Chemical paint is a type of decorative finish (DF) listed in the National Button Society Blue Book glossary under "Paint" and in the Section 6, Black Glass definitions (6-4.3). During the development of the clear and colored glass educational resource (click here to access), examples of buttons with chemical paint DF were provided by two collaborators. However, questions and challenges were posed on the accuracy of the chemical paint DF designation. One of the questions related to whether or not one of the examples might be etched rather than chemical paint. In addition, the basic nature of the chemical paint was challenged in terms of (1) whether it is always smooth to the touch or whether it might have a textured surface; (2) whether it is applied and then fired/fused or not; and (3) where the term came from.  A survey of about six experienced collectors/dealers resulted in various interpretations and failed to provide clues as to how chemical paint might be different than "normal" paint.

While none of the questions related to chemical paint are likely to impact competition or garner much excitement, your editor is always fascinated when specific button class references in the Blue Book cannot be fully explained by the button gurus. Thus, I conducted a brief review to determine what might be learned from the study of several glass buttons with that dull grayish DF that seems to be characteristic of the chemical paint description. Examples of buttons with a chemical paint DF were kindly provided by Barbara Hefner (primary example below) and later by Lou Yeargain, Gloria Badger, and Barbara Barrans. The primary example would probably not be used for competition because of chips but was perfect for the limited, destructive tests intended. The images and notes below and on page 2 provide the results of the review and testing.

Summary of Results (based on the two examples shown below)
(1) The DF defined as chemical paint is likely a paint type product that was fired after its application to a finished molded glass button. It seems to be more common with but not limited to black glass.
(2) For the examples examined, the pictorial or pattern design edges were smooth and continuous indicating the use of a stencil during paint application.
(3) Several of the experts described chemical paint DF as "smooth to the touch." While this was true for most of the examples examined, none were smooth when compared to the untreated glass surface or compared to the smooth surface of most lusters.
(4) It seems likely that, at the time of application, chemical paint DF had texture (maybe significant) and might have been felt by touch. All but one example below and on page 2 have a surface texture that is smooth to the finger but can be felt/heard with a fine blade passed over the surface (like occurs with etched glass.) Visual magnification often shows small areas of fragile paint remaining above the surface.
(4) Chemical paint DF may have been an earlier, or cheaper, or manufacturer specific application of fired paints on buttons. They seem very susceptible to wear and lack the durability of other common paint/enamel finishes.
(5) The grayish image remaining after the original DF is removed by wear is mostly the result of paint fused into the surface of the glass by firing (see oil film test below) Some etching effect may be present as seen in the tortoise glass examination at the bottom of the page.
(6) It is possible that the chemical paint DF, at the time of application, came in varied brighter colors that are rarely found due to the lack of durability of the finish (see BG water foul example below).
(7) I found no persuasive reasons to make any changes to the Blue Book based on this limited review. After all, paint is paint, and without any definitive attributes, identifying any particular button as "chemical paint" is purely speculative and subject to individual interpretation. In other words, if the test results for a button do not satisfy one's notions of acceptable attributes, then it will not be a chemical paint DF to that person.

Shown at left is the front and back of the chemical paint example as received from Barbara. Note that the upper part of the figure is lighter than the bottom half. None of the photos or scans shown have been doctored other than to significantly adjust the contrast and brightness of the overall button in order to see the effects and get consistent comparisons. The button measures 11/16" x 7/16".

The upper left scan shows the as-received button. The center picture shows the button after using a razor edge blade to shave/scrape over the design in the areas of the palm tree on the right and the arm/handle/sleeve portion of the design on the left side of the standing figure. Only a very small amount of paint material was removed by the blade but left the scraped area with the same darker gray appearance as the bottom of the standing figure. The magnified picture at the right (about 35x) is of the left side of the head and handle. Note that the remnants of the paint coating above the surface on the head and upper body of the figure show up as lighter (more reflective) grayish green hues. No great force was required on the blade to create the darker gray surface. Thus, it seems obvious that the original surface coating has been worn away by use and handling over the past 100-200 years since its probable manufacture. In addition, because the removal of the surface layer did not result in a shiny black glass surface, the original paint was either fired onto the original button or some type of acid base paint was used that caused an etched surface to enhance paint adhesion. So the question becomes - is the darker gray surface at the bottom and the darker gray scraped areas the result of embedded/fused paint or is it a surface etching from the original application process? See below for the test of these alternatives.

The right hand image above is a high resolution scan of the chemical paint example with a thin film of oil applied to the surface. Note that the pictorial design on the button remains completely visible. To insure the image was not the result of easily removable paint embedded in an etched surface, I applied an aggressive paint solvent and then a lacquer thinner to a portion of the gray image with no affect. This seems persuasive that the gray image is the result of paint fused into the glass from firing and not just an etched affect. Note that the oil film removes most of the visual dings and scratches (unintended etching) but does not diminish the design. The possibilities that original colors were not grayish and that etching can be a factor are discussed in the following two examples.

Magnified Inset