Mill finish
Plain, clean strip for caps that are lacquered or anodised after forming, or used bare.
Pharmaceutical closure guide
1060 O and H22 Aluminium Strip and Foil for Vial Seals
Vial seal makers use 1060 aluminium strip, around 0.15 – 0.5 mm thick, in soft O or lightly hardened H22 temper, to draw the crimp caps that hold rubber stoppers on injection vials. The alloy must draw without splitting, crimp tightly, show low earing and carry lacquer or colour cleanly. This guide covers the specification points that decide whether strip runs well on a seal line.
- Alloy
- 1060 (≥ 99.60 % Al)
- Tempers
- O · H22
- Thickness
- 0.15 – 0.50 mm
- Earing
- ≤ 6 % (O), ≤ 5 % (H22)
Why 1060 is used for vial seals
An aluminium vial seal (crimp cap) is a shallow drawn cup that is pressed over the rubber stopper of an injection vial and rolled under the vial lip. It holds the stopper in place and provides tamper evidence; flip-off versions add a plastic button that is snapped away before use.
Making that cup and crimping it puts specific demands on the strip. It must draw in one or two strokes without tearing, so ductility and a fine, even grain matter. The cup rim must be level, so the strip must have low earing (the wavy rim caused by directional properties). It must crimp tightly without cracking on the vial lip, and tear-off scores must open with a predictable force. 1060, at 99.6 % aluminium, offers very high ductility and clean surfaces for lacquering, which is why it is widely used for these caps alongside 8011 and 3xxx alloys.
Dimensional requirements for aluminium caps for injection vials are set by ISO 8362-3 and, for aluminium-plastic combination caps, ISO 8362-6; the cap maker works from those, and the strip specification follows from the cap design.
Specification of 1060 vial seal strip
| Item | O temper | H22 temper |
|---|---|---|
| Thickness | 0.150 – 0.500 mm | 0.400 – 0.500 mm |
| Width (strip and foil) | 50 – 1,500 mm | 50 – 1,500 mm |
| Sheet size | Width 500 – 1,500 mm, length 500 – 2,000 mm | As O |
| Coil inner diameter | 75, 150, 200, 300, 350, 405 or 505 mm | As O |
| Tensile strength | 55 – 95 MPa | 75 – 110 MPa |
| Elongation, min. | 15 % (0.15 – 0.32 mm), 18 % (over 0.32 mm) | 6 % |
| Earing, max. | 6 % | 5 % |
Typical supply values for vial seal strip. Earing is measured by a cupping test such as EN 1669; tensile values per the order specification and mill certificate.
The thinnest O-temper strip, about 0.15 – 0.22 mm, is used for standard 13 mm and 20 mm crimp seals. H22 at 0.4 – 0.5 mm suits larger or stiffer caps where the extra strength helps the cap keep its shape and resist handling damage.
Thickness, width and flatness tolerances
| Parameter | Range | Typical limit |
|---|---|---|
| Thickness tolerance | 0.150 – 0.250 mm | ± 0.005 mm |
| Thickness tolerance | 0.250 – 0.500 mm | ± 0.010 mm |
| Width tolerance | Up to 800 mm | +0.5 / 0 mm |
| Width tolerance | Over 800 mm | +1.0 / 0 mm |
| Longitudinal flatness | 0.150 – 0.250 mm | Wave height ≤ 2.0 mm, ≤ 4 waves per metre |
| Longitudinal flatness | 0.250 – 0.500 mm | Wave height ≤ 3.0 mm, ≤ 3 waves per metre |
| Transverse flatness | All | Wave height ≤ 1.5 mm, ≤ 2 waves per metre |
| Camber / coil telescoping | Strip | ≤ 5.0 mm / ≤ 1.0 mm |
Thickness consistency matters most. A cap press is set for one gauge; strip that varies changes the drawn height, the crimp and the force needed to remove the tear-off. Tight thickness tolerance, flat strip and straight edges let the press run fast with fewer stoppages.
