Preamble
This is the fourtieth 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
Pigments for Fresco Painting - Part I
Pigments for Fresco Painting - Part II
Selected Fresco Palette for Permanent Frescoes
Properties of Pigments in Common Use
Blue Pigments - Part I
Blue Pigments - Part II
Blue Pigments - Part III
There have been another one hundred and thirteen posts in a previous Art Resource series that have 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) Durable press and wash-and-wear finishes;
(xvi) Classification of dyes and dye blends;
(xv) The general theory of printing.
To access any of the above resources, please click on the following link - Units Used in Dyeing and Printing of Fabrics. This link will highlight all of the one hundred and thirteen posts in the previous a are eight data bases on this blogspot, namely, the Glossary of Cultural and Architectural Terms, Timelines of Fabrics, Dyes and Other Stuff, A Fashion Data Base, the Glossary of Colors, Dyes, Inks, Pigments and Resins, the Glossary of Fabrics, Fibers, Finishes, Garments and Yarns, Glossary of Art, Artists, Art Motifs and Art Movements, Glossary of Paper, Photography, Printing, Prints and Publication Terms and the Glossary of Scientific Terms. All data bases in the future will be updated from time-to-time.
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 (click on "File", and then point cursor to "Mail Contents On This Page" and release). Either way, this or 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 and so undoubtedly, some parts of any Art Resource post may appear far too technical for your needs (skip those mind boggling parts) and in other parts, it may be too simplistic with respect to your level of knowledge (ditto the skip). The trade-off between these two extremes will mean that Art Resource posts will be hopefully useful in parts to most, but unfortunately may not be satisfying to all!
White Pigments - Part II [1]
Zinc White
Zinc White a term peculiar to the artists' material trade, where it is intended to describe Zinc Oxide of the highest degree of purity.
Zinc White.
The manufacture and sale of artists' colors is an insignificant branch of the color industry, and other white pigments, such as lithophone, contain zinc, and in the past, because of the disorganized system of nomenclature, were frequently sold as Zinc White. The best grades of domestic dry Zinc Oxide are sold under the trade name of Florence French Process Zinc Oxides. There are three varieties, all of which are more than 99% pure, and any one of which may be identified as such, as the differences between them are not great.
Zinc Oxide.
White Seal is the finest-grained and fluffiest; Green Seal is just white, but denser and less bulky; Red Seal is slightly inferior in whiteness and fineness of grain to the others. A grade of still higher chemical purity is also available under the name of B.P. Zinc Oxide, but this is made for pharmaceutical preparations and so has inferior paint pigment's or physical properties. White Seal is generally best suited for artists' paints.
Green Seal (Zinc Oxide).
Zinc White, as a paint, is free from the two defects of Flake White. It is not poisonous, and since Zinc Sulphide is white, any action that sulphur fumes might have on Zinc Oxide in a painting, will not alter its color. Flake White in oil is adequately white, as is evidenced by its brilliant effects on many old paintings, when they are in good, clean condition, but Zinc is still whiter. If Flake White is called Milk White, then Zinc could be called Snow-White. In oil, it has a harsher, colder or bluer effect, and is very much less opaque. It is employed in oil only where its lack of great opacity is either desirable or of no detriment; if a more opaque white is required, Flake White or a mixture of 50% titanium with Zinc White is used.
Flake White.
Zinc White is a reactive pigment oil (see a future post in this series). It unites, but not in the same way, as Flake White does. It tends to make brittle, hard films in comparison with tough, flexible films of White Lead. Its film has none of the desirable paint qualities described under the term, 'Flake White.' It brushes out poorly, and it is an exceptionally bad drier. Its particle structure is rather finer than that of the average pigment. Poppy oil films are definitely less permanent with Zinc than with Flake White.
Zinc White in Powders and in Linseed Oil (as viewed under a microscope).
