A filter material for reducing the content of harmful substances in tobacco smoke. The filter material comprises a ground and not additionally activated expanded clay produced without adding foreign substances, and zeolite as the filter material. The filter is suitable for tobacco products such as cigarettes, cigars and cigarillos, and for smoking articles such as tobacco pipes and cigarette and cigar holders.

1. Field of the Invention
The invention relates to a filter material for reducing harmful substances in tobacco smoke.
2. The Prior Art
Tobacco smoke is produced when tobacco is burning down. Said smoke is an aerosol consisting of a gas phase and a condensate phase. The gas phase of the tobacco smoke has a relatively simple composition and, in addition to nitrogen, oxygen, carbon dioxide, hydrogen and inert gases, also contains the toxic substances carbon monoxide (about 4.2%), hydrogen cyanide (about 0.16%), ammonia (about 0.03%), nitrogen oxides (about 0.02%), and traces of hydrogen sulfide. On the other hand, the main component of ingredients is found in the condensate phase (xe2x80x9ctarxe2x80x9d), including also the flavoring and odorous substances forming the aroma of tobacco smoke.
It is known since a long time that smoking is harmful to health in the long run. It has not as yet been entirely clarified which components of tobacco smoke in detail exactly cause the effects, which are observed to varying degrees depending on the smoking habits, the tobacco consumption and the constitutional disposition of the smoker, etc. The statistically increased susceptibility of smokers to arteriosclerosis, coronary diseases and myocardial infarction, as well as the tendency to gastrointestinal diseases are ascribed to the effects of nicotine, and attributed to some extent also to the effects of carbon monoxide. Another toxic substance, namely hydrocyanic acid, inhibits the regeneration of the ciliary epithelium in the respiratory tract, and prevents the formation of leukocytes. The very frequent occurrence of diseases in the region of the pharyngeal space, and in particular the occurrence of bronchitis (smoker""s cough) are associated with the phenol, acid, aldehyde and ketone components of tobacco smoke.
Filter cigarettes, filter cigars and filter cigarillos, as well as cigarette and cigar holders and tobacco pipes have been developed for reducing the content of harmful substances in tobacco smoke, with mouthpieces containing filter materials for removing part of the nicotine and tar substances without substantially filtering out the aroma substances. Such filter materials consist of cellulose, cellulose acetates, polyethylene, crepe and paper, or active carbon.
Silicate-containing minerals, in particular clay, kaolin and feldspat are used as adsorbents for tobacco filters according to DE-OS 15 17 272. However, the drawback is that said filter materials, according to the laid-open specification of said patent, have to be made free of adhering ions by means of a treatment with distilled water or acids, or by electrolysis or electrodialysis, in order for them to be usable. Furthermore, mainly tar substances of the condensate phase and less the toxic substances of the gas phase are reduced.
Furthermore, filter materials are used which form a film, and which consist of a binding agent such as methyl cellulose and a finely fibrous material, the latter being provided with adsorbents. Active carbon, silica gel, asbestos fibers or polyethylene glycol are specified as adsorbents. Said filter material offers the advantage of filtering out defined harmful substances, in the present case primarily phenol, by applying selectively acting absorbents. In addition to the use of asbestos fibers, which have been proven to cause cancer, the drawback in this case is that the major part of the flavoring and odorous substances of the tobacco aroma is filtered out.
DE-OS 15 17 298 specifies filter materials consisting of active carbon grains with a maximum diameter of 0.1 to 2 mm, which are linked via a vehicle such as polyvinyl resin or polyethylene. Again, the drawback is that mainly the tar substances and thus also the flavoring and odorous substances of the tobacco smoke aroma are filtered out, but not the toxic components of the gas phase such as carbon monoxide, hydrocyanic acid or ammonia.
According to DE design patent 87 06 686, another filter material consists of a mixture of active carbon particles and meerschaum (sepiolite), which serves for reducing the tar substances, harmful substances and the nicotine, as well as the odorous substances. Meerschaum or sepiolite represents a porous mineral, which adsorbs much moisture in addition to tar substances and nicotine. The adsorptive effect of the active carbon for odorous, harmful and tar substances is increased by binding the moisture. However, the drawback is that in addition to the odorous substance, the flavoring substances of the tobacco smoke aroma are filtered out as well.
In German laid-open document DE-OS 29 25 001, mention is made of clays as filter materials, which can be applied to carrier materials such as cellulose acetate fibers or paper because of their gel- and film-forming properties. Decisive for the application of such materials is their swelling property. Therefore, primarily bentonites such as sodium montmorillonite and sodium attapulgite are suitable.
Furthermore, filters are known for cigarettes, cigars, cigarillos, cigarette and cigar holders as well as tobacco pipes which contain either pure silica gel or pure active carbon.
The drawback of such filter materials is that they predominantly reduce the tar substances of the condensate phase, but less so the toxic substances of the gas phase. Since the flavoring and odorous substances forming the aroma of tobacco smoke are present also in the condensate phase, and reduced jointly with the tar substances, the utilization of such filter materials has a negative influence on the pleasure of smoking. A further drawback of such materials is the short duration of the filtration effect of said filter materials. Particularly with filter materials used in cigarette and cigar holders as well as in tobacco pipes, which are reused many times, the degree of saturation and thus the loss of filtration efficiency are reached in a relatively short time. Furthermore, the smoker is required to apply increased drawing force when smoking with some filter materials because the density of the filter material is so great that the tobacco smoke will not freely flow through the filter material.
The invention is based on the problem of providing a filter material which, in addition to improving the reduction of the tar substances present in the condensate phase, eliminates the toxic substances of the gas phase as completely as possible without reducing at the same time the aroma of the tobacco smoke and thus the flavoring and odorous substances. Furthermore, the goal of the invention is to provide a filter material that assures long-lasting filtration efficiency and permits easy passage of the tobacco smoke through such filter material without requiring the smoker to apply increased drawing force during smoking.
This object is accomplished by a filter material that comprises a ground and not additionally activated expanded clay produced without adding foreign substances, as well as zeolite. The expanded clay is a synthetically produced filter material based on natural lime-containing raw clay. To produce the expanded clay, the natural raw or crude clay is shaped into small, round pieces and subsequently burned in special calcinators, so-called rotary tubular furnaces, at a high temperature (about 1200xc2x0 C.) with a feed of air.
The small round pieces are first caused to expand in the course of the burning process under heat, and the surfaces of the small spheres of clay are then slightly sintered (melted). The interior of the small spheres has a porous structure with numerous air inclusions. The expanded clay is thereafter ground.
Therefore, the expanded clay is produced without adding any foreign substances. An expanded clay so produced has an optimal filtration effect and does not need to be additionally activated. Thus, there is no additional process required to turn the ground expanded clay into a more reactive activated condition.
By using expanded clay as filter material for tobacco products such as cigarettes, cigars or cigarillos, and for smoking utensils such as tobacco pipes, cigarette and cigar tips, the harmful substances of the condensate phase and in particular of the gas phase are very highly reduced without negatively influencing at the same time the flavor and the odor of the aroma of the tobacco smoke.
The advantage of using expanded clay instead of untreated clay lies in the fact that expanded clay, because of its production process (burning process at 1200xc2x0 C.), has air cavities and air ducts extending through it, so that the surface for adsorbing the harmful substances present in the tobacco smoke is enlarged. The fine ducts favor in this connection the precipitation of condensate and of the harmful substances contained therein.
Furthermore, expanded clay is characterized by its low swelling property and the dimensional stability associated therewith, which prolongs the duration of the filtration effect. The large surface area of expanded clay, because of the large contact area between the filter material and the tobacco smoke, assures a long-lasting filtration effect. The drawing force the smoker is required to apply for smoking changes unnoticeably when expanded clay is employed; the smoke flows without obstruction through the filter material with good surface contact.
By using zeolite as filter material, harmful substances of the condensate phase and gas phase are minimized as well. In the present case too, a material is employed which, on account of its surface structure, is characterized by cavities and ducts, and significantly suitable for filtering out the harmful substances of the tobacco smoke while having only minor influence on the aroma of the tobacco smoke.
The advantage of zeolite over other silicate-containing minerals such as silica gel and clays consists in its surface structure, which has excellent hydration, ion exchange and molecular screen properties. As compared to conventional, commercially available silicone-containing filter materials, this improves the reduction of harmful substances in the gas and condensate phase of tobacco smoke.
Furthermore, in spite of their surface areas, the two materials expanded clay and zeolite take up only little volume, so that a small amount of material suffices for good filtration effects.
According to a further development of the invention, provision is made that the filter material is a composition of expanded clay and zeolite. The composition may vary within wide limits.
In this way, the filtration effect is improved as compared to the one of the individual substances in spite of using only the same amount of filter material. The improvement of the filtration effect has to be attributed to the fact that the individual substances mutually positively influence each other with respect to their activity, i.e., with respect to their efficiency in adsorbing harmful substances.
Furthermore, it is possible to add components in the form of active carbon particles to the expanded clay, the zeolite, or to the mixture of expanded clay and zeolite.
The filtration properties are intensified beyond the additive measure of the individual components in this way as well. The composition may vary within wide limits. The proportion of active carbon particles is dimensioned in this connection in such a way that the influence on flavoring and odorous substances remains as low as possible.
The filter material may be in the form of granulate with a grain size with a diameter in the range of 0.1 and 2 mm.
The upper limit of the grain size is to assure that adequate packing density and a sufficient degree of filling are obtained, and that mixing or at least partial penetration of the filter materials may occur as well. The lower limit is to avoid excessive flow resistance and to prevent very small particles from being carried along by the flow and from exiting from the filter.
Zeolite having a finely fibrous structure is preferably employed; this prevents fine fibers from getting detached and from being carried along by the flow and inhaled.
According to a further development of the invention, provision is made that the substances forming the filter material are usable unmixed next to each other in the form of a multiphase system.
