Chemical Release of Metal Coating

[WASHuSTL]

I know that Gold is a tried and true option for a nice "release" of the gold metal coating from glass or most metals. What is the property of Gold that makes it a good option? I really hope that there is a cheaper option with similair "chemical release properties."

 

Thanks very much for any help. I have spent considerable time google monkeying this, but that and my chemistry 101 background are failing me.

[YT2095]

never heard of such a term???, define "release" and/or at least the properties of it.

[WASHuSTL]

Rough description, bare with me- A thin film of gold seperates nicely as a sheet from a flat surface. Tape, epoxy, or any adhesive can lift the layer of Gold from a sheet of glass.

 

Another way to put it- Gold is the opposite of chrome in this respect as chrome adheres strongly to anything.

 

If someone can answer your question of what I am actually asking for- then I think I am home free. So to rephrase my question- why, chemically, does gold nicely "sheet" off of flat surfaces such as glass or most metals.

 

Thanks.

[insane_alien]

ahh right, well, gold is softer than glass so it cannot scratch glass. but it can scratch more gold so you could use it to scrape gold off glass without damaging the glass. as for a chemical method, anything that dissolves gold but leaves glass alone would do,

[pioneer]

Gold has an almost a perfect balance between the proton's in the nucleus and the electrons in its orbitals, which makes gold very inert. It has little chemical affinity for materials like glass.

 

Gold is also the most malleable element, able to be beaten thinner than a hair. This property is connected to the inert nature of gold. Gold is so stable, it has little need to lower energy further by forming large crystals. This allows us to beat the gold thinning and thinner before fracture. Usually, we tear it, since it is not very strong due to the moderately weak bonding between the atoms in metallic gold. It is a very soft metal.

 

One way to simulate gold leaf, is to use fine metal powders within acrylic suspensions. (Metal Affects Paints by Modern Masters Co.). Basically spray paint, a thin 1-2ml coat on teflon, HDPE or glass and then peal it off. You can make complex cutout shapes using masking tape and an exacto-knife. A little heat from a hairdrier can to make it easier to pell off.

 

If you wish to decorate a say a glass with a gold rim, mask off the design. Use a thin coat of a bonding primer to stick to the glass and then spray the metal. Some of these metal paints are reactive metals, that allow you to create the look of tarnished copper, rust, etc. This is done using an acid solution that promote rapid oxidation. One can make a new vase look like it has been sitting the ground for centuries. I hope that is what you had in mind at a fraction of the cost of using gold.

[John Cuthber]

Pioneer is talking nonsense saying "Gold has an almost a perfect balance between the proton's in the nucleus and the electrons in its orbitals, which makes gold very inert.".

Every metal has exactly the same number of electrons round the nucleus as protons in it. Sodium for example has 11 protons and 11 electrons. It is hardly inert.

 

I think the essence of the reason is very simple. Gold is soft so it can be peeled off easily and it's generally pretty inert so it doesn't bond to substrates like glass.

 

IIRC silicone grease is also used for this sort of thing but it clearly depends on the context.

What are you hoping to release from what?