Oct.,
1912
THE J O U R N A L OF I M D U S - T R I 4 L A-YD E S G I S E E R I S G CHE;1IISTRY.
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the cement can close over the shoulder of the bulb on the market to-day map be divided into two classes: and so imprison it when hardening takes place. When I n the first are cobaltous oxide, acetate, sulphate, these precautions are taken the apparatus gives no chloride, nitrate, hydroxide, and basic carbonate. I n trouble and the bulb is easily withdrawn from the the second class are various grades and qualities of hard cement a t the end of the test. The temperature resinates (sometimes called sylvinates), both fused gradients are usually taken for a twenty-four hour and precipitated, oleates or linoleates, oleo-resinates, period, although this is not necessary unless the full tungates and resino-tungates, besides some other liquid preparations composed in whole or part of the cooling curve is desired. In presenting these notes on the temperature foregoing. From the varnish manufacturer’s standpoint the gradients of setting cements, i t is not the intention of the writer to draw any conclusions at this time in substances in the first division are crude materials regard to the mechanism of the hardening reactions. which are utilized in the production of the compounds The curves obtained on the revolving scale are in the second class, and also in the preparation of transferred to centigrade degrees and plotted in some varnishes, liquid driers, drying oils, and the socalled paint oils. The materials enumerated under rectangular coordinates as is shown in curves 1 - 3 2 . An inspection of the curves will show that in some the second class are the result of a varnish maker’s cases the temperature gradients are much steeper and labor, and when properly made and used in mixtures more sudden than in others. Curves 6 , 7 , 8 and 2 1 t o which they are adapted give very good results. The inorganic salts of cobalt do not directly come represent cases in which the water was simply poured on to the dry cement without previously kneading under the scope of this paper, and thus will not be the mass to a paste. I n no case of this kind is a rise directly considered except inasmuch as their use as in temperature noted following the final set or harden- crude material affects the driers into whose composition they enter. ing, a t about seven to eight hours. I t is only within the past year that the cobalt driers In the cases of some brands of cement, as is shown in curves 9 , I O , 1 1 and 1 2 , the rise in temperature is have been offered to the American paint and varnish constant and gradual t o a maximum which usually manufactureres. Up to the present time their use occurs a t about ten to eleven hours. In other cases, is not general, first, because of the very high price, notably in curves 1 7 and 2 9 , the rise is sharp and and second because their use is not thoroughly undersudden. As both types of cement pass muster in the stood and many experimenters have had unsatisfacstandard tests, i t is not possible a t the present time tory results and therefore refused t o further consider to state what the ideal temperature gradient curve the introduction of the new material. Furthermore, not all of the cobalt driers, whether liquid, paste, or for a cement should be. That the maxima and shape of the curves is modified solid, now offered for sale, are properly made and truly by the addition of various salts t o the tempering water adapted to the purposes for which they are recomis shown in curves 1 3 , 14, 1 5 , 1 6 , 1 7 , 18, 1 9 , 2 0 and 2 2 . mended. This situation in addition to unsatisfactory Perhaps the most extraordinary curve is number results obtained by some of those experimenting, 19 which shows the heating effect produced by satu- would naturally have a retarding effect on the introrating the water with calcium sulphate. I n this case duction of a new type of material. The salts of cobalt which are a t okr disposal in the temperature rose above the scale of the recording device and the test piece became uncomfortably hot commercial quantities, are all of the cobaltous or t o the hand. Since calcic sulphate is used as a re- ,divalent type. It has been found that although they strainer when ground with a cement, this extraordinary can be readily used in the manufacture of driers and effect of calcic sulphate solution is difficult to explain. worked like the various compounds of manganese, Curves 2 5 , 2 6 , 2 7 and 2 8 were from cements which lead, zinc, calcium, aluminum, etc., the organic comdid not stand test and had been rejected. The ab- pounds formed, which are the basis and active prinnormality of these curves is at once apparent to the ciples of the so-called driers, are not efficient while eye and furnishes the best argument as to the value of in the cobaltous state. The cobaltic combinations, a study of the temperature gradient as an additional however, are very active driers, and i t is for the formation of trivalent cobalt compounds t h a t we strive method of control in cement testing. I n conclusion, the author wishes t o point out t h a t in the making of driers. This transformation can be these notes on the study of temperature gradients are effected in several ways. By blowing cold, heated, offered not as data on which to establish theories but or ozonized air through the hot cobaltous drier stock, to stimulate other workers to include similar investi- or by the introduction of liquid or solid oxidizing gations in their studies of the hardening of. hydraulic agents. The use of cold or even heated air is a very long and tedious operation if carried out to the extent cements. to which i t is necessary in order to get the maximum I N S T I T U T E O F I N D U S T R I A L RESEARCH, ~ ‘ A S H I S G T O N , D. C. strength in the drier, and greatly adds to the cost of a n already expensive material. The use of the liquid COBALT DRIERS.’ or solid oxidizers can be carried out successfully and By V. P . KRAUSS. The cobalt compounds which are generally offered in a comparatively short time, although even when great care is exercised the batch of material is in dan1 Paper presented at the Eighth International Congress of Applied ger of catching fire. Chemistry, New York. September, 1912.