This increases the filtration efficiency and filtration capacity. In a two-phase system, for example, harmful substances of the tobacco smoke are filtered out in the first phase; such harmful substances otherwise negatively influence the filtration effect of the second phase. Accordingly, in a multiphase system, the phases can be arranged in such a way that the best possible mutual positive influencing of the filter materials is achieved for reducing the harmful substances of the tobacco smoke.
Furthermore, the substances forming the filter material can be used also intermixed in the form of a mixed-phase system.
In this way, the filtration effect and filtration capacity are increased selectively for individual harmful substances.
Such an increase is caused by the close contact between the filter materials and the mutual positive influencing of their filtration effects and capacities resulting therefrom.
Furthermore, provision is made that the filter materials are usable without activation.
In this way, no costly pretreatments (washing with acids, lyes or H2O; heating; swelling; homogenizing; drying; etc.) of the filter materials are required, which, as a rule, means cost savings. (Swelling refers to a process that changes the volume of a solid when it is acted upon by liquid.)
The filter preferably comprises a consumption indicator.
In this way, the end of the adsorption capacity for adsorbing harmfull substances is optically indicated on the filter materials. Starting from a defined indication, the filter should be replaced because the adsorptive power of the filter material is getting too low for effectively minimizing the harmful substances contained in the tobacco smoke.
In a practical realization, the consumption indicator may consist of marble.
The end of the adsorption capacity for adsorbing harmful substances on the filter materials is indicated in this way by a discoloration of the marble from light to dark, and the filter should be replaced starting with a defined depth of the color.
Cellulose has the same property as marble in this regard. With cellulose, too, a certain dark coloration indicates the end of the capacity for adsorbing harmful substances. As opposed to marble, however, cellulose additionally has a filtering property. When cellulose is used mixed with the materials specified above, the filter has an above-average filtration effect. The proportion of cellulose in the mixture is limited in that when higher proportions are used, the drawing force which the smoker has to apply during smoking is highly raised, while the flavor and odor of the tobacco diminish ar the same time.
The consumption indicator is preferably arranged downstream of the filter material in the direction of flow. Such an arrangement offers the advantage that a visual change sets in only when the filter materials are almost consumed. When this situation exists, the change in the consumption indicator accors rapidly, signaling the end of the usability of the filter in a clear manner.

Filter material for reducing harmful substances in tobacco smoke


A conjugated linoleic acid is prepared in industrial scale as a hydrolyzed isomerized product for blending into bulk domestic animal feeds. The CLA-containing isomerized hydrolyzed oil from sunflower and safflower seeds has sufficiently low levels of phosphatides and sterols to permit crude processing and incorporation into feeds of an undried, undistilled oil fraction without toxic or unpalatable effects.

This invention relates to a new use of conjugated linoleic acid in animal feeds. The conjugated linoleic acid is manufactured in an industrial scale process from seed oils such as sunflower oil and safflower oil, which contain non-fatty acid residues low enough to avoid final purification by distillation, but still pure enough to be safely fed to animal in bulk feed.
Processes for the conjugation of the double bonds of polyunsaturated unconjugated fatty acids have found their main application in the field paints and varnishes. Oils comprised of triglycerides of conjugated fatty acids are known as drying oils. Drying oils have value because of their ability to polymerize or xe2x80x9cdryxe2x80x9d after they have been applied to a surface to form tough, adherent and abrasion resistant films. Tung oil is an example of a naturally occurring oil containing significant levels of conjugated fatty acids.
Because tung oil is expensive for many industrial applications, research was directed towards finding a substitute. In the 1930""s, it was found that conjugated fatty acids were present in oil products subjected to prolonged saponification, as originally described by Moore, J. Biochem., 31: 142 (1937). This finding led to the development of several alkali isomerization processes for the production of conjugated fatty acids from various sources of polyunsaturated fatty acids.
In alkali isomerization the fatty acids are exposed to heat, pressure and a metal hydroxide or oxide in nonaqueous or aqueous environments, resulting in the formation of conjugated isomers. Other methods have been described which utilize metal catalysts, which is not as efficient in the production of conjugated double bonds. It was found that isomerization could be achieved more rapidly in presence of higher molecular weight solvent. Kass, et al., J. Am. Chem. Soc., 61: 4829 (1939) and U.S. Pat. No. 2,487,890 (1950) showed that replacement of ethanol with ethylene glycol resulted in both an increase in conjugation in less time. U.S. Pat. No. 2,350,583 and British Patent No 558,881 (1944) achieved conjugation by reacting fatty acid soaps of an oil with an excess of aqueous alkali at 200-230 degrees C. and increased pressure.
Among the processes known to effect isomerization without utilizing an aqueous alkali system, is a nickel-carbon catalytic method, as described by Radlove, et al., Ind. Eng. Chem.38: 997 (1946). A variation of this method utilizes platinum or palladium-carbon as catalysts.
Purified conjugated linoleic acid (xe2x80x9cCLAxe2x80x9d) has recently been shown in several studies to have unique properties when used as a food additive. Purified CLA appears to affect fat deposition in animals. Purified CLA both increases the lean to fat ratio, effectively reducing body fat, and increases feed conversion efficiency. An additional advantage of feeding CLA is that it appears to modulate immune responses under certain conditions. In laboratory animal studies CLA has been shown to prevent weight loss due to immune stimulation and to treat immune hypersensitivity.
The purified CLA utilized in prior studies as an animal feed additive was obtained by small scale laboratory procedures involving production of CLA from highly purified linoleic acid. Laboratory and pilot scale oil refining systems have been described for preparation of purified seed oils. For example Sullivan, J. Am. Oil Chemists"" Soc., 53: 359 (1976), describes a laboratory semi-pilot steam refining system made entirely of glass.
While these systems are adequate for producing quantities of conjugated fatty acids for laboratory studies, or even clinical trials, they are not suitable for commercial scale bulk production. On the other hand, the large scale systems available to produce industrial quantities of conjugated acids, as in classical drying oils, cannot be run inexpensively enough to produce material for bulk animal feeds. The standard degumming, refining, and dehydration steps necessary to obtain nutritionally safe edible conjugated oils for livestock feeding, are prohibitively complex and expensive. (See Braae, J. Am. Oil Chemists"" Soc., 53: 353 (1976) for a discussion of complex degumming processes as practiced on a commercial scale in Europe). Also there are significant losses of product through polymerization of conjugated fatty acids or their precursors at high temperatures.
Economical CLA production in commercial quantities for use in domestic food animal feeds is a desirable objective in light of the nutritional benefits realized on a laboratory scale. Preferably, the CLA is produced directly from a source of raw vegetable oil and not from expensive purified linoleic acid. Further, the process must avoid cost generating superfluous steps, and yet result in a safe and wholesome product palatable to animals.
In the present invention, a feed safe conjugated linoleic acid is manufactured according to a method otherwise used for producing an industrial grade conjugated product for use in paint and varnish. Typically, residues (i.e. the chemically modified end products resulting from heat and pressure) derived from non-oil components of seed oils, such as sterols and phosphatides, form unpalatable, or even toxic by-products under processing conditions. Generally seed oils such as corn or soy bean oil must be extensively degummed, and the sterols and phosphatides are meticulously removed in a series of purification steps to avoid fouling of equipment, and to recover a wholesome product. In addition to removal of impurities and by-product polymerized or carmelized material during processing, it is necessary to acidify and finally distill the oil to obtain product of requisite purity for use in food. Subjecting the oil to isomerization causes further impurities, and requires even more rigorous decontaminating and by-product removal.
Surprisingly, the Applicant has discovered that a complex purification scheme for producing a feed safe conjugated linoleic-containing oil is not necessary, if the starting material is an oil having less than 0.5 percent phosphatides, and an unsaponifiable sterol fraction containing less than 20 percent each of campesterol and stigmasterol. According to this criteria, sunflower and safflower oil are suitable starting oils for production of the present feed safe CLA enriched oil, but soybean oil or corn oil are not suitable because of the high unsaponifiable content, and also high levels of linolenic acid that tends to readily polymerize. It is further desirable to have a starting oil with a high linoleic acid content, so that the final product has a correspondingly high CLA content.
The present invention encompasses the new use in domestic animal feed of conjugated linoleic acid produced from a seed oil, especially sunflower and safflower oils, but not soybean or corn oils, having a linoleic acid content of at least 50 percent produced by an industrial scale process in which the crude oil is subjected to the steps of solvent extracting, as with hexane, alcohols, or polyols known in the art, fat splitting, treating with aqueous alkali to effect at least 50 percent isomerization of the double bonds of linoleic acid to form conjugated linoleic acid at low temperatures below about 230 degrees F., and preferably below about 215 degrees F., acidifying with a mineral acid, and separating the oil fraction from the majority of the aqueous fraction without a distillation step.
In the conjugation of linoleic by isomerization of the double bonds, the fat splitting step releases the free fatty acids from the glycerol backbone molecule. After the alkali treatment step followed by acidification, several water wash steps may be required to remove salts, and then the water content of the oil fraction can be reduced (after simple decanting the upper fat layer) by conventional centrifugation methods to a content of less than 10 percent. The presence of some water will not interfere with animal feed formulating. In fact, the presence of some water aids the mixing and homogenization step, and provides a source of steam during extrusion.
The animal feeds of the present invention are compounded from the conventional ingredients in rations typical for the species and age of the domestic animal to be fed, in addition to from 0.2 to 5.0 percent of a sunflower or safflower oil having a total C18:2 content of 50-80 percent in which at least 50 percent of the linoleic acid has been isomerized to the conjugated linoleic acid form. Such feeds retain their palatability and wholesomeness even though the CLA containing oil is obtained by an industrial process normally reserved for production of drying oils for paint and varnish. One principal advantage in this new use, is that animal feeds containing nutritionally effective amounts of CLA to achieve reduced body fat content, and firmer fat content in pork, become economically feasible when the CLA can be manufactured in quantities of at least 5 tons per batch or continuous uninterrupted run, without expensive purification and distillation steps.
