Classifications

• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/39—Organic or inorganic per-compounds
  • C11D3/3902—Organic or inorganic per-compounds combined with specific additives
  • C11D3/3937—Stabilising agents
  • C11D3/394—Organic compounds
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06L—DRY-CLEANING, WASHING OR BLEACHING FIBRES, FILAMENTS, THREADS, YARNS, FABRICS, FEATHERS OR MADE-UP FIBROUS GOODS; BLEACHING LEATHER OR FURS
  • D06L4/00—Bleaching fibres, filaments, threads, yarns, fabrics, feathers or made-up fibrous goods; Bleaching leather or furs
  • D06L4/10—Bleaching fibres, filaments, threads, yarns, fabrics, feathers or made-up fibrous goods; Bleaching leather or furs using agents which develop oxygen
  • D06L4/12—Bleaching fibres, filaments, threads, yarns, fabrics, feathers or made-up fibrous goods; Bleaching leather or furs using agents which develop oxygen combined with specific additives

Definitions

• the present invention relates to an improved process for bleaching textile materials. Specifically, this invention is concerned with bleaching materials with an aqueous alkaline solution which contains a peroxy compound and an alkali metal silicate and further containing a novel synergistic combination which functions as a stabilizing agent for the reduction of the decomposition of the peroxy compound and prevention of silicate deposition.
• Preparing textile materials for bleaching, dyeing and finishing generally involves a series of well known steps.
• the material is first singed to burn off excess fibers, desized to remove any artificial coating put on the material for processing, rinsed, and then it is scoured. After scouring, the material is again rinsed and then, in succession, it is bleached, soured, rinsed, mercerized, rinsed, dyed or printed, and finished.
• the bleaching (oxidative) process is desirable in order to attempt to remove impurities or foreign matter and thus ultimately prepare a whiteness in color product suitable for subsequent dyeing and effecting a uniformity of color thereon.
• commercial bleaching (including boiling) processes involve contacting the textile material with alkaline aqueous solution (bath) containing a peroxy compound such as hydrogen peroxide and an alkali metal silicate such as sodium silicate.
• a stabilizing agent to minimize the decomposition of the peroxy compound is well established in the peroxy bleaching art, because, among other things, the oxygen released by decomposition of the peroxy compound in general has no bleaching action as contrasted with the normal autodecomposition of the peroxy compound which does function as a bleaching agent. In fact, the decomposition of the peroxy compound may be harmful. For example, cellulosic materials in strongly alkaline peroxy (bleaching) solutions are attacked by the oxygen from decomposition with the result of loss of strength by the materials. In general, stabilizing agents are of various and diverse nature and the ability of a material to be an effective stabilizing agent is apparently unpredictable.
• the stabilizing agents for peroxy solutions vary in their ability with changes in the prevailing conditions such as pH, temperature conditions and the like of the peroxy solutions.
• the stabilizing agent should preferably 'be effective in alkaline solutions and under relatively high temperature conditions which are frequently encountered in practice as well as being compatible with other additives usually present in the peroxy bleaching solutions such as optical whiteners, that is, brighteners or fluorescent white dyes, wetting agents and the like.
• an object of this invention is to provide an improved method for stabilizing aqueous peroxy solutions.
• Another object of this invention is to'provide a stabilizing agent which affects synergism in the reduction of the decomposition of the peroxy compound and also prevents water-insoluble silicate deposition.
• Another object of this invention is to provide an improved method for bleaching cellulosic materials using aqueous peroxy solutions having dissolved therein novel stabilizing agents.
• synergistic stabilizing agent which is a combination of:
• NTA nitrilotriacetic acid
• CH COOH CH COOH
• the water-soluble salts are also included within the scope of the present invention.
• the preferred salts are the sodium salts.
• Other alkali metal salts such as potassium, lithium and the like, as well as mixtures of the alkali metal salts may be used.
• any water-soluble salt, such as the ammonium salt, which exhibit the characteristics of the alkali metal salt may be also used to practice the invention.
