US2193637A - Carroted fur - Google Patents

Description

Patented Mar. 12, 1940 UNITED STATES PATENT OFFICE cAnno'rEn FUR Warren 0. ltlcrcier, Danbury, Conn, assignor to American Hatters and Furriers 00., Inc., Danbury, Conn., a. corporation of New York No Drawing. Application December 27, 1938,

Serial No. 248,013

10 Claims. (01. 8-112) This invention relates to carroted fur adapted of the body which the fiberscollectively compose for the manufacture of felt, and with regard to and a thickening of the body in the sense that its more specific features to hatters fur for the the finished product contains a greater number manufacture of felt hats. of fibers to the square inch, and the body is actu- One object of the invention is to provide a ally thicker in measurement at the completion 5 fast shrinking fur. Another object of the invenof the felting operation than it was when inition is to provide a quick starting fur. Another tially formed. Considering, by way of example, object of the invention is to provide a clear white the manufacture of a hat, treated fibers are defur for felting. Another object of the invention posited loosely upon a cone, and, after being wet,

W is to provideafur that shall not show any underare removed from the. cone and are found to 10 cast after dyeing. Another object of the invencling together and form a definite object which tion is to provide fur or like fibers which do not has certain dimensions. As a result of the feltdeteriorate materially over a long period of time. ing of these fibers, by the subsequent operations Another object of the invention is to provide a known as starting and sizing, the length and thoroughly oxidized fur for the manufacture of breadth of the hat body are greatly reduced, while hats. Another object of the invention is to perthe material as a whole gains in thickness and mit the manufacture of a strongly adhering felt. strength. Considering the individual fibers, this Another object of the invention is to provide a felting operation involves a relative movement fur mixture consisting in part of highly feltable among them, whereby, being initially spread out fine fur and in part of low grade filler fur havquite thinly, they are finally, at the completion 20 ing suflicient felting qualities for the manufacof the operation, densely and tightly compacted ture into a practicable hat body. Other objects together and intertwined, giving the resulting hat will be in part obvious or in part pointed out adequate strength to withstand ordinary usage. hereinafter. The exact nature of the change wrought in a The invention accordingly consists in the fur fiber by any particular carroting operation 25 I fibrous construction, combinations of elements, whereby, under the manipulation given to a and mixture of several kinds of fibers as will be body during the felting operation, it acts to exemplified hereinafter, and the scope of the produce, collectively with other fibers, the transapplication of which will be indicated in the folformation of the product above indicated, is in lowing claims. dispute, various authorities holding difierent 30 The present application is a continuation-intheories which are not entirely in harmony with part of my copending application, Serial No. each other. Although, not being certain which 720,566, filed April 14, 1934, which was in part a if any of the already advocated theories is cordivision of applications, Serial No. 532,699, filed rect, I- shall not here enter into any of them in April 24, 1931, and Serial No. 606,525, filed April detail, I may use certain terms which have a 35 20, 1932, and also a division of Serial No. 526,131, significance in connection with one or more of filed March 28, 1931, issued as Patent No. 1,955,678 such theories, but I wish it understood that my on April 17, 1934. The present application is invention is not limited by any theory, being also a continuation-in-part of my copending fully pointed out herein and distinctly. claimed 49. application, Serial No. 177,479 filed December 1, so that anyone skilled in this art can understand 1037, which was a continuation-in-part of applihow to practice the invention and will recognize cations, Serial No. 606,525 filed April 20, 1932 and what is reserved to me by the claims.