Under severe weathering conditions, such as those to which an outside painted house are subjected (and which may be taken, in a measure, as accelerated or exaggerated indications of the conditions an artistic painting may undergo over a long period of years), White Lead films decay by becoming soft and powdery, whereas in the case of zinc films, they become brittle, and cracking and flacking are evident; in the average climate, mixtures of the two, containing not more than 60% of either, are more resistant to decay than is Zinc or Lead alone. An addition of 10% of Blanc Fixe, increases durability of such outdoor paints, evidently by reinforcing the structural strength of the film.
Signs of a worn-out house paint of Zinc White.
Although Zinc Oxide is a very slow drier in linseed oil, and remains rather soft and flexible for some time, the oxidation of the oil is merely retarded; the drying action will continue until the film has reached its characteristic hard brittle condition. Hence, Zinc Oxide, is not as good as Flake White or Cremnitz White for use in underpaintings; it is liable to be the cause of cracking, on account of shrinkage in volume, accompanying the slow drying of the film. The danger is increased by its finely divided particle size, and it is more likely to take place when poppy oil is used. In general, Zinc White, especially when ground in poppy oil, may be considered of greatest value as a top coat, or in simple, direct, one-sitting painting.
Study of the impact of different levels of zinc on the yellowing of Titanium and Lead Whites after 2.5 years of indoor aging.
In all aqueous medium, Zinc White is free from defects and gives very good results. It has long been used as a water color under the name of Chinese White, and when thus employed, its opacity is usually satisfactory. Where has not sufficient hiding power, as in work done for photographic reproduction, titanium should be subsituted for it.
Lithopone
Lithopone is used for interior wall paints, in enormous quantities, but despite its modern improvements made in its properties, it is universally condemned as an artists' white. In oil paints it is considerably inferior in color and color stability to Zinc Oxide. However, it has good opacity, and its structural or film-forming properties are excellent; therefore, it is generally considered acceptable for use in grounds, either in water or in oil mixtures. Its fineness of grain may cause trouble when used with poppy oil. Lithopone has a structural advantage over Zinc Oxide in oil grounds and underpaintings, namely because its films tend to dry more completely and thoroughly within a comparatively short timeframe, and moreover, to be less brittle.
Lithopone, C.I. Pigment White 5, is a mixture of inorganic compounds, widely used as a white pigment powder. It is composed of a mixture of barium sulfate and zinc sulfide. These insoluble compounds blend well with organic compounds, and confer opacity.
Reference:
[1] The Artist's Handbook of Materials and Techniques, R. Mayer (ed. E. Smith) 4th Edition, Faber and Faber, London (1981).
This is the fourtieth 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
Pigments for Fresco Painting - Part I
Pigments for Fresco Painting - Part II
Selected Fresco Palette for Permanent Frescoes
Properties of Pigments in Common Use
Blue Pigments - Part I
Blue Pigments - Part II
Blue Pigments - Part III
There have been another one hundred and thirteen posts in a previous Art Resource series that have 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) Durable press and wash-and-wear finishes;
(xvi) Classification of dyes and dye blends;
(xv) The general theory of printing.
To access any of the above resources, please click on the following link - Units Used in Dyeing and Printing of Fabrics. This link will highlight all of the one hundred and thirteen posts in the previous a are eight data bases on this blogspot, namely, the Glossary of Cultural and Architectural Terms, Timelines of Fabrics, Dyes and Other Stuff, A Fashion Data Base, the Glossary of Colors, Dyes, Inks, Pigments and Resins, the Glossary of Fabrics, Fibers, Finishes, Garments and Yarns, Glossary of Art, Artists, Art Motifs and Art Movements, Glossary of Paper, Photography, Printing, Prints and Publication Terms and the Glossary of Scientific Terms. All data bases in the future will be updated from time-to-time.
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 (click on "File", and then point cursor to "Mail Contents On This Page" and release). Either way, this or 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 and so undoubtedly, some parts of any Art Resource post may appear far too technical for your needs (skip those mind boggling parts) and in other parts, it may be too simplistic with respect to your level of knowledge (ditto the skip). The trade-off between these two extremes will mean that Art Resource posts will be hopefully useful in parts to most, but unfortunately may not be satisfying to all!
