1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-21207-0 SANS 6081:2008Edition 3 SOUTH AFRICAN NATIONAL STANDARD Cleaning efficiency of low-foam laundry detergents Published by Standards
4、South Africa 1 dr lategan road groenkloof private bag x191 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa SANS 6081:2008 Edition 3 Table of changes Change No. Date Scope Foreword This South African standard was approved by Nationa
5、l Committee StanSA SC 5140.01B, Detergents, polishes and other chemicals Detergents, soaps and cleaners, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. This document was published in March 2008. This document supersedes SABS SM 1081:2000
6、 (edition 2). SANS 6081:2008 Edition 3 1 Cleaning efficiency of low-foam laundry detergents 1 Scope This standard specifies a method for the determination of the cleaning efficiency of low-foam laundry detergents. 2 Materials and reagents 2.1 Indelible marking ink. 2.2 Standard soiled cotton swatche
7、s1), as follows: twenty standard soiled cotton swatches of size 65 mm 75 mm, designated C-12, impregnated with pigments, groundnut oil, stabilisers and a low concentration of skimmed milk-powder. 2.3 Standard detergent, of composition as in table 1 but with an added mass fraction of 0,2 % protease e
8、nzyme (such as savinase 6.0 T, type W)2). 2.4 Standard hard water, prepared as follows: Dissolve in separate 1 L volumes of distilled water 3,520 g of chemically pure calcium chloride (CaCl22H2O) and 3,947 g of chemically pure magnesium sulfate (MgSO47H2O). Mix both of the solutions together and dil
9、ute to 20 L with distilled water. (This standard has a hardness of approximately 200 mg/L, expressed as calcium carbonate.) 2.5 Pieces of blotting paper, of size approximately 110 mm 120 mm. 1Standard soiled cotton swatches are manufactured by the Centre for Testing Materials, Holland and are commer
10、cially available from the World Wide Web http:/www.cftbv.nl 2Enzymes are supplied by Novozymes, Denmark and are commercially available from the World Wide Web http:/. This information is given for the convenience of users of this standard and does not constitute endorsement by Standards South Africa
11、 of the product named. Equivalent products may be used if they can be shown to lead to the same results. SANS 6081:2008 Edition 3 2 Table 1 Composition of the standard detergent 1 2 Composition Mass fraction % Linear sodium alkylbenzenesulfonate (mean length of alkane chain C11,5) 8,0 0,02 Ethoxylat
12、ed tallow alcohol (14 EO) 2,9 0,02 Sodium soap (chain length C12 22) 3,5 0,02 Sodium tripolyphosphate . 43,7 0,02 Sodium silicate (SiO2/Na2O = 3,3/1) 7,5 0,02 Magnesium silicate 1,9 0,02 Carboxymethylcellulose (CMC) 1,2 0,02 Ethylenediaminetetraacetic acid (EDTA), tetrasodium salt 0,2 0,02 Sodium su
13、lfate (anhydrous) . 21,0 0,02 Optical brightener of cotton (dimorpholinostilbene type) . 0,2 0,02 Moisture . 9,9 0,02 100,0 3 Apparatus 3.1 Photo-electric reflectance meter fitted with a search unit and so designated that the light strikes the test surface in the normal direction and the reflected l
14、ight is measured at an angle of approximately 45 from normal. The search unit is fitted with a filter that provides a spectral response equivalent to observation by the human eye in average daylight. Standardize the reflectance meter by means of a calibrated white enamel working standard that has a
15、reflectance of 79,7 % of that of magnesium oxide. 3.2 Washing device of a suitable mechanical wash-wheel type, that has individual containers, and that is capable of rotating the containers, at a speed of 40 r/min 2 r/min and of maintaining the temperature of their contents at 40 C 1 C. 3.3 Analytic
16、al balance, with a resolution of 0,001 g or better. 3.4 Laboratory-grade glass beaker, with a capacity of at least 5 L. 3.5 Means of heating, such as a hot plate or water bath. 3.6 Non-corrodible (stainless) steel balls, approximately 6 mm in diameter. 3.7 Measuring cylinder with a capacity of at le
17、ast 1 L. 3.8 Timer. 3.9 Steam-iron of the hand- or power-operated type, that is suitable for pressing and drying cotton fabrics. SANS 6081:2008 Edition 3 3 4 Sampling Take a laboratory sample as specified in the relevant product standard. Where no standard exists, take the laboratory sample as agree
18、d upon between the test laboratory and the manufacturer to ensure a reasonable and acceptable reliability at a reasonable and acceptable confidence level. 5 Procedure 5.1 With indelible marking ink (see 2.1), uniquely identify each standard soiled cotton swatch (see 2.2). NOTE It is preferable to fi
19、nish the raw edges of the swatches with stitching to prevent unravelling during testing. 5.2 Using the photo-electric reflectance meter (see 3.1), take three reflectance readings on each side of each standard soiled cotton swatch in turn. Take the readings with the swatch under test superimposed on