• the magnesium and calcium salts include, without limitation, magnesium acetate, magnesium benzoate, magnesium bromate, magnesium bromide, magnesium chlorate, magnesium chloride, magnesium chromate, magnesium citrate, magnesium fluosilicate, magnesium formate, magnesium lactate, magnesium nitrate, magnesium nitrite, magnesium hypophosphate, magnesium selenate, magnesium sulfate, magnesium sult'ite, magnesium thiosulfate, calcium butyrate, calcium chlorate, calcium chloride, calcium hypochlorite, calcium chromate, calcium formate, calcium glueonate, calcium lactate, calcium maleate, calcium nitrate, calcium nitrite, calcium propionate, calcium l-quinate, calcium sulfide, calcium di-thionate, calcium thiosulfate, calcium valerate, and mixtures of these salts.
• the above list is not all inclusive and the magnesium or calcium salt is anyone which is water-soluble and provides magnesium or calcium ions in an aqueous system. It is to be noted
• the magnesium or calcium salt can be supplied to the aqueous peroxy solution in the form of the magnesium or calcium salts of NTA and/or HEDP.
• the novel stabilizing agent can be in the form of (1) a three component combination of NTA, HEDP, and a magnesium or calcium salt (such as magnesium sulfate), or (2) a two component combination of the magnesium or calcium salts of NTA and HEDP.
• the mole ratios of NTAzMg or Ca salt2I-IEDP be in the range of from about 1:121 to about 5:3:1, preferably from about 2:111 to about 2:2:1.
• textile material includes any natural and/or synthetic fibrous base material such as cotton, nylon, viscose rayon, polyester, e.g., Dacron, hemp, linen, jute, and blends thereof such as, for example, cotton-Dacron, cotton-Dacron-viscose rayon, cotton-nylon-viscose rayon, cotton-Dacron-nylon, cotton-nylon, and cottonpolyester (all in various weight ratios).
• any natural and/or synthetic fibrous base material such as cotton, nylon, viscose rayon, polyester, e.g., Dacron, hemp, linen, jute, and blends thereof such as, for example, cotton-Dacron, cotton-Dacron-viscose rayon, cotton-nylon-viscose rayon, cotton-Dacron-nylon, cotton-nylon, and cottonpolyester (all in various weight ratios).
• the specific synthetic organic surfactant can be any of a wide variety of surface active agents. Typical surfactants are described in US. Pat. No. 2,846,398 and U.S. Pat. No. 3,159,581, both of which are incorporated herein by reference. Furthermore, other publications which describe surfactants which can be used in the present invention processes include Schwartz and Perry, Surface Active Agents, Interscience Publishers, New York (1949) and The Journal of American Oil Chemists Society, Vol. 34, No. 4, pages 170-216 (April, 1957), both of which publications are incorporated herein be reference. The amount of surfactant will vary, depending upon various process conditions and any amount can be used as long as no substantial adverse effect is incurred in the bleaching operation.
• Peroxy solutions which are capable of being stabilized in addition to hydrogen peroxide and its addition compounds, such as the peroxide of sodium and the super oxide of potassium, include urea percompounds, perborates, persulfates, and the peracids such as persulfuric acid, peracetic acid, peroxy monophosphoric acid and their water-soluble salt compounds such as sodium, potassium, ammonium and organic amine salts.
• the pH of the aqueous peroxy solution is usually adjusted with any caustic material in order to effect a pH of greater than 7, e.g. inorganic alkali metal basic materials, such as sodium hydroxide, sodium carbonate, sodium silicate, diand tri-sodium phosphates and the like, including mixtures of these as well as the potassium forms of the foregoing materials, to a pH of between about 7.5 and about 12.5.
• inorganic alkali metal basic materials such as sodium hydroxide, sodium carbonate, sodium silicate, diand tri-sodium phosphates and the like, including mixtures of these as well as the potassium forms of the foregoing materials
• the rate of bleaching in most cases is slow to the extent of being uneconomical for bleaching.
