IT8319893A1 - PROCEDURE FOR THE PROTECTION OF SURFACES AGAINST DEGRADATION CAUSED BY WALL WRITINGS MADE WITH PAINTS, INKS AND SIMILAR - Google Patents

Description

Description of the industrial invention entitled, "PROCEDURE FOR THE PROTECTION OF SURFACES AGAINST THE DEGREE CAUSED BY WALL WRITINGS MADE WITH PAINTS, INKS AND THE LIKE".

Summary

Prjcedimemto to prevent and / or cancel on normal materials for building and coating, the effects of degradation caused by the methods of "mural communication" made with the use of spray or brush paints, inks and the like, which consists in applying on the surface of such materials, having roughness values? less than 30 microns, and porosity? less than. 10%, a perfluoroether, as it is or in solution, having the general formula:

, or

where, P, 0, R are integers, Q and R can be equal to zero, the sum P + Q + R? between 5 and 250, M and N are integers, N pu? be equal to zero, the sum N + N? between 10 and 1000, A and l? they are perfluoroalkyl radicals containing from 1 to 3 carbon atoms.

The present invention relates to a process for avoiding or canceling the effects of degradation, which can cause us on normal building materials and coatings, from the abused methods of "wall communication" made with the use of inks, spray or brush paints, colored gypsum, posters etc.

How ? known these systems realize the communication of the pi? various messages using the useful surfaces of any building, as well as of monuments also of significant artistic interest, using different writing medium-materials such as, for example, the spraying or the brush application of paints, colored chalks or felt-tip pens, posting of printed sheets and posters etc. This phenomenon has become particularly relevant in the last decade, in urban centers and worldwide. The consequences of these "communications" are reflected not only in an aesthetic deterioration, but also in an object damage to materials, moreover of a normally irreversible, permanent nature.

To date, no useful and feasible remedies have been found, n? quotes n? curative, against these damages.

The subsequent cleaning of the soiled surfaces is usually done: a) by covering them with paint; b) in an abrasive treatment; c) in attempts to wash with solvents.

In any case, the final result of each of these treatments leads to new, clearly heterogeneous surfaces (cleaned surfaces different from the original ones, not soiled). In particular, we have that:

a) the treatment? with paint, which involves the application of a waterproof film, contravenes one of the main criteria to be adopted for the conservation-protection of stone materials and that is? the maintenance on these of the possibility? to "breathe" with the consequence of possible medium-long term damage;

bj the abrasive treatment results in a real attack of the material and, even if possible and convenient, it cannot? obviously be performed on repeated occasions;

cj cleaning with solvent leads to the soaking of the material with the solvent-paint mixture, leaving visible and permanent stains.

The economic cost of these cleaning treatments must obviously be added to these drawbacks.

Have not been identified so far "prevention" products capable, that is? to ensure repellent behavior on the protected material, towards the various products used for writing.

The process object of this invention? directed to the protection of building materials or coatings, stone and not, especially those present in closed environments, with particularly suitable surfaces / for porosity? and smoothness, upon receipt of the aforementioned products? With it you have the best results on surfaces with roughness values? RA (roughness in arithmetic mean '). Less than 30 microns, and generally between 2 and 30 microns, and porosity? lower than 10%, and in particular comprised between 0.2 and 10%.

This procedure consists in applying on the aforesaid surfaces one or more? perfluoropolyethers included in one of the following two general formulas:

or

where P, Q and R. are integers, Q and R can be equal to zero, - the sum P + Q-R? a number between 5 and 250, M and N are integers, N pu? being? equal to zero, the sum M-N? a number comprised between 10 and 1000, A and B are perfluoroalkyl radicals containing from 1 to 3 carbon atoms.

These perfluoropolyethers can be applied as such or diluted with a solvent or mixture of solvents having a boiling temperature lower than 80 ° C.