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T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y .
Since driers are used in a number of industries in which drying oils form part of the material produced, and since the operating methods of the various manufacturers are widely divergent, the siccatives or driers adapted t o each will in many instances show widely different characteristics, not merely in form but also in composition. Since the paint manufacturer and also the practical painter who mixes his own paints from paste colors and raw or treated oil, are the principal consumers of what are generally known as driers, the materials adapted for their use may be first considered. The driers will, in practically all instances, be in the liquid state, either very fluid, of heavy consistency or of a semi-paste nature. In composition, they will mostly consist of resinates, tungates, oleates, or linoleates, or combinations of the three. For the drying of linseed oil, when the proper driers are selected, little or nothing can be asked in addition to those known a t present. When the general lead, manganese and other prevalent metallic driers are well chosen, raw linseed oil can without any difficulty be made to dry by the addition of from 5 to I O per cent. or even less, the time of drying under average weather conditions being from I O to 24 hours. By the use of cobalt driers, the same drying effect can be obtained when only from I to 3 per cent. of a liquid drier is used. I a m not yet prepared t o say positively what the ultimate effect of cobalt driers is upon paint films, but from my experiments I am led to believe that cobalt has not the harmful progressive oxidizing action that some of the usual manganese lead compounds have. I t has also been noticed that although a cobalt drier may be fairly dark in color, it will not have a s darkening a n effect as one of the usual driers of like color wpuld have upon a white paint. The cobalt driers likewise show the same phenomena as some of the others when used in excessive amount; that is, although the paint film will set up well in the usual time, the drying action apparently reverses and the film remains tacky. The terms applied to liquid driers are often uncertain and a p t to be misleading. There are no general standards for strength or consistency, and, i t must be admitted, many of the materials found on the market contain more volatile thinners than is conducive t o obtaining a maximum drying effect with a minimum quantity of drier. The value of the cobalt specialties depends not on their power t o dry linseed oil, but on their ability t o make the lower priced semi-drying oils act like it. Soya, fish, and even corn and cottonseed oil are adaptable for use in paint, and when correctly treated increase its durability. Dr. Maximilian Toch has published the results of his extensive research and experimental work with both fish and soya oils, and there describes the types of driers suitable for them. I n the making of waterproof fabrics, insulating coatings, etc., both liquid and solid driers are used. I n the linoleum, oilcloth, patent leather, artificial leather and similar industries, the semi-liquid, paste, and solid driers are in demand since for these products
Oct.,
1912
the manufacturers cook the oils and varnishes in their own factories. The paste and solid driers must essentially be considered under the caption of crude materials because they must be churned or cooked in the oils or varnishes in which they are used. The methods of making both solid and liquid driers are in general similar in the first stage of the process, and thus may be described under the same headings. R E S I N A T E O F COBALT, P R E C I P I T A T E D AND FUSED.
This is correctly made by saponifying rosin or colophony with caustic soda or sodium carbonate, care being taken to avoid an excess of the reagent, and then precipitating with a solution of some salt of cobalt. The chloride or sulphate serve best for this purpose. The precipitated resinate, or as it is sometimes called, rosinate or sylvinate, must then be thoroughly washed and then pressed and dried. This will yield a pinkish, fairly fluffy powder when ground, which will readily dissolve in oil a t a low temperature. The fused variety is made by melting the dried resinate in a kettle and then pouring into cooling pans. The operation is performed more rapidly by taking the cakes from the presses and driving off the water and fusing in one operation. COBALT O L E A T E S OR L I N O L E A T E S .
The basis of this class is generally linseed oil, although walnut, perilla, soya, and some other oils may be used. The oil is thoroughly saponified with caustic soda and, like the resinate, precipitated with a salt of cobalt. The material is then carefully washed and pressed. I t may be melted to form a dark viscous heavy fluid. Several samples of cobalt linoleate which I examined consisted of bodied linseed in which small amounts of inorganic cobalt salts had been dissolved. Another was of the same order with the addition of volatile solvents. True linoleate of cobalt, when fused with varnish gums and dissolved in volatile oils, yields a n excellent drier. OLEO-RESINATES.
This type of drier is made by melting together the precipitated resinate and linoleate, sometimes with the further addition of fused fossil gum-resins. T U N G A T E O F COBALT.
