Saturday, December 4, 2021

Painting Art - Part IV
Art Resource

Marie-Therese Wisniowski

Preamble
This is the fifth post in a new Art Resource series that specifically focuses on techniques used in creating artworks. For your convenience I have listed all the posts in this new series below:
Drawing Art
Painting Art - Part I
Painting Art - Part II
Painting Art - Part III
Painting Art - Part IV
Painting Art - Part V
Painting Art - Part VI
Home-Made Painting Art Materials
Quality in Ready-Made Artists' Supplies - Part I
Quality in Ready-Made Artists' Supplies - Part II
Quality in Ready-Made Artists' Supplies - Part III
Historical Notes on Art - Part I
Historical Notes on Art - Part II
Historical Notes on Art - Part III
Historical Notes on Art - Part IV
Historical Notes on Art - Part V
Tempera Painting
Oil Painting - Part I
Oil Painting - Part II
Oil Painting - Part III
Oil Painting - Part IV
Oil Painting - Part V
Oil Painting - Part VI
Pigments
Classification of Pigments - Part I
Classification of Pigments - Part II
Classification of Pigments - Part III
Pigments for Oil Painting
Pigments for Water Color
Pigments for Tempera Painting
Pigments for Pastel
Japanese Pigments

There have been one hundred and thirteen posts in a previous Art Resource series that focused on the following topics:
(i) Units used in dyeing and printing of fabrics.
(ii) Occupational, health & safety issues in an art studio.
(iii) Color theories and color schemes.
(iv) Optical properties of fiber materials.
(v) General properties of fiber polymers and fibers - Part I to Part V.
(vi) Protein fibers.
(vii) Natural and man-made cellulosic fibers.
(viii) Fiber blends and melt spun fibers.
(ix) Fabric construction.
(x) Techniques and woven fibers.
(xi) Basic and figured weaves.
(xii) Pile, woven and knot pile fabrics.
(xiii) Napped fabrics, double cloth and multicomponent fabrics.
(xiv) Fabric finishes.
(xv) Schrinkage, durable press and wash-wear finishes.
(xvi) Classification of dyes and dye blends.
(xvii) The general theory of printing.

To access any of the above resources click on the following link - Units Used in Dyeing and Printing of Fabrics. This link highlights the one hundred and thirteen posts in the previous Art Resource series.

There are eight data bases on this blogspot, namely: (1) the Glossary of Cultural and Architectural Terms; (2) Timelines of Fabrics, Dyes and Other Stuff; (3) A Fashion Data Base; (4) the Glossary of Colors, Dyes, Inks, Pigments and Resins; (5) the Glossary of Fabrics, Fibers, Finishes, Garments and Yarns; (6) Glossary of Art, Artists, Art Motifs and Art Movements; (7) Glossary of Paper, Photography, Printing, Prints and Publication Terms; (8) Glossary of Scientific Terms.
Note: From time-to-time all the above data bases will be updated.

If you find any post on this blog site useful, you can save it or copy and paste it into your own "Word" document for your future reference. For example, Safari allows you to save a post (e.g., click on "File", click on "Print" and release, click on "PDF" and then click on "Save As" and release - and a PDF should appear where you have stored it). Safari also allows you to mail a post to a friend (e.g., click on "File", and then point cursor to "Mail Contents On This Page" and release). Either way, this or any of the other posts on this site may be a useful Art Resource for you.

The new Art Resource series will be the first post in each calendar month. Remember, these Art Resource posts span information that will be useful for a home hobbyist to that required by a final year University Fine-Art student. Undoubtedly, some parts of any Art Resource post may appear far too technical for your needs (skip those mind boggling parts) and whilst other parts may be too simplistic with respect to your level of knowledge (ditto the skip). Hopefully, the trade-off between these two extremes will mean that the Art Resource posts will be useful in parts to most, but unfortunately, may not be satisfying to all!


Painting Art - Part IV[1]
Fresh Paint

A common cause of a simple lack of cohesion lies in the use of paint from which some or most of its adherent or glueing-on power has been lost. When the usual coating material begins to dry on exposure to air, it passes through a sticky, tacky or viscous stage, after which it jells and then becomes solid. If the paint passes through this entire viscous stage while it is in contact with the ground it will adhere. If it has already passed into this stage before application to the painting, it obviously cannot be expected to perform so well.

Perfect coating adhesion
Perfect coating adhesion.

Paints such as oil, egg tempera, casein and ethyl silicate, whose binding actions are due to chemical reactions, will always lose adhesive power to some degree if they are allowed to enter the adherent stage before they get put where they belong, on the canvas, panel or wall.

Egg tempera recipe
Egg tempera recipe.

In the case of a fresco, where the wall plays the adhesive role, this principle is accepted as an unquestionable part of the technique; no fresco painter will attempt to apply further strokes after the fresh cementitious character of the surface begins to pass and the wall ceases to imbibe the color.

The anatomy of a fresco
The anatomy of a fresco.

Some other coatings, for example water colors, gouache paints, and simple solution varnishes such as pure damar, dry by simple evaporation of their solvents and so do not come under the restriction of this observation, for no chemical change is involved and they can be reconditioned so that they will go through the tacky stage once more. Water color and gouache can usually be remoistened or ground in water; more turpentine may be added to thickened damar.

Damar resin
Damar resin.

Another exception is encaustic color, which remains perennially thermoplastic; the difference between the fluid color and the solid painting is solely one of temperature. But no amount of thinner will reverse the oxidation or polymerization of oils or the denaturing of proteins. Technologists classify the film-formers into two groups: thermoplastic or convertible. The former remains unchanged on drying, the latter undergoes an irreversible reaction and becomes a new substance. The term thermoplastic is here used in a somewhat different sense from its general meaning.

Mechanism of aqueous polymer film formation process
Mechanism of aqueous polymer film formation process.

Larger volumes of paints, varnishes, and enamels such as fluid materials in cans, where a thin skin has been formed on the surface on short aging, particularly when a volatile solvent is present, may frequently be utilized by the removal of skin and, if necessary replacement of the evaporated solvent.

Refreshing old paint
Refreshing old paint.

However, the relatively small volumes or dabs of tube paint aged on a palette are more likely to have become affected throughout the mass, even when the interior seems more fluid than the outer crust. According to this principle, on the resumption of painting from a palette that was laid aside, only those oil colors which appear as soft as those fresh from the tube are worth taking chances on, and those which would require thinning to use, should be discarded.

Paint aged on a palette
Paint aged on a palette.


Reference:
[1] The Artist's Handbook of Materials and Techniques, R. Mayer, (ed. E. Smith) 4th Edition, Faber and Faber, London (1981).

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