance of Different Fabric: Fabric Type Length (%) Width (%) S/J -5.50 -5.50 Lycra S/J -6.00 -6.00 Single Lacoste -7.00 -7.00 Lycra Single Lacoste -7.00 -7.00 1X1 Rib -7.00 -7.00 Lycra 1X1 Rib -7.00 -7.00 2X2 Rib -8.00 -8.00 Lycra 2X2 Rib -8.00 -8.00 Interlock -7.00 -7.00 Terry Fleece -5.00 -5.00 Overfeed % Up Setup for Lafer compacting Machine: Overfeed % Up for Lycra Single . recovery) Objects of finishing: Achieving finishing target of knit fabric means to achieve the finished fabric with all the quality or parameters that is required by the customer. In case of knit. fabric handle (Softening, Stiffening) -Control of fabric dimension (Sanforising, Compacting) b) To improve service ability. -Protection of fabric (Flame proofing, Water proofing) -Improved. In case of spirality, it will depend on the yarn count, compactness, feeder no. of the knitting machine. If count (Ne) is high, compactness of the fabric is more and feeder no. of the m/c