White Pigments - Part II [1]
Zinc White
Zinc White a term peculiar to the artists' material trade, where it is intended to describe Zinc Oxide of the highest degree of purity.
The manufacture and sale of artists' colors is an insignificant branch of the color industry, and other white pigments, such as lithophone, contain zinc, and in the past, because of the disorganized system of nomenclature, were frequently sold as Zinc White. The best grades of domestic dry Zinc Oxide are sold under the trade name of Florence French Process Zinc Oxides. There are three varieties, all of which are more than 99% pure, and any one of which may be identified as such, as the differences between them are not great.
White Seal is the finest-grained and fluffiest; Green Seal is just white, but denser and less bulky; Red Seal is slightly inferior in whiteness and fineness of grain to the others. A grade of still higher chemical purity is also available under the name of B.P. Zinc Oxide, but this is made for pharmaceutical preparations and so has inferior paint pigment's or physical properties. White Seal is generally best suited for artists' paints.
Zinc White, as a paint, is free from the two defects of Flake White. It is not poisonous, and since Zinc Sulphide is white, any action that sulphur fumes might have on Zinc Oxide in a painting, will not alter its color. Flake White in oil is adequately white, as is evidenced by its brilliant effects on many old paintings, when they are in good, clean condition, but Zinc is still whiter. If Flake White is called Milk White, then Zinc could be called Snow-White. In oil, it has a harsher, colder or bluer effect, and is very much less opaque. It is employed in oil only where its lack of great opacity is either desirable or of no detriment; if a more opaque white is required, Flake White or a mixture of 50% titanium with Zinc White is used.
Zinc White is a reactive pigment oil (see a future post in this series). It unites, but not in the same way, as Flake White does. It tends to make brittle, hard films in comparison with tough, flexible films of White Lead. Its film has none of the desirable paint qualities described under the term, 'Flake White.' It brushes out poorly, and it is an exceptionally bad drier. Its particle structure is rather finer than that of the average pigment. Poppy oil films are definitely less permanent with Zinc than with Flake White.
Under severe weathering conditions, such as those to which an outside painted house are subjected (and which may be taken, in a measure, as accelerated or exaggerated indications of the conditions an artistic painting may undergo over a long period of years), White Lead films decay by becoming soft and powdery, whereas in the case of zinc films, they become brittle, and cracking and flacking are evident; in the average climate, mixtures of the two, containing not more than 60% of either, are more resistant to decay than is Zinc or Lead alone. An addition of 10% of Blanc Fixe, increases durability of such outdoor paints, evidently by reinforcing the structural strength of the film.
Although Zinc Oxide is a very slow drier in linseed oil, and remains rather soft and flexible for some time, the oxidation of the oil is merely retarded; the drying action will continue until the film has reached its characteristic hard brittle condition. Hence, Zinc Oxide, is not as good as Flake White or Cremnitz White for use in underpaintings; it is liable to be the cause of cracking, on account of shrinkage in volume, accompanying the slow drying of the film. The danger is increased by its finely divided particle size, and it is more likely to take place when poppy oil is used. In general, Zinc White, especially when ground in poppy oil, may be considered of greatest value as a top coat, or in simple, direct, one-sitting painting.
In all aqueous medium, Zinc White is free from defects and gives very good results. It has long been used as a water color under the name of Chinese White, and when thus employed, its opacity is usually satisfactory. Where has not sufficient hiding power, as in work done for photographic reproduction, titanium should be subsituted for it.
Lithopone
Lithopone is used for interior wall paints, in enormous quantities, but despite its modern improvements made in its properties, it is universally condemned as an artists' white. In oil paints it is considerably inferior in color and color stability to Zinc Oxide. However, it has good opacity, and its structural or film-forming properties are excellent; therefore, it is generally considered acceptable for use in grounds, either in water or in oil mixtures. Its fineness of grain may cause trouble when used with poppy oil. Lithopone has a structural advantage over Zinc Oxide in oil grounds and underpaintings, namely because its films tend to dry more completely and thoroughly within a comparatively short timeframe, and moreover, to be less brittle.
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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