Design for spot-color production
Supply vector artwork with outlined fonts, named spot colors, final dimensions, and clear separations. Identify minimum line, gap, text, and reversed-detail sizes. Gradients, photographs, fine halftones, and many colors can be difficult or inefficient on curved drinkware; simplify the design or compare another print process when photographic detail is central to the concept.
Set artwork position relative to stable product features such as a handle, seam, front datum, or base. Confirm the printable height and width, curvature limits, taper, and distance from rim and bottom transitions. A rotary screen setup may increase coverage on compatible cylindrical forms, but handles, facets, tapers, and abrupt curves can interrupt contact and registration.
Match preparation and ink to the final surface
Bare metal, powder coating, paint, plastic, and glass present different surface energy, texture, chemical resistance, and heat tolerance. Production may use cleaning, flame, plasma, primer, or another validated preparation, but the chosen treatment must not damage the product or create an unsupported compliance claim. Test the actual finish batch rather than a substitute panel alone.
Specify an ink system intended for the substrate and use, with supplier evidence appropriate to the project. Food-contact and restricted-substance considerations depend on print location, product construction, destination, and law. Decoration is normally kept away from direct beverage contact, but that placement does not eliminate the need to review composition, migration risk where applicable, and truthful marketing.
Control screens, jigs, and registration
Screen mesh, stencil, squeegee, ink viscosity, angle, pressure, stroke, product fixture, and rotation influence deposit and edge quality. Multi-color work adds screens and registration steps. Approve a production standard that shows acceptable opacity, texture, overlap, trapping, and edge appearance. Record whether the base color needs a white or other underprint to achieve the approved look.
Fixtures should locate the bottle repeatably without scratching the finish. Monitor logo position, rotation, vertical alignment, and distortion. For tapered items, artwork compensation may be necessary. Run samples across the intended batch and operators because an initial print made slowly by a specialist may not represent mass-production speed and handling.
Validate curing, adhesion, and cleaning
Ink reaches its intended properties only after the validated cure. Time, temperature, energy, catalyst ratio, humidity, and delay before packing can matter depending on the system. Under-curing can create poor adhesion or odor; excessive conditions can affect coating, plastic, vacuum components, or color. Record the process window and verify it during production.
Agree adhesion, abrasion, cleaning, chemical, and dishwasher tests appropriate to the instructions. Define preparation, tool, force or cycle, conditioning, and acceptance. One pass of tape on a fresh sample does not establish lifetime performance. Test printed production-intent bottles and review both ink and underlying finish after conditioning.
Set visual and functional acceptance
The inspection standard should cover correct artwork and color, dimensions, placement, registration, opacity, pinholes, skips, smears, bleeding, contamination, scratches, and cure or adhesion results. Use controlled lighting and an approved sample. State where minor variation is acceptable, especially on textured coatings, instead of deciding shipment quality from whichever photo is available.
Protect prints through adequate cooling or curing time, separators, sleeves, bags, inserts, and pack-out. Test packed products for abrasion during transport. At reorder, review ink, supplier, coating, screen, artwork, and cure changes. A familiar logo does not make a new substrate-process combination automatically equivalent.
