US3496112A - Fluorescent dye compositions - Google Patents

Description

United States Patent 3,496,112 FLUORESCENT DYE COMPOSITIONS Seymore Goldwasser, Teaneck, N.J., and Ralph R. Sepulveda, Bronx, N.Y., assignors to Lever Brothers Company, New York, N.Y., a corporation of Maine No Drawing. Filed July 24, 1967, Ser. No. 655,340 Int. Cl. C09k 1/02; D06p 1/88 US. Cl. 252301.2 7 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to fluorescent dye compositions and more particularly to fluorescent dye compositions especially adapted for imparting increased fluorescence or optical brightness or whitening to both hydrophilic or hydrophobic fibers.

Anionic fluorescent dyes are known to be capable of brightening or whitening cotton fabrics because of the hydrophilic nature of the cotton fibers. However, anionic fluorescent dyes are incapable of brightening or whitening fine fabrics, such as those composed of Dacron, Orlon or the like, because such synthetic fibers are hydrophobic in character.

Moreover, when anionic fluorescent dyes are blended with fabric softening cationic nitrogenous compounds in an attempt to formulate a composite optical brightening and fabric softening composition, the anionic fluorescent dye and the fabric softening cationic nitrogenous compound form a complex with one another. The resultant complex is incapable of brightening or whitening either hydrophilic fibers, such as cotton, or hydrophobic fibers, such as Dacron, Orlon and the like.

It is, therefore, the principal object of the present in' vention to provide a composite fabric softening and brightening composition containing an anionic fluorescent dye and a fabric softening cationic nitrogeous compound, and yet which will provide a brighteing or whitening to both hydrophilic and hydrophobic fibers.

The fluorescent dye compositions of the invention which are especially adapted for imparting increased fluorescence or optical brightness to both hydrophilic and hydrophobic fibers contain three essential components. These three components are an anionic fluorescent dye, a fabric softening cationic nitrogenous compound capable of forming a complex with the dye, and an electrolyte, i.e., a dissociable salt capable of having a salting out effect upon the complex. In the compositions, the amount of cationic nitrogenous compound is in excess of the amount of anionic fluorescent dye. Thus, the compositions contain from about 0.01% to about 0.7% by weight of the anionic fluorescent dye, from about 2% to about 20% by weight of the fabric softening cationic nitrogenous compound capable of forming a complex with the dye and from about 8% to about 89% by weight of the electrolyte.

The anionic fluorescent dyes are well-known materials. Typical representative examples thereof include disodium N:N'-bis- (2-diethanolamino-4-phenylamino-1 :3 :5 -tri azyl-[6] )-4:4-diamino stilbene 2:2-disulfonate, disodium N:N-bis-( 2-morpholino-4-phenylamino-1 :3 :S-triazyl- [6])-4:4-diamino stilbene 2:2'-disulfonate, disodium N:N-bis-(2,4 diphenylamino 1:3:5-triazyl-[6])-4:4'- diamino stilbene 2:2-disulfonate, disodium 4,4-bis[4- anilino-6-(N-methyl-N-hydroxyethylamino) S-triazin-2- ylamino]stilbene disulfonate, disodium 4,4-bis-(4-phenyl-2,1,3-triazole-2-yl) stilbene disulfonate, disodium 4,4- bis[4-anilino-6-(N-2-methyl 2 hydroxyethyl-amino)-striazin-2-ylamino]stilbene disulfonate and sodium 2-(stilbyl-4")-naphtho-1,2':4,5) 1,2,3 triazole-2"-sulfonate. Other suitable anionic fluorescent dyes are disclosed in South African Patent No. 66/2892 and in United States Patent Nos. 2,376,743, 2,612,501, 2,762,801, 2,784,183 and 3,012,971.

