We have handrails/banisters in a historic building that need to be recoated prior to cleaning everyday for COVID while open. The surfaces were finished with shellac back in the 1960's but most likely never since. I've done tests on the surfaces and it appears anywhere that hands most likely touched no longer have much shellac except in the pores. The other sections where hands do not touch still retain most of the shellac applied in the 1960's.
There is shellac like I make in the lab which is a mixture of shellac flakes in denatured alcohol and there is the commercial shellac that you can buy, like Zinsser Bulls eye, that contains additives that I use at home on my own woodworking. Normally in Conservation we don't use anything that can't be easily reversible or could harm the materials involved. However in this case we may need something that will work without easily coming off either with sweaty hands or with the solution I will be using to clean against COVID which consists of a surfactant in water which will break apart the envelope that contains the virus, killing it. So whatever is used has to be able to withstand some water but not as powerful or hard to remove in the future like polyurethane.
Any ideas? I'm not as knowledgeable on modern varnishes, lacquers or shellacs as I am on other areas.
There is shellac like I make in the lab which is a mixture of shellac flakes in denatured alcohol and there is the commercial shellac that you can buy, like Zinsser Bulls eye, that contains additives that I use at home on my own woodworking. Normally in Conservation we don't use anything that can't be easily reversible or could harm the materials involved. However in this case we may need something that will work without easily coming off either with sweaty hands or with the solution I will be using to clean against COVID which consists of a surfactant in water which will break apart the envelope that contains the virus, killing it. So whatever is used has to be able to withstand some water but not as powerful or hard to remove in the future like polyurethane.
Any ideas? I'm not as knowledgeable on modern varnishes, lacquers or shellacs as I am on other areas.