• the amounts of caustic used are from about 1 to about 4 percent by weight based on the total weight of the alkaline aqueous (peroxy) solution.
• concentration of peroxy solutions can vary depending upon, inter alia, the type of peroxy-compound, pH, temperature, type of bleaching desired and the like, however, normal concentrations, i.e., from about 0.01 to about 5 percent can be used with concentrations from about 0.2 to about 3 percent being preferred. It is to be understood that the concentration is not a limitation herein and that any concentration can be utilized as long as the desired end result is achieved.
• the stabilizing agents of the present invention may be dissolved in the peroxy solution which is ready for use or may be incorporated in a concentrated peroxy solution, such as a 35 percent solution of hydrogen peroxide, which is usually further diluted to form the peroxy solution for bleaching.
• the stabilizing agent can be incorporated in dry bleach compositions, such as perborate compositions, by admixing therewith, and the resulting composition dissolved in the aqueous system immediately preceding its end use application.
• the stabilizing agent is intended to be used with the peroxy solution at the time of its use for bleaching purposes.
• the concentration of the stabilizing agent of the present invention in the peroxy solution can vary depending upon, inter alia, concentration of the peroxy solution, type of peroxy-compound used, pH, temperature and the like, and usually for normal concentrations of peroxy solutions and with conventional bleaching methods, the stabilizing agent is preferably present in concentrations from about 0.001 to about 5 percent with from about 0.1 to about 1 percent being especially preferred.
• the methods for bleaching using the peroxy solutions containing the stabilizing agents of the present invention vary widely, as for example, from using the peroxy solutions at normal temperatures, i.e., from about 20 C to about 35 C and contacting the textile material by immersion for periods of time of several hours, i.e., from about 12 to about 36 hours, to using the peroxy solutions at temperatures from about C to about C for periods of time from about 30 minutes to about 6-8 hours, as well as continuous bleaching methods which entail the use of the peroxy solutions at normal temperatures, i.e., about 25 C and contacting the textile material by saturation, removing the excess moisture and exposing the textile material to saturated steam at temperatures from about 100 C to about C for periods of time from a few seconds (about 20) to about 1 hour and even longer in some cases.
• US. Pat. Nos. 2,839,353, 2,960,383, and 2,983,568 are illustrative of being representative of continuous peroxy bleaching methods.
• the temperature of the bleaching (peroxy) solution is desirable in the range of from about 72 F to the boiling point of the bleaching solution but temperatures from about l402 1 F are preferred. It is to be understood that higher temperatures, such as 250 to 300 F, can'be used (with the aid of superatmospheric pressure) where one so desires.
• the bleaching solutions shown in Table I are prepared by mixing together 900 milliliters of deionized water, 22 grams of hydrogen peroxide (35 percent aqueous solution), 1 1 grams of sodium silicate, grams of sodium hydroxide (50 percent aqueous solution) and the indicated amount of the stabilizing agent. Ferrous sulfate is added to the resulting solution in an amount to provide 2 parts per million (ppm) of Fe therein.
• Each individual bleaching solution is contained in a suitable Pyrex glass beaker which in turn is in a thermostated bath of the Ahiba laboratory dyeing machine. Each bleaching solution is heated to and maintained at 210 F for a period of 120 minutes. At the intervals so indicated in Table l, milliliters (ml.) aliquots of solution are withdrawn by pipette, quenched in 100 ml. of H 0, acidified with 1 ml. concentrated H 80 and the residual B 0, is titrated with 0.1N KM O The percent available oxygen (remaining in the bleaching solution at that particular time) is calculated as follows:
• Pefient'fivailabl 05 M (mls. KM O (Normality of KM O (0.008) 100 Weight of original H O in solution.
• the fabric whiteness numbers shown in- Table III are determined relative to a standard (MgO filter being equal to 100) which was as close to perfect whiteness as is possible.