Serial No. 104,707, filed October 8, 1936. Irrespective of particular theories of carroting As conducive to a more ready and clear underand felting, it is generally understood that propstanding of the several features of my invention, erly carroted fur has the property of wetting 45 it may be noted that the subject matter thereof when immersed in the hotwater that is used in deals with fur which has been treated with a the starting and sizing operations, so-called. 0rcomposition of matter adapted to modify the dinary uncarroted fibers will not readily wet, fibers or molecules thereof in order that felt may and a carroting operation involves a cleansing be manufactured therefrom into such articles as or hydrolyzing action which affects or modifies 5o hats. The treatment of fur with a composition some constituent substance of or on the fiber so of matter such that felting qualities are imparted as to permit it to wet. A heretofore widely used thereto is known in the art as carroting. The carroting agent is mercury nitrate, so-called, felting of fur fibers (considering now eac-h sepwhich chemically speaking is supposed to be merarate unit of fur as a fiber) involves the shrinking curic nitrate and nitric acid, and this substance is recognized, when in water solution, as a hydrolyzing agent, being of a corrosive nature with an acid reaction. This heretofore widely used carrot has been known or designated in the art as mercury carrot or mercury nitrate carrot, and how the solution thereof is made is widely known. Its acid reaction or acid content has been well recognized, and, being made by dissolving mercury in nitric acid (as fur cutters almost invariably have made it up) the resultant solution includes mercury nitrate and nitric acid, whence come the mercury or mercury nitrate designations of the carroting solution and its known or recognized acidity or acid content. Fur carroted with this heretofore widely used and well known solution or carrot is known to increase in feltability with aging, and it has been assumed that this is because this mercury salt is deliquescent, thus causing the fur so carroted to absorb moisture from the air and causing a continuation of the hydrolyzing or cleansing action. I have found, in accordance with certain features of my invention, that the use of a strong oxidizing agent with a suitable hydrolyzing agent assists and accelerates the carroting that fur treated with these agents does not require aging and, as a felting substance, presents marked advantages over fibers not so treated.

The usual method of applying a carroting solution to fur is to brush it into the fur while the latter is still on the skin. In producing the article of his invention, preferably I apply a solution, hereinafter indicated, to the fur in this manner. The fur is then dried and thereafter may be removed from the skin and then or thereafter, such as after the usual blowing operation to remove the dirt or after mixing with low grade fur or hair known as filler fur, the fur becomes the commercial article intended to be secured by patent based upon this divisional application. Such fur may, immediately after having been carroted, be made into felt, but if from business or commercial considerations it is desirable to hold the fur in stock it may be kept in storage and will be found to undergo practically no deterioration over a long period. This is due to the fact that the fur is oxidized as well as hydrolyzed with an acid.

To produce the fur according to this invention, it is treated, preferably as above indicated, with an acid hydrolyzing agent and also with a strong oxidizing agent. I may use a single hydrolyzing agent such as mercury nitrate (previously identifled), or I may use two hydrolyzing agents in combination, for example chloric acid (HClOz) and sulphuric acid (H2504). For the oxidizing agent I prefer hydrogen peroxide, and I prefer hydrogen peroxide of a strength of in the neighborhood of 20 volumes of the gas to one volume of the liquid or stronger. Until comparatively recently hydrogen peroxide was commercially obtainable only in comparatively weak solutions, the so-called 3% solution being the standard commercial product. The 3% solution corresponds approximately with a solution containing 10 volumes of the oxygen gas to 1 volume of water. The active qualities of hydrogen peroxide are principally due to the fact that it liberates atomic oxygen which is nascent oxygen or oxygen in a much more chemically reactive form than the molecular oxygen such as is a constituent part of the atmosphere. The higher the concentration the atomic oxygen in the hydrogen peroxide solution the more atomic oxygen will be liberated, and I have found that, with respect to fur fibers, increasing the strength to high concentrations results in a different action upon the fur, possibly due to the breakdown of certain constituent fur substances or molecules.

To illustrate further how I employ, in coaction with one or more hydrolyzing agents, a suitable oxidizing agent, I may first note that there is available a so-called IOU-volume hydrogen peroxide containing 100 volumes of the hydrogen gas to one of water, and this substance is known as albone C. There is also a still more concentrated hydrogen peroxide containing 200 volumes of oxygen gas to one of water. I may use either of these substances as a strong oxidizing agent, and I may dilute either of them with water to obtain the exact desired concentration for a particular kind of fur or other fibers or to obtain par-- ticular qualities in such fibers. Those skilled in this art will understand that owing to variations between the characteristics of different kinds of fur, and owing to different manufacturing conditions and differences of temperature and humidity, it is desirable to have different strengths of solutions for different conditions.

I may use other oxidizing agents and as an example I may use a salt of an unstable oxygen containing radical, having a reaction like that of the hydrolyzing agent, that is an acid reaction. An example of such a salt is ammonium pcrsulphate- NH4)zSzO a. Ammonium persulphate is acid in reaction and is a hydrolyzing agent. Thus a comparatively weak solution of the main hydrolyzing agent (for example mercuric nitrate and nitric acid) may be used, and this results in the total solution containing far less of the element mercury than the widely used plain mercury nitrate solution. In fact the article according to this invention has one or more of these characteristics.