The present invention relates to the large scale, commercial production of an edible conjugated fatty acid product from crude extracted sunflower or safflower oil. Processes for conjugating polyunsaturated fatty acids have been developed by the paint and varnish industry. Conjugated fatty acids were required for the production of drying oils. These drying oils need not be of edible grade, and therefore no purification is required to remove impurities which do not affect their drying function. Recently, purified conjugated linoleic acid (xe2x80x9cCLAxe2x80x9d) has been shown to be effective in increasing feed efficiency and increasing the lean to fat ratio of animals. CLA has been shown to be effective in increasing the lean to fat ratio in animals as disclosed in U.S. Pat. No. 5,554,646, increasing the feed efficiency of animals as disclosed in U.S. Pat. No. 5,428,072, and tempering adverse effects of the immune response as disclosed in U.S. Pat. Nos. 5,430,066 and 5,585,400. The foregoing patents are herein incorporated by reference. In order to realize the commercial potential of CLA for these purposes, it is necessary to produce large quantities of a CLA product at a low cost so that it can be adapted to domestic animal feed rations.
Various methods of producing conjugated double bonds by alkali isomerization are known in the art. U.S. Pat. No. 2,350,583 (Bradley, 1944) describes a method of producing conjugated fatty acids by aqueous alkali isomerization. This method resulted in the conjugation of about 50% of the double bonds present in the polyunsaturated fatty acids used. U.S. Pat. No. 2,242,230 (Burr et al., 1941) describes a method of non-aqueous alkali conjugation of fatty acids, resulting in the conjugation-of approximately 100 percent of the double bonds in the polyunsaturated fatty acids studied. Another process resulting in the efficient formation of conjugated double bonds is described in U.S. Pat. No. 4,381,264 (Struve, 1983). There, the inventors treat polyunsaturated fatty acids with SO2 in the presence of substoichiometric amounts of soap forming bases. Perhaps the most commercially viable method for producing large quantities of conjugated fatty acids is the continuous flow aqueous alkali isomerization process described in U.S. Pat. No. 4,164,505. This process results in especially all available double bonds being conjugated in a short reaction time. The foregoing patents are incorporated herein by reference.
The present invention describes the use as a feed ingredient of a CLA produced by a combination of the continuous countercurrent fat-splitting process and the continuous flow alkali isomerization process.
CLA, so produced, is a mixture of the conjugated isomers of polyunsaturated fatty acids found in sunflower or safflower oil. Therefore, the conjugated fatty acids will contain conjugated isomers predominantly of linoleic acid and to a lesser extent linolenic acid. CLA is a mixture of one or all of the isomers of octadecadienoic acid including the cis-9, trans-11; cis-9, cis-11; trans-9, cis-11; trans-9, trans-11; cis-10, cis-12; cis-10, trans-12; trans-10, cis-12; and trans-10, trans-12 isomers. The cis-9,trans-11 and trans-10, cis-12 isomers are thought to possess most of the biological activity. Preparations of CLA which contain primarily these isomers are thus preferred. In general, it is preferred that the fatty acid preparation contain at least 50% CLA and have a ratio of cis-trans isomers of CLA to trans-trans isomers of CLA of about 5.1 to 8.1.
Crude sunflower or safflower oil is the preferred fatty acid source for producing CLA. Sunflower oil contains a high amount of linoleic acid (about 65% on average). Safflower oil typically contains even higher amounts (greater than 70%). Preferably, a hexane extract of crude, non-degummed oil is the starting substrate for CFAP production. This extract is commercially available and is the same quality as the oil used as the starting point for edible products. The ability to use raw sunflower or safflower oil as the starting substrate provides an important economic advantage because it is less expensive than refined sunflower oil.
Applicants have discovered that other raw oils; such as raw corn and soybean oils, are not suited to the present new use of CLA in bulk feeds because of the production of polymerized products during the fat splitting and conjugation processes, and because of the high phosphatide content. Also, certain sterols such as campesterol and stigmasterol are known to have a tendency to foul processing equipment during conjugation and plug nozzles during materials transfer. The polymerization by-products also result in loss of yield from these other oils, even though at first glance the other oils may seem to have more desirable properties. Corn oil (about 56% linoleic acid) and soybean oil (about 50-55% linoleic acid) have comparable linoleic acid contents as compared to sunflower oil (about 60% linoleic acid). These oils are inexpensive and large quantities are available, which make them attractive candidates as a potential source of CLA for bulk feeds. However, their use for commercial CLA production is substantially lower per unit quantity of oil because the ultimate yields of CLA are lower than for sunflower or safflower oil, and because of the added expense for additional cleaning and purification steps.
Heat sensitive triglycerides containing multiple double bonds are abundant in oils having an iodine value above 120. Oils containing such heat-sensitive triglycerides have a tendency to form polymers when subjected to continuous countercurrent fat-splitting. These polymers become insoluble in oil and will foul equipment, resulting in lowered efficiencies of splitting and yields. Sunflower oils are classified as heat-sensitive because of their high linoleic acid content and iodine number. Sunflower oil has an iodine number of 130; safflower oil of about 145. Soybean oil has an iodine number of about 132, and corn oil has an iodine number of about 130. All these oils have high linoleic acid contents and iodine numbers above 120, thus belonging to the heat-sensitive group. It is therefore surprising that sunflower and especially safflower oils can be split and conjugated by commercial processes with few processing complications.
The second cause of lower yields relates to the level of impurities present in unrefined oil. Crude oils contain relatively high amounts of various impurities such as phospholipid, proteinaceous and mucilaginous matter, carbohydrates, pigments, waxes and insoluble. It is normally necessary to degum and then alkali or mechanically refine these oils to remove the impurities. Degumming involves treating the crude oil with water to hydrate and precipitate phosphatides and gummy mucilaginous substances. The prevalent phosphatides are phosphatidylethanolamine, phosphatidyliniositol and phosphatidylcholine. The phosphatide content of sunflower and s lower oils is about 0.4 to 1.0% as reported in Klein and Crauer, JAOCS 51:382A-385A and Burkhardt, JAOCS 48:697-699 (1971), respectively. In contrast, the phosphatide content of soybean oil is about 1.5-2.5% as reported in the Handbook of Soy Oil Processing and Utilization, Erickson et al. eds., AOCS, Champaign, 1980. For crude oils with low amounts of these substances, such as sunflower and safflower oils, proceeding can advance directly to caustic refining, after degumming.
As described above, oils are generally degummed by precipitation after hydration with water. It can be expected that gums in the crude sunflower oil utilized in the present invention would be hydrated during both the fat-splitting and aqueous isomerization processes. Such precipitates may be the cause the fouling of the equipment. Sunflower oil and safflower oil generally contain similar amounts of phosphatides and could be expected to behave similarly in processing.
The presence of phosphatides in the crude oil also raises other concerns. It is well known in the art that phosphatides in oils may be charred when subjected to cream refining or deodorization and bleaching. These phosphatides may be present in the oil even after repeated treatment with caustic soda. The residual phosphatides cause poor taste and low oxidative stability as discussed in Braae, JAOCS 53:353-357 (1976). The counter-current fat-splitting and continuous flow aqueous isomerization processes utilized in most modern processes share several common aspects with steamrefining and deodorization including operation at high temperatures and the presence of steam. Therefore, it could be expected that phosphatide residues present with the free fatty acids produced by fat-splitting and carried over to and not removed by the isomerization process would cause poor taste and oxidative instability in the CLA containing oil. For a comparison of sunflower/safflower oil and corn/soybean oil, refer to Table 1.
The first step in the production of bulk animal feed containing CLA is hydrolysis of the raw sunflower oil to form free acids and glycerol. The preferred fat-splitting process is version of the Colgate-Emery process described in Sonvtag, Fatty Acids in Industry, Fat Splitting and Glycerol Recovery, Johnson and Fritz, eds., Marcel Dekker, Inc., New York, pp 23-72 (1989), incorporated herein by reference. This process involves the countercurrent reaction of water and fat under high temperatures and pressures.
The equipment used for this process is standard in the industry. The equipment consists of a highly elongated, cylindrical-shaped tower about 20 to 48 inches in diameter and 60 to 80 feet high. The tower is made of stainless steel or some other corrosion resistant material and can withstand operating pressures of about 750 psig.
In operation, the raw sunflower or safflower oil is pumped into the tower by means of a sparge ring about 3 feet from the bottom of the tower. Water is introduced near the top of the column at about 40 to 50% of the weight of the fat. The sunflower oil rises through the hot glycerol-water collecting section at the bottom of the column and passes through the oil-water interface into the continuous phase where the hydrolysis takes place in the oil layer. Direct injection of high pressure steam is used to maintain the temperature at 250xc2x0 C. Pressure is maintained at about 700 to 750 psig.
Pressure in the column is maintained by means of a back-pressure control valve in the fatty acid discharge line. The level of the interface is maintained by controlling the discharge of the water phase. Close control of the heat exchange at each end of the column is essential for efficient separation because of the solubility of water in fatty acids and of the fatty acids in glycerine water at the extremely high operating temperatures.
The second major step in the process is conjugation. Preferably, the continuous flow aqueous alkali isomerization process is used. This process is described in U.S. Pat. No. 4,164,505, incorporated herein by reference.
The alkaline reagent used in the process is any water soluble alkali metal hydroxide, for example NaOH or KON. The alkali must be provided well above stoichiometric excess, preferably greater than about a 50-100% excess.
