Welcome To Modern Printing Technologies Course Instructor: MD: ALI HOSSAIN Jr. Instructor (tech). Graphic arts institute. Dhaka /14/20161

2 Watch out……….

 Major Printing Processes.  Working Procedure in the Major printing Processes.  Modern Printing Technologies. 6/14/20163

4 Major Printing Processes.  Relief Printing Process.  Intaglio Printing Process.  Offset Printing Process.  Screen Printing Process.

6/14/2016  Relief printing is a method used to make multiple images, in which ink is transferred under pressure to paper or another support by the raised parts of a prepared printing block, surface or texture. Relief Printing Process.

6/14/20166 Relief printing process contd.. Fig: Image Carrier of relief printing

6/14/20167 Intaglio Printing Process. Intaglio Printing Process. Printing Process in which ink is retained in the recessed areas of the printing plate (which is wetted and wiped before every impression) before being transferred to paper or other printing surface. Gravure printing is an intaglio process.

6/14/20168 Intaglio printing process contd.. Fig: Intaglio printing process.

6/14/20169 Definition: Offset lithography is a process used for printing on a flat surface, using printing plates. The plate is then chemically treated so that only image areas (such as type, colors, shapes etc.) will accept ink. The plate is then rolled onto a rubber cylinder applying the inked area, and in turn the rubber cylinder (or "blanket") applies the image to the paper. Offset Printing Process

Offset printing process contd... 6/14/201610

6/14/ Screen Printing Process. Screen Printing is a process, where ink is mechanically applied to a substrate with the use of a screen and squeegee.

6/14/ Screen printing process contd...

6/14/ MODERN PRINTING TECHNOLOGIES.

6/14/ Flexography The modern letterpress

6/14/ Basic parts of the press  Unwind and infeed section- The roll of stock must be held under control so the web can unwind as needed  Printing section- Single color station including the fountain, anilox, plate and impression rolls  Drying station- High velocity heated air, specially formulated inks and an after-dryer can be used  Outfeed and rewind section- Similar to the unwind segment, keeps web tension controlled.

6/14/ Flexographic Presses Stack press Color stations stack up vertically, which makes it easy to access. This press is able to print on both sides of the substrate. Model NO. FKFS STACK TYPE Application OPP. PP. PE. WOVEN BAG. PAPER etc. Printing Speed. 2~4 COLOR CYLINDERWIDTH *320~1000 6~ COLOR CYLINDER WIDTH*320~800

6/14/ Flexographic Presses Central Impression press All color stations are located in a circle around the impression cylinder. This press can only print on one side. Advantage: excellent registry

6/14/ Flexographic Presses In-line press Color stations are placed horizontally. This press prints on both sides, via a turnbar. Advantages: Can print on heavier substrates, such as corrugated boards.

6/14/ Gravure The modern Intaglio Printing Process.

6/14/ The Gravure Press and its components.  The image carrier, a cylinder engraved with the image to be printed or transferred.  An ink fountain, a large ink well positioned beneath the cylinder, extending the width of the press unit.

6/14/  A doctor blade assembly containing a blade which wipes excess ink from the non-image areas of the image carrier.  An impression roller, a rubber-covered metal cylinder which holds the substrate against the engraved image carrier to obtain proper ink transfer.  A dryer, consisting of a control source of heated air, regulated to provide optimum drying of inks or coatings and remove ink carrier vapors.

6/14/ Gravure Industry  Simplest of all printing systems.  Fastest press start up.  Very little paper waste (half the paper waste of lithography).  Speed is extremely high.  45,000 copies an hour.

6/14/ DIGITAL PRINTING ANALOG PRINTING Conventional textile printing techniques Master image present on block or screen is reproduced onto textile in the form of print. DIGITALPRINTING Design is in the form of electronic file in a computer. The computer is linked to a suitable machine e.g. inkjet printer Design is printed onto paper or fabric in the form of analog image with the help of color microscopic dots.

6/14/ Trends in global printing market Digital printing technology supports the present industrial trends: short runs at economical cost, quick delivery, exclusive unique designs and personalized textiles. It allows the user to bypass the extremely time consuming and expensive screen making process, providing the opportunity for quick changes to colour or design elements. The conventional printing requires 6-7 weeks whereas the digital printing requires about 2.5 weeks delivering the final printed products

6/14/ Directing small droplets (usually between 50 and 60 microns in diameter), of ink from a nozzle onto printing substrate. The droplets can have different colors. Droplets are combined together on the substrate to create photo-quality images. Positioning of droplet is controlled by high frequency digital signals from computer. Droplet formation involves application of a controlled pressure on liquid ink in its reservoir as it streams into the printing nozzles the ink stream is broken into droplets. Different technologies for application of pressure on liquid ink.

6/14/ two main technologies Both technologies use large number of nozzles ( Micron dia,) for each colour (CMYK) Between 1000 to million drops processed per second. Depth of shade is controlled by number of drops applied on substrate.

6/14/ Advantages ability to cover a larger band width print area with one pass Higher productivity compared to single jet system long print head life over thermal or piezo drop on demand printers. Disadvantages High initial cost of the system Low resolution Extremely low viscosity ink (3-6 CP) and electrical conductivity. In general, the initial high cost of CIJ heads currently prohibit their use for low volume applications.

6/14/ Some Digital Printing Machine.

6/14/ Digital Offset Printing

6/14/ Digital Offset Printing contd.

6/14/ Digital Offset Printing Contd.

6/14/ Modern Screen Printing CAROUSAL PRINTING MACHINE These machines will be available both in automatic and semi automatic machines and with 4, 6, 8, 10 & 12 multi colour models. The double spring model gives the customers a maintenance free performance of the machine. Electric heat panels included in the machine.

6/14/ Garments Printing Flock Printing:  Tiny particles of fiber are made to adhere to a fabric surface in conformance to a particular design. Rayon and nylon fibers are typically used for flocking.  The ability of flocked fibers to withstand dry cleaning and/or laundry depends on the adhesive. Adhesives with excellent fastness to cleaning processes are used.

6/14/ This involves printing with a chemical that will destroy the fiber in the patterned design print area. 2. In fabrics that are made with blended yarns, the burn-out chemical will destroy one fiber and leave the other undamaged. Unusual and interesting fabrics can be created by this method. Burn-out Prints

6/14/ Print some pattern with the foil on the fabric or paper for shinny effect. Foil print is the foil paper. it is heat transfer Chemical in use:-  Gum mix binder.  Heat press foil.  Time sec & temp c Time: pieces/min. Fault:-  Color shade  Design  Placement design ok  Gum mistake then foil mistake& heat problem then print problem. Foil print:-

6/14/ Digital printing HOW IS IT DONE? inkjet printers print CAD designs directly onto fabric using special printing inks. This is a flexible form of printing suitable for short runs and for producing fabric samples.

Thank you 6/14/201637