1、INTERNATIONAL STANDARD ISO 422 Second edition 1994-1 O-l 5 Photography - Processing chemicals - Specifications for p-methylaminophenol sulfate Photographie - Produits chimiques de traitement - Spbifications pour Ie sulfa te de p-m m is the mass, in grams, of the test Portion; 8,6l is the conversion
2、factor obtained from the mass of pmethylaminophenol sulfate equiv- alent to 1 mole of ammonium cerate (i.e. 86,l) x the conversion factor for millilitres to litres (i.e. 0,001) x 100 (for percentage). 7.2 Assay - Alkali titration 72.1 Specification Content of HOC,H,NHCH3-1/2H,SO, shall be 97,5 % (m/
3、m) min. 7.22 Reagents 722.1 Acetone, (CH V is the volume, in millilitres, of the sodium hydroxide (7.2.2.2) used to resch the titration endpoint; m is the mass, in grams, of the test Portion; 17,22 is the conversion factor obtained from the mass of pmethylaminophenol sulfate equivalent to 1 mole of
4、sodium hydroxide (i.e. 172,2) x the conversion factor for millilitres to litres (i.e. 0,001) x 100 (for percentage). 7.3 Identity tests 7.3.1 Melting Point of nitroso derivative 7.3.1.1 Specifications The melting Point shall be from 130 “C to 135 “C. A mixed melting Point shall be from 130 “C to 135
5、 “C and shall not be less than either the Sample nitroso derivative or the Standard nitroso derivative. 7.3.1.2 Reagents 7.3.1.2.1 Sulfuric acid, H2S04, p = 1,84 g/l (DANGERx). 7.3.1.2.2 Sodium nitrite Solution, NaNO*, 100 g/l. Dissolve 10 g of sodium nitrite in 100 ml of water. 7.3.1.3 Apparatus 7.
6、3.1.3.1 Capillary-tube melting Point apparatus, complete with thermometer for the range 100 “C to 2OOOC. 7.3.1.4 Procedure 7.3.1.4.1 Preparation of nitroso derivatives Prepare the nitroso derivatives of the test Sample and a Sample known to be pmethylaminophenol sulfate 3 ISO 422: 1994(E) by treatin
7、g each in the following manner. Dissoive about 0,5 g in 10 ml of water and cool with ice to 5 “C to 10 “C. Add 5 drops of sulfuric acid (7.3.1.2.1) () and then add, drop by drop, 2 ml of the sodium nitrite Solution (7.3.1.2.2). Filter the precipita- tes, then wash with water and dry at 70 “C for 1 h
8、 7.3.1.4.2 Melting Point determinations Prepare three capillary tubes containing: a) the derivative of the Sample to be tested; b) the derivative of the Sample known to be methylaminophenol sulfate; c) a finely ground mixture cf a) and b) mixed in equal proportions. Identify the tubes and attach th
9、em to the ther- mometer. Heat the apparatus (7.3.1.3.1) to about 110 “C. Insert the thermometer with the derivatives of the samples attached, and thereafter heat at a constant rate of 1 “C/min. Note the melting Point of each derivative as indicated by the first appearance of liquefaction. 7.3.2 Infr
10、ared spectrum 7.3.2.1 Specification The infrared absorption curve shall be essentially the Same as that of the reference spectrum (figure 1). This optional recommendation is supplementary to the requirements of 7.3.1. 7.3.2.2 Apparatus 7.3.2.2.1 Test sieve, 63 Fm aperture size, con- forming to ISO 5
11、65. 7.3.2.2.2 Infrared spectrometer, equipped for the 2 Fm to 16 Fm region, and accessory equipment for using potassium bromide plates or mineral oil mull. 7.3.2.3 Procedure Grind about 1 g of the Sample to a homogeneous fine powder and prepare a 0,5 % (m/m) mixture of the Sample in finely ground po
12、tassium bromide. Grind together thoroughly to pass through the test sieve (7.3.2.2.1). Pr epare a pressed plate of the mixture containing 0,13 g to 0,16 g of the mixture per Square centimetre. Record the infrared spectrum from 2 Fm to 16 Fm. Compare with the reference spectrum given in figure 1 e 0
13、ISO NOTE 1 As an alternative procedure, the Sample may be ground and dispersed in mineral Oil. lt will then be neces- sary to take into account the absorption bands of the Oil. 7.4 Residue after ignition 7.4.1 Specification Maximum residue after ignition shall be 0,lO % (mlm). 7.4.2 Procedure Determ
14、ine the percentage residue after ignition in accordance with ISO 10349-4. Use a test Portion of about 5,0 g and ignite in a platinum crucible (600 “C t 50 OC, 4 h, 0,000 1 g)5! Retain this residue for the heavy metals and iron content tests in 7.5 and 7.6. 7.5 Heavy metals content 7.5.1 Specificatio
15、n Maximum content of heavy metals shall be 0,002 % (mlm). 7.5.2 Procedure NOTE 2 The Standard for the iron test (7.6) is prepared in the same way as the heavy metals Standard. Determine the percentage of heavy metals in accord- ante with ISO 10349-5. Use a test Portion of the residue after ignition
16、7.4) corresponding to 2 g of the Sample prepared in accordance with ISO 10349-5: 1992, Use 1 4 corda 76 . l 7.6.1 7.1 (i.e. 10 ml of the 25 ml residue Solution). ml of heavy metals Standard prepared in ac- Ice with ISO 10349-5:1992, 8.1.1. ran content Specification Maximum content of iron shall be
17、0,005 % (m/m). 7.6.2 Procedure Determine the percentage of iron in accordance with ISO 10349-5. Use a test. Portion of the residue after ignition (7.4) corresponding to 2 g of the Sample pre- pared in accordance with ISO 10349-5:1992, 7.1 (i.e. 10 ml of the 25 ml residue Solution). Use 10 ml of iron Standard prepared in accordance with ISO 10349-5: 1992, 8.1 .l e 5) The notation System used for the drying process procedure is given in ISO 10349-1. 4
