1、ANSI PH4.206 84 0724350 00333L4 3 7 3CJT ANS I/ASC PH4.206-1984 Revision of ANSI PH4.206-1977 f .I American National Standard 1 for photography (chemicals) - 5-nitrobenzimidazole nitrate ( Approved January 24, 1984 Secretariat: National Association of Photographic Manufacturers, Inc I Warning and Sa
2、fety Precautions Some of the chemicals specified in the test proce- dures of this standard are caustic, toxic, or other- wise hazardous. Specific caution, warning, and danger notices are given in the footnotes but, in addition, the normal precautions required during the performance of any chemical p
3、rocedure shall be exercised at all times. It is recommended that anyone using these chemicals obtains from the manufacturers pertinent information about the hazards, handling, and use of these chemicals. Such information is usually furnished by the chemical manufacturer in the form of a manu- factur
4、ers material safety data sheet (OSHA Form 20 or equivalent). Page 1 of 4 pages Introduction (This Introduction is not part c ANSI/ASC PH4.206-1984.) herican Nation; S t andan This standard is one of a series that establishes criteria of purity for chemicals used in processing photographic materials,
5、 Although the ultimate criterion for suitability of a photographic-grade chemical is its successful perfor- mance in an appropriate photographic use test, the shorter, more economical tests described in this stan- dard are generally adequate. This standard is a revision of American National Standard
6、 Specification or Photographic Grade 5-Nitro- benzimidazole Nitrate, ANSI PH4.206-1977. In this latest revision, the section on physical appearance has been replaced with a section on general information, minor changes in precaution notations have been made, the solution appearance test has been mod
7、ified, and the general format has been changed to be in agree- ment with the style outlined in the Directives for the Technical Work of the International Organization for Standardization (ISO). An American National Standard implies a consensus of those substantially concerned with its scope and prov
8、isions. An American National Standard is intended as a guide to aid the manufacturer, the consumer, and the general public. The existence of an American National Stan- dard does not in any respect preclude anyone, whether he has approved the standard or not, from manufacturing, marketing, purchasing
9、, or using products, processes, or procedures not conforming to the standard. American National Standards are subject to periodic review and users are cautioned to obtain the latest editions. The American National Standards Institute does not develop standards and will in no circumstances give an in
10、terpretation of any American National Standard. Moreover, no person shaii have the right or authority to issue an interpretation of an American National Standard in the name of the American National Standards Institute. CAUTION NOTICE: This American National Standatd may be revised or withdrawn at a
11、ny time. The procedures of the American National Standards Institute require that action be taken to reaffirm, revise, or withdraw this standard no later than five years from the date of ap- proval. Purchasers of American National Standards may receive current information on all standards by calling
12、 or writing the American Na- tional Standards Institute. Copyright 01984 by American National Standards Institute, 1430 Broadway, New York, N.Y. 10018 Ff Y, ANSISC584/4 ANSI PHi*20b 84 0724350 0033335 3 Page 2 of 4 pages 1. Scope This standard establishes criteria for the purity of photographic-grad
13、e 5-nitrobenzimidazole nitrate and describes the tests to be used to determine the purity. 2. General Information 2.1 Physical Properties. 5-nitrobenzimidazole nitrate. is a white to cream-colored powder. The chemical for- mula is C7 H6 N4 O5 and the relative molar mass is 226.13. 2.2 Hazardous Prop
14、erties. 5-nitrobenzimidazole nitrate presents low skin and respiratory hazards. 2.3 Handling and Storage Conditions. hitrobenzimid- azole shall not be stored for prolonged periods at tem- peratures above 38C (100F) or exposed to relative humidities greater than 75%. 3. Suminary of Requirements Assay
15、: Appearance of 0.5% Aqueous Solution: Residue after Ignition (600C 1: 25C): Volatile Matter (70C): Identity : NOTE: m/m = mass per mass 4. Reagents and Materials 99.0% (m/m) minimum 1 O i .O% (m/m) maximum To pass test 0.3% (m/m) maximum 0.3% (m/m) maximum To pass either the melt- ing-point test (2
16、04C to 207C) or have es- sentially the same infrared absorption curve as that of the reference spectrum 4.1 Reagents 4.1.1 Reagents shall be handled in conformity with health and safety precautions as shown on containers or as given in other sources of such information. Proper labeling of prepared r
17、eagents includes adequate health and safety precautions. The discharge of reagents shall conform to applicable environmental regulations. 4.1.2 Reagents used in the test procedures shall be certified reagent-grade chemicals and shall meet the specifications given in Reagent Chemicals, published by t
18、he American Chemical Society (ACS) in 198 1, or chemicals of a purity acceptable for the analysis. The acids and ammonia solutions referred to in all instruc- tions shall be of full strength unless dilution is specified. Dilution is specified in terms of normality, N, when standardization is require
19、d. The number of significant figures to which normality is known shall be sufficient to ensure that the reagent does not limit the reliability of the test method. When dilution is indicated as (1 t X), it means that one volume of the reagent or strong solution is added to X volumes of distilled wate
20、r. 4.2 Water. Whenever water is specified in the test pro- cedures, only distilled water or water of at least equal purity shail be used. 4.3 Glassware. All glassware subject to heating shall be of heat-resistant glass; for example, Pyrex or equiva- lent. 5. Tests Tests shail be made on the samples
21、in their “as re- ceived” condition. 10 shall be followed to determine whether the test sample meets the purity requirements listed in Sec- tion 3. In the last several years, there have been great im- provements in instrumentation for various analyses. Where such techniques have the equivalent accura
22、cy and precision, they may be used in place of the tests described in this standard. The test procedures described in Sections 6 through 6. Assay 99.% (m/m) minimum - 101.0% (m/m) maximum as 5-nitrobenzimidazole nitrate Take about 0.8 gram of sample, weigh accurately to the nearest 0.1 mg, and disso
23、lve in 100 mL of warm water (about 50C) in a 250-mL beaker. Add 3 drops of bromthymol blue indicator and titrate with 0.100 rt 0.002 N sodium hydroxide2 (4 g/L) to the appear- ance of a blue-colored solution. Available from American Chemical Society, 1155 Sixteenth Street, NiV, Washington, DC 20036.
