Mineral oil bad for leather? Or good? Or neutral?

[dikman]

SUP, I suspect you're right, the common denominator I found, when looking at the MSDS for various leather treatments, is mineral oil. It generally forms the major component in order to make the beeswax soft enough to spread as a paste. Most of the other additives are in quite small quantities, perhaps to add a pleasant smell and make people feel good because it has "natural ingredients" - although many companies consider mineral oil to be a natural product for the purpose of advertising.

Plus it's probably relatively cheap to use as a commercial component.

[SUP]

@dikman yes and along with mineral oil, other petroleum based products appear as additional ingredients as well.

About mineral oils, it is purely organic (versus inorganic) from the point of view of Chemistry. I think of it as  natural as well - the result of refining of crude oil - sources of fossil fuels. I suspect people think it is not organic because of the name - they associate the term 'mineral' with, I suppose metals and nonmetals, essentially inorganic material.  I wonder if there is another name for mineral oil.

 

 

 

[SUP]

Here are the pics and information about Lanolin, Tallow and cod liver oil. - the first row is treated with lanolin, the 2nd, with tallow and third with cod liver oil. The piece on the extreme left is untreated, for comparison.

Lanolin, tallow, cod liver oil - applied to 4 pieces each, one piece being placed in garage, outside, car and control area.

Observations as follows:

Lanolin: Immediately on application, leather pieces slightly darker than control – all remarkably consistently darkened. Smoother as well. Mild smell of lanolin.

Tallow: Immediately on application, leather pieces slightly darker than control. Smooth. No smell of tallow.

Cod liver oil: Immediately on application, leather pieces slightly darker than control. Smooth. Smell of cod liver oil.

All pieces have darkened slightly after application of test material – more or less to a similar extent. The lanolin gave the most consistent immediate darkening with the least streaking or spots. The pieces treated with tallow have no smell while those treated with lanolin and cod liver oil smell of those respective products. All the pieces feel smooth - smoother than the control. They are as soft as well but not softer than the control.

I completed this a while ago; now preparing the set with the mix of mineral oil and coconut oil.

[fredk]

Good

I'll try to get a check on my pieces tomorrow

[SUP]

I am thinking of a way to include petroleum jelly ever since your experience that it might be giving a water repellent effect.. That will be a different experiment, more to check how long the water repellent effect remains when out in the rain - its been raining here quite a bit - and then, when kept in different places, how long the effect remains. Have you had any experience with this?

[fredk]

I can tell you more tomorrow. One piece has been out in the rain since the start of March

[SUP]

I'll wait for your input.

[fredk]

Not a proper report

8 pieces have been hanging outside. It been raining a lot here, including today

All the pieces except vaseline show darkening caused by them soaking up water. The vaseline one is still as light coloured as a non-treated piece. It also show a little  of repelling water. Its lost its slickness which it had before. Other pieces also show water repelling but they are showing as having absorbed water, not a little but a lot, as much as you'd want for wet moulding

Therefore, it looks like vaseline can be water repellent or a mild waterproofer. I'd not dare venture to say it is a waterproofer

[SUP]

That's good information. I will use Vaseline on several pieces and check the extent of water absorption over hours and days.

Right now, I have applied a mixture of mineral oil and coconut oil (10%) to new leather pieces and kept them with the others.

I will prepare a new set for the Vaseline. I need to also record the thickness of the leather very specifically for each piece too, not just a generalized 5oz description.

Today, it is bright and sunny outside. Hope it rains soon.

[fredk]

7 monthly report. 26th April 2024

Pieces treated and kept on the top of the dash in the south facing  windscreen (windshield?) of a car

#1; Baby Oil;  Colour = Dark, Flex = Stiff 7/10,  Smell =  No Smell,  Other (fungus, deterioration ) = 0

#2;  Cooking Oil (rape seed); Colour = Dark,  Flex = Stiff 7/10 ,   Smell = very slightly 'leather',   Other = 0

#3;  Lard (pork fats);Colour = Light, lighter than Control #1,  Flex = Moderately stiff 5/10,  Smell =  A hint of oil,  Other = surface feels a bit 'greasy'

#4; NFO Compound; Colour = Dark, Flex is good, 4/10,  Smell = neutral, Other = 0

#5; Olive Oil;  Colour = Dark, Flex is good 3/10  Smell = very slightly of oil,  Other = 0

#6; 3-in-1 Oil;  Colour = Dark, Flex is stiff 9/10.  Smell = Slight smell of leather and a hint of oil,  Other = 0

#7; Vaseline;  Colour = Light, lighter than Control #1, Flex is stiff 6/10,,  Smell = faintly of 'leather'   Other; Surface feels very greasy

#8;  Control #1; kept with #1 to #7; Flex has stiffened, Colour = mottled light and slightly darish,  Flex = Stiff 7/10, Smell = Neutral, Other = 0  - 

Thats all for now

I'll be back soon with a report on the pieces kept outside, in rain,  sunshine and wind