DE300836C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

The usual protective coatings or coatings, which are attached to metal to make it more resistant to chemical agents and atmospheric influences, are usually very brittle and therefore scroll especially if the devices are temperature-. Subject to fluctuations or bumps and blows are. . .

The present invention is now a process ^10, protective coatings on metal: to give tall characterized adhesion and extensibility, that they are subjected to the application of a localized progressive mechanical treatment .: lung. According to the new. 15 processes, the protective coatings applied in the usual way on metal after "·: '■ the application (expediently after" drying) by hammering,' progressive pressing, brushing or rolling on the metal surface ■ ²⁰ solidified and at the same time in itself . ■ made stretchable. .. ..

The tension prevailing between the base body and the coating prevents the protective means used from being separated; start. Therefore, over time, all paints and the like, which are applied directly to the base body without any special post-treatment, will loosen. Something is missing . just · at the. necessary adhesion. .The best adhesives, such as 3P even armouring, .which have been used against the protective compound (paint, etc.) have failed. Only coatings which are metallically connected to the base have withstood, for example, by ³ ^ tinning in a hot bath, because there is no tension between the base and the coating. It is obvious that sufficient adhesion cannot be achieved by simply painting the protective mass. Either every air particle between the protective mass and the base body must be expelled or firmly encapsulated, or it must be encapsulated to compensate for the differences in tension The compensation body can be switched on. 45,

The former is possible by pressing by impact or sufficient local ■ lent pressure, whereby the air is completely removed, to a sucking effect to reach, or at least so far that the remaining tiny vesicles the ', Support suction.

So far, only extensible coverings and coatings made of celluloid and the like have been applied to the base body in a hot state or under-heating and heating /; ■ softness pressed over the entire surface without the structure of the ■ - '■ - covering body being changed by the surface pressure. - Even the known pressing of lacquer coatings with heating to achieve a high-gloss surface is not suitable for making the coating stretchable, resistant to impact and acid attack; In contrast, it becomes brittle and tends to form hairline cracks, which then promote flaking, apart from the fact that the hard, brittle lacquer layer cracks off in the event of impact or impact. '

Attempts have also been made to use paints as protective linings against the effects of acid on metallic apparatus in the chemical industry and the like. thereby durable to make any suitable 'matrix' applied into this in; still

Claims (1)

soft state hard materials, including powdered and grained metal brought and this was mechanically pressed into the base mass in some way, 5. in order to achieve a firm connection between the two layers. However, these aids led not -to the desired result. Nevertheless, the coating became brittle and tore when heated and sudden temperature fluctuations. kicks or flaked off during use. A completely different behavior, more brittle Coatings, in particular acid-resistant paints .- ■ 'occurs when this conforms to the new procedure '·', Appropriately post-treated, i.e. 15 'mert, locally progressively rolled on or painted. With this individual treatment of the small surface parts becomes the unevenness of the total surface of the covered body fully accounted for and. a tension equalization brought about. The coating is pressed into the finest pores, without the need for heating. The layers of air; those that hinder good adhesion are driven out completely or at least so far, that the tiny vesicles are pressed into the pores and so encapsulated suck act like the completely ventilated areas. In addition to this improved adhesion, a Push into one another and equalize the individual cross-sectional parts of the excess take place, which makes the structure of the latter so : changed, - that it becomes almost insensitive to shock and impact. This observation can be explained by the fact that each particle of the coating was already used before the relevant. Body is exposed to a very violent shock or pressure when hammering or rolling.
• Hammering or knocking is done in the simplest way with a wooden mallet. The same beneficial effect on the behavior of the coating is achieved by progressively rolling or brushing the paint on the metal body under pressure. In the case of mechanical post-treatment, it is. appropriate, first with weaker and later more pressure: to work. But you can also proceed the other way around, since the type and properties of the paint are taken into account. . . Brittleness of ^{Anstrichbelagcs:} In any case, · which is by one of the described mechanical finishing operations. lifted and not only prevented from immediately flaking, but also secured its adhesion against impact and bending. . The harmful effects of changes in the metal body (expansion or contraction) due to temperature fluctuations, as well as damage and flaking of the paint, are avoided in apparatus that are exposed to knocks and blows if, according to the invention, the finished coating, varnish and the like is mechanically stepped - j post-treated wisely. So you can z. B. 65 : ■, through suitable hammering an extremely permanent.; ■ /. · ■■ adhere, intimately connected to the apparatus ' - ', ·'"■■ After-treatment, simultaneous stretching and equalization is completely prevented.Tests have shown that even brittle coatings, which without the after-treatment soon get fine cracks and then more or less peel off after some time mechanical treatment by hammering, rolling, locally progressive pressing and the like remain constant, even allow them to bend within satisfactory limits. The coating wears out as good as -garnicht _v and protects the so-covered container at continuous use gegen'Säureangriff if it is acid resistant from the outset. All common acid-resistant paints are suitable for the new aftertreatment. So z. B. a mixture 85 / of glass powder, asbestos powder and barite 'with Bakelite varnish (phenol-Fof.maldehyd-Konden- * sationsprodukt) a good covering mass, which is exposed for the purpose of fixing and increasing the acid resistance before applying a higher temperature. As a result of this heating, the paint loses any elasticity and becomes extremely brittle, so that chipping and peeling are inevitable and the otherwise good paint is devalued. The disadvantages are eliminated immediately but when the finished painting is mechanically treated, and its durability and ■ '■' ■ durability before heating increased -.-. ' many times over. Even shock and bending then no longer cause the coating to crack or peel off. '; . '.'. ''. ' ■. ·. ■ '■ Patent claims: I. Process, protective coatings on metal, ''■;' especially acid-proof, to make stretchable; and to prevent peeling, characterized in that the paint _; / after the application of a locally progressive mechanical machining treatment ^ 110; : .- ■: lung (knocking, pressing, stroking, rolling zen or the like) is subjected. '2. embodiment of the method according to claim i, characterized in that _; ; ■ initially. a light, then a stronger, locally progressive mechanical post -'.-..'.- ■ ·: "treatment of the protective coating or" vice versa is carried out. ■■■■ '■ Λ