The Practical Code for Surface Printing on Stainless Steel Water Bottles (Part 2)

Every cup holds a story, and life is filled with warmth. Hello everyone, "Dong Dong's Cup Talk" is back! In my previous article, I shared insights about heat transfer printing for water bottle surfaces. Today, I've invited Mr. Zhou, http://www.zhanyict.com/en/ProductsDetail-VB-10405.htmlour factory's pad printing specialist, to share professional tips on what to watch out for in pad printing. Due to the extensive content, I'll break it down into multiple articles.

III. Life-or-Death Differences: Stainless Steel Pad Printing vs. Other Materials

Stainless Steel Water Bottles

- Surface Energy: http://www.zhanyict.com/en/ProductsDetail-VB-10405.htmlMust be enhanced to ≥38 mN/m (original value: 28-32)

- Ink Type: Epoxy-modified two-component ink

- Post-Curing: 160°C × 30 minutes baking

Plastic Water Bottles

- Surface Energy: Requires corona treatment to ≥44 mN/m

- Ink Type: http://www.zhanyict.com/en/ProductsDetail-VB-10405.htmlPolyurethane one-component ink

- Post-Curing: 80°C × 15 minutes or UV curing

IV. Eight Common Pitfalls in Pad Printing and How to Solve Them

1. Sawtooth Pattern Edges

- Cause: Silicone pad rebound speed >500 mm/s, causing ink tearing

- Solution: Use slow-rebound silicone pads (300-400 mm/s)

2. Insufficient Color Saturation

- Cause: Insufficient etching depth on steel plate (<0.02 mm)

- Golden Parameter: http://www.zhanyict.com/en/ProductsDetail-VB-10405.htmlBlack ink plate depth = 0.025 mm; light-colored ink = 0.018 mm

3. Misalignment in Multi-Color Printing

- High-Tech Fix: Install laser positioning tracking systems (improved alignment accuracy from ±0.2 mm to ±0.05 mm in one project)

V. Quick Formula for Estimating Printing Difficulty and Cost

Engineers' rule of thumb: http://www.zhanyict.com/en/ProductsDetail-VB-10405.htmlCost coefficient = number of colors × precision requirement × surface complexity

Number of colors (C)

Coefficient value: single color = 1, four colors = 2.5, six colors = 4

Precision level (P)

Coefficient value: ±0.3mm = 1, ±0.1mm = 1.8, ±0.05mm = 3

Surface complexity (S)

Coefficient value: http://www.zhanyict.com/en/ProductsDetail-VB-10405.htmlplane = 1, single curved surface = 1.5, multi-curved surface = 2.5

Case Study:

A four-color gradient curved bottle:

2.5 (Colors) × 1.8 (Precision) × 1.5 (Surface) = 6.75 Cost Factor

→ Processing Fee ≈ Base Price × Factor (Base price: ¥0.2/color; Total: ¥0.2 × 4 × 6.75 = ¥5.4/unit)

VI. Truths Forged Through 20 Years of Blood, Sweat, and Tears

- 0.01 mm Decides Fate: A mere 0.005 mm deviation in plate etching depth once caused 100,000 insulated cups to fail color standards (¥800,000 loss)—now, http://www.zhanyict.com/en/ProductsDetail-VB-10405.htmlevery plate must undergo 3D profilometer inspection.

- Humidity is the Silent Killer: During the 2023 humid season, uncontrolled moisture caused "tear stains" on an entire batch—now, http://www.zhanyict.com/en/ProductsDetail-VB-10405.htmldual dehumidifiers + real-time monitoring screens are workshop staples.

Stay tuned for more industry revelations in upcoming posts!