The fatty acids derived from the continuous countercurrent fat-splitting process are charged with the metal hydroxide into a flow reaction zone maintained in many conventional processes at a pressure of about 25-300 psi and a temperature of about 230xc2x0 C. In the recommended method of isomerization, low temperatures in the 210-220xc2x0 C. range should be maintained to avoid predominance of trans isomers. Retention times may be increased commensurating to retain yields. Sufficient water must be admitted to the flow reaction zone so that the alkali metal salts which are formed remain in solution. The total time in the reaction zone is preferably about 30 minutes, or longer at decreased temperatures. Typical flow rates are about 10 liters/minute. The flow reaction zone can generally take the from simple tubular flow reactor provided with an inlet for feeding in the sunflower fatty acids, and outlet for removing CFAP, and a means to monitor the composition of the reaction product.
Next, the preparation is acidulated in a batch reactor. Preferably, diluted sulfuric acid is added to the mixture to neutralize the strong alkali. The bottom layer containing sodium sulphate is removed. Then, the remaining fatty acid layer is washed with water and dried under a vacuum at about 80xc2x0 C. to 100xc2x0 C. For the production of edible conjugated fatty acid product, a distillation step is not needed.
Example 1 shows the composition of a typical CLA-containing isomerized sunflower oil produced by the above processes. The ratio of cis-trans to trans-trans isomers was greater than 7:1.
This oil produced by the combination of the continuous countercurrent fat-splitting and continuous flow alkali isomerization processes may be added to animal feed formulations as a source of CLA.
Many different feed rations may be formulated for animals from many different feed ingredients. Rations are generally formulated to provide-nutrients in accordance with National Research Council standards. The feedstuffs used in the ration are chosen according to market price and availability. Thus, some components of the ration may change over time. In the feeds of the present invention, the ration will always contain CLA-containing isomerized sunflower or safflower oil in a concentration of 0.05-5.0 percent, but other components may vary over time based on the price of the component. For discussions on feed ration formulation, actual rations and NRC guidelines, see Church, Livestock Feeds and Feeding, OandB Books, Inc., Corvallis OR (1984) and Feeds and Nutrition Digest, Ensminger, Oldfield and Heineman eds., Ensminger Publishing Corporation, Clovis, Calif. (1990), incorporated herein by reference.
The animal feed rations of the present invention may be characterized according to NRC requirements. NRC requirements may be found in Church, Livestock Feeds and Feeding, OandB Books, Inc., Corvallis Oreg. (1984), or other nutritional standards. Hog and other animal rations are traditionally balanced using the protein and energy requirements, and then adjusted if needed to meet the other requirements. The hog and other feeds of the present invention will contain about 0.05% to 5% lipids plus other feed materials necessary to balance the feed to meet the NRC requirements for the different stages of growth and maintenance. Preferably, the ration will contain about 0.1 to 1.0% CLA-containing isomerized hydrolyzed oil and most preferably about 0.25-0.5%. The amount of oil incorporated into the ration is not critical as long as it is enough to be effective in decreasing body fat and increasing feed efficiency or eliciting other desirable responses.
Tho relative amounts of protein and energy are adjusted to reflect Nutritional Standards requirements. The amounts of feed components will vary with the stage of animal fed. A growing ration for young animals will have higher protein levels, while a finishing ration for finishing animals for market will have higher energy values which are supplied by carbohydrates. For example, hog prestarter, starter and grower-finisher rations will generally contain about 20-24% protein, 18-20% protein and 13-17% protein respectively. In some feeding situations, care must be taken to provide the appropriate amino acids as well as overall protein content. For example, hogs fed large amounts of corn must have adequate lysine made available in the ration. In most animal diets, energy requirements are met by starches in cereal grains. Energy requirements may also be met by addition of fat to the ration. In the present invention, the CFAP provides part of the energy requirement. Addition of fat to hog rations has been proven to increase growth rate slightly. Feed intake is reduced and feed efficiency is improved when fat is added to the ration. Since feed intake is reduced when fat is added, it important to increase the level of protein so that the daily intake of protein is maintained. In general, the protein level should be increased by 0.2% for every 1% addition of dietary fat.
The CLA-containing isomerized hydrolyzed oil in the rations of the present invention meets the definition of hydrolyzed fat contained in the 1997 Official Publication, Association of Feed Control Officials Incorporated (1997). Feed grade hydrolyzed soap making. It consists predominantly of fatty acids, and must contain not less than 85% fatty acids, not more than 6% unsaponifiable matter, and not more than 1% insoluble impurities. The oil used in the present invention is hydrolyzed sunflower oil (fat) produced by the combination of the commercial countercurrent fat-splitting and continuous flow alkali isomerization processes, or commercial variation thereof in common use. During these processes, the raw sunflower or safflower oil is hydrolyzed and conjugated to form a hydrolyzed fatty acid product.
Other ingredients may be added to the feed ration. These ingredients include, but are not limited to, mineral supplements such as calcium, phosphorus, salt, selenium and zinc; vitamin supplements such as Vitamins A, B, D, E, and K; amino acid supplements such as lysine; coccidiostats, except in hog feeds, or growth promoters such as bacitracin or virginamycin; and other active drugs such as chlortetracycline, sulfathiozole, and penicillin. For vitamin, mineral and antibiotic supplement formulation see Church, Livestock Feeds and Feeding, OandB Books, Inc., Corvallis Oreg. (1984).
In a preferred embodiment, the oil is incorporated into a pelleted feed for administration to domestic animals. Pelleted feed is created by first mixing feed components and then compacting and extruding the feed components through a die with heat and pressure. The feed is pelleted by methods known in the art, which are described in MacBain, Pelleting Animal Feed, American Feed Manufacturers Association, Arlington, Va. (1974), incorporated herein by reference. When incorporating added fat into pelleted feed, caution is needed in order to avoid making mealy pellets. Generally, only about 2% of the fat is added during pelleting, with the rest added after the pellets have cooled. Alternatively, the CLA-containing isomerized hydrolyzed oil could be added directly to a simple crushed or blended feed ration. Alternatively, the CLA-containing isomerized hydrolyzed oil could be added directly to a simple crushed or blended feed ration.
The oil and the feed containing the oil may be stabilized by the addition of antioxidants. Therefore, antioxidants may be added as chemical preservatives in aaccordance with F.D.A. regulations as listed in the 1997 Official Publication, Association of Feed Control Officials Incorporated (1997), herein incorporated by reference. Suitable antioxidants include, but are not limited to: Lecithin, tocopherols, ascorbate, ascorbyl palmitate and spice extracts such as rosemary extract.
Rations containing edible CFAP may also be formulated for animals other than hogs. The amount of CFAP administered is not critical as long as it is enough to be effective in decreasing body fat and increasing feed efficiency or other benefits. The feeds are formulated as above, and tailored to the requirements of the animal to be fed in accordance with NRC guidelines. For example, feeds may be formulated for dogs, cats, poultry and cattle. Various rations are given in the examples. Various feed formulations, balancing methods and requirements for these animals are discussed in Church, Livestock Feeds and Feeding, OandB Books, Inc., Corvallis Oreg. (1984) and Feeds and Nutrition Digest, Ensminger, Oldfield and Heineman eds., Ensminger Publishing Corporation, Clovis, Calif. (1990), incorporated herein by reference. It should be borne in mind that feed companies and livestock producers develop their own nutritional requirements based on historical results. The present invention makes the use of CFAP possible in these various feeds because the CFAP may be produced economically in bulk quantities.
The oil containing feed must be palatable to domestic animals, especially hogs consuming the feed. Hogs are known to have acute olfactory senses and to refuse feed with undesirable odors. Therefore, it is surprising that a process used to produce drying oils in varnishes and paints can be adapted to produce a feed additive that is both safe to feed and palatable to hogs.
The CLA may also be utilized in oil form produced by reesterification to glycerol, or a powder or gel of the free fatty acid. Additionally, the CLA may be derivitized to form a non-toxic salt, such as a potassium or sodium salt, which is formed by reacting chemically equivalent amounts of the free acids with an alkali hydroxide at a pH of about 8 to 9.
The following Examples further illustrate the invention.

Bulk animal feeds containing conjugated linoleic acid


The present invention provides novel crystalline (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate useful for reducing or preventing bone loss as well as pharmaceutical compositions containing the same. A process for preparing (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate is described.

This invention relates to crystalline (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate herein referred to as levormeloxifene maleate, its preparation and use as therapeutic agent.
U.S. Pat. No. 5,280,040 and U.S. Pat. No. 5,464,862 discloses a class of 3,4-diarylchromans and their salts useful for reducing bone loss. U.S. Pat. No. 5,453,442 describes methods of lowering serum cholesterol and inhibiting smooth muscle cell proliferation in humans and inhibiting uterine fibroid disease and endometriosis in women by administering compounds of formula I as shown therein.
The preparation of 3,4-trans diarylchromanes is described in U.S. Pat. No. 3,822,287 and by Suprabhat Ray et al. in J. Med. Chem. 19, 276 (1976), the contents of which are incorporated herein by reference. The resolvation of (+/xe2x88x92)-3,4-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane in its optical antipodes is described in U.S. Pat. No. 4,447,622 incorporated herein by reference. Example 1 describes the preparation of the minus enantiomer, shown by formula I:
(In this specification the compound of formula I is referred to as levormeloxifene.)
In example 2 of U.S. Pat. No. 4,447,622 levormeloxifene is obtained as the free base and the hydrochloride salt.
However, the free base has a very poor solubility in water and the hydrochloride salt has some pharmaceutically undesirable properties. The hydrochloride salt is hygroscopic, it is quite heavy soluble in water and it forms a solid gel in aqueous suspension.
For commercial use it is important to have a physiologically acceptable salt with good stability, non-hygroscopicity, good bioavailability, good handling properties, and a reproducible crystalline form.
Within one aspect, the present invention provides crystalline (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate.
Within another aspect of the invention there is provided a pharmaceutical composition comprising crystalline (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate optionally in combination with a pharmaceutically acceptable carrier or diluent.
