USRE15182E - Walteb m - Google Patents

Description

"UNITED STATES PATENT OFF/ICE,

WALTER M. RALPH, OF BUFFALO, NEW

CHEMICAL ('10., INQ, OF NEW YORK,

YORK, ASSIGNOR TO NATIONAL ANILINE.&' N. Y., A CORPORATION OF NEW YORK.

ton, wool, silk, and other m sazo DYE.

No Drawing. Original No. 1,371,979,

To all whom it may concern e it known that I, WALTER M. RALPH, a citizen of the United States, residing at Buffalo, in the county of Erie, State of New York, have invented certain new and useful Improvements in Disazo Dyes; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to a new disazo dye which is of value for dyeing cotfibers, and which can be develo ed on the fiber. The invention includes t e dyed fabrics or other mate rials, dyed with the new dyestufl, as well as the new dyestufl itself.

The new dyestufl' can be obtained by diazotizing nitro Cleves acid, coupling the diazo compound so obtained with m-aminop-cresol methyl ether, diazotizing the monazo compound thus produced and coupling the same in alkaline solution with gamma acid (2.8.6 aminona hthol sulfonic acid), and finally reducing t e nitro group, e. with sodium disulfid.

he followin specific example will further illustrate the invention, the parts being by weight:

29 parts of the sodium salt of Lamina-4- nitro-naphthalene-6 (or -7) monosulfohic acid, or a mixture thereof, hereinafter referred to as ni roCleves acid, in aqueous solution, are treated with 6.9 parts of sodium nitrite and the mixture is run gradually into a mixture of ice and water containing 29 parts of hydrochloric acid (20 B.). By proceeding in this manner, a smooth and rapid diazotization of the nitro Cleves acid is effected. To the resulting cold diazo solution there is added gradually a cold solution of 13.7 parts of m-amino-p-cresol methyl ether in 350 parts of water and 12 parts of hydrochloric acid (20 B.). Coupling begins immediately and is complete in the course of about 2 hours. The solution can. be tested in the usual way for an excess of either the diazo compound or the mamino-p-cresol methyl ether with alkaline R-salt solution or diazotized p-nitranihn solution. \Vhen the coupling is complete the monoazo dye, which has separated as a brownish red product, isfiIteredOfi,

Specification of Reissued Letters Patent. Reissued Aug. 23, 1921- dated March 15, 1921, Serial No. 376,277,1i1ed April 24, 1920. Application for reissue filed June 29, 1921.

Serial No. 481,414.

The monoazo dye is'then stirred up with 500 parts of water anddissolved by the additlon of sodium hydroxid sufiicient to effect solution. To this solution is then added 6.9

parts sodium nitrite and diazotization is'effected by water containing 29 parts of hydrochloric acid (20 B.). Diazotization takes place immediately with a partial separation of the diazocompound. The solution or suspen-- sion ofthe diazo compound thus produced is then addedgradually to a cold solution ofrunning the mixture into ice and.

23.9 parts of gamma acid (2.8.6-am'ino naphthol sulfonic acid) in water containing enough soda ash to dissolve the gamma aci (about 11 parts) and 25 to 35 parts of soda ash in excess. Duringthe addition of the diazo compound the solution is tested to insure an excess of gamma acid, and an alkaline solution is maintained up to the end of the addition. After all the diazo'compound has been'added, stirring is continued for about 1 hour to allow completion of the coupling, after which the solution is heated to about 80 C. and the dyestufi' the form of its sodium salt by of common salt is then filtered ofl'.

The filtered dye thus obtained is then admixed with about 1000 parts of hot water and reduced at a temperature of about C. by the gradual addition of a solution of sodium disulfid., The reduction is easily followed since the unreduced dye is of a purplish color which turns reddish on. the addition of acid, whereas the reduced product is a greenish blue which turns a bright blue with acids. Addition 0f sodium disulfid is continued until no further development of the blue color is observed. Salt is then added to precipitate the dye in the form of its sodium salt. and the dye is then filtered,

the addition Thenew dye can beused to dye cotton,

separated in I (sodium chlorid), The dye wool, silk, and other fibers, giving blue 'shades,- which may be developed to give fast blue-black or green-black shades by diazotizing and developing. on the fiber or fabric with beta-naphthol, m-phenylenediamin, mtol lenediamm, resorcin, etc. 7

he dyed materials produced either by the actionof the new dyestufi itself, or by denaphthalene-6 (0'1;

veloping the new dyestufi' on the fiber or fabric, as well as the new dyestuif itself, form a part of the present invention.

Iclaim:

"1. The herein 3 described new disazo dye obtainable by dia zotizing l-ammo-e-mtro- "monosul-fonic acid ino-p-cresol methyl coupling with m ether, again 'diazotizing and coupling the diazotized intermediate with 2.8.6 amine.- naphthol sulfomc acid, and reducing the nitro group, said dye, inthe form of its sodium salt being a bluish black powder, so:

luble in water to give a blue solution from which hydrochloric acid produces a blue precipitate, and soluble in concentrated sulfuric acid to give a greenish blue solution, said dye dyeing cotton,'wo0l, silk, and other fibers, bluish shades which can be developed to give fast blue black to green-black shades.

2. The herein described new dyes. obtainable by diazotizing the new disazo dye of claim 1 and developing with "a developing agent.

3. Materials dye of claim 1."

.4. Materials dyed with the new: dis azo dyed with the new disazo dye of claim 1, said dye being developed on the fiber of they material. i In testimony whereof I affix my signature.

WALTER M. RALPH.