It may contain some mercury thus giving weight and body to the finished hat as compared with some prior furs having no mercury. Nevertheless it may contain less than the amount of mercury in the old and well known mercury nitrate-nitric acid (without anything else) carroted fur, for the use of a separate oxidizer eliminates the necessity of using a strong solution of mercuric nitrate. Or on the other hand it may contain no mercury at all, and nevertheless be acid in reaction thus improving its keeping qualities. And at all events it is thoroughly carroted fur right at the start, and does not have to wait for a period of so-called aging.

Another characteristic advantage of fur according to this invention is that it has a strong tendency to felt and a strong tendency to stop felting once the felting process has proceeded to a definite limit. This I may term stability, and it has been the characteristic of some prior furs. for example the old mercury nitrate carroted fur. that the sizing might proceed beyond the point where the desired size of hat body'was reached. If mercury nitrate is used for the hydrolyzing agent, nevertheless the quantity of mercury present need not be so large as to cause the fur to be poisonous to hat manufacturing operatives.

In pointing out several different embodiments of this present invention it must be kept in mind that throughout the various embodiments there runs the main characteristic of fur which is both hydrolyzed with an acid agent and oxidized, and that in the manufacture of hats, for example, there are many different styles and weights to be considered and various types of manufacturing operations to be borne in mind,.as well as the unexplained desires of hat manufacturers, so that any one of the embodiments may be the most practical form of the invention for a particular style and size of hat or for the needs of a particular hat manufacturer.

Referring again to the ammonium persulphate, it is an oxidizing agent, and furthermore having little tendency entirely to liberate and lose its atomic oxygen except in the presence of something which can combine with the oxygen; i. e. to be oxidized, it may be kept standing uncovered longer than a solution containing hydrogen peroxide, for example. Also, the oxidizing action proceeds upon the fur until practically all of the oxygen is liberated that can be obtained from the persulphate, as little of it escapes to the air. This characteristic results in a carroting solution that will duplicate results under different conditions of temperature, humidity and elapsed time for the carroting action, and permits the use of an oxidizing agent which is relatively weak.

Referring again to the examples of acid hydrolyzing agents, chloric acid is a strong acid which is particularly adaptable for use where a strong hydrolyzing is wanted. In order to obtain this acid, preferably I place a quantity of barium chlorate in sulphuric acid, and by using an excess of sulphuric acid over what partakes in the reaction representedby the chemical formula Ba(BlO3)z+I-12SO4 produces 2HClO3+BaSO4 I secure an additional strong hydrolyzlng agent in the solution. This method of obtaining two strong hydrolyzing agents has several advantages, among them being that the sulphuric acid is the only acid to be kept on hand, and another that the ingredients of the solution are inexpensive and readily procured.

As illustrative embodiments of the fur of the invention, I note that it is desirably rabbit or coney fur or beaver fur or the like and may be pure fur so-called, or have a mixture of inferior fur or hair so-called, or even shredded hat bodies, all of which is designated under the general term fillerjand that the pure fur thereof at least has been treated or carroted with one 01 the solutions indicated below:

To parts, by volume, of Albone C, which is, as above stated, 100-volume H202, add 80 parts, by volume, of water (thus reducing the H102 to 20-volume strength), and to the solution so obtained, add 100 parts, by volume, of 3 deg. Baum solution of mercury nitrate.

2. To 1 part, by volume, of Albone C which is,-as above stated, 100-volume H202, add 1 part, by volume, of 20 deg. Baum solution of mercury nitrate.

3. To 1 part, by volume, of ZOO-volume H202, add 1 part, by volume, of deg. Baum solution of mercury nitrate.

(In the above three examples mercury nitrate means carroters mercury nitrate as heretofore explained.)

4. To parts, by weight, of metallic mercury, add 100 parts, by weight, of nitric acid deg. Baum. The resultant mercuric nitrate and nitric acid should then be diluted by adding water until it tests about 6 deg. Baum. To this is added an equal quantity of a solution of am-- monium persulphate testing about 6 deg. Baum.