Within another aspect of the invention there is provided a process for the preparation of crystalline (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate, which process comprises dissolving maleic acid and (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane in a common solvent, and crystallizing the resulting salt from the solution.
Within another aspect of the present invention there is provided a method of using the compound according to the invention to prevent or reduce bone loss.
It has now been discovered that crystalline (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate has the above described desired properties. In contrast to the hydrochloride salt, which is very hygroscopic, the hydrogen maleate salt is non-hygroscopic. Furthermore the hydrogen maleate salt has good stability characteristics, good bioavailability, good handling properties, and a reproducible crystalline form
Accordingly, the present invention provides crystalline levormeloxifene maleate as a novel material, in particular in pharmaceutically acceptable form.
The present invention also provides a process for the preparation of crystalline (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate, which process comprises dissolving maleic acid and (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane in a common solvent, and crystallizing the resulting salt from the solution.
Examples of the common solvents include but are not limited to organic solvents in particular lower aliphatic alcohol""s such as ethanol, 2-propanol, 2-butanol, 1-hexanol and solvents like toluene, isobutylmethylketone and tetrahydrofuran. The mixture of the components are conveniently performed at temperatures from 40 to 60xc2x0 C. before cooling down to 5xc2x0 C. and collection of the crystals by filtration.
The present invention also provides a pharmaceutical composition comprising crystalline (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate optionally together with a pharmaceutically acceptable carrier or diluent.
Crystalline (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate may be used in human and veterinary medicine for the regulation of bone metabolism. The present invention provides thus according to another aspect a method of preventing or reducing bone loss in a mammal in need of such treatment or prevention comprising administering a therapeutically effective amount of the compound according to the invention. Levormeloxifene maleate may be used, for example, in the treatment of patients suffering from bone loss due to osteoporosis (including post-menopausal osteoporosis and glucocorticoid-related osteoporosis), Paget""s disease, hyperparathyroidism, hypercalcemia of malignancy and other conditions characterized by excessive rates of bone resorption and/or decreased rates of bone formation or in patients susceptible to bone loss. Furthermore, the compound has effects on the cardiovascular system where it lowers serum cholesterol, inhibits lipid accumulation in the arterial wall, acts as a vasodilator and interferes with the coagulation process, wherefore it may be used for the prevention and treatment of, for example, atherosclerosis, hyperlipidemia and hypercoagulability. It may also be used, for example, in the treatment of female patients suffering from endometriosis, dysfunctional bleeding, endometrial cancer, polycystic ovarian syndrome, anovulatory bleeding and breast cancer and male patients with gynecomastia, prostate hypertrophy and prostate carcinoma. It may also be used to induce endometrial thinning prior to intrauterine surgery. Furthermore, it may be used, for example, to treat menopausal symptoms, and atrophy of mucous membranes and skin. The compound may be used, for example, in the treatment of patients suffering from obesity and Alzheimer""s disease.
For use within the present invention, crystalline (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate may be formulated with a pharmaceutically acceptable carrier or excipient to provide a medicament for parenteral, oral, nasal, rectal, subdermal or intradermal or transdermal administration according to conventional methods. Formulations may further include one or more diluents, fillers, emulsifiers, preservatives, buffers, excipients, etc. and may be provided in such forms as liquids, powders, emulsions, suppositories, liposomes, transdermal patches, controlled release, dermal implants, tablets, etc. One skilled in this art may formulate the compound in an appropriate manner, and in accordance with accepted practices, such as those disclosed in Remington""s Pharmaceutical Sciences, Gennaro, ed., Mack Publishing Co., Easton, Pa., 1990.
The compositions of this invention are usually adapted for oral administration, or as formulations for dissolution for parenteral administration. Oral administration is preferred.
For oral administration crystalline (xe2x88x92)-3R,4R-trans-7-methoxy-2,2-dimethyl-3-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}chromane, hydrogen maleate is prepared in a form suitable for oral administration, such as a tablet or capsule. Typically, the compound is combined with a carrier and molded into a tablet. Suitable carriers in this regard include starch, sugars, dicalcium phosphate, calcium stearate, magnesium stearate and the like. Such compositions may further include one or more auxiliary substances, such as wetting agents, emulsifiers, preservatives, stabilizers, colouring additives, etc.
Pharmaceutical compositions are administered one or more times per day or week. An effective amount of such a pharmaceutical composition is the amount that provides a clinically significant effect. Such amounts will depend, in part, on the particular condition to be treated, age, weight, and general health of the patient, and other factors evident to those skilled in the art.
The pharmaceutical compositions may be administered in unit dosage form one or more times per day or week. In the alternative, they may be provided as controlled release formulations suitable for dermal implantation. Implants are formulated to provide release of active compound over the desired period of time, which can be up to several years. Controlled-release formulations are disclosed by, for example, Sanders et al., J Pharm Sci 73 (1964), 1294-1297, 1984; U.S. Pat. Nos. 4,489,056; and 4,210,644, which are incorporated herein by reference.
The composition is usually presented as a unit dose composition containing 0.1-1000 mg of a compound in accordance with the invention for oral dosing. Typical dosage for e.g. osteoporotic effect would vary between 0.1-500 mg, preferably between 0.1-280 mg per day either once or divided in 2 or 3 doses when administered orally or 2 or 3 times per week or once weekly or once per 14 days.
Preferred unit dosage forms include in solid form, tablets or capsules, in liquid form, solutions, suspensions, emulsions, elixirs or capsules filled with the same, or in form of sterile injectable solutions, or patches, vagitories, vaginal rings or long lasting implantates.
The composition of this invention may be formulated by conventional methods of galenic pharmacy.
Conventional excipients are such pharmaceutically acceptable organic or inorganic carrier substances suitable for parenteral or oral application which do not deleteriously react with the active compound.
Examples of such carriers are water, salt solutions, alcohol""s, polyethylene glycol""s, polyhydroxyethoxylated castor oil, syrup, peanut oil, olive oil, gelatin, lactose, terra alba, sucrose, agar, pectin, acacia, amylose, magnesium stearate, talc, silicic acid, stearic acid, fatty acid monoglycerides and diglycerides, pentaerythritol fatty acid esters, hydroxymethylcellulose and polyvinylpyrrolidone and calcium phosphates.
The pharmaceutical preparations can be sterilized and mixed, if desired, with auxiliary agents, such as binders, lubricants, preservatives, disintegrants, stabilizers, wetting agents, emulsifiers, salt for influencing osmotic pressure, buffers and/or colouring substances and the like, which do not deleteriously react with the active compound.
For parenteral application, particularly suitable are injectable solutions or suspensions, preferably aqueous solutions with the active compound dissolved in polyhydroxylated castor oil.
For oral administration, particularly suitable are tablets, dragees, or capsules having talc and/or a carbohydrate carrier or binder or the like, the carrier preferably being lactose or calcium phosphate and/or corn starch and/or potato starch. A syrup, elixir or like can be used when a sweetened vehicle can be employed.
A typical tablet, which may be prepared by conventional tabletting techniques, contains:
The present invention is further illustrated by the following examples which, however, are not to be construed as limiting the scope of protection. The features disclosed in the fore-going description and in the following examples may, both separately and in any combination thereof, be material for realising the invention in diverse forms thereof.
Levormeloxifene maleate was synthesized, purified and crystallized as described in the following example.


A surfactant composition containing: (a) from about 75 to 97% by weight of an alkyl sulfate; and (b) from about 3 to 25% by weight of an alkenyl sulfate, all weights being based on the weight of the composition, and wherein the surfactant composition is in granular form.

This invention relates generally to solid laundry detergents, dishwashing detergents and cleaning compositions and, more particularly, to new surfactant granules distinguished by improved solubility in cold water, to a process for their production and to their use.
Nowadays, surfactants are preferably used in granular, substantially water-free form for the production of solid laundry detergents, dishwashing detergents and cleaning compositions. Various processes have been found to be suitable for the production of granular surfactants. However, one feature common to all commercially available surfactant granules is that they have an unsatisfactory dissolving rate, particularly in cold water. For this reason, detergent tablets based on anionic or nonionic surfactants cannot be directly introduced into the dispensing compartment of washing machines despite the use of considerable quantities of disintegrating agents; instead, they have to be directly added to the wash liquor. Anionic surfactants are important ingredients of detergents/cleaners. Where they are to form part of powder-form cleaners of high bulk density or compacted detergents, for example detergent tablets, alkyl sulfatesxe2x80x94also known as fatty alcohol sulfates (FAS)xe2x80x94are preferably used in powder or granular form. These FAS powders or granules are normally produced by spray drying or drying in a continuous fluidized bed. C16/18 fatty alcohol sulfate granules in particular, which have been produced by drying and granulation in a continuous fluidized bed, show inadequate solubility and dispersibility at low temperatures. There is a risk of traces of detergent being left behind, particularly in the case of colored washing which has to be washed at low temperatures.
Since the solution to this problem is very important for cold washing and for the use of detergent compactates, the problem addressed by the present invention was to provide long-chain alkyl sulfate granules with improved dissolving and dispersing behavior at low temperatures and to improve the dissolving behavior of detergent compactates through the use of these granules.
The present invention relates to surfactant granules consisting of
(a) 75 to 97% by weight of an alkyl sulfate,
(b) 3 to 25% by weight of an alkenyl sulfate,
with the proviso that the quantities add up to 100% by weight with water and optionally electrolyte salts, and to a process for the production of these surfactant granules.
The present invention also relates to the use of the surfactant granules according to the invention in laundry detergents, dishwashing detergents and cleaning compositions.
It has surprisingly been found that the preparations according to the invention dissolve spontaneously in water, even at low temperatures. Detergent compactates containing the granules according to the invention have a considerably shorter disintegration time and dissolving rate. Even the addition of small quantities of alkenyl sulfate leads to a distinctly better dissolving rate at low temperatures (temperatures of 25xc2x0 C.xc2x110xc2x0 C.).
