We manufacture leather gun holsters and they are clear coated for the final finish.As a test I have tried to oil some of them after the clear coat. The oil does soak in, not evenly but it does get in .I have left them 15hrs to find a spoted light and dark holster in the morning.We are talking about 9oz leather, cars are maybe 4 oz. Now there are many different kinds of leather and clear coat available.This info is just IMO and testing that I have done. But if you left it, whatever you are using{if it has some type of oil in it} on your seats for a long time it will soak thru the clear coat and not evenly.If you just did a quick on and off with an oil based product, you are most likly just wearing down the clear coat,depending on what chemicals you are using.There are things written on leather conditioners that IMO aren't true.Some leather oil is very aggressive. The problem we face is you give a tannery that produces leather spec's{hard temper, soft temper,has to mold and take a shape, 8oz,4oz,2oz,from the shoulder, from the belly,from the side, ect,ect} on what you need the leather to do and they will produce the leather to those specs. Not all car companys do the same thing. So depending on what was done to the leather at the tannery ,to get it the way you need it, to manufacture a product, has alot to do with how it will react to chemicals being put on it. I have had bad leather where the tannery did something wrong and the salts and chemicals they used were coming to the surface of the leather. I could not even dye black over it .The leather just kept ozing white stuff.The reason we oil the holsters or any leather is to replace the natural oils that were once present before the tannery manufacture and our manufacture process.We beat the heck out of it to get it to do what we need it to do.Thats why some leather cracks , cause its missing the natural oils it once had.Car leather takes a great amount of abuse with the different temps and the sun beating on it. I am wondering if the car leather could be reclear coated. There are sprays on the leather goods market that will do this. HMMMM Anybody out there want to do a test, I will give you a supplier of clear coat for leather or go right back to the car company maybe they will let you know what they use. I would do it but I can't, I do not have leather in my cars. Anyway I hope I helped and again ,this is just my testing on the leather,oil,clear coat,dye ect ect, I use to manufacture with.
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