The cationic nitrogenous compound capable of forming a complex with the dye must have fabric softening properties. Such fabric softening cationic nitrogenous compounds are well known to the art. Preferably, such compounds are the fabric softening cationic quaternary ammonium compounds, e.g., those containing two shortchain alkyl groups and two long-chain alkyl groups; or two short-chain alkyl groups, a long-chain alkyl group and an aralkyl group; or a short-chain alkyl group, a short-chain hydroxylated alkyl group, a long-chain hydroxylated alkyl group and an aralkyl group; or two shortchain alkyl groups, a long-chain alkyl grou and a shortchain hydroxylated alkyl group. The anionic portion of such compounds, as is well known, can be halides, sulfates, alkyl sulfates, and acetates. Typical representative, but non-limiting, examples thereof include dimethyl dicoco ammonium chloride, bromide, iodide, sulfate, methyl sulfate and acetate; dimethyl distearyl ammonium chloride, bromide, iodide, sulfate, methyl sulfate and acetate; dimethyl dihydrogenated tallow ammonium chloride, bromide, iodide, sulfate, methyl sulfate, and acetate; dimethyl N-alkyl (C -C benzyl ammonium chloride, bromide, iodide, sulfate, methyl sulfate and acetate; N- methyl-N-(2-hydroxyethyl) N (2-hydroxydodecyl)-N- benzyl ammonium chloride, bromide, iodide, sulfate, methyl sulfate, and acetate; and N,N-dimethyl-N-dodecy1- N-(Z-hydroxyethyl) ammonium bromide, chloride, iodide, sulfate, methyl sulfate and acetate.

Other representative well-known fabric softening nitrogenous compounds include the reaction products of higher fatty acid with hydroxyalkyl alkylene diamines, C C amide imidazoline salts, alkylamido alkylene pyridinium chloride, l-(2-alkylamido ethyl)-2-alkyl imidiazoline salts and the salts of heptadecyl imidazoline. Further suitable fabric softening cationic nitrogenous compounds are set forth in American Dyestuff Reporter, Jan. 28, 1957, pages 41 et seq.

The electrolyte is a dissociable salt, either organic or inorganic, capable of having a salting out effect upon the anionic dye-cationic nitrogenous compound complex. Typical of such compounds which can be used in the compositions of the invention are the sodium, ammonium, potassium, calcium and magnesium chlorides, tripolyphosphates, sulfates, pyrophosphates, carbonates, silicates, citrates, acetates, formates, propionates, tartrates, malonates and the like.

The three component compositions described above, when added to an aqueous medium, form an unstable dispersion and cause relatively uneven brightening or whitening of hydrophobic and hydrophilic fibers. It is, therefore, preferred that the compositions contain a fourth component which is an anionic dispersant or surface active agent having a dissociation constant lower than that of the anionic dye-cationic nitrogenous compound complex. The presence of the anionic dispersant in the compositions enables the compositions to be blended with water so as to form more stable dispersions and to give greater evenness in the brightening or whitening of hydrophobic or hydrophilic fibers.

An anionic dispersant may be present in the compositions in an amount from 0% to about 15% by weight.

Representative examples of such anionic dispersants are sodium toluene sulf-onate and phosphonate, linear sodium dodecyl benzene sulfonate and phosphonate, linear sodium pentadecyl benzene sulfonate and phosphonate, sodium benzene sulfonate and phosphonate, sodium xylene sulfonets and phosph-onate, and the sodium soaps of fatty acids have 6 to 10 carbon atoms, such as sodium caproate, sodium caprylate and sodium caprate.

It has been found that the dispersant must be anionic in nature and that non-ionic dispersants aflect the anionic dye-cationic nitrogenous compound complex in such a manner that it prevents the whitening of hydrophobic fabrics, such as Dacron or Orlon.

The compositions described above containing at least three or four components may be prepared by blending the components thereof together in any order to form a powder, flake, granular or other dry product. The anionic dispersant component should dissolve after the electrolyte dissolves. This can be achieved, for example, by encapsulating the anionic dispersant with a slowly water soluble film forming material. These dry compositions may be used by blending one part thereof with 400 parts of water to form an unstable or stable dispersion and the dispersion then applied to the hydrophobic or hydrophilic fibers.

Aqueous usage concentrations of the above compositions contain from about 0.25 p.p.m. to about 10 p.p.m., preferably about 2 p.p.m., of the anionic fluorescent dye; from about 0.005% to about 0.05% by weight, preferably about 0.013% by weight, of the fabric softening cationic nitrogenous compound capable of forming a complex with the dye; from about 0.02% to about 0.5% by weight, preferably about 0.1% by weight, of the electrolyte; from to an amount equimolar with the cationic nitrogenous compound, preferably about 0.013% by weight, of the anionic dispersant for the complex; and the substantial balance to 100% by weight of water.