Alkyl sulfate granules produced in a continuous fluidized bed also show this improved dissolving behavior. The improved dissolving behavior also leads to improved disintegration of disintegrator-containing detergent tablets (cellulose-based disintegrator systems).
Alkyl Sulfates
Alkyl sulfates, which are often referred to as fatty alcohol sulfates and which form surfactant component (a), are the sulfation products of primary saturated alcohols which correspond to formula (I):
R1Oxe2x80x94SO3Xxe2x80x83xe2x80x83(I)
where R1 is a linear or branched, aliphatic alkyl group containing 6 to 22 and preferably 12 to 18 carbon atoms and X is an alkali metal and/or alkaline earth metal, ammonium, alkyl ammonium, alkanolammonium or glucammonium. Typical examples of alkyl sulfates which may be used for the purposes of the invention are the sulfation products of caproic alcohol, caprylic alcohol, capric alcohol, 2-ethyl hexyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, palmitoleyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, elaidyl alcohol, petroselinyl alcohol, arachyl alcohol, gadoleyl alcohol, behenyl alcohol and erucyl alcohol and the technical mixtures thereof obtained, for example, by the high-pressure hydrogenation of technical methyl ester fractions or aldehydes from Roelen""s oxo synthesis. The sulfation products may advantageously be used in the form of their alkali metal salts, more particularly their sodium salts. Alkyl sulfate powders or needles based on C16/18 tallow fatty alcohols or vegetable fatty alcohols of comparable C-chain distribution in the form of their sodium salts are particularly preferred.
Alkenyl Sulfates
Alkenyl sulfates, which are often referred to as ocenol sulfates, are understood to be the sulfation products of primary mono- and polyunsaturated alcohols which correspond to formula (Il):
R2Oxe2x80x94SO3Xxe2x80x83xe2x80x83(II)
in which R2 is a linear or branched, mono- or polyunsaturated aliphatic alkenyl group containing 12 to 22 and preferably 16 to 18 carbon atoms and X is an alkali metal and/or alkaline earth metal, ammonium, alkyl ammonium, alkanolammonium or glucammonium. Alkenyl sulfates with an iodine value in the range from 5 to 60 and preferably in the range from 10 to 20 (palmocenol) or 50-55 (HD-ocenol), preferably based on C16/18 alcohols, are particularly preferred.
Residual Moisture and Electrolyte Salts
The surfactant granules according to the invention have residual moisture contents of 0.5 to 7% by weight and preferably 0.5 to 1.5% by weight, depending on the production process, the drying conditions and the storage conditions
The surfactant granules also contain free sodium hydroxide (0.2 to 1.2% by weight, preferably 0.4 to 0.8% by weight), free fatty alcohols (0.5 to 6% by weight, preferably 0.5 to 4% by weight) and varying amounts of electrolyte salts, for example sodium sulfate (0.2 to 10% by weight, preferably 0.5 to 5% by weight) and/or sodium chloride (0 to 2% by weight, preferably 0 to 0.5% by weight), from their production process.
Production Processes
The surfactant granules are produced by known processes, including SKET granulation, spray drying and droplet formation (xe2x80x9cdropletizationxe2x80x9d). The granules may also be produced by compacting which includes press agglomeration, extrusion, roll compacting, pelleting and tabletting as operations.
Fluidized Bed Granulation
A particularly preferred process for the production of the surfactant granules according to the invention comprises subjecting the mixtures to fluidized bed granulation (xe2x80x9cSKETxe2x80x9d granulation). SKET fluidized bed granulation is understood to be a simultaneous granulation and drying process preferably carried out in batches or continuously. The mixtures of surfactants and disintegrating agents may be used both in dried form and in the form of a water-containing preparation. Preferred fluidized-bed arrangements have base plates measuring 0.4 to 5 m. The SKET granulation is preferably carried out at fluidizing air flow rates of 1 to 8 m/s. The granules are preferably discharged from the fluidized bed via a sizing stage. Sizing may be carried out, for example, by means of a sieve or by an air stream flowing in countercurrent (sizing air) which is controlled in such a way that only particles beyond a certain size are removed from the fluidized bed while smaller particles are retained in the fluidized bed. The inflowing air is normally made up of the heated or unheated sizing air and the heated bottom air. The temperature of the bottom air is between 80 and 400xc2x0 C. and preferably between 90 and 350xc2x0 C. A starting material, preferably surfactant granules from an earlier test batch, is advantageously introduced at the beginning of the granulation process.
Drying and Granulation in a Flash Dryer
The simultaneous drying and granulation process may also be carried out in a horizontally arranged thin-layer evaporator or dryer with rotating internals of the type marketed, for example, by the VRV company under the name of xe2x80x9cFlashdryerxe2x80x9d or by the VOMM company under the name of xe2x80x9cTurbodryerxe2x80x9d. In simple terms, the flash dryer/turbodryer is a tube which can be heated to different temperatures over several zones. The paste-form starting material, which is introduced by a pump, is projected onto the heated wall by one or more shafts fitted with paddles or plowshares as rotating internals and is dried on the heated wall in a thin layer typically with a thickness of 1 to 10 mm. According to the invention, it has been found to be of advantage to apply a temperature gradient of 130xc2x0 C. (product entrance) to 20xe2x96xa1C. (product exit) to the thin layer evaporator. To this end, the first two zones of the evaporator for example may be heated to 120-130xc2x0 C. and the last zone cooled to 20xc2x0 C. The thin-layer evaporator/dryer is operated at atmospheric pressure, air, but preferably an alkaline gas stream, for example ammonia (throughput 50 to 150 m3/h), being passed through in countercurrent (throughput about 50-150 m3/h). The gas entry temperature is generally in the range from 20 to 30xc2x0 C. while the exit temperature is in the range from 90 to 110xc2x0 C. The throughput of the surfactant pastes is of course dependent on the size of the dryer and amounts, for example, to between 5 and 25 kg/h. It is advisable to heat the pastes to 40-60xc2x0 C. during their introduction into the dryer and to add 0.05 to 0.5% by weight, based on the solids content, of alkali metal carbonate, preferably sodium carbonate, to them in order to avoid hydrolysis processes.
In another preferred embodiment of the process according to the invention, water-containing surfactant is mixed with already dried end product on the hot contact surface. To this end, a product stream of about 10 to 40% by weight and preferably 15 to 25% by weight, based on the volumetric flow rate of the paste used, is removed at the dryer exit and directly fed back into the apparatus in the immediate vicinity of the paste entry point by means of a solids metering screw. Through this measure, the tackiness of the water-containing surfactant can be reduced and better wall contact of the product over the entire available surface can be established. In this way, transport of the product is stabilized and drying of the product intensified. At the same time, the particle size distribution of the granules can be displaced as required towards coarser products, i.e. the unwanted fine dust content can be significantly reduced, by the addition of the end product. An increase in throughput, based on analogous process conditions with no recycling of solids, can be achieved by this measure.
In addition, after drying, it has proved to be of considerable advantage to transfer the granules, which are still at about 50 to 70xc2x0 C., to a conveyor belt, preferably a vibrating chute or the like, and to cool them quickly, i.e. in 20 to 60 seconds, with ambient air to temperatures of about 30 to 40xc2x0 C. In order further to improve their resistance to the unwanted absorption of water, the granules of particularly hygroscopic surfactants may also be subsequently dusted with 0.5 to 2% by weight of silica.
Other Processes
In another embodiment, the surfactant granules are produced by extrusion as described, for example in European patent EP 0 486 592 B1 or International patent applications WO 93/02176 and WO 94/09111 or WO 98/12299. In this extrusion process, a solid premix is extruded under pressure to form a strand and, after emerging from the multiple-bore extrusion die, the strands are cut into granules of predetermined size by means of a cutting unit. The solid, homogeneous premix contains a plasticizer and/or lubricant of which the effect is to soften the premix under the pressure applied or under the effect of specific energy, so that it can be extruded. Preferred plasticizers and/or lubricants are surfactants and/or polymers. Particulars of the actual extrusion process can be found in the above-cited patents and patent applications to which reference is hereby expressly made. In one preferred embodiment of the invention, the premix is delivered, preferably continuously, to a planetary roll extruder or to a twin-screw extruder with co-rotating or contra-rotating screws, of which the barrel and the extrusion/granulation head can be heated to the predetermined extrusion temperature. Under the shear effect of the extruder screws, the premix is compacted under a pressure of preferably at least 25 bar orxe2x80x94with extremely high throughputsxe2x80x94even lower, depending on the apparatus used, plasticized, extruded in the form of fine strands through the multiple-bore extrusion die in the extruder head and, finally, size-reduced by means of a rotating cutting blade, preferably into substantially spherical or cylindrical granules. The bore diameter of the multiple-bore extrusion die and the length to which the strands are cut are adapted to the selected granule size. In this embodiment, granules are produced in a substantially uniformly predeterminable particle size, the absolute particle sizes being adaptable to the particular application envisaged. In general, particle diameters of up to at most 0.8 cm are preferred. Important embodiments provide for the production of uniform granules in the millimeter range, for example in the range from 0.5 to 5 mm and more particularly in the range from about 0.8 to 3 mm. In one important embodiment, the length-to-diameter ratio of the primary granules is in the range from about 1:1 to about 3:1. In another preferred embodiment, the still plastic primary granules are subjected to another shaping process step in which edges present on the crude extrudate are rounded off so that, ultimately, spherical or substantially spherical extrudate granules can be obtained. If desired, small quantities of drying powder, for example zeolite powder, such as zeolite NaA powder, can be used in this step. This shaping step may be carried out in commercially available spheronizing machines. It is important in this regard to ensure that only small quantities of fines are formed in this stage. According to the present invention, dryingxe2x80x94which is described as a preferred embodiment in the prior art documents cited abovexe2x80x94may be carried out in a subsequent step but is not absolutely essential. It may even be preferred not to carry out drying after the compacting step. Alternatively, extrusion/compression steps may also be carried out in low-pressure extruders, in a Kahl press (manufacturer: Amandus Kahl) or in a so-called Bextruder (manufacturer: Bepex). In one particularly preferred embodiment of the invention, the temperature prevailing in the transition section of the screw, the pre-distributor and the extrusion die is controlled in such a way that the melting temperature of the binder or rather the upper limit to the melting range of the binder is at least reached and preferably exceeded. The temperature exposure time in the compression section of the extruder is preferably less than 2 minutes and, more particularly, between 30 seconds and 1 minute.