Like the linoleates, the tungate of cobalt is made by saponifying pure China wood oil (tung oil) with caustic soda, care being taken to avoid excess of caustic, and then precipitating with a salt of cobalt. The tungate is then washed thoroughly, pressed and generally dried and fused. Great care is necessary in the preparation of a tungate since it oxidizes very rapidly, and the oxidized material is useless. Like the linoleate of cobalt, the tungate may be fused with the resinate t o form what may be called a resino-tungate. I n general, the foregoing substances are incorporated in oils by means of heat, the combining temperature being between 300' and 500' F. The amount necessary will vary from about per cent. to 5 per
Oct., 1912
T H E JOURNAL OF I N D U S T R I A L A N D ENGINEERING CHEMISTRY.
cent. I n order t o make liquid driers, the paste or solid driers can be melted alone or in combination with gum-resins, bodied linseed oil, or both, and then thinned t o liquid consistency with volatile oils. Among other cobalt salts, some of the chemical manufacturers offer the acetate, with directions for its use as a drier. All agree t h a t between two- and four-tenths of one per cent. are necessary t o dry linseed oil. The oil should be a t a temperature between 300’ and 400’ F., and be carefully stirred until all the salt is dissolved. Soya and China wood oil may be similarly manipulated. I t is still a little too soon t o make a positive statement as t o how oils thus treated with the acetate withstand wear and exposure. Cobalt oxide, like the acetate, can be directly added t o oil during boiling. I t however dissolves slowly and necessitates heating t o high temperature ; the resulting product is also very dark, and mostly consists only of bodied oil. Rosin also will directly combine with cobalt compounds on heating together in a suitable kettle or container. The product possesses a number of objectionable features. It still is mostly unchanged rosin, has become much darker and lost considerably in weight due t o volatilization. I have tried the effect on oils of quite a number of cobalt compounds, but found none equal in efficiency t o those described in the foregoing. RESEARCH LABORATORY.
TOCHBROTHERS, NEW
PORK.
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THE DEVELOPMENT OF HYDROSULPHITES IN THEIR RELATION TO MODERN DYESTUFFS.’ B Y PHILIP
s. CLARKSON.
I n 1869 when Schuetzenberger first made sodium hydrosulphite and in 1872 when he, together with Lalande, applied it t o the preparation of indigo-white and introduced a vat for indigo dyeing based on its use, a basic foundation was laid for the practical application t o the fibre of the latest and the most desirable group of synthetic dyestuffs. These are now known technically as “vat colors” but some better term should be applied to them than one derived from the large vats or dye vessels necessary on account of the quantity of sediment in the old style method of indigo dyeing. As is well known. these products are insoluble in water and require reduction, generally in a n alkaline solution, t o render them soluble and suitable for use in the dye kettle. The old methods of fermentation, etc., used with indigo are not applicable here and the hydrosulphites are found t o be the most satisfactory agents, being most energetic in reducing action, and in the form of their sodium salts giving no insoluble combinations with the dyestuffs. Before the discovery and invention of the now large group of vat dyestuffs, the use of hydrosulphite in dyeing was small, and the improvement in manufacture of hydrosulphites not marked, but coincident with the discovery of new coloring matters suitable for use in vat dyeing came new interest in the use of hydrosulphites as discharging agents in calico printing. 1 Paper presented at the Eighth International Congress of Applied .Chemistry, New York. September, 1 9 1 2 .
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This led t o the discovery of the formation of stable compounds with formaldehyde for which the first American patent appeared in 19041 followed by t h a t for the production of pure sodium hydrosulphite powder in 1905,sthat for sodium formaldehyde sulphoxylate in the same year and finally the two zinc salts in the year 1911. These may be said t o represent the products now in commercial use, the pure , sodium hydrosulphite powder (Na,S,O,) representing the products used for dyeing, the formaldehyde compounds those used for printing and for discharging. These are a s follows: Sodium-formaldehyde-sulphoxylate, NaSO,.CH,O 2H,O, which is commercially known as hydrosulphite N F conc., Rongalite C and hyraldite C extra, accord! ing t o the maker. This is the compound of especial interest to the calico printers. Di-zinc- f o r m a l d e hyde sulphoxylate,3 ZnSO,CH,O, is known t o the trade as hydrosulphite A 2,decrolin or hyraldite 2. This is used only for stripping or removing dyestuffs f r o m d y e d materials. Mono-zinc-formaldehyde sulphoxylate,4 2 n ( H S 0 ,C H , 0 ) z , which is hydrosulphite -4 2 soluble conc. This is used for the same purpose as the di-zinc salt, but is moreeffective and is soluble in r#oE‘ virwater. The other commercial marks represent mixtures with various substances for special purposes. Practical Applications.-These comprise dyeing, printing, discharge-printing on dyed materials, and stripping or the removal of dyestuffs and coloring matters from previously dyed material. The dyestuffs which require the use of hydrosulphites are a s commonly classed: indigo and substituted indigoes, usually halogen substitution for hydrogen ; indigoids, those having the molecular construction of indigo but having other replacements; and anthracene compounds. Dyeing.-The method of application for all these classes of dyestuffs is practically the same; the dyestuff is reduced with 1 1 / ~ times t o twice the amount of sodium hydrosulphite in the presence of alkali t o dissolve the leuco compound formed. This reduced dyestuff is then applied t o the fibre in the well known manner and the color finally developed by oxidation. Various assistants are added t o secure technically
+
f
r
2
C.S. Patent KO.769,593, Des Camp. E. S . Patent No. 793,559, Bazlen and Wohlfart.
4
Ber. d . chem. Ges.. 1908, p. 4657. B. Fran., 435,260.
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