Claims
- 1. A process for adhering rubber to an aluminum surface, comprising the steps of:
- anodizing the surface of the aluminum which is to be adhered to the rubber;
- treating said anodized surface with a solution consisting essentially of a silane mercaptan in an organic solvent;
- causing substantially total evaporation of said organic solvent; and
- subsequently, depositing said rubber directly on said silane mercaptan treated surface and maintaining at a temperature of about 200.degree.-250.degree. C. for at least two minutes without application of pressure to adhere said rubber to said aluminum surface.
- 2. A process according to claim 1, wherein the aluminum surface is first degreased and then pickled with soda, prior to anodizing.
- 3. A process according to claim 1, comprising anodizing to develop a film of oxide of a thickness of between 2 and 5 .mu.m.
- 4. A process according to claim 1, wherein the silane mercaptan is of the general formula HS (CH.sub.2).sub.n --Si--(OR.sub.1).sub.3 in which n is equal to 2 or 3 and R.sub.1 is an alkyl group having from 1 to 4 carbon atoms.
- 5. A process according to claim 4 wherein the formula of the silane mercaptan is HS(CH.sub.2).sub.3 --Si--(OCH.sub.3).sub.3.
- 6. A process according to claim 1, wherein the proportion of silane in the solvent is between 1 and 5% by weight.
- 7. A process according to claim 1, wherein the treatment with the solution of silane mercaptan is effected by spraying said solution onto the surface of the aluminum.
- 8. A process according to claim 1, wherein the treatment with the solution of silane mercaptan is effected by dipping into a bath of said solution.
- 9. A process according to claim 1, wherein the evaporation operation is carried out in the vicinity of 100.degree. C. for the period of time required to cause complete evaporation of the solvent.
Priority Claims (1)
| Number |
Date |
Country |
Kind |
| 88 08476 |
Jun 1988 |
FRX |
|
Parent Case Info
This invention relates to a process for sticking rubber to aluminium.
Hereinafter the term aluminium is used to denote the element itself with its usual impurities as well as alloys thereof while the term rubber is used to denote natural rubber, vulcanisable synthetic rubbers and mixtures thereof. Those products may occur in the form of thin sheets, strips, slabs and moulded parts of any thickness.
The application of rubber to a metal substrate such as aluminium or the reverse is well known in many areas in industry. It is used for example for producing solid tires for wheels, sound-proofing strips, vibration insulators, coatings for reservoirs or cylinders for offset printing, slides for automobile windows, magnetised blocks for closing doors, etc.
The attraction of such an application arises out of the fact that the composite material which results therefrom has both the mechanical strength properties of metal and the elastic and/or chemical inertia properties of rubber.
However, in order for the composite material fully to develop the above-mentioned properties, the components thereof must bond perfectly to each other and that bond must be maintained with the passage of time, irrespective of the severity of the stresses to which it is subjected in use thereof, such as: substantial tensile, compression and shearing forces, elevated temperature, rapid thermal cycles of large magnitude, humid and corrosive media, etc. That is one of the major problems with which the manufacturers of such composite materials are faced.
It is true to say that solutions have been put forward hitherto. Mention may be made for example of the use of a commercially available product bearing the mark "CHEMOSIL", being a kind of lacquer which is deposited at the surface of the aluminium by spraying and then baked for 3 minutes at 200.degree. C. and 4 to 5 minutes at 160.degree. C., those operations being repeated to give a film which is approximately 5 .mu.m in thickness to which the rubber is then applied. Besides its relatively high cost, that product suffers from the disadvantage of emitting noxious vapours when it is handled and baked and causing difficulties and discomfort in certain workshops for the operating personnel.
Being aware of those disadvantages and wishing to find a simple solution to the problem of sticking rubber to aluminium which makes it possible for the interface of the components to be maintained unchanged irrespective of the severity of the stresses to which the composite materials produced are subjected, the applicants sought and developed a process which is characterised in that the surface of the aluminium which is intended to be brought into contact with the rubber is anodised in a sulphuric medium and then treated with a solution of silane mercaptan in an organic solvent and then dried and applied in the hot condition to the rubber.
US Referenced Citations (10)
Patent Grant
4988401