5 Mercury nitrate and nitric acid solution havingthat proportion of mercury indicated in Example 4 is reduced by adding water until it tests about 12 deg. Baum. This is then added to an equal quantity of solution of ammonium persulphate testing about 14 deg. Baum.

6. Setting apart 150 parts of barium chlorate, 12 gallons of sulphuric acid of 66 deg. Baum, which weighs about 184 pounds, and '75 gallons of water, dissolve the barium chlorate by adding to it as much of the water as is required completely to dissolve it, then add the sulphuric acid to the remaining water, and when the reaction is no longer violent, add the dissolved barium chlorate to the diluted sulphuric acid. The resulting solution has a specific gravity of approximately 15 deg. Baum. This solution is then added to an equal part by volume, of ZOO-volume H.202.

7. The 15 deg. Baum solution of barium chlorate and sulphuric acid, as set forth'ln Example 6, is added to an equal quantity, by volume, of 100- volume H202, know as "Albone C.

8. A solution of barium chlorate and sulphuric acid prepared as in example 6 .but diluted with water until its specific gravity is 3 deg. Baum, is added to an eual quantity, by volume, of 20- volume H202.

9. To 5 parts by volume of 100 volume H202, add 1 part by volume of mercury carrot, 6 deg. Baum and 1 part by volume of ammonium persulfate 6 deg. Baum.

10. To 1 parts 100 volume H202 add 1 part by volume mercury carrot 6 deg. Baum and 3 parts by volume of ammonium persulfate 9 deg. Baum.

11. To 1% parts 100 volume H202 add 1 part by volume mercury carrot, 10 deg. Baum and 3 parts by volume ammonium persulfate 12 deg. M

'of the mercury nitrate is from. 7 deg. to 15 deg.

Baum. Within these ranges I achieve very excellent results, using 10 parts, by volume, of hydrogen peroxide to 1 part, by volume, of mercury nitrate, and 10 parts, by volume, of mercury nitrate to 1 part, by volume, of hydrogen peroxide, and intermediate proportions of these two I agents.

By mercury nitrate I meanand intend the known carroting substance passing by that name, and mercury nitrate, as it is known and understood in the art of carroting fur, is acid in reaction and, I am informed and believe, consists chemically largely of mercuric nitrate Hg(NO3)2 and nitric acid-HNOz. At all events it is and was made by completely dissolving mercury in nitric acid. Of course the substances are in an ionic state; water is present or added, and there may be other substances present. Among the latter I believe some mercury oxide HgO, to be formed and acts to a certain extent as an oxidizing agent. The action of the oxygen in this oxygen carrier (which, however, is substantially insoluble and does not release any atomic oxygen) might produce a mild oxidizing action upon the the strong oxidizing action of the atomic oxygen of any of the oxidizing agents herein indicated when used directly with any of the acid hydrolyzing agents heretofore indicated. This is the result of certain coactions that take place between the acid hydrolyzing agent and the oxidizing agent including atomic-oxygen. Certain advantages follow from the use of an acid hydrolyzing 'agent by reason of the fact that besides hydrolyzing the constituents of the fur fibers it coacts with and acts directly upon the atomic oxygen of the oxidizing agent to multiply the oxidizing power thereof. In this connection it may be noted that a fur fiber is of such a complex nature that different constituent parts of it are affected by different specific agents and different strengths of the same agent. More specifically I may point out that it is now generally considered that a fur molecule is an amino body composed of the union of a basic group with an acidic group and therefore can be hydrolyzed either with an acid or with a base, but the action of an acid upon an atomic oxygen containing oxidizing agent is far different from that of a base. Thus I believe that there is some action, interaction, or joint action, among, by or between the several elements, ions, compounds or radicals of the carroting solution used to form the fur of this invention as well as joint and several action upon the fur molecules or fibers all producing in the fur a much different article, so far as the manufacture of hats is concerned, than any fur heretofore known.