20、three unwashed swatches placed on a black enamel standard. Calculate both the mean reflectance of each swatch from the relevant 6 readings and the standard deviation () of the 20 swatches. If the standard deviation does not exceed 2,0, proceed as in 5.4. 5.3 If, however, the standard deviation excee
21、ds 2,0, remove and discard the swatches which have the highest or lowest (or both, as appropriate) reflectance readings and replace with new swatches. Determine, as in 5.2, the mean reflectance of each replacement and calculate the new standard deviation. Repeat this procedure until the standard dev
22、iation of the 20 swatches does not exceed 2,0. 5.4 Start the washing device (see 3.2) and set it to a wash temperature of 40 C 1 C. 5.5 Weigh out (see 3.3) 6,00 g of the standard detergent (see 2.3) into a 5 L beaker (see 3.4) and add 3 L of the standard hard water (see 2.4). 5.6 Weigh out 6,00 g of
23、 the test specimen detergent into a 5 L beaker and add 3 L of the standard hard water. It is recommended that the solutions be prepared sufficiently early to allow the standard and test specimen to be completely dissolved when the test is started. 5.7 Place both of the solutions on a warm hotplate o
24、r in a water bath (see 3.5) 1 h before use and, stirring occasionally, bring their temperatures to 40 C 1 C, and then maintain them at this temperature until the test is started. 5.8 Place 10 balls (see 3.6) in each of the containers of the washing device. 5.9 Mix the standard solution thoroughly an
25、d immediately thereafter, using a measuring cylinder (see 3.7), transfer 200 mL of the solution to a container of the washing device. Mix the remaining solution thoroughly and in the same way transfer 200 mL of the solution into another container of the washing device. Repeat this operation until th
26、ere are 10 containers, each containing 200 mL of standard detergent solution. 5.10 Repeat the procedure given in 5.9 but use the test specimen solution. 5.11 Bring the temperature of the solutions in the containers back to 40 C 1 C, and then add a swatch to each container of both the standard soluti
27、on and the test specimen solution. Close the containers, install them in the washing device, and wash for exactly 30 min (see 3.8), at a speed of 40 r/min 2 r/min. SANS 6081:2008 Edition 3 4 5.12 After washing, remove the swatches from the wash solutions and without squeezing, blot each swatch separ
28、ately between pieces of the dry blotting paper (see 2.5); then rinse, for 1 min, all the swatches together in approximately 4 L of the standard hard water at a temperature of 25 C 3 C, stirring with a glass rod during the rinsing. Remove the swatches from the water and, without squeezing, blot each
29、swatch separately between pieces of the dry blotting paper. 5.13 Steam-iron (see 3.9) the blotted swatches and condition them at ambient temperature for at least 1 h. 5.14 Determine the mean reflectance of each of the washed swatches as in 5.2 but, instead of three unwashed swatches, place three was
30、hed swatches on the black enamel standard. It is recommended that swatches washed in the standard solution be superimposed on three swatches washed in the standard solution; and swatches washed in the test specimen solution be superimposed on three swatches washed in the test specimen solution. 6 Ca
31、lculations 6.1 Calculate the comparative cleaning efficacy CE, expressed as a percentage soil removal, of the test specimen as follows: CE = 1001312RRRRwhere R1is the mean reflectance of the standard soiled cotton swatches before washing (see 5.2 or 5.3, as relevant); R2is the mean reflectance of th
32、e standard soiled cotton swatches after washing with the test specimen; R3is the mean reflectance of the standard soiled cotton swatches after washing with the standard detergent. NOTE The reflectance reading indicates the amount of soil in the swatches. The increase in the reflectance units after w
33、ashing indicates the amount of soil removed. SANS 6081:2008 Edition 3 5 6.2 Use the following formula to determine the standard deviation, 1n, of the difference in the reflectance units between the washed and unwashed swatches for the standard detergent and for the test specimen: ()12=nddn 1 where d
34、 is the individual (R2 R1) difference or individual (R3 R1) difference (see 6.1); d is the mean of the (R2 R1) difference or the mean of the (R3 R1) difference (see 6.1); n is the number of readings. NOTE When determining the standard deviation, take into account the sign (+ or -) of each individual
35、 difference value (d) and the sign of the mean difference value ( d ). 6.3 Use a standard deviation of 2,0 from the mean (see 6. 2) for acceptance of results to be used in the calculation of CE (see 6. 1). 6.4 If 3 out of 10 results are outside the acceptance limit, repeat the test. 7 Test report Re
36、port the following information: a) all the data needed to identify the laboratory sample tested; b) confirmation that the test was carried out in accordance with this standard; c) any deviation from this standard; and d) the comparative cleaning efficiency, expressed as a percentage soil removal, of the detergent under test. Standards South Africa
