BS EN ISO 105-Z04:1998 pdf free download.Textiles Tests for colour fastness Part Z04: Dispersiblity of disperse dyes (ISO 105-Z04:1995).
This part of ISO 105 describes a method for determining the dispersibility. as evaluated by filtering time and filter residue, of disperse dyes.
This test method is used for determining the degree of dispersion under specified conditions in aqueous media only.
NOTE 1 The results of this test method can vary widely unless all tests arc run under exactly the conditions outlined, Any variation in the conditions can cause a test to 1w invalid. Results have been shown to be reproducible in several laboratories when the specified conditions are met.
NOTE 2 Variations in results can be caused by differences in the diameter of the filter funnel, due to the differences in surface area which result, and to variations in the sise and density of the holes in the filter funnel.
2 Normative reference
The following standard contains provisions which. through reference in this text, constitute provisions of this part of ISO 105. At the time of publication, the edition indicated was valid. All standards are subject to revision and parties to agreements based on this part of ISO 105 are encouraged to investigate the possibility of applying the most recent edition of the standard indicated below. Members of IEC and ISO maintain registers of currently valid International Standards.
ISO 3696:1987, Water for a,ialytical laboratory use.
3 Definition
For the purposes of this part of ISO 105, the following definition applies.
3.1
dispersibility
degree to which particles can be broken down to some minimum size such that they will pass through the interstices of a reference filter paper
4 Principle
A quantity of disperse dye is predispersed, heated and passed through filter papers of specified pore size. Using the time of passage and retention of dye on the filter paper, the dispersibility of the dye is then evaluated.
Three variants of the test, depending on the intended dye application, are outlined.
5 Safety precautions
5.1 It is the user’s responsibility to use safe and proper techniques in handling materials in this test method. Consult manufacturers for specific details such as material safety data sheets and other recommendations.
5.2 Good laboratory practice should be followed. Wear safety glasses in all laboratory areas and a single-use dust respirator while handling powder dyes.
5.3 Users should comply with any national and local safety regulations.
6 Apparatus and materials
During the test, use only reagents of recognized analytical grade and only grade 3 water as defined in ISO 3696.
6.1 Nutsch filter (Büch ner funnel), of glass, stainless steel or porcelain, with inner diameter 110 mm, 192 holes and with a total surface area of holes (evenly distributed) of not less than 200 mm2.
6.2 Filter papers1 , of diameter 110 mm, as follows.
— Type A: Having a pore size to retain particles
above 8 pm in diameter;
— Type B: Having a pore size to retain particles
above 25 pm in diameter.
Other papers may be used if quality and microretention characteristics are exactly the same.
6.3 Stainless steel ring, with approximate dimensions 103 mm i.d.. 111 mm o.d. and 8 mm thickness, to hold filter paper of 110 mm diameter in place.
6.4 Filter flask. with side tube, of capacity 1 000 ml.
6.5 Piston or membrane pump, of sufficiently high suction capacity to create a full vacuum of at least 50 kPa under pressure.
6.6 Apparatus to adjust and maintain the vacuum, including vacuum rubber tubing, preferably coupled with a manometer.
6.7 Stopwatch..
6.8 Beakers, of capacity 400 ml or larger.
6.9 Balance, analytical.
6.10 Tel rasodiuni pyrop hosp hate
(TSPP), 10 % (m/V)(100 gil) aqueous solution
prepared with grade 3 water complying with
ISO 3696.
6.11 Acetic acid. 10 % (V/V) (mass fraction 10%)
aqueous solution prepared with grade 3 water
complying with ISO 3696.
Add the weighed dye slowly to 200 ml of vigorously agitated water (6.13) at 45 °C ± 2 °C in a 400 ml beaker (6.8). Use a magnetic stirrer (6.14). Adjust the pH with the pH-meter (6.16) as follows:
— for Tests I and II: pH 4,5 to pH 5,0 using acetic
acid (6.11):
— for ‘rest III: pH 9,0 to pH 10,0 using
TSPP (6.10).
Heat to 70 °C ± 2 °C and hold at this temperature for 5 mm ± I mm. Stir with the magnetic stirrer to prevent localized heating.
NOTE 3 Excessive time lags and holding temperatures may affect the outcome of the test.
Optionally, disperse and stir the dye at 25 °C ±2 °C. In this case, no preheating of the Büchner funnel (see 7.3)is necessary. If this option is used, it shall be stated in the test report.
7.3 Filtration of dispersion
Heat 100 ml to 300 ml of water to 70°C and pour into the Büchner funnel (6.1) without any filter paper in place, to preheat the funnel.
Wait 25s± lOs. Turn the vacuum on (6.4 to 6.6) and keep on until the water has passed through the funnel. Turn the vacuum off, immediately dry the funnel and then place the correct filter papers (6.2) in the funnel (see Table 1).
Two filter papers are used to give a more uniform vacuum across the filtering surface. The filter paper is used as received in the box, with the smooth side up to avoid variations due to texture differences on the rough side. If different types of filter paper are used, the coarser paper shall be underneath. Insert the stainless steel ring (6.3) in the funnel on top of the filter papers, and turn on the vacuum. Adjust the vacuum to 3 kPa to 4 kPa, which is equivalent to a :300 mm to 400 mm water column under pressure.
NOTE 4 Since filter paper is cellulosic in nature, it swells readily when wet. Therefore, if the paper is prewetted to hold it in place in the funnel, the filtration time will be increased, this increase depending on the temperature of the wet filter paper and the time which has been allowed to elapse since wetting. Thus it is imperative that the filter paper is not wet prior to the test, since the microretention characteristics of the paper will be reduced. This is the reason for using the stainless steel ring. which holds the filter paper in place. making prewettng unnecessary. With dyes which have a very small particle size, the speed of filtration of the dispersion will not be changed to any great extent by changing the vacuum. However, with dyes of larger particle size, reducing the vacuum can result in shorter filtration times, even though the suction is not as great. This is because, with an increased vacuum, dyes of larger particle size will block the filter paper, slowing the filtration rate and thus swelling the paper more. This results in longer filtration times and more dye being retained on the filter psper.