MAT ERI ALS FOR PERM AN ENT PAI NT I N G A MANUAL FOR M ANU FACT U RER ART DEA ER ART I T S. L S. S S AND COLLECT O RS By M a x imilia n Tocfi M ember American In stitute Chemical E ec u M unici Lec ture r on a Paints Co lo rs Etc . Co e e o f the p l , , g it o i w C y f h e Yo rk ' Past President of the Chemim Club Past Chairman Soc iet Che mical ndu str Se ction y I y N . Y . D of ire ctor Che mical Labo rato ry of T och Brothe r: uthor of th he mist e C r of M ixed Pain“ Etc . A y , Fello w of the Chemical Soc iety o f Lo ndo n Etc . Etc . n e w r o a x D . V A N N O S T R A N D C O M P A N Y 1 9 1 1 u p L l Cow mc a'r 1911 D. VAN NOST RAND COMPANY The Eddy Pres: Corporation Cumberland. Md. C o n t e n t s TABLE OF CONTENTS P History of ainting. P igments used by the Ancients . Sinopia , the Search for the Mas ’ ters secret . Photo-Chemical Deterioration of Oil P aintings . Cause of the Cracking of Paintings and the Remedi es . M Chapter Canvas , Wood and etal as Foun dations . V II P , reparation of Canvas in Commer ci al P i ract ce . I l i VI I , Renovation and C eaning of P c tures . The School of Impressionism . Volatile Solvents . P icture Varnishes . Driers . Linseed Oil and Other Drying Oils . Class ification of the Pigments and their Description . P The ermanent Colors . P igments Dangerous to Health . a P m ff Ch pter ig ents a ected by Coal Smoke , etc . \ Vater in Tube Colors . P m P Chapter ig ents which are ermanent . etc . P igments which Dry Slowly . ’ The failure of Sir J . Reynold s P aintings . Permanent Painting LI ST OF I LLU STRATIONS Gesso Tempera Painting on Wood F ron tispiece Photo-Micrograph of a Section of an Oil Paint ing Showing Cracks The Engineering Features of a Painting at Rest . 42 P -M in P n hoto icrograph of Cracks a ai ting, and Dirt and Dust Encysted in the Varnish Painting on Mahogany Panel Showing Serious Cracks Produced by Varnishing the Picture Be fore the Underlying Coat was S ufiicien tly Dry . 48 Photo-Micrograph of Cracks Invisible to the Naked Eye Showing Encysted Matter and Fissures . 63 Photograph of an Oil Painting Showing Serious Cracking Throughout , Due to the Contraction of the Paint 80 High -power Photo-micrograph of Flake White which Contains too much Water in its Composi tion P r e fa c e PREFACE N the course of my acquaintance with artistic painters , I was astonished to find the enormous amount of ignorance that exists among them as to the co mposition of the materials which they use i l i and the science of pa nting . A most every pa nter of note will tell you what a great pity it is that the s c cien e of making colors is lost , and that the ancient painters and great masters were so successful primar ily because their pigments and materials were far su r - h pe ior to those which we can obtain to day . T is statement is so diametrically opposed to the facts that I have been prompted to make a study of paint pigm ents in order to throw some light on this sub ce s j t , and demon trate to the painter that the colors of to-day are far superior to the colors used by t he n a cients , and show that the principal fault lies with a the manuf cturer , who makes fugitive colors , for the use of which there is no scientific nor commercial rea ’ son . Almost any large dealer in artists colors has 200 . upwards of pigments on sale In the first place , a no p lette could hold any such quantity , and in the n I D 1 suffi c i n t seco d place, there are possibly only or 5 e l i y permanent pigments to warrant the r use . Th e c orrect , complete and most edifying book on [ 5 ] P r e fa c e t eflort this subject has never been writ en , nor is my e of much value , xcepting perhaps from the stand of i point the chem st . Some day there will be born will i r a man , who be both a color chemist and a pa nte , and that man will write the ideal book on the subject . The popular impression is that all chemists mus t have a comprehensive knowledge of the chemistry o f pig n m me ts , but this is not true , as there are very few che ists who know anything about the technology o f a au fe w p ints , bec se it is a specialty which very have r e wo ked up , and no matter how proficient a ch mist n ot a n may be , if he is an artistic p i ter , he cannot u advise how a sky should be painted , or what partic lar greens to use for foliage and shadows . The technique of the fine arts is a subject by itself , and while I may be supposed to have so me knowledge on this sub ect d i in j , I frankly a mit my nability to paint , but asmuch as I feel very certain of one part of my sub ce of j t , that is the physical and chemical properties a c the pigments, I do not hesit te to re ommend in plain language exactly what the painter shall do with refe r his i he ence to colors , and the materials upon wh ch paints . fi n d Furthermore , I was very much astonished to that in the art schools of the various countries no at tention whatever is paid to the chemistry of colors . A painter should be aware that certain pigments are afi ectcd by the fumes arising from vegetables in a n di ing room , and that these fumes form chemical com [ 6 ] P r e f a c e o d l p un s with certain pigments , and a painter shou d likewi se kn ow that the atmosphere of large ci ties is con taminated with acid gases which are absent in c s smaller pla e , and which did not exist before the age of the burning of coal as fuel . I trust, therefore , that my work will be taken serious l he y, and that the poorer painter will recognize that need not use expensive colors to produce permanent u res lts. I am glad that I am not actuated by any com mercial motive in writing this book , for , although I a have been a color manufacturer for m ny years , I have e t k n ve r made , nor have I the inten ion of ma ing tube l ’ co ors for artists use , but I have made quantities of e m n of fin ly ground colors for a y my friends , who are in pa ters , and have demonstrated to them that some i i t mes the ord nary paints ground in oil , such as are ffi used by house decorators , are su ciently good for in many purposes , and many instances produce the same results as the more expensive colors filled in v tubes . I ha e tried to write as fully as I know and give as plainly as I could the description relating to o the m re expensive colors , condemning those which i should be condemned , and recommend ng others as long as there is nothi ng superior to be had . It may inte res t the reader to know why I take such i i a pos t ve stand with reference to the fading, drying and other physical characteristics of colors , in view of the fact that the majority of investigators vacillate i l con t n ua ly . I 7 ] P r e f a c e 1 886 was In , while I still a chemical student , I made my first investigation of tube colors , and from that day to t his I have been interested in the subject of the manufacture of paints and pigments as a vo t cation , and have always been in erested in the sub j cet of the application of artistic pigments as an avo i . r in cat on D ying tests can , of course , be conducted al a few weeks, but extensive tests take years , and though it is reaso nable to determine the permanen cy of a color by exposure to the bright sunshine for r th ee months , I have made experiments along these w r lines hich have involved exposu e for over five years . When pigments are mixed with an aqueous medium t lt u containing a lit le gum , and the resu ing pict re is a s be hermetic lly sealed , no decomposition take place , cause the majority of chemical reactions cease in the oil absence of moisture , but linseed or varnish medium will generate moisture and certain gases , producing a a slow decomposition , so that it often takes ye rs to make a determination of which a description can be t e writ en in a few minut s.