DE1432270A1 - Disposable containers, in particular tin cans, made of aluminum - Google Patents

Description

It is disposable containers, especially food cans, made of aluminum known to produce disposable containers, especially food cans, from aluminum0 With certain filling goods such as fruit juices, vegetables, sour herrings, dairy products etc0, however, corrosion attack on the aluminum must be expected to local erosion and possibly to perforations in the sometimes very small ones Wall thickness can lead.

Off serve. Basically, cans and other transportable containers are used Made of aluminum usually protected against corrosion on the inside, which is e.g. B. can be achieved by a layer of paint. To increase the resistance, especially the adhesive strength of the paint film, the aluminum surface is facing after painting either anodically oxidized or provided with a primer. These Primers often contain substances that are harmful to health, such as B. Chromates, so that there are concerns about their use in food.

Since it is technically difficult, the inner surface of such containers to provide a sufficiently uniform surface protection that is flawless Corrosion protection guaranteed, is z. B. in the production of cans proceeded in such a way that the aluminum sheets or strips have already been surface-treated be, but this has the disadvantage that the oxide layer bss. the paint layer the shaping work by pulling, pressing, punching, etc., tears or otherwise is damaged, whereby the anti-corrosive effect is questioned. Cracks in the oxide layer and / or ii lacquer film can also occur due to the transport Impact loads arise.

According to the invention, for the production of disposable containers, In particular, tin cans, sheets or strips made of aluminum or aluminum alloys used, plated with aluminum or aluminum alloys in a known manner are, the plating being less noble than the to plating material and consequently has an electrochemical protective effect on it. this can be made by suitable choice of the chemical composition of the plating and the to be clad material can be achieved. For the plating, for example Pure aluminum or an aluminum alloy with alloy additives used that cause a ignoble behavior, while the material to be clad components its potential compared to the plating - the more noble one - are added Move page. An additional surface protection through anodic oxidation or painting is unnecessary, as there is a possible corrosion attack on one Experience has shown that composite material clad in this way is relatively thin Plating layer limited and can not extend over to the clad material. As a result, a one that extends over the entire wall thickness is made in a simple manner The invention is intended to be based on the following exemplary embodiment to be discribed.

It is based on a 0.5 mm thick sheet made of an aluminum alloy with about 1 ffi Mn, which is clad on one side with pure aluminum (Al 99.5).

This sheet metal is used in a known manner to make a tin of about 100 mm in diameter and 150 mm in height, with the cladding layer being the inside forms. The connection of the sheet metal end in the manufacture of the can jacket as well the attachment of the can bottom and lid can be known by folding or other methods Way.

To the electrochemical protective effect of the clad layer in the event a corrosion attack can de Alkn alloy copper content and Mg contents or Zn contents up to t ffi or higher are added to the cladding material will.

It is basically possible to have the plating not only on one side, but also to be applied on both sides, with the chemical composition of the inner and outer clad layer may be different.

Finally, according to the invention, tin cans made of clad can also be used and unplated parts. So z. B. for the coat and alken for the cover and / or bottom clad material of the type described used werden0 The most appropriate combination depends on the respective purpose. Which chemical composition for the cladding layer and the material to be clad is used depends on the vulnerability of the product and can be caused by corrosion tests be determined.

Claims (1)

Claims 1) Disposable containers, in particular food cans, from Aluminum, characterized in that it is made from clad sheets or strips getting produced. that 2) disposable container according to claim 1, characterized in that by suitable choice of the chemical composition of the clad layer and the to be plated material is exerted an electrochemical protective effect by which restricts corrosion to the clad layer. 3) Disposable container according to claim 1 and 2, characterized in that for plating pure aluminum or aluminum alloys with added magnesium, Zinc or other components can be used to make the cladding layer more resistant Give behavior towards the material to be clad. 4) Disposable container according to claim 1 - 3, characterized in that for the material to be clad, pure aluminum or aluminum alloys with additives of manganese, copper or other components are used related to the to be plated Give the material a more noble behavior compared to the clad layer. 5) Disposable container according to claim 1 - 4, characterized in that only materials clad on one side are used, the cladding layer of which is the Forms inside of the container. 6) Disposable container according to claim 1 - 4, characterized in that the sheets and strips used are clad on both sides. 7) Disposable container according to claim 6, characterized in that the chemical composition of the inner and outer cladding is different, 8th) Disposable container according to claims 1-7, characterized in that only certain parts of the container (shell, lid or base) are made of clad materials, while the other parts are unplated0 9) Disposable container according to claims 1-7, characterized in that only the cover and / or base are made of clad aluminum consist, while the side panels are made of tinplate, plastic, paper or the like made beef,