It has been found that when aqueous dispersions are prepared of the compositions which contain the anionic dispersant, the order of addition of the components to the aqueous medium is critical in order to obtain high brightening or whitening of hydrophobic and hydrophilic fibers.

It is thought that the mechanism for the obtention of improved brightening or whitening of hydrophobic and hydrophilic fibers by the compositions of the invention involves the forming and salting out of a cationic nitrogenous compound-anionic fluorescent dye complex precipirate by means of the electrolyte, which precipitate coats the surface of the fiber resulting in an outer coating of the dye.

Illustrative compositions of the invention were tested by the following standard dyeing test procedure.

Dyeing test procedure Each ingredient was added from a master solution which had been made up at concentrations sufliciently high to allow 10 ml. aliquots of each to be taken; the volume was then brought to 100 ml. with distilled water. 0.013% by weight of a cationic nitrogenous compound, 2 p.p.m. of an anionic fluorescent dye, 0.1% by weight of an electrolyte, 0.013% by weight of an anionic dispersant and 100 ml. of water, either distilled or having a hardness of 180 p.p.m. (2:1 CaCl :MgCl represent the final composition. Dyeings were carried out using 1 gm. swatches of cloth in 100 ml. of dye solution at 120 F. and agitated for 20 minutes in a Shake-O-Meter. The cloths were rinsed twice in distilled Water, air dried (in the dark) at room temperature, ironed and read in a Beckman DU-Z Spectrophotometer fitted with a reflectance attachment and adapted for fluorescence measurements by use of a Wratten 2-B blocking filter. The fluorescence stimulating wavelength was 380 mu for cloths of hydrophobic fibers and 360 mu for cloths of hydrophilic fibers. In this test, the higher the fluorescence (F) reading, the greater the fluorescence or optical brightness.

Using the above test procedure, a number of comparar tive dyeings were made wherein the anionic fluorescent dye was disodium N:N'-bis-(2-morpohlino4-phenylamino 1:3:5-triazyl-[6])-4:4-diamino stilbene 2:2-disulfonate, the electrolyte was pentasodium tripolyphosphate, the anionic dispersant was linear sodium dodecyl benzene sulfonate and the cationic nitrogenous compound was varied as set forth in Table I below which gives the fluorescence values in F units.

TABLE I F units on Dacron F units on Orlon Average of F units on Distilled Hard Distilled Hard both Dacron Nitrogenous compound water water water water and Orlon Example N o 1 None 2.6 3.3 3.0 2 Tetramethyl ammonium chloride 2. 6 2. 7 3. 0 3. 6 3. 0 3-. Tetrabutyl ammonium bromide 2. 5 2. 3 3. 5 4. 6 3. 2 1 Trimethyl pentyl ammonium bromide. 2. 5 2. 4 2. 8 4. 2 3.0 5-.-" Trimethyl heptyl ammonium bromide 2. 3 2. 3 3. 2 4. 2 3. 0 6.- Trimethyl dodecyl ammonium bromid 4. 4 4. 3 5. 7 6. 5 5. 2 7 Trimethyl cetyl ammonium bromide-.. 4. 7 3. 7 5. 6 6. 6 5. 2 8 Trimethyl tetrat-ricontyl ammonium bromide 2. 7 2. 7 3. 0 8. 7 3. U 9 Triinethyl benzyl ammonium chloride 2. 6 2. 6 3. 6 4. 2 3. 2 10- Dimethyl dicoco ammonium bromide. 16. 2 12. 4 14. 9 14. 8 14. 6 1L Dirnethyi Distearyl ammonium chloride (i 2 7.0 18. 9 18. 0 12. 5 12". Dimethyl dihydrogenated tallow ammonium chloride. 8. 5 14. 0 16. 3 12. 9 12. 9 13 Dimethyl N-alkyl (C rcle) benzyl ammonium ohlorid g 10. 7 14. 9 5. 3 9. s 10. 2 14 N-methyl-N-(Z-hydroxyethyl)-N-(2-hydroxy-dodecy1)-N-beuzy1 am- 8. 5 10. 6 9. 2 9. 3 9. 4

monium chloride. 15 N,N-dimethyl-N- odeeyl-N-(Z-hydroxyethyl) ammonium bromide... 17. 2 15. 7 11. 2 14.0 14. 5

