Screen Printing Ink Tips and Tricks (click one of the following for more information) |
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Ink Build-up | Screen “Clogging” | Transfers | Color Matching |
Scorching | Nylon Jacket Printing | Ink Color Changes | Additives |
Squeegee Pressure | Flash Curing | Screen Breakdown | Puff Printing |
The Pallet | Curing/Drying | Ink Storage | Ink Blistering |
Special Effects | Off - Contact | Opacity/Bleed Resistance | Adhesion |
Viscosity | Screen Mesh | Soft-Hand Effect | Factory Environment |
1. Ink Build-up:
- Wipe Multi - Tech’s Thinner sparingly on the underside of the screen.
- Print with properly tensioned screens. High - tension stretch with as fine a mesh as possible (monofilament).
- Reduce off-contact and squeegee pressure.
- Use sharp, hard squeegee (70- Durometer) with reduced angle.
- Reduce ink viscosity with Multi - Tech’s Thinner DT and/or MSB-100 Clear/ Soft - Hand Extender.
- Add Multi-Tech thickener paste, 1% - 3%.
- Adjust squeegee speed.
- Avoid overlapping color on color. Butt-register your artwork when possible.
2. Flash Curing:
- Multi-Tech inks flash faster than the competition. Gel at temperatures between 160° F and 180° F. Pretest to determine flash parameters.
- Do not over-flash. Only gel! Ink will become “tacky” when flashed too hot and/or too long.
- Remember, platens absorb heat and can “back- flash” over an extended production run. Monitor heat/flash temperatures periodically for consistency.
- Various colors require various flash techniques. Match flash unit height, temperature set-ting and time. Flash no longer or hotter than necessary. Only gel!
- Flash additives are not necessary with Multi - Tech ink; however, a flash additive is available for specialty applications.
3. Opacity/Bleed Resistance:
- Use Multi - Tech Multi - Choice Opaque (MCO) Series for highest opacity and bleed resistance.
- On bad “bleeders,” use Multi-Tech’s MC-107 Flash Clear for underbasing.
- Do not over- cure the ink and garment. Adjust dryer temperature not to exceed 330° F.
- If garment dyes are not fully heat-set, send unprinted garment through a “hot” (400° F) dryer at slow speed (as long as possible without scorching).
- Use a coarse mesh (61-86) and deposit more ink on the garment.
- Use “thicker” emulsion (or CDF4/7) deposit on the screen itself.
- Flash-cure when necessary to control ink “pick - up” and over- printing.
- When possible, print color sequence dark to light.
4. Soft-Hand Effect:
- Add Multi - Tech’s MSB-100 Clear/Soft - Hand Extender to any MC ink in any proportion desired to maximize soft - hand. Reduce ink with appropriate modifier.
- Use Multi - Tech’s Multi - Bright (MSB) Series straight from the container. It is designed specifically for soft - hand application and it contains no water!
- Use finer mesh (196 -305) monofilament fabrics to reduce ink coverage.
- Increase squeegee speed; reduce squeegee angle.
5. Scorching:
- Match dryer time and temperature to ink and garment.
- Set and monitor dryer temperature, not to exceed 330° F at belt level.
- Reduce ink deposit, if possible, to accelerate cure time.
- Do not over-modify the ink! Too much Thinner PL (use only 1% - 5% by weight) or Thinner DT could cause longer cure times. Avoid using other brands of reducers; they are often over-used and increase dry times. Unbalanced ink formulas cause unpredictable cure parameters.
- If your dryer is equipped with jet - air, turn it on and recheck temperature.
- Raise heating element height inside the dryer.
- Reduce temperature and/or time the garment is in the heat tunnel.
- For extreme cases, when printing specialty substrates, use Multi - Tech’s Multi - Fast (MF) ink. It fully cures between 270° F and 290° F. Available in selected colors (drum quantities).
- Dryer is too hot. Reduce heat and recheck cure temperature.
- Substrate is in the heat chamber too long. Reduce dwell and recheck cure temperature.
- Some garments are treated with starches or “sizing” that turns light brown when subjected to heat. Consult fabric supplier.
- Fluctuating voltage to dryer or “voltage spikes.” Ensure that dryer is fed with the proper size wire from the fuse box.