Another method for producing the surfactant granules, granulation and compacting, may be carried out in known manner. Where this method is used, it is possible in particular to compact the granules before, during or after granulation. From the applicational perspective, it has proved to be very favorable for the surfactant granules produced to have a particle size in the range from 0.01 to 6 mm and preferably in the range from 0.1 to 5 mm and, more particularly, for the percentage of granules outside the 0.1 to 5 mm range to make up less than 25% by weight.
The surfactant granules may be produced by roll compacting. In this variant, the premix is introduced between two rollersxe2x80x94either smooth or provided with depressions of defined shapexe2x80x94and rolled under pressure between the two rollers to form a sheet-like compactate. The rollers exert a high linear pressure on the premix and may be additionally heated or cooled as required. Where smooth rollers are used, smooth untextured compactate sheets are obtained. By contrast, where textured rollers are used, correspondingly textured compactates, in which for example certain shapes can be imposed in advance on the subsequent detergent particles, can be produced. The sheet-like compactate is then broken up into smaller pieces by a chopping and size-reducing process and can thus be processed to granules which can be further refined and, more particularly, converted into a substantially spherical shape by further surface treatment processes known per se. In roll compacting, too, the temperature of the pressing tools, i.e. the rollers, is preferably at most 150xc2x0 C., more preferably at most 100xc2x0 C. and most preferably at most 75xc2x0 C. Particularly preferred production processes based on roll compacting are carried out at temperatures 10xc2x0 C. and, in particular, at most 5xc2x0 C. above the melting temperature of the binder or the upper temperature limit of the melting range of the binder. The temperature exposure time in the compression section of the rollersxe2x80x94either smooth or provided with depressions of defined shapexe2x80x94is preferably at most 2 minutes and, more particularly, between 30 seconds and 1 minute.
The surfactant granules may also be produced by pelleting. In this process, the premix is applied to a perforated surface and is forced through the perforations and at the same time plasticized by a pressure roller. In conventional pellet presses, the premix is compacted under pressure, plasticized, forced through a perforated surface in the form of fine strands by means of a rotating roller and, finally, is size-reduced to granules by a cutting unit. The pressure roller and the perforated die may assume many different forms. For example, flat perforated plates are used, as are concave or convex ring dies through which the material is pressed by one or more pressure rollers. In perforated-plate presses, the pressure rollers may also be conical in shape. In ring die presses, the dies and pressure rollers may rotate in the same direction or in opposite directions. A press suitable for carrying out the process according to the invention is described, for example, in DE 38 16 842 A1. The ring die press disclosed in this document consists of a rotating ring die permeated by pressure bores and at least one pressure roller operatively connected to the inner surface thereof which presses the material delivered to the die space through the pressure bores into a discharge unit. The ring die and pressure roller are designed to be driven in the same direction which reduces the shear load applied to the premix and hence the increase in temperature which it undergoes. However, the pelleting process may of course also be carried out with heatable or coolable rollers to enable the premix to be adjusted to a required temperature. In pelleting, too, the temperature of the pressing tools, i.e. the pressure rollers, is preferably at most 150xc2x0 C., more preferably at most 100xc2x0 C. and most preferably at most 75xc2x0 C. Particularly preferred production processes based on pelleting are carried out at temperatures 10xc2x0 C. and, in particular, at most 50xc2x0 C. above the melting temperature of the binder or the upper temperature limit of the melting range of the binder.
One feature common to all the processes is that the premix is compacted and plasticized under pressure and that the individual particles are pressed against one another and adhere to one another with a commensurate reduction in porosity. In all the processes, the tools may be heated to relatively high temperatures or may be cooled to dissipate the heat generated by shear forces.
xe2x80x9cDropletizationxe2x80x9d is a process for the production of surfactant granules in which a stream of a water-containing surfactant preparation is converted into droplets (xe2x80x9cdropletizedxe2x80x9d) by passage through a vibrating casting plate and the droplets are exposed to a gaseous drying agent flowing in countercurrent which evaporates the water present and at the same time dries the granules.
The production of granules by dropletization using a vibrating casting plate is already known for the processing of synthetic waxes, resins and low-viscosity polyesters. Corresponding units are marketed, for example, by Rieter-Automatik under the name of xe2x80x9cDroppo Linexe2x80x9d for use in the textile industry. Casting plates in the form of perforated disks are preferably used, the droplets passing through the bores into the spray drying tower. These perforated disks preferably have an output of 100 to 800 kg/h and more particularly of the order of 500 kg/h, the diameter of the bores being between 0.5 mm (mean granule diameter 0.8 mm) and 1.4 mm (mean granule diameter 2.5 mm). The vibration frequency imposed on the water-containing surfactant preparations is typically in the range from 100 to 1,000 Hz and preferably in the range from 500 to 800 Hz. Compared with conventional processes, only a light excess pressure (typically 10 to 100 mbar) is applied. Drying in the spray drying tower may be carried out with hot air or hot combustion gases flowing in countercurrent at temperatures of, for example, 100 to 150xc2x0 C., as adequately described in the prior art. The granules are substantially spherical and have mean diameters of 1 to 2.5 mm, depending on the bore diameter of the perforated plate and the vibration frequency. The dust content, i.e. particles smaller than 0.5 mm in size, is substantially zero.
Commercial Applications
The surfactant granules according to the invention contain
(a) 75 to 97% by weight, preferably 85 to 95% by weight of an alkyl sulfate and
(b) 3 to 25% by weight and preferably 5 to 15% by weight of an alkenyl sulfate,
with the proviso that the quantities shown add up to 100% by weight with water and optionally electrolyte salts.
The present invention also relates to the use of the surfactant granules for the production of solid laundry detergents, dishwashing detergents and cleaning compositions in which they may be present in quantities of 1 to 90% by weight, preferably 5 to 50% by weight and more particularly 10 to 25% by weight, based on the detergent/cleaner. The detergents/cleaners may be present in the form of powders, granules, extrudates, agglomerates and, in particular, tablets and may contain other typical ingredients.
They are preferably used for the production of detergent compactates because it is precisely in their case that dissolving rate is such a critical factor.
Auxiliaries and Additives
Besides the ingredients mentioned above, the detergent compactates may contain other typical ingredients such as, for example, builders, bleaching agents, bleach activators, detergency boosters, enzymes, enzyme stabilizers, redeposition inhibitors, optical brighteners, soil repellents, foam inhibitors, inorganic salts, dyes and perfumes.
