Printing quality is not up to standard?

Have you ever encountered incomplete images, repeated shadows, mismatched colors, or faded prints after a few washes? Printing defects can undermine a garment’s appeal and force costly reworks. In this article, we’ll explore how to spot missing prints¹, ghosting², color inconsistencies, and fading, along with practical steps to address them.

Each defect—whether it’s a missing area in the design, a ghost-like duplicate image, or a color that’s off—points to specific technical or operational issues. By recognizing these red flags early and adjusting your process parameters, you can produce high-quality prints that maintain consistent color and durability.

I recall receiving a shipment with faint half-printed graphics. It turned out the squeegee angle was too shallow, preventing ink transfer. Let’s dive into the major defects so you can catch them before they leave your production line.

How to identify missing prints? Is the incomplete pattern an operation problem or an equipment problem?

A “missing print” is a partial or faint section of the design. This could be a tiny gap or a large unprinted patch. Spotting it early helps you correct the root cause, whether it’s squeegee pressure or digital nozzle blockage.

Incomplete prints can stem from poor ink transfer, a clogged nozzle, or misalignment in thermal transfer. If you see faint or skipped areas, check your machine calibration, operator technique, and ink flow. Quick detection keeps your production on schedule and reduces wasted fabric.

UV Dye Effect

In which printing processes are missing prints common? (Screen printing, thermal transfer, digital printing)

• Screen printing: Weak squeegee pressure, uneven screen tension, or partial screen clogging.
• Thermal transfer: Not enough heat or insufficient pressure to bond the entire design.
• Digital printing: Nozzle clogs, leading to missing droplets; pre-treatment application might also be inconsistent.

Will insufficient operating pressure and improper scraper angle lead to missing prints?

In screen printing, a squeegee angle that’s too steep or too shallow impacts ink deposit. Not pressing firmly enough can leave unfilled areas. Always confirm your squeegee angle (around 75° to 80° is typical) and ensure consistent pressure across the entire print area.

Ghosting defects: Visual error analysis of repeated and misplaced patterns

Ghosting appears as a faint second image or offset “shadow” of the main design. It confuses the final look, diminishing quality.

Ghosting is usually tied to misalignment or fabric shifting between print cycles. In multi-color screen prints, if you re-register the garment incorrectly, you get a second, faint image. Digital printing can also show ghosting if the garment moves mid-print or if the print head re-passes incorrectly.

Is ghosting related to inaccurate pattern overprinting and fabric sliding?

If your hold-down mechanisms or adhesives aren’t robust, the fabric can shift slightly, causing repeated partial prints. Overprint alignment is crucial: if the second color or pass doesn’t align, you see a “shadow.”

How to adjust process parameters to avoid "ghosting"?

• Use proper adhesives: For screen printing, a tacky pallet or clamps keep fabric in place.
• Improve registration: Automated or well-marked systems ensure each color lines up.
• Control static: Especially in dry conditions, static cling can shift the fabric as it’s lifted or re-laid.

How to determine the color difference³ problem? Why are the colors inconsistent between batches?

Color difference (or color deviation) is when a design’s hue or saturation doesn’t match previous runs or the approved sample. Let’s see how to spot it.

Color difference disrupts brand consistency. Clients notice that one batch of shirts is more faded or has a different shade than another. Checking color swatches or using spectrophotometers can quantify differences. Variation can stem from ink formula changes, drying variations, or printing environment shifts.

What are the common causes of color deviation in digital printing?

• Ink supply changes: Switching to a new batch or brand can alter color slightly.
• Rip settings: Different color profiles or outdated software calibrations.
• Temperature/humidity: Inks behave differently as the environment changes, affecting color outcome.

Will ink mixing and drying time in screen printing affect color consistency?

If you mix inks by hand, minor ratio changes lead to noticeable color shifts. Overly quick or uneven drying can also dull or alter the final hue. Consistency in mixing procedures, drying temperatures, and time is key for stable color from one print run to the next.

Does fading indicate unqualified color fastness? Which links are prone to problems?

Fading typically occurs after washing or exposure to sunlight. It points to subpar dyes, improper curing, or inadequate bonding to fibers. Let’s check the root causes.

Rapid color loss often means your printing process didn’t firmly set the pigment. Fabric pre-treatment might be lacking, or the curing temperature/time was insufficient. Different fabric blends demand tailored methods. If your design fades too soon, you risk returns and brand complaints.

What is the relationship between fading and fabric processing and printing paste curing process?

• Fabric finishing: Residual chemicals or poor pre-treatment hamper dye absorption.
• Paste or ink: Must be matched to fabric type. For instance, reactive dyes for cotton, sublimation for polyester.
• Curing: Incomplete or uneven heat press or oven setting leads to partial fixation, resulting in color bleed or fade.

How to determine whether the color fading meets the standard through friction and washing tests?

Check local or industry standards (e.g., ISO or AATCC). Typically:

1. Launder the garment in a standardized cycle.
2. Rub test (dry and wet) with a white cloth to see color transfer.
3. Grade the color retention on a scale (1–5). A rating of 4–5 is often considered acceptable.

More common printing defects and quick self-test methods

Beyond the big four (missing prints, ghosting, color difference, fading), other issues like bubbling, cracking, or poor adhesion can plague your final product. Let’s see how to spot them.

Tiny pinholes (bubbles) can appear in thick ink layers, especially in puff or foam prints. Cracking emerges if the print layer is too thick or the garment is very stretchy. Quick in-house checks like stretching the printed area or gently peeling the edges highlight potential flaws before shipping.

How to check on-site for problems such as bubbling, cracking, pattern deviation, and adhesion?

• Visual inspection: Shine a light at an angle to spot lumps or cracks.
• Stretch test: Gently pull the fabric. If the print splits, it’s lacking elasticity or adhesion.
• Hand-peel test: Lightly try peeling the design edge—if it lifts, curing or adhesive steps may be insufficient.

Are there any graphic standards or testing SOPs that can be used as a basis for quality inspection?

Many factories adopt:

1. AQL (Acceptable Quality Limit) tables to define the max number of defective pieces allowed.
2. Industry standards like ISO color fastness or ASTM test methods.
3. Internal SOPs for each print type, describing sample approval, daily batch checks, and final QC sign-off.

Conclusion

By recognizing missing prints, ghosting, color deviation, fading, and other defects, you can pinpoint the root cause—be it ink formula, machine setup, or operator error. Thorough testing and consistent process control are crucial for producing vibrant, durable prints that stand out. A robust QA system builds trust with clients and keeps your production on track.