In Table I above, Examples 1-9 are comparative fluorescent dye compositions, While Examples 10-15 are illustrative of the fluorescent dye compositions of the invention. It will be noted from the data for comparative Example 1 which contained an anionic fluorescent dye but did not contain any cationic nitrogenous compound, that the average fluorescence reading for Dacron and Orlon cloth was very low, namely, 3.0. 7

The cationic nitrogenous (quaternary ammonium) compound present in the comparative compositions of Examples 2 through 9 contained four short-chain alkyl groups (Examples 2-3) or three short-chain alkyl groups and one long-chain al y gro p (Examples 4-8) or three short-chain alkyl groups and an aralkyl group (Example 9) and hence had little or no fabric softening properties. The average fluorescence readings for these eight comparative compositions were all quite low, ranging from a low of 3.0 showing no improvement over Example 1 to a high of only 5.2.

The cationic nitrogenous (quaternary ammonium) compound used in the compositions of Examples 10-15 contained two short-chain alkyl groups and two longchain alkyl groups (Examples 10-12) or two short-chain alkyl groups, a long-chain alkyl group and an aralkyl group (Example 13) or a short-chain alkyl group, a shortchain hydroxylated alkyl group, a long-chain hydroxylated alkyl group and an aralkyl group (Example 14) or two short-chain alkyl groups, a long-chain alkyl group and a short-chain hydroxylated alkyl group (Example 15) and hence had fabric softening properties. The average fluorescence readings for these six compositions illustrative of the invention of Examples 10-15 were appreciably better than those for comparative Examples 1-9, ranging from 9.4 to 14.6.

Following the test procedure given hereinbefore, various fluorescent dye compositions were compared in the treatment of both Dacron and Orlon cloth. These compositions differed from one another in that the cationic nitrogenous compound thereof and the anionic fluorescent dye thereof were varied. The electrolyte and anionic dispersant were as given for Examples 1-15. The results of these comparative tests are set forth in Table II, below wherein opposite each cationic nitrogenous compound the first line is the fluorescence readings in F units for Dacron cloth while the second line is the fluorescence readings in F units for Orlon cloth. The last column of data is the average of F units on both Dacron and Orlon. In Table II below the anionic fluorescent dyes have been coded as follows for ease in presentation of the comparative data.

(A) disodium N:N'-bis-(2-diethanolamino-4-phenylamino-1:3:5-triazyl-[6]-4:4'-diarnino stilbene 2:2-disulfonate, i.e., Calcofluor White M2R.

(B) disodium N:N-bis-(2-morpholino-4-phenylamino-1:

3:5-triazyl-[6])-4:4'-diamino stilbene 2:2'-disulfonate,

i.e., Calcofluor White RC.

(C) disodium 4,4'-bis-[3-anilino-6-(N-methyl-N-hydroxyethylamino)-s-triazin-2-ylamino] stilbene disulfonate, i.e., Tinopal 4BM.

(D) disodium N:N-bis-(2,4-diphenylamino-1 :3 :S-triazyl- [6] )-4:4-diamino stilbene 2:2'-disulfonate, i.e., Calcofluor White MR.

(E) disodium 4,4-bis-(4-phenyl-2,1,3-triazole-2-yl) stilbene disulfonate, i.e., Blancophor CA 4317.

(F) disodium 4,4'-bis [4-anilino-6-( N 2 methyl-Z-hydroxyethyl-amino)-s-triazin-2-ylamino] stilbene disulfonate, i.e., Leucophor BS.

Example 20 while the best overall anionic fluorescent dye was that coded B.

The criticality of the order of addition of the components in forming the aqueous compositions of the invention which contain an anionic dispersant is shown by the data set forth in Table III below. Following the dye testing procedure given above, dyeings were made on Dacron fabric with compositions wherein the order of addition of components was varied as given in Table III below. In this table the following abbreviations have been used:

TPP is pentasodium tripolyphosphate (the electrolyte).

LAS is linear sodium pentadecyl benzene sulfonate (the anionic dispersant).

QUAT is distearyldimethyl ammonium chloride (the fabric softening cationic nitrogenous compound).

H O is water.

Dye is sodium 2-(stilbyl-4")-(naphtho-1',2': 4,5 )-1,2,3- triazole-2-sulfo.nate, i.e., Tinopal RBS (the anionic fluorescent dye).

NaCl is sodium chloride (the electrolyte).