A suitable solid builder is, in particular, finely crystalline zeolite containing synthetic and bound water, such as detergent-quality zeolite NaA. However, zeolite NaX and mixtures of NaA and NaX are also suitable. The zeolite may be used in the form of a spray-dried powder or even as an undried stabilized suspension still moist from its production. Where the zeolite is used in the form of a suspension, the suspension may contain small additions of nonionic surfactants as stabilizers, for example 1 to 3% by weightxe2x80x94based on zeolitexe2x80x94of ethoxylated C12-18 fatty alcohols containing 2 to 5 ethylene oxide groups or ethoxylated isotridecanols. Suitable zeolites have a mean particle size of less than 10 xcexcm (volume distribution, as measured by the Coulter Counter Method) and contain preferably 18 to 22% by weight and more preferably 20 to 22% by weight of bound water. Suitable substitutes or partial substitutes for zeolites are crystalline layer-form sodium silicates with the general formula NaMSixO2x+1.yH2O, where M is sodium or hydrogen, x is a number of 1.9 to 4 and y is a number of 0 to 20, preferred values for x being 2, 3 or 4. Crystalline layer silicates such as these are described, for example, in European patent application EP 0 164 514 A. Preferred crystalline layer silicates are those in which M in the general formula stands for sodium and x assumes the value 2 or 3. Both xcex2- and xcex3-sodium disilicates Na2Si2O5.yH2O are particularly preferred, xcex2-sodium disilicate being obtainable for example by the process described in International patent application WO 91/08171. The powder form detergents according to the invention preferably contain 10 to 60% by weight of zeolite and/or crystalline layer silicates as solid builders, mixtures of zeolite and crystalline layer silicates in any ratio being particularly advantageous. In one particularly preferred embodiment, the detergents contain 20 to 50% by weight of zeolite and/or crystalline layer silicates. Particularly preferred detergents contain up to 40% by weight of zeolite and, more particularly, up to 35% by weight of zeolite, based on water-free active substance. Other suitable ingredients of the detergents are water-soluble amorphous silicates which are preferably used in combination with zeolite and/or crystalline layer silicates. Particularly preferred detergents are those which contain above all sodium silicate with a molar ratio of Na2O to SiO2 (modulus) of 1:1 to 1:4.5 and preferably 1:2 to 1:3.5. The amorphous sodium silicate content of the detergents is preferably up to 15% by weight and more preferably from 2 to 8% by weight. Phosphates, such as tripolyphosphates, pyrophosphates and orthophosphates, may also be present in the detergents in small quantities. The phosphate content of the detergents is preferably up to 15% by weight and, more particularly, from 0 to 10% by weight. In addition, the detergents may contain layer silicates of natural and synthetic origin. Corresponding layer silicates are known, for example, from patent applications DE 23 34 899 B, EP 0 026 529 A and DE 35 26 405 A. Their suitability for use is not confined to a particular composition or structural formula. However, smectites are preferred, bentonites being particularly preferred. Suitable layer silicates which belong to the group of water-swellable smectites are, for example, those corresponding to the following general formulae:
where x=0 to 4, y=0 to 2 and z=0 to 6. In addition, small quantities of iron may be incorporated in the crystal lattice of the layer silicates corresponding to the above formulae. By virtue of their ion-exchanging properties, the layer silicates may also contain hydrogen, alkali metal and alkaline earth metal ions, more particularly Na+ and Ca2+. The quantity of water of hydration is generally in the range from 8 to 20% by weight and is dependent upon the degree of swelling and upon the processing method. Suitable layer silicates are known, for example, from U.S. Pat. Nos. 3,966,629, 4,062,647, EP 0 026 529 A and EP 0 028 432 A. Layer silicates which have been substantially freed from calcium ions and strongly coloring iron ions by an alkali treatment are preferably used. Useful organic builders are, for example, the polycarboxylic acids preferably used in the form of their sodium salts, such as citric acid, adipic acidic acid, succinic acid, glutaric acid, tartaric acid, sugar acids, aminocarboxylic acids, nitrilotriacetic acid (NTA), providing their use is not ecologically unsafe, and mixtures thereof. Preferred salts are the salts of polycarboxylic acids, such as citric acid, adipic acid, succinic acid, glutaric acid, tartaric acid, sugar acids and mixtures thereof. Suitable polymeric polycarboxylates are, for example, the sodium salts of polyacrylic acid or polymethacrylic acid, for example those with a relative molecular weight of 800 to 150,000 (based on acid). Suitable copolymeric polycarboxylates are, in particular, those of acrylic acid with methacrylic acid and acrylic acid or methacrylic acid with maleic acid. Copolymers of acrylic acid with maleic acid which contain 50 to 90% by weight of acrylic acid and 50 to 10% by weight of maleic acid are particularly suitable. Their relative molecular weight, based on free acids, is generally in the range from 5,000 to 200,000, preferably in the range from 10,000 to 120,000 and more preferably in the range from 50,000 to 100,000. It is not absolutely essential to use polymeric polycarboxylates. However, if polymeric polycarboxylates are used, detergents containing biodegradable polymers, for example terpolymers which contain acrylic acid and maleic acid or salts thereof and vinyl alcohol or vinyl alcohol derivatives as monomers or acrylic acid and 2-alkyl allyl sulfonic acid or salts thereof and sugar derivatives as monomers are preferred. The terpolymers obtained in accordance with the teaching of German patent applications DE 42 21 381 A and DE 43 00 772 A are particularly preferred. Other suitable builders are polyacetals which may be obtained by reacting dialdehydes with polyol carboxylic acids containing 5 to 7 carbon atoms and at least 3 hydroxyl groups, for example as described in European patent application EP 0 280 223 A. Preferred polyacetals are obtained from dialdehydes, such as glyoxal, glutaraldehyde, terephthal-aldehyde and mixtures thereof and from polyol carboxylic acids, such as gluconic acid and/or glucoheptonic acid.
Among the compounds yielding hydrogen peroxide in water which are used as bleaching agents, sodium perborate tetrahydrate and sodium perborate monohydrate are particularly important. Other suitable bleaching agents are, for example, peroxycarbonate, citrate perhydrates and salts of peracids, such as perbenzoates, peroxyphthalates or diperoxydodecane-dioic acid. They are normally used in quantities of 8 to 25% by weight. Sodium perborate monohydrate is preferred and is used in quantities of 10 to 20% by weight and preferably in quantities of 10 to 15% by weight. By virtue of its ability to bind free water to form the tetrahydrate, it contributes towards increasing the stability of the detergent.
In order to obtain an improved bleaching effect where washing is carried out at temperatures of 60xc2x0 C. or lower, bleach activators may be incorporated in the preparations. Examples of bleach activators are N-acyl and O-acyl compounds which form organic peracids with hydrogen peroxide, preferably N,Nxe2x80x2-tetraacylated diamines, also carboxylic anhydrides and esters of polyols, such as glucose pentaacetate. The bleach activator content of bleach-containing detergents is in the usual range, i.e. preferably between 1 and 10% by weight and more preferably between 3 and 8% by weight. Particularly preferred bleach activators are N, N,Nxe2x80x2,Nxe2x80x2-tetraacetyl ethylenediamine and 1,5-diacetyl-2,4-dioxohexahydro-1,3,5-triazine.
Suitable enzymes are those from the class of proteases, lipases, amylases, cellulases and mixtures thereof. Enzymes obtained from bacterial strains or fungi, such as Bacillus subtilis, Bacillus licheniformis and Streptomyces griseus, are particularly suitable. Proteases of the subtilisin type are preferably used, proteases obtained from Bacillus lentuis being particularly preferred. They may be used in quantities of about 0.2 to about 2% by weight. The enzymes may be adsorbed onto supports and/or encapsulated in membrane materials to protect them against premature decomposition. In addition to the monohydric and polyhydric alcohols and the phosphonates, the detergents may contain other enzyme stabilizers. For example, 0.5 to 1% by weight of sodium formate may be used. It is also possible to use proteases which are stabilized with soluble calcium salts and which have a calcium content of preferably about 1.2% by weight, based on the enzyme. However, it is of particular advantage to use boron compounds, for example boric acid, boron oxide, borax and other alkali metal borates, such as the salts of orthoboric acid (H3BO3), metaboric acid (HBO2) and pyroboric acid (tetraboric acid H2B4O7).
The function of redeposition inhibitors is to keep the soil detached from the fibers suspended in the wash liquor and thus to prevent discoloration. Suitable redeposition inhibitors are water-soluble, generally organic colloids, for example the water-soluble salts of polymeric carboxylic acids, glue, gelatin, salts of ether carboxylic acids or ether sulfonic acids of starch or cellulose or salts of acidic sulfuric acid esters of cellulose or starch. Water-soluble polyamides containing acidic groups are also suitable for this purpose. Soluble starch preparations and other starch products than those mentioned above, for example degraded starch, aldehyde starches, etc., may also be used. Polyvinyl pyrrolidone is also suitable. However, cellulose ethers, such as carboxymethyl cellulose, methyl cellulose, hydroxyalkyl cellulose, and mixed ethers, such as methyl hydroxyethyl cellulose, methyl hydroxypropyl cellulose, methyl carboxy-methyl cellulose and mixtures thereof, and polyvinyl pyrrolidone are preferably used, for example in quantities of 0.1 to 5% by weight, based on the detergent.
The detergents may contain derivatives of diaminostilbene disulfonic acid or alkali metal salts thereof as optical brighteners. Suitable optical brighteners are, for example, salts of 4,4xe2x80x2-bis-(2-anilino-4-morpholino-1,3,5-triazinyl-6-amino)-stilbene-2,2xe2x80x2-disulfonic acid or compounds of similar structure which, instead of the morpholino group, contain a diethanolamino group, a methylamino group, an anilino group or a 2-methoxyethylamino group. Brighteners of the substituted diphenyl styryl type, for example alkali metal salts of 4,4xe2x80x2-bis-(2-sulfostyryl)-diphenyl, 4,4xe2x80x2-bis-(4-chloro-3-sulfostyryl)-diphenyl or 4-(4-chlorostyryl)-4xe2x80x2-(2-sulfostyryl)-diphenyl, may also be present. Mixtures of the brighteners mentioned above may also be used. Uniformly white granules are obtained if, in addition to the usual brighteners in the usual quantities, for example between 0.1 and 0.5% by weight and preferably between 0.1 and 0.3% by weight, the detergents also contain small quantities, for example 10xe2x88x926 to 10xe2x88x923% by weight and preferably around 10xe2x88x925% by weight, of a blue dye. A particularly preferred dye is Tinolux(copyright) (a product of Ciba-Geigy).
Suitable soil repellents are substances which preferably contain ethylene terephthalate and/or polyethylene glycol terephthalate groups, the molar ratio of ethylene terephthalate to polyethylene glycol terephthalate being in the range from 50:50 to 90:10. The molecular weight of the linking polyethylene glycol units is more particularly in the range from 750 to 5,000, i.e. the degree of ethoxylation of the polymers containing poly-ethylene glycol groups may be about 15 to 100. The polymers are distinguished by an average molecular weight of about 5,000 to 200,000 and may have a block structure, but preferably have a random structure. Preferred polymers are those with molar ethylene terephthalate: polyethylene glycol terephthalate ratios of about 65:35 to about 90:10 and preferably in the range from about 70:30 to 80:20. Other preferred polymers are those which contain linking polyethylene glycol units with a molecular weight of 750 to 5,000 and preferably in the range from 1,000 to about 3,000 and which have a molecular weight of the polymer of about 10,000 to about 50,000. Examples of commercially available polymers are the products Milease(copyright) T (ICI) or Repelotex(copyright) SRP 3 (Rhxc3x4ne-Poulenc).
Where the detergents are used in washing machines, it can be of advantage to add typical foam inhibitors to them. Suitable foam inhibitors are, for example, soaps of natural or synthetic origin which have a high percentage content of C18-24 fatty acids. Suitable non-surface-active foam inhibitors are, for example, organopolysiloxanes and mixtures thereof with microfine, optionally silanized, silica and also paraffins, waxes, microcrystalline waxes and mixtures thereof with silanized silica or bis-stearyl ethylenediamide. Mixtures of different foam inhibitors, for example mixtures of silicones, paraffins and waxes, may also be used with advantage. The foam inhibitors, more particularly silicone- and/or paraffin-containing foam inhibitors, are preferably fixed to a granular water-soluble or water-dispersible support. Mixtures of paraffins and bis-stearyl ethylenediamides are particularly preferred.

Surfactant granules with an improved dissolving rate comprising alky and alkenyl sulfates