Textile printing has seen a number of innovations in printing methods since hand block printing were first superseded by machine methods. Thechangeover from traditional design work to using a CAD system can be a verypositive experience. The main use of CAD system are the creation of originaldesigns, or the interpretation of artwork supplied by customers, the latterbeing either painted artwork, fabric samples or possibly black and white filmnegatives.

Key words: CAD, printing, digital ink jet printing

Printing is an art. Printing can be defined as localizeddyeing, which can produce designs of numerous innovative ideas and thinking.Traditionally, a technique for applying under pressure a certain quantity ofcolouring agent onto a specified surface to form a body of text or anillustration.

Fabric Printing Methods:

Blotch Printing: Printing instead of dying theground color of a fabric. The result is that the reverse side of the fabric istypically white.

Discharge Printing: Using chlorine or other chemical toremove areas or previously applied color on a fabric and replace with areas ofwhite patterns on a colored ground.

Dye Sublimation: Printing that occurs when asublimation of dyes is transferred from a carrier roll and applied to thefabric/ substrate through the application of heat.

Rotary Screen Printing: Hollow, perforated nickel screencylinders are prepared for each individual pattern color involved in a design.Color is then forced sequentially through the metal rollers directly to the surfaceof the fabric.

Screen Printing: Method of adding a print via one color per screen, one at a time.

Spray Jet: A Spray nozzle individually applies color directly to thesubstrate.

The major problem with all of the traditional printing methods, block printing, rotary screen, flat bed, engraved roller, etc., is that thesemethods rely upon the production of a design on a block, screen, or roller. The production of high quality screens or rollers is a complex, costly to make,costly to store, can become blocked or damaged and need replacement, and mustbe cleaned and dried after every production run. For all these screen androller printing methods, over half of the total production time is expended onengraving and sampling. Other disadvantages are high wastage of fabric and print paste and high labour costs.

It can be readily seen that the analogue approaches in conventional textile printing methods now have some severe limitations for themodern printed fabric market. Printers now have to 'think digital' if they wantto survive and prosper in an extremely cost-conscious and cost-competitiveglobal market.

Digital ink jet printing has some considerable advantagesover conventional textile printing methods because no screens or rollers arerequired. In digital ink jet printing, print heads, containing banks of finenozzles, fire fine droplets of individual coloured inks onto a pretreated fabric. The print design is created digitally and the ink droplets are mixed togetheron the fabric surface to create the final colour.

References

1. Arun, A. 2000. Implementation of CAD/CAM in textile industry. Textile Trends. XLIII(6):27-34.
2. Balasubramanian, M and Vijay, K. 2000. CAD/CAM systems in textiles-Part I. Textile Magazine. 41(12):51-55.
3. Holme, I. 2006. Digital ink jet printing of textiles. Colourage. LIII(4).103-109.
4. http://en.wikipedia.org/wiki/Image:Adobe_Photoshop_CS2.png
5. http://eng.dgen.com/products/products02.asp?cate_num1=1&cate_num2=14&idx=9
6. http://www.digitaltextile.com/equipment.htm#shirt
7. http://www.digitaltextile.com/index.htm
8. http://www.dupont.com/inkjet/en/artistri/artistri/html
9. http://www.dupont.com/inkjet/en/artistri/index.html
10. http://www.dupont.com/inkjet/en/artistri/index.html
11. http://www.first2print.com/digital-textile-printing.php
12. http://www.jesseheap.com/dye-sublimation-software.php
13. http://www.planetphotoshop.com/pick-a-new-picker.html
14. http://www.planetphotoshop.com/step-and-repeat-inphotosho.html
15. http://www.textronic.com/flat_bed.htm
16. http://www.textronic.com/rotary_screen.htm
17. Nair, G. P. and Pandian, S. P. 2006. Spotlight on Inkjet Printing Machines. Colourage. LIII(3):89-92.
18. Patra, A.K. 2005. Digital printing-trends and techniques. Colourage.(Annual).161-167.
19. Profiles & Product. 2006. VARAD digital screen printing machines. The Indian Textile Journal. 116(4):39.
20. Technology & Products. 2006. d.gen 740TX/C- Digital textile printer. Asian Textile Journal. 15(9):96.

About the Authors:

The authors are associated with Department of Clothing & Textiles, G. B. Pant University of Agriculture & Technology, Pantnagar, Udham Singh Nagar (Uttarakhand).

Ms. Ruchi Kholiya is pursing her Phd., Ms. Shahnaz Jahan is the Professor and Head of Department & Ms. Rita Raghuvanshi is the Professor and Dean of Home Science College.

Digital Textile Printing Benefits:

• Permits customers to control the design and printing process from remote locations.
• Virtually eliminates the expense and time of screen printing preparation.
• Makes Just In Time (JIT) delivery and Quick Response possible.
• Can virtually eliminate the threat of design theft before market release.
• Facilitates the increase in the number of fashion seasons.
• Prints directly from easily stored, transmitted, and transported computer files.
• Reduces the space necessary for archiving art, films, plates, and screens.
• Is more cost effective for proof and short-run printing than analog printing methods.
• Reduces proofing time from weeks to hours, thus accelerating design and product development.
• Permits customization and personalization. Allows for design correction and modification at any time without significant schedule delays or cost increases.
• Eliminates the design and process distortions associated with on-contact analog printing.
• Is cleaner, safer, and generally less wasteful, and less environmentally hazardous than analog textile printing methods.
• It has been established that, thanks to digital printing technology, designers can now reduce textile research and pattern design time by over 50%.
• The designer can now see how a particular piece of fabric or garment will look in different colours and shapes without having to commit to a final product.