• the results of this Example V are set forth in Table Ill. Regarding these whiteness numbers, a difference of LE o'fIsTKEirTITY KIT) IN THE PRESENCE OF SEVERAL HEAVY METALS 2 AND AT PH 11.3
• one (1) unit is considered significant.
• the stabilizing agents of the present invention exhibit an unexpected result and are substantially better than the prior art materials such as Specifically, it can be seen that with no stabilizing agent in the bleaching solution, the fabric had a whiteness number of 66; with ATMP the value was 87 and with DETPA CaCl the value was 85 and 86. But with the novel stabilizing agents of the present invention, the av-' erage value was 92, a significant difference and improvement. The superiority of these novel stabilizing agents is thus seen.
• the test swatches bleached with the solution containing the present invention stabilizing agents are cut into one inch strips and measured for tensile strength according to ASTM Designation D-39-49', Revised 1955 Standard General Methods of Testing Woven Fabrics, A Breaking Strength, 11. Raveled Strip method. No substantial degradation of the fabric occurred as a result of bleaching with the stabilized peroxy solution, i.e., the tensile strengths of the bleached swatches compared very favorably with unbleached swatches which are similarly tested. Consequently, peroxy solutions stabilized with the stabilizing agents of the present invention exhibit the ability to bleach cellulosic materials, such as cotton fabric, without impairing the material.
• a peroxy solution in accordance with this invention need contain only a peroxy-compound, an alkali metal silicate and the novel stabilizing agents, it will be appreciated that the incorporation in the solution of additional ingredients commonly used in peroxy solutions, such as inorganic alkali metal basic materials, wetting agents, optical whiteners (brightening agents and fluorescent dyes) and the like, is contemplated as being within the invention.
• the novel combination of NTA, HEDP and a watersoluble magnesium or calcium salt functions in two different aspects: (1) reduction of the decomposition of the peroxy compound and (2) prevention of the precipitation of water-insoluble silicates.
• a watersoluble magnesium or calcium salt e.g., magnesium sulfate
• the term stabilizer as used herein is intended to encompass both of these aspects.
• the novelty of this unique combination is predicated upon these two aspects (although the exact physical and/or chemical mechanism is not known) and as such constitutes a significant advancement in the art.
• a process for treating textile materials which comprises the steps of singeing, de-sizing, scouring, bleaching with an alkaline aqueous solution of a peroxy compound and an alkali metal silicate, souring, mercerizing, dyeing or printing, and finishing, the improvement which comprises incorporating into the bleaching solution, at least 0.001 percent by weight, based on the total weight of the bleaching solution, of a stabilizing agent consisting of (a) l-hydroxy ethylidene-l,ldiphosphonic acid having the formula and water-soluble salts thereof, (b) nitrilotriacetic acid and water-soluble salts thereof, and (c) a water-soluble salt of magnesium or calcium, the mole ratio of (a) to (b) to (c) being from about 5:1:1 to 5:321 respectively.
• concentration of the stabilizing agent is from about 0.1 to about 1.0 percent by weight.
• the stabilizing agent is a combination of (a) l-hydroxy ethylidene-l,l-diphosphonic acid, (b) a water-soluble magnesium salt, and (c) nitrilotriacetic acid.

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• 1971
  • 1971-06-03 US US00149855A patent/US3795625A/en not_active Expired - Lifetime
  • 1971-06-03 US US00149854A patent/US3766078A/en not_active Expired - Lifetime
  • 1971-06-03 US US00149856A patent/US3740187A/en not_active Expired - Lifetime
• 1972
  • 1972-05-31 IT IT25149/72A patent/IT956067B/it active
  • 1972-06-02 GB GB2594172A patent/GB1354989A/en not_active Expired
  • 1972-06-02 FR FR7219960A patent/FR2140213B1/fr not_active Expired
  • 1972-06-02 DE DE2226784A patent/DE2226784C3/de not_active Expired
  • 1972-06-02 JP JP5439872A patent/JPS5652080B1/ja active Pending
  • 1972-06-02 ES ES403436A patent/ES403436A1/es not_active Expired

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