- Check dryer controls, heat sensor, contacts, air-flow, etc.
6. Curing/Drying:
- Cure the ink at 320° F for approximately 90 seconds (time will vary based on ink deposit, substrate, etc.)
- Do not cure too hot! This can cause “blistering” and/or sublimation.
- Periodically check substrate for cure (solvent test, stretch test, Thermo-Tels, wash test).
- Chart dryer settings, ink use, substrate performance, mesh use, etc., for consistency and history purposes.
- Understand that a change in dryer belt speed (time) will result in a change in curing temperature. Pretest temperature after adjusting belt speed.
7. Squeegee Pressure:
- Less pressure is better! Only use what you actually need.
- Too much pressure can cause ink build - up, dot gain/ smearing, excessive penetration (less opacity), reduced ink mileage.
8. Off - Contact:
- Use off - contact to compensate for poor screens and to help clear the mesh of ink. Also assists in “sharpening” the print.
- The tighter the screen fabric, the less off - contact required! Use as little off - contact as possible.
9. Color Matching:
- Use Multi - Tech’s exclusive Multi - Match Ink System. Use nine toner colors plus a tinting white and black. Over 1000 standard formulas available. Multi-Match inks are finished/ complete single - pigment inks for absolutely “clean” mixing. Multi - Tech is now licensed to simulate Pantone* Matching System Colors. Ask us about this opportunity.
- Multi - Tech’s standard MC and MSB colors can also be intermixed; because of their “clean” use of pigments, shading and color matching are relatively easy.
- Base pigments and clears are also available for those who really want to “build” their own ink.
*Pantone Inc.’s check-standard trademark for color reproduction and color reproduction materials.
10. Screen Mesh:
- Mono- filament polyester is recommended.
- Match screen mesh to particular application. Coarser meshes (61-110) for heavy deposits; finer meshes (125-196) for overlays, nylon jackets, general application; and extra - fine mesh (230-305) for process - printing, soft - hand and special effects.
11. The Pallet / Platen:
- Use a hard platen for nylon mesh, jacket printing, and general - purpose printing.
- Use a soft pallet for heavy ink deposit, rough substrate surfaces, puff and extending flashing application.
12. Additives:
- Always stir ink prior to using an additive. This will break up “false body.”
- Do not overuse! Consult us if you have questions. Don’t guess!
- Be aware. Some additives can affect dry/cure times and temperature.
- Only modify ink being used for a particular job, not the entire batch. This will help avoid over modification.
13. Special Effects:
- Phosphorescent glow - in- the -dark inks: available as finished ink, MC -102, or as powdered pigment for specialty applications with base.
- Glitter: silver and gold are standard -specialty colors on request. Print with 38 -61 mesh.
- Puff Concentrate. Add 25% - 40% by weight to Multi - Choice or Multi - Choice Opaque and make your own puff ink.
14. Transfers:
- Use MC or MCO series. Great for general or “hot-split” use.
- General transfers: use 86 -158 mesh. Print on Transfer- Rite - 75 or Transfer - Rite Parchment. Hot- split transfers: use 38 - 86 mesh (butt - register, no overlays), print on Soft-Trans - Paper. Multi - Tech has a hot - split additive for special use, if necessary.
- Transfers dry much faster than direct - print garments. Dry time ranges from 20 to 45 seconds. Only gel the transfer. Do not fully cure.
- Gel at lower temperatures, usually between 220° F and 240° F, depending on ink deposit.
- Use Transdust to promote transfer adhesion when necessary.
- Pre-shrink paper by running it through the dryer prior to printing.
15. Puff Printing:
- Use Multi-Puff or Multi-Puff Concentrates (25% - 40% by weight).
- Use coarse-mesh fabric (38-86) for high puff and finer meshes (110 -125) for lower and detail puff.
- Use a “thick” stencil/ emulsion screen. Capillary films are best.
- “Stack” the print (print - flash-print) for extra high effect.
- Do not cure too hot or too long, as puff can collapse under too much heat.
- When printing large solids, use half-tone dots/mezzotints to avoid “puckering.”
- Always print puff as the last color.