TABLE III Order of addition F value 3. 4 2. 4 3. 4 3. 4 3. 5 PP, QUAT, Dye, LAS, H2O 2. 8 27 QUAT, Dye, TPP. LAS, H20 8.3 28 UAT, Dve, NaCl, LAS, H O 15.6

In the above Table III, Examples 21 through 26 are comparative process examples while Examples 27 and 28 are illustrative of the process of the invention. The data in the above table for Examples 27 and 28 illustrate the importance of the order of addition to form an aqueous dispersion when an anionic dispersant is present and these data further indicate that for eflicient brightening or whitening, the anionic fluorescent dye and the cationic nitrogenous compound must form a complex which is then salted out by the electrolyte. The aqueous compositions of Examples 21-24 resulted in a much too dilute initial system for the forming of the complex. The order of addition for Example 25 wherein the anionic dispersant (LAS) was added before the electrolyte (TPP) allowed the anionic dispersant to tie up the cationic nitrogenous compound (QUAT) or break up the complex before it was salted out. The order of addition for comparative Example 26 shows that the addition of the electrolyte (TPP) prior to the cationic nitrogenous compound (QUAT) and the anionic fluorescent dye (dye) also inhibited the formation of the complex. However, the order of addition for Examples 27 and 28 illustrating the process of the invention resulted in highly satisfactory TABLE II Example No. Nitrogenous compound A B C D E F Average 13.4 7.0 4.4 8.6 3.1 2.9 16 Dimethyl distearyl ammonium chloride 1&0 3.8 w M 34 7.5

4.1 14.0 4.3 9.3 1.6 2.7 17 Dimethyl dihydrogenated tallow ammonium chloride 2 12 9 7 8 1 6 6 6-1 20.0 14.9 4.8 2.4 2.6 2. 6 1s Dimethyl N-alkyl (Cm-Cm) benzyl ammonium chloride M 6 M as 7. 4 8.2

. 10. 4.4 4.4 1.6 3.1 19 N-methyl-N-(2-hydroxyethyl)-N-(2-hydroxy-dodecyl)-N-benzyl ammOmUm chlonde. Z ,3 6 M 4 7 5 5.6 6. 5 15. 7 l1. 3 14. 8 11.1 20. 2 11 7 20 N,N-dunethyl-N-dodecyl-N-(Z-hydroxy-ethyl) ammonium bromide 6 14. 0 2 10' 5 8 2 In Table 11 above, Examples 16-20 are representative 7t) fluorescence values. These latter two examples also illusfiuorescent dye compositions of the invention. The data therein illustrate the effect of varying the fabric softening cationic nitrogenous compound and the anionic fluorescent dye components. The data indicate that the trate that the electrolyte can be varied, since the use of eTther sodium chloride or pentasodium tripolyphosphate gave satisfactory fluorescence values.

The effect of varying the nature of the anionic best overall cationic nitrogenous compound was that of dispersant using the above dyeing test procedure on TABLE IV compositions of the invention are capable of brightening or whitening a variety of hydrophilic and hydrophobic fibers, including Orion, which has previously been impossible to whiten in the laundering process or needed very selective Anionic dispersant Sodium toluene sulfonate Sodium linear dodecylbenzene sulionate.

32: Sodium linear pentadecylbenzcne Sultanate 33 Sterox LN (e nonionic alkyl-ethylene oxide condensate) From the data set forth above in Table IV, it is clear that the compositions of the invention need not contain an anionic dispersant in order to achieve high brightening or whitening as shown by the P value of 13.3 for Example 29 wherein the composition was free from an anionic dispersant.

Examples 30-32 show that as the chain length of the anionic dispersant is increased, the fluorescence values obtained for the compositions is decreased. Moreover, comparative Example 33 illustrates the fact that the use of a nonionic dispersant, rather than an anionic dispersant, affects the anionic dye-cationic nitrogenous compound complex in such a manner that it prevents any Dacron whitening by the system.

The data presented below in Table V illustrate the effect of varying the amounts respectively of the anionic fluorescent dye (dye), the electrolyte (TPP) and cationic nitrogenous compound (QUAT) upon the whitening of Dacron cloth using the above dyeing test procedure modified as to the amounts of components. The components of the composition were the same chemically as those used in Example 31 above. Therefore all of the examples in Table V also contained 0.013% of sodium linear dodecylbenzene sulfouate as the anionic dispersant.

and expensive dyes to achieve this result.

