Spirits packaging requires closures that are reliable in high-speed lines, consistent in seal performance, and stable in appearance across batches. As a manufacturer of aluminum closure stock, we produce 3105 H18 aluminum closure sheet for spirit caps designed for roll-on pilfer proof (ROPP) caps and related closures used on glass bottles for whisky, vodka, rum, gin, and other distilled beverages.

In spirit bottling, the closure is not only a functional component. It is also part of the brand presentation and a key element in tamper evidence. These requirements place strict demands on the aluminum sheet for spirit caps, including uniform hardness for thread forming, controlled earing during deep drawing, stable surface quality for coating and printing, and tight thickness tolerance for repeatable roll-on performance.

Why 3105 H18 for Spirit Cap Closures

AA 3105 is an Al-Mn alloy widely used in closure applications due to its balance of formability, strength, and corrosion resistance. When supplied in H18 temper, it provides the rigidity and springback control typically required for cap forming and roll-on operations, especially in high output bottling lines.

From a manufacturing standpoint, 3105 H18 closure stock offers:

• Consistent mechanical response for knurling, thread forming, and pilfer band formation.

• Stable planar properties to reduce forming defects such as wrinkling and uneven skirt formation.

• Good coating and printing compatibility, especially when paired with properly treated surfaces.

• Corrosion resistance suitable for storage, transport, and humid bottling environments.

We supply this material as aluminum closure sheet, and where required, as pre-coated and printed closure stock based on the customer's forming process and cap design.

Key Advantages of 3105 H18 Aluminum Closure Sheets

1.Strength & dimensional stability
The H18 full-hard temper provides high yield strength and strong springback resistance. It is less prone to deformation during roll-on forming and capping, ensuring stable cap dimensions and reliable locking.

2.Excellent compatibility with tamper-evident designs
Suitable for ROPP and other roll-on pilfer-proof structures. The tamper-evident band forms clearly and breaks consistently, effectively preventing re-opening and re-sealing, enhancing packaging security.

3.Stable forming and processing performance
While maintaining hardness, 3105 alloy still offers a workable processing window. Blanking, curling, and roll-on forming are stable with a high pass rate, ideal for high-speed cap production lines.

4.Good corrosion resistance and alcohol resistance
The Al-Mn alloy system performs well in alcohol, beverages, and humid environments. It resists corrosion and property degradation during long-term storage, making it suitable for spirits and beverage packaging.

5.Outstanding surface quality and decorative performance
High flatness and uniform grain structure make it suitable for coating, printing, embossing, hot stamping, and other decoration processes. It delivers consistent appearance to meet mid-to-high-end branding needs.

6.Consistent sealing and reliable tightness
The high rigidity minimizes rebound after capping. Combined with liners, it maintains stable sealing over time, effectively preventing leakage and evaporation.

7.Well-balanced cost and performance
Compared with higher-strength aluminum alloys, 3105 H18 meets closure performance requirements while offering better processing efficiency and cost control.

8.Environmental sustainability
Aluminum is 100% recyclable and reusable, meeting food and beverage packaging requirements for eco-friendliness, safety, and sustainability.

Technical Specifications (Typical)

The following table lists typical supply ranges for 3105 H18 aluminum closure stock. Final values can be adjusted to customer drawings, cap type, and conversion method.

Manufacturing Capabilities

We manufacture aluminum closure stock through an integrated process route designed to ensure stable temper and surface consistency.

Rolling and temper control

• Controlled hot and cold rolling to achieve uniform gauge and mechanical response.

• Temper management for H18 delivery, ensuring repeatable hardness and forming behavior.

Slitting and sheet cutting

• Precision slitting to customer widths with controlled edge condition.

• Optional cut-to-length sheets for customers using sheet-fed stamping.

Surface treatment, coating, and printing

For customers requesting pre-coated aluminum sheet for caps or printed aluminum closure sheet, we provide:

• Surface preparation suitable for coating adhesion.

• Coil coating options based on end-use requirements.

• Printing and finish options aligned to brand and regulatory needs.

We support both standard color systems and project-based development when customers require specific appearance, chemical resistance, or processing windows.

Quality Control, Standards, and Traceability

Closure stock performance depends on consistency across coils and batches. Our quality control focuses on measurable characteristics that directly affect cap conversion and sealing.

Incoming and in-process controls

• Chemical composition verification for alloy compliance.

• Thickness measurement across width and along length.

• Flatness and shape inspection.

• Surface inspection for scratches, oil residues, and inclusions.

Coating and printing inspection (when applicable)

• Coating thickness and uniformity checks.

• Adhesion testing and cure verification.

• Visual inspection under controlled lighting for appearance consistency.

• Print registration and color consistency checks.

Documentation and traceability

• Coil ID tracking through rolling, slitting, and finishing.

• Batch records for key parameters.

• Test reports available upon request to support customer qualification.

We align supply to commonly used industrial practices and customer-specific specifications, including packaging and handling requirements for closure stock.

Customization Options for Spirit Cap Projects

Spirit brands often use differentiated cap heights, diameters, textures, and decoration. We support customization at the material level to help converters and cap manufacturers control yield and appearance.

Customization options include:

• Gauge and tolerance selection to match cap stiffness and forming margin.

• Slit widths and coil formats to suit stamping press and line efficiency.

• Surface and coating systems for corrosion resistance, printability, and liner compatibility.

• Color matching and printing support based on approved samples or color standards.

• Packaging customization such as interleaving, protective films, and pallet configurations for long-distance export.

For new projects, we recommend confirming cap design, forming route, coating system, and liner type early so we can propose the most stable closure stock configuration.

Application Scenarios and Target Industries

Our 3105 H18 aluminum closure sheet is used primarily in:

• Distilled spirits bottling: whisky, bourbon, vodka, gin, rum, tequila, brandy.

• ROPP cap manufacturing: caps with tamper-evident bands and various knurling patterns.

• Premium decorative closures: printed and coated caps for brand differentiation.

• Export-oriented packaging lines requiring stable performance across climate and logistics conditions.

Typical production environments include high-speed cap forming, lining, and bottling lines where process stability and low defect rates are essential.

Brief Comparison with Common Aluminum Materials for Bottle Caps

Conclusion: Stable Supply, Technical Support, and Long-Term Cooperation

As a manufacturing plant supplying 3105 H18 aluminum closure sheet for spirit caps, we focus on repeatable material performance, consistent surface quality, and controlled tolerances that cap producers and bottlers can rely on.

We support long-term programs with:

• Stable, batch-to-batch supply of aluminum closure stock.

• Technical coordination on gauge selection, coil format, coating systems, and forming performance.

• Project-based customization for coating and printed aluminum closure sheet requirements.

• Quality documentation and traceability to facilitate customer audits and qualification.

For your ROPP closure material needs in spirits packaging, we can review your cap drawings, forming route, and decoration targets, then propose a supply specification suitable for sustained production and export markets.