This site was updated January 2018
From my own research and study I have found there are 4 primary different mildew spores ( we Brits call it mildew, other conservators refer to it as "mould" or the US spelling "mold") that cause foxing and each reacts in a different way. The first formula I invented 17 years ago only worked on 1 spore, I tried to make a universal formula but each spore seemed to react differently and over 5 years I created 4 different formulae....one for each spore. All have one common denominator and that is they are all attracted to one single element in chemical wood pulp.
This isn't a marketable product as it is more of an exact science. You will need to be able to identify each different spore, some papers will have 2 or even 3 which means each spore will need to be treated separately......but first you will need to be able to identify many different types of paper fibres manufactured over the centuries as you will also need to identify and re-make different types and strengths of the original manufacturer's paper "size" which could be one of many different formulae used hot or cold, and this is the real key....it isn't the formulae that is important, but the method.
The mildew spores will need to be first neutralised, then removed and the paper re-sized using the original formula in manufacture....bearing in mind that if the size is too strong it will render the paper transparent....too weak will render the paper brittle, there is a fine line of 1% you cannot cross over or under........and some papers require a stronger size than others..... it isn't a straight forward operation as you may think, but a precise science...which is why there has never been a formula over the past 250 years. There was one formula in the 19thC using calcium chloride and hydrochloric acid which removed the foxing but broke down the cellulose causing cellular degradation and eventually disintegration.
All of my formulae including the removal of water stains, ink, foxing, oxidation etc...are derived from harmless plant extracts and not chemicals.....I don't manufacture or sell any of my formulae, nor have I ever patented or published papers or DVD's on them as there is no point, none of them are wipe on, wipe off products you can easily learn how to use....There are many types of mildew/mold and the 4 common to books are known as "Foxing", the spore like fungi gets its name from the (F)errous (Ox)ide or the iron it is attracted to in the paper, usually chemical wood pulp, and all are activated by the same cause...relative humidity.
Paper and leather are hygroscopic, a hygroscopic material is one that attracts moisture from the atmosphere.If not protected from contact with a damp atmosphere, books left in damp conditions will eventually disintegrate
click on images to enlarge
As you can see, we are starting to get a problem with oxidation that will cause the paper to become brittle. If the oxidation has penetrated right through the paper, chances are it will be lost.
This is not a "How To" site, you will need many years of experience in many different fields.