On the basis of above advantages we can say that the changeover from traditional design work to using a CAD system can be a very positive experience. The main uses of CAD system are the creation of original designs, or the interpretation of artwork supplied by customers, the latter being either painted artwork, fabric samples or possibly black and white film negatives.

Scanning artwork: Generally uses of textile design systems start with work created on paper or other medium. Most companies making printed textiles use scanners to capture data in digital form. Scanner can also be used to scan in black and white, artwork and separates. We can also scan black and white film, and then merge them back into a coloured design in our design station. Of course, the great advantage is that a user can undo any element so that mistakes or unwanted effects can instantly be corrected. Other systems use digital cameras as a means of data capture.

The editing of designs: The first step in editing a design is to take the scan file and do some colour reduction to get the file as close as possible to the final number of colours that the finished design will have. Some of this will be done by the colour reduction function in the CAD system, where the computer picks the next closest colour left in the palette to replace the colour to be discarded, or we choose which colour we want to replace the colour being discarded. We then use CAD systems to manipulate the image, changing colors, adding, deleting, moving or copying elements and putting them overall into a suitable pattern repeat.

Software packages now have a wide range of effects such as water color and oil which enable different results to be created with the same input devices. The next thing is to put the pattern into repeat. If the design was painted in repeat, it is just a matter of trimming the design into the proper size of the repeat. If it was not in repeat, the CAD system has many functions to help create a repeat in a design. We can add areas around the existing design and fill these areas by copying motifs from the original design. The use of clone brushes is helpful in the blending of wash effect and backgrounds into the new areas of the design or the artist can draw new motifs to complete the repeat. Following this, is the cleaning up of individual images or motifs. Here we use a combination of reduce brushes, dot clear brushes, dot removal and drawing function.

Color work on CAD system: We use inkjet printer for three different purposes.

• First is for the proofing of designs in progress. At various stages of editing, inkjet proofs of the design are produced for the computer artist and the stylist to grow over and take decisions as to what still need to be done to the design.
• Secondly, full size inkjet proofs are made of the design for customer or product manager approval. This allows us to make comments or changes before any engraving is done.
• Then lastly and most importantly we use our coloring station for the creation of new color ways of patterns and for the customers approval of these colorways before actual strike offs done on a fabric.

Printings Software:

Wasatch SoftRIP TX for Textile Printing

SoftRIP for Textile Printing is equipped with a powerful suite of tools that allowed us to produce superior digital fabric output without wasted media and time.

New Color Atlas Generator

• Reproduce exact colors easily. Just pick a swatch and enter the RGB value into SoftRIP.
• The total solution package includes several pre-packaged color profiles for use with Wasatch Softrip.

Manage Colorways

• Store unlimited colorways for future use.

Efficient Repeats

• Save computer time, memory, and money by efficiently printing endless repeats. Customize repeats with advanced controls.

Adobe Photoshop

Adobe Photoshop, or simply Photoshop, is a graphics editor developed and published by Adobe Systems. It is the current market leader for commercial bitmap and image manipulation.

Multiple Layer Control: Select and move, group, transform, and warp objects more intuitively by clicking and dragging directly on the canvas. Easily align objects with Smart Guides.

Nondestructive Image Correction: Improve the color, contrast, and dynamic range of any image using a comprehensive set of professional correction tools and nondestructive adjustment layers, which display corrections while preserving the original.

Step-and-Repeat in Photoshop:

Step-and-repeat" is the term used for the process of duplicating an object and spacing.

Pick a New Picker:

• Color picker uses a color wheel instead of swatches.
• Painter's Picker allows us to quickly find and select any color's complementary color, and notes which colors we should stay away from, like those that clash.
• We can choose colours from five kinds of analogous schemes, five kinds of tetradic schemes, two kinds of triads, four complex complementary schemes.

d.gen Textile Software Rip

d.gen Textile Software Rip is optimized textile software Rip for digital textile printing. d.gen Rip is a professional solution which can digitally print colors with efficiency in textile market.

Product features: 

Pointcarre-Textile Software

With Pointcarr design software we can prepare artwork for any type of textile end use. Quickly modify, color reduce, and put all our patterns into repeat.

Creation

Pointcarr provides us with a variety of tools and features for a free expression of our creativity. The tool icons are common graphics that are similar to those used in other popular graphic software.

Design in repeat

Work directly in repeat mode. Choose any kind of repeat: straight, half drop, mirror, with or without overlap.

Clean-up

Quickly and easily clean up any scan of artwork, sketches, or photographs.

Textures

Enhance your design by shading any texture over your design for realistic fabric renderings.