Certain marked advantages are present in the fur of the invention. For example it is possible to make a very tight felt with fur made as herein described and the fur adheres very strongly thus making a strong felt. I have found that the fur of the invention starts to felt very rapidly, meaning that in the so-called starting operation the fibers go together quickly and shrinking proceeds with great rapidity. This fast shrinking quality continues during the so-called sizing operation. It is understood among those skilled in this art that the shrinking qualities are important from the manufacturing standpoint; a fur which shrinks rapidly may be turned into completed articles more quickly and with less eifort on the part of the operatives than fur not having such qualities. Nevertheless; when a piece of felt made of fur of the invention arrives at the size desired, it stops felting and attains a stability. The shrinking and feltable qualities of'fur may be plotted against time, and it will be found that some furs start slowly and accelerate towards the end of the process so that it is diificult to hold them at the correct size. The desired property of fur in this respect is' to have it start quickly and felt rapidly up to finished size and then attain stability, and fur treated according to the invention has this property.

A very important characteristic of fur according to the invention resides in the fact that it is not discolored. If white rabbits fur is used prior to the treatment described it remains white. Fur carroted in accordance with the old mercury nitrate process was discolored; when artificial heat was used for drying, the fur was of the color of a carrot (whence the word carroting). I am not certain in what manner the use of an oxidizing agent having atomic oxygen acts to prevent discoloration, but at all events the result is marked, and fur treated in accordance with the invention can successfully be dyed into the lightest shades,something which cannot be achieved with mercury nitrate carroted fur.

My novel carroted fur which is produced by any of the several types of carrots previously described and which is therefore acid in reaction has, among others, the very important characteristics of natural color, i. e. being free from any colored reactionproduct as well as rapid starting and felting. These may be identified by reactions of the fibres to certain tests. For example, the fibres of my improved carroted fur product have unusual dyeing characteristics. For example they have 'a distinctive affinity for and take a heavy infusion of the direct dyestuff Benzo-purpurin 4-B (color index No. 448) when immersed therein at room temperature for one .hour and of the basic component of Wrights stain, a mixture of methylene blue (basic) and eosin (acid) when immersed therein for a few seconds at boiling temperature. The Wrights stain is prepared as explained in detail in The National Formulary, 6th edition, 1935, pages 447-8.

My improved fur also responds in a distinctive manner to alkali swelling tests wherein the carroted fibre of the fur is subjected to N/10 caustic soda. This test discloses that under such conditions, the diameter of the fibres of my improved fur, as observed under the microscope, increases not less than 35% over their entire length and more than 100% over the portion from midway of their length to their outer tip ends, i. e. those ends furthest from the skins before cutting. This shows a substantial carroting effect throughout the length of the fibre and it is particularly important to note that there is substantially carroting between the midportion of the fibre and the butt end thereof, i. e. the end adjacent the skin before cutting.

Furs carroted according to the several methods herein disclosed are also distinguishable in that the fibres have a characteristic stretchability under longitudinal stress when immersed in water at 50 C. With a given load the stretch in such a fibre increases from butt to tip, that at the tip being at least twice that at the butt. This capacity for stretching under the test conditions stated indicates a peculiar or distinctive disruption or alteration of the fibre structure, the efi'ect of which is observable under conditions approaching those to which the fibres are subjected in felting. The water temperature of 50 0., here indicated for test, is specified because it approximates the nearest approach to felting temperature at which one available type of test apparatus could be employed. Felting usually takes place in moisture (water) at around boiling temperature.

. It will be apparent that the foregoing tests disclose novel properties of my product in regard to acidity, sensitivity to dyestuffs, alkali swelling and stretchability under given test conditions. The exact functions of these peculiar properties in relation to the outstanding starting and felting characteristics of my improved fur are not fully understood; but their values correspond approximately to values of said starting and felting qualities expressed in time units.

Many other advantages inhere in the invention. Fur of the invention may be dried either with or without artificial heat, and may be used immediately after being carroted or at a later time. It is found that a newly formed hat bat of fur treated according to the invention will hold air, thus showing that the fibers started to adhere and shrink immediately they were wet. Moreover, owing to the fast shrinking and strongly adhering qualities of this fur, a large amount of per se non-feltable, otherwise known as filler, fur, may be mixed in, and in fact large quantities of fiber other than fur may be mixed with fur of the invention, resulting in a good quality of felt at low cost. I have been able to use as high as 50% of filler fur obtaining good results and the resultant product is itself part of my invention. Also, hat bats or bodies made from fur of the invention as well as the carroted fur itself, with or without filler, may be stored or carried in stock for substantial periods of time adequate to meet the various needs or conditions met with in the fur preparing and felt hat manufacturing arts, without detrimental deterioration and without harmful chemical or other change, except that if a persulfate is used or other reagent which yields up free oxygen over a substantial period after completion of the carroting step, the fur may have a tendency to become brittle unless it is kept dry during storage. Fur of the invention may be dyed in the usual manner and it is found there is no undercast to such dyed fur.