24、 DANGER: Corrosive, causes burns. Avoid contact with eyes, skin, and clothing. Wash thoroughly after handling. In case of contact, flush eyes and skin with water. Obtain medical atten- tion immediately. ANSIIASC PH4.206-1984 ANSI PH4-206 B4 S 0724L50 001L3Lb 5 Percent 5-nitrobenzimidazole nitrate O
25、- (mL NaOH) (N, ( 22.6 131 - weight of sample in grams i If 9 where N = normality of sodium hydroxide 7. Appearance of 0.5% Aqueous Solution (To pass test) Dissolve 5-gram portions of the sample in 1000 mL each of warm (about 50C) water and dilute sodium hydroxide2 solution (100 g/L). Both solutions
26、 shall be clear and free from sediment. A slight haze may be disregarded. 8. Residue after Ignition at 600“ C f 25“ C 0.3% (m/m) maximum Weigh 3.0 grams of the sample to the nearest 0.1 mg in a previously weighed platinum crucible. Incinerate carefully and then ignite the residue at 600C k 25C for 1
27、5 minutes, taking care that no particles are swept out of the crucible. Cool in a desiccator and weigh the crucible and contents to the nearest O. 1 mg. 0 Percent residue after ignition = m3 - ml X 100 m2 -m1 where ml = mass, in grams, of the empty crucible m2 = mass, in grams, of the crucible and t
28、est sample m3 = mass, in grams, of the crucible and residue 9. Volatile Matter at 7OoC 0.3% (m/m) maximum Weigh about 3 grams of the sample to the nearest 0.1 mg into a previously weighed low-form, glass-stoppered weighing bottle. Dry at 70C for 5 hours. Cool in a desiccator and weigh to the nearest
29、 0.1 mg. Percent volatile matter at 70C = m2 - m3 X 100 m2 -m1 where ml = mass, in grams, of the weighing bottle m2 = mass, in grams, of the bottle and sample before drying m3 = mass, in grams, of the bottle and sample O after drying Page 3 of 4 pages 10. Identity To pass either the melting-point te
30、st (204C to 207OC) or have essentially the same infrared absorption curve as that of the reference spectrum 10.1 Melting-Point Test. Dissolve about 1 gram of the sample in 50 mL of hot water (about 85C). Cool to room temperature. Add sodium carbonate solution (20 g/L), dropwise, while stirring the s
31、olution, until a large quantity of the free base is precipitated. Filter and wash the precipitate 6 to 8 times with water. Trans- fer a portion of the free base to a watch glass and dry at 105C for 2 hours. Assemble capillary-tube melting-point apparatus using a thermometer that covers the range 150
32、C - 250C. Prepare three capillary tubes and place in them: (1) the base of the sample to be tested, (2) the base prepared from material known to be 5-nitrobenz- imidazole nitrate, and (3) a finely ground mixture of (1) and (2) mixed in the ratio of 1 :1. Identify the tubes, attach them to the thermo
33、meter, and insert them in the melting-point bath. Heat the bath to approximately 180C and thereafter heat at a con- stant rate of 1 degree per minute, stirring constantly. Note the melting point of the contents of each tube as indicated by the first appearance of liquefaction. The melting point of t
34、he mixture shall be no lower than the lower of the two samples. The melting point of the sample should be approximately 204C to 207C. 10.2 Infrared Identity Test. The sample shall have the absorption characteristics of 5-nitrobenzimidazole nitrate. 10.2.1 Apparatus. An infrared spectrophotometer equ
35、ipped for the 2- to 16-micrometer region and acces- sory equipment for using mineral oil mull or pressed anhydrous potassium bromide plates shall be used in this test. ple to a homogeneous fine powder. Prepare a 0.5% mixture of the sample in finely ground anhydrous potassium bromide. Grind thoroughl
36、y (to approxi- mately 200 mesh). Prepare a pressed plate of the mixture to contain 0.8 to 1 gram of material per square inch (6.45 cm2) of die area. Record the in- frared spectrum from 2 to 16 micrometers. Make a qualitative identification by comparison of the sam- ple curve with the anhydrous potas
37、sium bromide plate reference curve in Figure 1. As an alternative procedure, the S-nitrobenzimid- azole nitrate can be ground and dispersed in mineral oil. If this is done, it is necessary to take into account the presence of interfering mineral oil absorption bands. 10.2.2 Procedure. Grind about 1 gram of the sam- ANSIIASC PH4.2b6-1984 ANSI PH4.206 84 0724150 001L317 7 W Page 4 of 4 pages Figure 1 Infrared Spectrum Reference Curve (5-Nitrobenzimidazole Nitrate in Anhydrous Potassium Bromide) ANSIIASC PH4.206-1984 c