Compatibility

Start working from photographs, scanned images or draw directly on screen. We can even drag and drop images from popular graphics software such as Photoshop directly into Pointcarr. These images can be copied, modified, or incorporated into other designs at any time with a click of the mouse.

Color reduction

From a scan, quickly and effectively create flat artwork with the color reduction tool.

Colors

Changing color in a design is easy. Open the customized palettes and drag and drop a hue directly on the pattern. Save time by building up the seasonal collections.

Accuracy and interactivity

Pointcarr features familiar icons such as the pencil, paintbrush, rubber stamp, airbrush and eraser. With them, we can create a great variety of effects. The zoom, the customized grids and the instant screen preview guarantee an accurate and permanent control over the design.

Libraries

• The software CD-ROM also includes various libraries: textures (woven, knit),
• Knit and embroidery stitches. Add your own for a greater variety of effects.

DIGITAL PRINTING MACHINES:

VARAD digital screen printing machines

• M-Tex Machines Pvt Ltd, Mumbai offers VARAD digital textile screen printing machine, which has the highest accuracy and best repeatibility.
• Its robust cast iron body ensures longest life.
• Other salient features include high production and power saving due to use of latest digital servo drives.
• The screen printing machine includes an efficient and economic dryer. It is simple to operate with user-friendly aspects, entailing less maintenance.
• It has special features for knit goods printing.

d.Gen 740TX/C-Digital textile printer

• d.gen 740TX/C is able to directly print on most kind of fabrics including silk chiffon, stretchable fabrics such as knitted fabrics, even some spandex.
• Digital Textile Printer, d.gen 740TX/C enables us to produce strike-off within a day and guarantee professional textile printing and high profit-business in high end fashion industry, home furnishing and decorative fabric markets using garments, curtains, beddings, art walls, sofa and cushions.
• d.gen 740TX/C, is able to produce a sample within a day with much lower cost than traditional way.

Cromos of Dua Graphic systems (DGS), Italy

• Basic printer is Tx-2 of Mimaki, Japan using piezoelectric print technology.
• Printing width is up to 1600 mm and printing is done with the help of 8 heads with 16 colors(8x2) in Cromos of Dua Graphic systems (DGS).
• Printing speed ranges from 6.6 m²/h to 28 m²/h and dot size of fine, medium, large or variable can be selected during printing.
• Usable inks are reactive, acid, disperse, pigment and sublimatic.
• Adhesive printing belt plus integrated cleaning and drying mechanism make it possible to print all types of fabrics even at a high speed.
• Cromos of Dua Graphic systems (DGS) is equipped with a printer server and DGS software MatchPrint-II for controlling and calibrating the printer.

Rotary Screen Engraver

• Rotary screen engraver has fastest speed in the world, only 8min.is required for rotary screen 60"width.
• Refillable & lowest ink cost system in the world as compare to other system.
• A-Tex plot software has the ability of auto adjustment to circumference with perfect step & repeat.
• Rotary screen engraver is easy to operate and easy to maintain.
• Maximum screen length is 2200 mm to 3500mm.
• Resolution of the machine is 360/720dpi.
• Processing speed ranges from 10 min/Screen to 18 min/Screen.
• Printing head technology is new micro piezo head with 4 x 96 nozzle.

Flat Bed Screen Engraver

• Slip-free steel band drive (patented) with hardened and ground linear guides for superb quality and high precision.
• All axes with highly dynamic Servo-motor drives.
• Material hold-down with holding devices.
• Speed- 100 mm/sec.
• Resolution- 360 dpi / 720 dpi
• Printing Head Technology- New Double High Speed Piezo Ink-Jet Head
• Software- Amber Plot Program-optional for six color printing
• Printing Head Nozzle- 384 Printing Nozzles

Digital T-Shirt printer

• Textile digital T-Shirt printing direct pigment printing on to cotton t-shirts.
• TexJet digital T-Shirt printer Ink Jet direct printing on T-Shirts, textile, leather etc. It consists of A2 size printer, table transport system, t-shirt holder, ink feeding bottle system.
• Uses water based PixoInk's pigment inks and prints on almost any kind of fabric type (White and light-coloured), with very good wash fastness properties.
• High productivity up to 60 T-Shirts per hour @ 720dpi.
• Price: Euro 12,000, including the RIP software
• Printer driver: Windows XP
• Printing resolution: Max 1440dpi
• Easy to use.

DuPont Artistri

• DuPont Artistri is a fully integrated, production capable digital printing system developed for printing on all type of fabrics.
• The system was designed for a variety of applications, including printed textiles, accessories, apparel, home furnishings, table covers, flags and banners.
• High-speed, easy-to-use digital textile printing provides unparalleled design flexibility and greater cost efficiency compared to traditional printing methods.

Conclusion

Computers are already altering not just the way we work, but also the way we think of ourselves. As we rely on this electronic tools, for an increasing number of function they start to become an extension of ourselves, this memory becoming a essential supplement to our own. Textile designers of all kind use CAD. Its influence spreads from raw material production to retail outlet. Its application range, from colour combination to create images from the abstract to photographic and graphical effects, can be used in an imaginative manner.