From the above it will be readily seen that there in herein provided an article of manufacture which attains the objects of this invention, including many distinct, practical and useful advantages. As various possible embodiments might be made of the above invention, and as many changes might be made in the embodiments abo e set forth, without departing from the scope of the invention, it is to be understood that all matter hereinbefore set forth is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. As a new article of manufacture, the herein described fur in feltable condition, the individual fibers thereof being normally acid in reaction and having a pronounced gelatinous condition at their tip ends, said fur being further identified in the following manner: when the fur is immersed in a water bath at boiling temperature containing a mixture of methylene blue which is basic in reaction and eosin which is acid in reaction, the fur exhibits a marked preferential aflinity for the methylene blue; when the fur is immersed in a water bath containing the direct dyestuff Benzopurpurin 4-33 for one hour at room temperature, the fur exhibits a distinct aflinity for this dyestufi and takes a heavy infusion thereof; when the individual fibers are subjected to the action of N/IO caustic soda they increase in diameter along substantially their entire lengths; and when the individual fibers are stressed longitudinally while in water at 0., they stretch along substantially their entire lengths in increasing amounts from butt to tip.

2. As a new article of manufacturaiur in feltable condition, acid in reaction, and including fur fibres substantially carroted between midway of their lengths and their butt ends, and, when in undyed condition, having no colored reaction products.

3. As a newtarticle of manufacture, fur in feltable condition, acid in reaction, and including fur fibres having no colored reaction products and further characterizedin that said fibres swell and thereby increase in diameter along substantially their entire lengths when they are subjected to the action of N/lO caustic soda.

4. Carroted fur or the like, acid in reaction, and when immersed in a mixture of methylene blue which is basic in reaction and eosin which is acid in reaction exhibits a preferential aifinity for the methylene blue.

5. Carroted fur or the like, acid in reaction, and exhibiting a distinct aflinity for and will take a heavy infusion of the direct dyestuff Benzopurpurin 4-3 when immersed therein for one hour at room temperature.

6. A fast-shrinkin quick-starting carroted fur,-

acid to indicators, containing the reaction products of the natural fur, hydrogen peroxide, nitric acid and mercuric nitrate and being substantially free from permanent stain from the carroting.

7. A fast-shrinking, quick-starting carroted fur, acid to indicators. containing the reaction prodnets of the natural fur, hydrogen peroxide, sulfuric acid and chloric acid and being substantially free from permanent stain from the carroting.

8. A fast-shrinking, quick-starting carroted fur, acid to indicators, containing the reaction prodnets of the natural fur, a per-salt and an acid corroting agent and being substantially free from permanent stain from the carroting.

9. A fast-shrinking, quick-starting carroted fur, acid to indicators, containing the reaction products of the natural fur, a persulfate and an acid carroting agent and being substantially free from permanent stain from the carroting.

10. A fast-shrinking, quick-starting carroted fur, acid to indicators, containing the reaction products of the natural fur, ammonium persulfate, nitric acid and mercuric nitrate and being substantially free from permanent stain from the carroting.

WARREN C. MERCER.

CERTIFICATE OF CORRECTION. Patent No. 2,195,657. a March 12, 191p.

WARREN c. nERcI R, It is'hereb; certified that error appears in the'printed specification of the above numbered patent requiring correction as follows: Page 2, first column, line 52, for the word "his" read. --this--; page 5, first column,

line 25, after "hydrolyzing" insert -agent--; line 51, in the formula, for

"Ba(BI0 read --Ba(CIO same page, second column, line 19, example 7, for "know" read --known--; line 25, example 8, for "anal" read --equal--; page 1 second column, line 3 7, for'the word "substantially" read --substantial--;page 5', first column, line 28 for "in" read --isand second column, lin 15, claimB, for "corrotihg" read --carroting--; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 114th day of MaY AQ D. 1910.

Henry Van Arsdale;

(Seal) Acting Commissioner of Patents.