Other standard test procedures have demonstrated the fabric softening property of the composite fabric softening-brightening compositions of the invention.

The compositions of the invention can contain other compatible adjuvants, such as perfumes, germicides, colorants and the like.

It will be appreciated that various modifications and changes may be made in the composition and process of the invention, in addition to those set forth above, by those skilled in the art, and accordingly the compositions and process of the invention are to be limited only within the scope of the appended claims.

What is claimed is:

1. A fluorescent dye composition especially adapted for imparting increased fluorescence or optical brightness to both hydrophilic and hydrophobic fibers consisting essentially of from about 0.01% to about 0.7% by weight of an anionic fluorescent dye, from about 2% to about 20% by weight of a fabric softening cationic nitrogenous compound capable of forming a complex therewith, and from about 8% to about 89% by weight of a dissociable salt capable of having a salting out effect upon the complex.

TABLE V Amounts of components F value Example No.:

34. 1 p.p.m. dye plus 0.1% TPP plus 0.013% QUAT- 6.6 2 p.p.m. dye plus 0.1% TPP plus 0.013% QUA'I- 11.6 3 p.p.m. dye plus 0.1% TPP plus 0.013% QUAT 15. 2 2 p.p.m. dye plus 0.1% TPP plus 0.013% QUAT- 11. 6 2 p.p.m. dye plus 0.2% 'IPP plus 0.013% QUAT 14. 7 2 p.p.m. dye plus 0.3% TP? plus 0.013% QUAT 15. 9 2 p.p.m. dye plus 0.1% 'IPP plus 0.0013% QUAT 4. 0 2 p.p.m. dye plus 0.1% TPP plus 0.0065% QUAT 4. 5 2 p.p.m. dye plus 0.1% TP? plus 0.013% QUA'I 11. 6 2 p.p.m. dye plus 0.1% TPP plus 0.026% QUAT 22. 0

The following observations may be drawn from the data set forth in Table V above. Examples 34-36 show that the amount of fluorescence increases as the amount of anionic fluorescent dye increases. Examples 3739 reveal that the amount of fluorescence increases as the amount of electrolyte increases. Examples 40-43 indicate that the amount of fluorescence increases as the amount of cationic nitrogenous compound increases.

There are set forth in Table VI below data showing the effect of the compositions of the invention upon a variety of hydrophilic and hydrophobic fibers. The composition used was that given in Example 31 above following the dyeing test procedure set forth above.

TAB LE VI Fabric F value Example number:

Spun Arnel 2. 3 W001 3. 9 5. 0

The data given in Table VI above demonstrate that the 2. The composition as defined by claim 1 which further contains from 0% to about 15% by weight of an anionic dispersant having a dissociation constant lower than that of the complex.

3. A fluorescent dye composition especially adapted for imparting increased fluorescence or optical brightness to hydrophilic and hydrophobic fibers consisting essentially of from about 0.25 p.p.m. to about 10 p.p.m. of an anionic fluorescent dye, from about 0.005% to about 0.05% by weight of a fabric softening cationic nitrogenous compound capable of forming a complex therewith, from about 0.02% to about 0.5% by weight of a dissociable salt capable of having a salting out effect upon the complex, and the substantial balance of 100% by Weight of water.

4. The composition as defined by claim 3 wherein the amount of anionic fluorescent dye is about 2 p.p.m., the amount of cationic nitrogenous compound is about 0.013% by weight, and the amount of dissociable salt is about 0.1% by weight.

5. The composition as defined by claim 3 which further contains from 0% to an amount equimolar with the cationic nitrogenous compound of an anionic dispersant having a dissociation constant lower than that 7 5 of the complex.

6. The composition as defined by claim 5 wherein the amount of anionic dispersant is about 0.013% by weight.

7. A process for the preparation of the fluorescent dye composition as defined by claim 5 which comprises blending the components together in an aqueous medium in the following order of addition: cationic nitrogenous compound, anionic fluorescent dye, dissociable salt, anionic dispersant and Water.

16 References Cited UNITED STATES PATENTS 3,309,363 3/1967 Buell 260240 3,356,524 12/1967 Buell 117 33.5

DELBERT E. GANTZ, Primary Examiner A. P. DEMERS, Assistant Examiner US. Cl. X.R. 117-335; 252301.3