SU1750979A1 - Method for restoration of paint layer of monumental paintings work of art on the plaster - Google Patents

Abstract

Use: in the process of restoration of wall paintings, which are located in the interior of monuments with a disturbed heat and moisture regime. The invention: the paint layer of works of monumental painting on lime-sand plaster with a moisture content of up to 90% is treated with a 1-2% aqueous solution of polyhexamethylene guanidine carbonate. Dried. The polymer layer is treated with a 0.1-0.25% aqueous solution of polyacrylic acid or polyacrylonitrile hydrolyzate. Repeat treatment with 1-2% polyhexamethylene guanidine carbonate aqueous solution, 2 tab. (Ls

Description

The invention relates to methods of restoring and preserving works of monumental painting, more specifically to strengthening the pictorial surface, peeling and spraying the paint layer and located on a wet plaster base under conditions of alternate moistening and drying, and can be used in the process of restoring wall paintings found in the interior of monuments with a disturbed heat and humidity regime.

There is a method of restoration of the paint layer of works of monumental painting on plaster, including the sequential processing of the painting surface with two polymer solutions.

In order to strengthen the painting surface, which at the same time has the peeling and spraying of the paint layer, it is used to strengthen the sprayed paint layer and destructed plaster with solutions of 5 or 10% K-15/3 resin (silazanov resin; 83% solution in toluene) in white spirit or petrol galosh. The resin solution is applied with a soft brush evenly twice in 15-20 minutes. The number of impregnations depends on the state of the plaster and the paint layer. Peeling and lag of the paint layer are reinforced with an aqueous dispersion of copolymer BA-23 HA (aqueous dispersion of copolymer vinyl vinyl acetate and 2-ethyl-hexyl acrylate 52%, grade DSA-8-2-1, TU LP-133-65). Moreover, at first, the peeling of a 1-2% aqueous dispersion of BA-2EGA is strengthened, and then ras

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dusty part with K-13/3 solution of 5-10% concentration.

The closest analogue is a method of processing monumental painting on plaster, which involves applying a polymer solution to it, followed by drying and impregnating polybutyl methacrylate (PBMA). Painting, which is in a wet state, is treated by applying 15% of a 1% aqueous solution of polymethacrylic acid (PMK) in an alcohol-acetic acid mixture. After drying, the painting is impregnated with a 10% solution of PBMA in xylene.

A significant drawback of the method is the impossibility of its use in the process of emergency response work in monuments that are in conditions of a disturbed heat and moisture regime, since this method does not ensure the strengthening of the paint layer of wall paintings on a plaster base with a moisture content of more than 10%. In addition, the paint layer, reinforced by the prototype, does not possess bioproofness and is rapidly destroyed by microorganisms in the conditions of alternate wetting and drying of the plaster, which take place in a monument with a disturbed heat and humidity regime.

The purpose of the invention is to expand the technological capabilities of the method for ensuring restoration on lime-sand plaster with a moisture content of up to 90%.

This goal is achieved by the fact that in the method of restoration the paint layer of monumental painting on plaster, including processing the paint layer with a polymer solution, drying and fixing the polymer, processing the paint layer of monumental painting is carried out with a 1-2% polyhexamethyleneguanidine carbonate water solution (PHMG) , and the consolidation of the polymer is 0.1-0.25% aqueous solution of polyacrylic acid or polyacrylonitrile hydrolyzate with repetition of the treatment with a 1-2% aqueous solution of PHMG-carbonate.

An example of the conversion of hydrochloride pgmg to carbonate.

The conversion of the PHMG hydrochloride to carbonate is carried out by introducing it in the form of a 25-30% aqueous solution into a 30% solution of sodium carbonate (soda), taken in a 3-5-fold molar excess relative to the PHMG hydrochloride. The exchange reaction occurring in this case can be depicted as follows.

(CH2) 6NHCN n + nf2NQ2C03 - NH-HC1

- 1сн216мнсн п-ппмаС1

W-H2C03

The phargene carbonate formed is insoluble in a VOZ% soda solution; it floats to the surface in the form of a semi-solid mass, resembling paraffin, and can be easily separated from the solution in which the exchange reaction was carried out. It is collected from the surface, rinsed quickly with cold water and dried in vacuum at 50 ° C. The resulting brittle foamy mass is easily crushed into a powder, convenient for the preparation of aqueous solutions of different concentrations.

PRI me R 1. A portion of 100 g of PHMG-G is dissolved in 200 ml of water and added to 1 liter of 30% soda solution with vigorous stirring. Collect the emerging PHMG-K, washed from the soda solution with water (two portions of 100 ml), dried in vacuum and crushed in a mortar. By dissolving portions of 10, 15, and 20 g of PHMG-K in portions of 1 l of water each, the corresponding solutions are prepared. With concentrations of 1.1.5 and 2%, they are used during restoration work. Solutions of PAA and hypana are prepared similarly. Next, on the samples of plaster with a destroyed paint layer, a solution of 1% PHMG-K is applied by brush or spray in one or two steps until complete saturation. After 30–40 minutes, a 0.25% aqueous solution of PAA or hypan is applied with another brush or spray, ensuring the fixing of the PHMG-K layer. After another hour, a 1% solution of PHMG-K was reapplied with a brush or spray.

EXAMPLE 2: A painting that is in a wet state is processed by applying 1.5% PGMG-K in two steps until it is completely saturated. After 30-40 minutes, a 0.25% aqueous solution of PAH or heptane is applied, after one hour, a 1.5% solution of PHMG-K is reapplied with a brush or spray.

PRI me R 3. Plasma samples having both peeling and spraying of the paint layer are applied with a brush or a 2% pgmg-K spray; after 30 minutes, with a different brush, put a 0, t% water solution PAA or one hour later, a 2% solution of PHMG-K was applied.

In tab. 1 shows the results of a simultaneous investigation of the state and dissemination by the microorganisms of the paint layer after its restoration with PHMG-K with various sequences of applying polymer solutions

Table 2 compares the hardened paint layer according to the method of the invention and the prototype.

, The full effect of strengthening the peeling and sprayed paint layer, regardless of the moisture content of the plaster on which it is located, can be achieved by using impregnation with a 1-2% aqueous solution of PHMG-K and fixing it with 0.1-0.25% with a solution of polyacrylic acid or hypan. Moreover, the proposed sequence of three operations (impregnation-fixing-impregnation) allows almost completely protecting the paint layer on the lime-sandy plaster with humidity up to 90% from biofouling. azhneni and drying

Claims (1)

The method of restoration of the paint layer of works of monumental painting on plaster, including processing the paint layer with a polymer solution, drying and fixing the polymer, characterized in that, with the aim of expanding the technological capabilities of the method to enable the restoration of the paint layer on a lime-sand plaster with moisture content up to 90% with increasing conservation of the paint layer, the treatment of the latter is carried out with a 1-2% aqueous solution of polyhexamethylene guanidine-carbonate, and Polymer adhesion is carried out with 1–0.25% aqueous solution of polyacrylic acid or polyacrylonitrile hydrolyzate with repetition of treatment with a 1-2% aqueous solution of polyhexamethylene guanidine carbonate. Table 1 table 2