Printing• Printing is applying color only to defined areas of a substrate to obtain the desired pattern.• There are basically two types of printing: (i) discharge printing (ii) direct printing• Pigment dyes and reactive dyes are used in the company.
Hand Screen Printing PurposeSampling Process Check the out come Screen Printing consists of three elements : Mesh Stencils Squeeze
Hand screen printing• Printing process involves following steps: The print paste is prepared using binder, water and dyestuff.1 kg binder is used for every 10 g of color. The table top is a sandwich of a rubber blanket, a cotton fabric and a resin coated screen. The fabric is glued on to the table top & the screen is placed over the fabric; the print paste is poured over it and spread on the fabric manually by a wooden squeegee.
Rotary Sample Printing Machine Machine used • Sampling Machine – Baby Rotary • To check the fabric in garment form. screen printingMachine Parts -•Transporting Roller•Crease Removing Roller•14 Printing Rollers•Nickel Screen
Screen development• Nickel screen mesh is coated with photo-emulsion.• The screen mesh is dried at 150˚C for 5 minutes.• The machine has software which is used to print designs. The design is fed into the machine using a CD.• As per the design entered, photo-ink is sprayed on the mesh. The ink displaces the photo-emulsion.• It is then washed with water to unclog the pores and after this the screen is ready to be used.
ROTARY SCREEN PRINTING• Name of the machine – Ichinose• Used for the bulk production.• Average speed of m/c - 16 m/min.• Average productivity – 8000-10,000 m/shift• Maximum no. of screen possible – 14• Speed : complexity of design increases – speed of the production decreases.• Average speed - 16 m/min
Printing paste preparation• The ingredients found in paste formulations include the following: dyes or pigments, thickeners, sequestering agents, dispersing or suspending agents (surfactants), water-retaining agents (humectants), defoamers, catalysts, and hand modifiers.• In addition to the ingredients, pigments require a binder or resin system to fix the pigment and may include adhesion promoters• For blended fabrics pigments are used, which are not dyes but are colored particles glued to the surface of the fabrics.
Soaping and washing• After the printing is over the printed fabric is sent to soaping/washing and then dried.• Soaping is done after pigment printing and washing is done after discharge printing.• Yamuna soaper machine is used for washing, soaping and drying.• Machine runs at the speed between 10 Mts. /min to 30 Mts. /min.• Contact time between the printed fabric and soaping agent is 5-6 minutes.
Printing defectsSome of the printing defects are: Improper positioning of print Fluff Sharpness/blurr Joint marks