Surface finishes and lacquers
Lubricated (DOS oil)
A light, even film of food- and pharma-compatible lubricant that helps drawing.
Chromate-free or chromated pretreatment
A conversion layer that improves lacquer adhesion. Many buyers now require chromium-free systems.
Colour lacquer one side
Gold, silver, white, red, blue, green, black and other colours for product and dose coding, with a protective lacquer on the reverse.
Clear lacquer both sides
Protects the metal and gives a bright appearance while allowing printing.
Lacquers on closures that touch the stopper, or that are used in medicine packaging, must meet the regulatory requirements of the target market. Ask for a declaration of compliance for the lacquer system along with the material certificate.
1060 chemical composition (wt %)
| Element | Limit |
|---|---|
| Aluminium (Al) | ≥ 99.60 |
| Silicon (Si) | ≤ 0.25 |
| Iron (Fe) | ≤ 0.35 |
| Copper (Cu) | ≤ 0.05 |
| Manganese (Mn) | ≤ 0.03 |
| Magnesium (Mg) | ≤ 0.03 |
| Zinc (Zn) | ≤ 0.05 |
| Titanium (Ti) | ≤ 0.03 |
| Vanadium (V) | ≤ 0.05 |
| Others, each | ≤ 0.03 |
Aluminum Association registered limits, equivalent to EN AW-1060 in EN 573-3.
Seal and cap designs made from 1060 strip
- Plain crimp seals with a centre hole exposing the stopper for needle access
- Flip-off seals with a plastic button over the centre
- Tear-off seals: centre tear-off, double tear-off, scoreline tear-off and universal tear-off designs
- Bridge seals, where a scored bridge is lifted to reveal the stopper
- Pull-off and full tear-off caps for infusion bottles and diagnostic vials
Scored designs need consistent temper and thickness, because the opening force depends on the residual metal under the score. If opening forces vary between lots, check thickness and tensile strength first.
What to specify when buying vial seal strip
- Material1060, temper O or H22, thickness and tolerance, width and coil ID.
- Forming propertiesTensile range, minimum elongation and maximum earing with the test method.
- SurfaceFinish, lacquer type and colour, coating weight, and compliance declarations.
- QualityFlatness, camber, pinhole and surface-defect limits; EN 10204 3.1 certificate.
- PackingCoils on pallets, eye-to-sky or eye-to-wall, sealed against moisture with desiccant for sea freight.
References and standards
- ISO 8362-3 – Injection containers and accessories: aluminium caps for injection vials
- ISO 8362-6 – Injection containers and accessories: caps made of aluminium-plastics combinations for injection vials
- EN 1669 – Aluminium and aluminium alloys, test methods: earing test for sheet and strip
- EN 573-3 – Chemical composition and form of wrought products
- ISO 7271 – Aluminium and aluminium alloys: foils, dimensional tolerances
Vial seal strip: frequently asked questions
Why is low earing important for vial seals?
Earing makes the rim of a drawn cup wavy. Uneven rims crimp unevenly under the vial lip, which can leave gaps or cause rejects on inspection, so seal makers set a maximum, commonly 5 – 6 %.
What thickness of aluminium is used for vial seals?
Most standard 13 mm and 20 mm crimp seals use about 0.18 – 0.22 mm strip. Heavier caps use up to about 0.5 mm.
Should I choose O or H22 temper?
O temper is softest and draws most easily, so it suits thin strip and deep caps. H22 is slightly stronger and stiffer, which helps larger caps keep their shape.
Is 1060 or 8011 aluminum better for vial caps?
Both are used. 1060 is more ductile and lacquers very cleanly; 8011 is a little stronger. The choice depends on the cap design, press tooling and customer approvals.
Can the strip be supplied lacquered and coloured?
Yes. Metline supplies vial seal strip mill finish, lubricated, pretreated, clear-lacquered or colour-lacquered to your colour code, with material certificates.
Sourcing strip for vial seals?
Send the temper, thickness, width, coil ID, lacquer and quantity. We will confirm availability and a delivered price.