The application of these perfluoropolyethers to the surface of the material or of the manufactured article to be protected can? be carried out with any technique normally used for this purpose: with a brush, or with a compressed air gun and with a spray method. Preferably the perfluoropolyether? used diluted in a suitable chlor? fluorinated solvent that allows a better penetration of the fluid into the porosity? of the material and that has a sufficiently low boiling point to evaporate quickly after application: particularly suitable for this purpose are chlorofluorocarbons such as trichlorotrifluoroethane (Algofrene 113 of Montefluos S.p.A, Milan) - for spray pen applications and mixtures between trichlorofluoroinethane (Algofrene A 11) and dichlorodifluoromaphane (Algofre ne A 12) for spray applications?

The concentrations of the perfluoropolyether solutions to be used for this purpose can be comprised between 100% and 5% of perfluoropolyether, when the solvent? chosen from those indicated above.

quantity of perfluoropolyether which is applied per unit? surface area of the material to be protected? preferably between 50 and 200 g / m and? choice according to the porosity? of the material itself; many greater? the porosity? and so much-greater will I have to? be the quantity of protective material to be applied per unit? of surface.

The procedure is illustrated by the following examples, given only for illustrative and non-limiting purposes.

EXAMPLE 1?

Yup ? used a slab of Carrara marble whose pressed surface a porosity? of 0.3% and R value of 3.2 - 0.2. This slab has a thickness of 4, cm, with sides - 120x180 cm and? divided into two parts of equal surface on one of which? been applied uria quantity? of FOMBLIN (perfluoropolyether from Montefluos S.p.A.) equal to 80 grams / m2.

The application ? it was carried out with a brush after cleaning the surface to remove dust or external substances, with two successive operations - at intervals of about 70 h.

The surface of the plate treated with the protective 5 days after the last application appears slightly more? dark and shiny compared to the surface as it is. At this point, the following operations were performed:

a) "writing" tests, carried out by proceeding from the part of the surface as it is towards the protected surface using: 1 - spraying of red, fast drying "nitro" paint (commercial spray can);

2 ~ red paint spraying, normal, (commercial spray can);

3 - brush painting, with red paint, "nitro ?;

4 - white chalk, blackboard gods.

On the surface as it is in all cases? was evident the writing action carried out while on the protected surface ai? detected respectively:

1 - uniform trace, barely perceptible, consisting of micro drops of paint tending to coagulate;

i - as above with clots and immediate formation of large drops of paint that slide on the bottom; 3 - the brush "slips", leaving an imperceptible trail of color;

4 - the plaster "slips" without leaving any color.

b) Cleaning test. At a distance of about 30 hours from the test described in a), tests were carried out on the "written" surface. Proof ? was carried out with dry cotton cloths, soaked in acetone, and replaced with other clean ones as they were saturated with solvent varnish.

In the case of the protected surface, the removal of the retained paint? .total result, easy, quick, bringing the marble to its normal appearance. In the case of the surface as it is, the cleaning as well as being more? laborious does not achieve satisfactory results due to the persistence of evident areas of color given by the soaking of the marble with the paint-solvent solution.

Equal results; in cleaning, they are also obtained with the use of trichlorethylene, as a solvent.

EXAMPLE 2

The experience of example 1 yes? repeated using a Carrara marble with a surface having porosity? = 2% and RA = 4 0.2?, And following the same modalities? operating procedures illustrated in this example, with the difference that 100 g / m2 of FOMBLIN Y MET are applied on the surface.

Claims (3)

l) Procedure for preventing the application on building materials and coatings of paints, inks and the like, consisting in applying on the surface of such materials, having roughness values? less than 30 microns, and porosity values? less than 10%, a coating consisting of one or more? perfluo? opoliethers included in one of the following formulas or' In which I ', Q and R are integers, Q and R can be equal to zero, the sum P + Q + R? a number between 5 and 250, M and N are integers, N pu? be equal to zero, the sum M + N? a nunerr comprised between 10 and 1000, A and B are perfluoroalkyl radicels containing 1 to 3 carbon atoms. 2) Process according to claim 1, wherein the coating? applied in quantities, between 50 and 200 g / m of surface. 3) Process according to claims 1 and 2, in which the surface to be coated has roughness? between 2 and 30 microns, -and porosity? between 0.2 and 10% ..