29.2 New Products – a new retouching varnish, finally!


The developing of Regal Retouching Varnish is the final step of a long path begun in 2003, when CTS launched Regalrez and Laropal A81 in the Italian market. Our choice was supported by solid scientific foundations: we refer to the accurate research carried out by De La Rie [1][2], that demonstrated that low molecular weight polymers show remarkable resistance to the aging, especially when added with Tinuvin 292.

For sure we did not just rely on the findings from U.S., so we added some more tests to verify the stability of these materials even under UV radiations, considering that in Italy protection from UV is often inadequate [3][4].

The second step of the development of stable products led to the formulation of 'final varnishes' based on the aliphatic resin Regalrez 1094. In fact we launched 
Regal Varnish available in two grades: Gloss and Mat (both applicable by brush or spray).

Today, after long
 testing, we are proud to introduce and promote the new grade, extremely stable because of the urea aldehyde Laropal A81: Regal Retouching Varnish (applicable by brush or spray). It produces a colorless stable film compatible with varnish colors such as the resin binder based Maimeri and the innovative Gamblin colors made with Laropal A81.

Petroleum oil with no aromatics (boiling point range= 140-160°C) is the recommended solvent for thinning especially for spray application.

For a better opacity effect we suggest to use solvents such as ligroin having a lower boiling temperatures range.

Regal Retouching Varnish
 can be used even on porous and absorbent paintings after a preliminary application of Gustav Berger’s O.F. Isolating PVA Spray Varnish.

Because its excellent optical properties and color saturation ability and protective function 
Regal Retouching Varnish can be used as a final varnish. Further coating with Regal Varnish Gloss e Mat or other final varnishes may be adopted.


1. de la Rie E.R.; McGlinchey C.W.; "New synthetic resins for picture varnishes” e Leonard M.; "Some observations on the use and appearance of two new synthetic resins for picture varnishes”, in Cleaning, retouching and coatings, Ed. Mills & Smith, Londra (1990).
2. de la Rie E.R., Quillen Lomax S., Palmer M., Maines C.A.; An investigation of the photochemical stability of films of the urea-aldehyde resins Laropal A81 and Laropal A 101; ICOM Committee for Conservation 2002, Vol.II.
3. Borgioli L., Camaiti M.; "Stabilizzazione di polimeri per la verniciatura dei dipinti”, records of the Conference "Colore e conservazione”, Thiene (VI), 29-30
th October, 2004.
4. Borgioli L., Camaiti M., Rosi L.; "Comportamento all’irraggiamento UV di nuovi formulati polimerici per il restauro”, records of the Conference "Lo stato dell’arte 6”, Spoleto, 2-4 October