- Use a soft pallet to deposit more ink and achieve a higher puff. 16. Odor:
- Usually garment- dye- related. Exhaust your dryer properly.
- Multi - Tech Opaques (MCO’s) have less odor than other brands.
16. Ink Color Changes:
- Inter- color dynamics (pigment interaction) on overlays. Multi - Tech inks have fewer and cleaner pigments.
- Curing too hot (375° F - 400° F) can cause scorching and color change.
17. Ink Blistering:
- Reduce flash - cure temperature.
- Reduce dryer temperature.
- Watch those additives! Inappropriate use of ink additives can promote blistering.
18. Screen “Clogging”:
- Use enough pressure to force the ink through the screen and “clean” the mesh of any residue.
- Use a sharp squeegee.
- Adjust squeegee speed.
- Check mesh for emulsion residue.
- Over-use of Thinner DT or use of other non-authorized thinners (paint thinners, lacquer thinners, etc.) that can cause ink resin “swelling.”
- Adjust off - contact distance.
- Over-heated (hot) pallets from flashing can cause “clogging” in subsequent screen.
- Wash up screen at night (end of production).
19. Screen Breakdown:
- Check screen exposure. Under-exposure can result in premature breakdown.
- Properly clean, degrease and abrade screens prior to emulsion/ capillary application.
- Avoid excessive squeegee pressure.
- Do not use a squeegee longer than the pallet or too close to frame edge.
- Water in inks. Be careful. Some ink manufacturers use water in their soft-hand inks and don’t tell you! Multi - Tech contains no water in any of its plastisols!
- Baggy/loose screens (low tension) can result in premature breakdown.
20. Viscosity:
- “Low- Shear” viscosity. Ink undisturbed in the bucket will be thicker than under “high-shear” squeegee pressure. High-shear viscosity is the important value.
- Thin, if necessary, with Multi - Tech’s Thinner DT (1% - 3% by weight). Thins and detackifies; does not affect opacity when used correctly.
- Increase flow and penetration with Multi - Tech’s Thinner PL (1% - 5% by weight) for slight increase in “body.”
- Thicken with Multi - Tech’s Thickener Powder (1% - 2% by weight) for a more dramatic thickening effect. Use a drill mixer to stir in!
21. Adhesion:
- Use a hard (70 - Durometer), sharp squeegee and a hard pallet when adhesion is a problem, especially for nylon mesh printing.
- If the ink is “flaking,” it is probably under- cured or is incorrect for the particular fabric.
- Use Cellosolve acetate and wipe the imprint area if the use of “waterproofing” materials is suspected on the substrate.
- Use an additional catalyst if necessary. Waterproof fabrics, 100% synthetic fabrics, dense, tightly woven canvas or poplin may require a catalyst for proper adhesion.
- For athletic printing, use MC-1030 Athletic Additive for increased adhesion, abrasion resistance and elongation.
22. Nylon Jacket Printing:
- Use a hard, sharp squeegee on a hard pallet.
- Use 125-196 mesh for general purpose, 230 -305 for detail and process printing.
- If using a two - part nylon system, ensure proper use of catalyst.
- Use jet - air and dry between 305° F and 320° F for recommended time.
- Pre - flash consistently to control nylon shrinkage immediately prior to printing.
- Post-cure occurs for an additional 48 hours after printing.
- Must flash between every color for multi - color printing. Avoid extended flash times that can cause shrinkage and registration problems.
23. Ink Storage:
- Store in cool (65° F - 72° F), dry environment. Inks “stiffen” up when too cold and “age-up” when too hot.
- Do not store in direct sunlight.
- It is advisable to always store ink with its lid on.
- Stir ink prior to use.
24. Factory Environment:
- Be aware! Be conscious of basic surroundings, temperatures, etc.
- When encountering problems, look at everything, not just the symptoms. Ask yourself, “What could be the real cause?”
- Items often overlooked:
- Temperature
- Ventilation
- Drafts/fans
- Lint
- Electric wiring (usually too small)
- Separate electrical circuits for items that draw significant electricity
- Extension cords (too small or too long)
- Low or varying voltage
- Dryer settings
- Lighting
- Cleanliness/dirt Catalog your positive results, and negative ones as well, for future reference.