Understanding Tinplate Printing: Processes, Characteristics, and Industry Applications

From Food Preservation to Decorative Branding

The journey of tinplate packaging began in 1819, when William Underwood established the first tin can factory in Boston, USA. His method involved cutting tinplate sheets to size, hand-welding them into cylindrical shapes, sealing both ends with round plates, and adding a small opening for filling. Initially, the focus was purely on preserving food quality, but with time, designs were printed on the surface—turning the tin can into both a functional and decorative product that could attract consumer attention.

What Is Tinplate?

Tinplate (electrolytic tin-coated steel) refers to a thin, low-carbon steel sheet (carbon content below 0.13%) coated with an extremely thin layer of tin (0.10–0.15 μm). Its layered structure includes:

This multi-layered design allows tinplate to be used for food cans, edible oil containers, pharmaceutical tins, construction materials, household appliances, signage, and toys.

Tinplate Printing: Step-by-Step Workflow

Internal Coating for Safety and Shelf Life

Depending on the contents, an internal coating is often required to prevent corrosion of the container wall and protect the product from contamination—essential for long-term storage. For example:

• Candy tins: Coating prevents rust during edge rolling and enhances visual appeal.

• Food cans: Coatings must resist corrosion, adhere well, be flexible, non-toxic, odorless, and compliant with food safety standards, while also withstanding processes such as high-frequency resistance welding and sterilization at 121°C without discoloration or gloss loss.

Common coating types: Phenolic resin, epoxy-phenolic resin, acrylic resin, and aluminum powder coatings—chosen based on content type and required thickness.

Base Coating & White Undercoat (White Cadine)

Since printing is typically done before can forming—which involves bending, stretching, welding, flanging, and sealing—a base coat is applied to ensure ink adhesion and prevent cracking or peeling.

Requirements for Base Coats:

• High transparency with minimal yellowing

• Smooth leveling, heat curing, and flexibility

• Strong affinity with ink and adhesion to tinplate

White cadine is thicker and more opaque than white ink, offering better gloss, fullness, and surface smoothness. It contains film-forming agents, pigments, rust inhibitors, and solvents.

Comparison: White Coating vs. White Ink

Plate Making for Tinplate Printing

Plate making for tinplate differs from other substrates due to its non-absorbent surface and hardness:

1. Dot Shape Selection – Circular or diamond dots help avoid tonal jumps in mid-tones, unlike square dots.

2. Pre-Forming Allowances – Space must be left for welding seams to avoid design misalignment after forming.

3. No Printing on Seam Areas – Especially for spray cans, seam edges must be free of graphics or color for welding purposes.

Printing Process & Ink Requirements

Tinplate printing uses offset lithography due to its smooth, hard surface. However, inks must meet special requirements:

Varnishing for Protection and Aesthetic

After printing, tinplate is coated with varnish to enhance gloss, scratch resistance, and corrosion protection.

Types of Varnishes:

• Gloss – High shine, traditional appeal

• Matte – Paper-like, elegant texture

• Wrinkle – 3D crystal-like patterns for artistic value

• Pearlescent – Iridescent finish for luxury branding

Varnish Selection Factors: Resistance to discoloration, compatibility with base coat, flexibility, and durability.

Drying & Curing

The drying process involves:

1. Heating Zone – Raises temperature to set level

2. Holding Zone – Maintains peak temperature for curing

3. Cooling Zone – Prevents surface damage during stacking

Key Insight: Under-curing leads to weak adhesion, while over-curing causes brittleness and yellowing. Monitoring oven temperature curves is essential.

Manufacturer’s Perspective: Balancing Quality, Compliance, and Branding

From a production standpoint, custom tinplate printing is a fusion of engineering and artistry. Modern buyers demand not just protection but brand differentiation, regulatory compliance, and eco-conscious materials.

Our factory has implemented:

• BPA-free coatings for global compliance

• Energy-efficient curing systems for cost savings

• Short-run digital printing for seasonal and promotional packaging

These measures allow us to deliver flexible, high-quality tinplate solutions that align with both sustainability and branding goals.

Why This Matters for Your Packaging Strategy

Looking for a custom tinplate printing solution that blends durability, compliance, and brand appeal?

📩 Contact us today to explore tailored options for your food, beverage, or premium gift packaging needs.

💬 Which tinplate printing effect—gloss, matte, wrinkle, or pearlescent—do you think creates the strongest shelf impact in your industry? Share your thoughts below!