BS ISO 18902:2001 pdf – Imaging materials — Processed photographic films, plates and papers — Filing enclosures and storage containers.
1 Scope This International Standard specifies the principal physical and chemical requirements for filing enclosures, albums, and containers particularly designed for storing processed photographic films, plates and papers. The photographic image may be silver-gelatin type, colour (dye-gelatin), diazo or vesicular. This International Standard applies to storage copies and does not include work copies as defined in informative annex B. The requirements are limited to the characteristics that may affect the enclosed item chemically or physically when it is stored under recommended conditions. (For methods of proper storage, see ISO 1 891 1 , ISO 1 891 8 and ISO 1 8920, see [1 2, 1 4, 1 6] in the bibliography.) 2 Normative references The following normative documents contain provisions, which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 699:1 982, Pulps — Determination ofalkaliresistance ISO 6588:1 981 , Paper, boardandpulps — Determination ofpH ofaqueous extracts ISO 1 071 6:1 994, Paperandboard— Determination ofalkalireserve ISO 1 4523:1 999, Photography — Processed photographic materials — Photographic activity test for enclosure materials ASTM D 1 030-95, StandardTest MethodforFiberAnalysis ofPaperandPaperboard, Appendix X5 1 ) TAPPI T236om-99, Kappa numberofpulp 2) TAPPI T406om-94, Reducible sulfurin paperandpaperboard 2) TAPPI T408om-97, Rosin in paperandpaperboard 2)
4 Materials 4.1 General The enclosure material should be free of acids and peroxides that may be released slowly with time and cause degradation to the image or various components of the photograph. For example, ageing blemishes in processed silver gelatin microfilm may be caused by chemicals such as peroxides evolved from the paper (see [1 , 2] in the bibliography). Likewise, the presence of acid in paper can cause paper degradation. The enclosure itself shall be chemically stable. Otherwise, the decomposition products might be harmful to the photographic material, and dirt or dust might be produced that could scratch, or become embedded in the image surface. Cellulose nitrate, polyvinyl chloride, and glassine sheeting are examples of enclosure materials that are either chemically or physically unstable and shall not be used (see [3, 4] in the bibliography). The surface of the enclosure material is also important. The enclosure shall not abrade the photograph. While a slightly textured or matte surface is recommended for the filing enclosure to minimize ferrotyping (see below), a rough surface can produce abrasion problems. There may be other harmful physical characteristics of the enclosure material that may develop under adverse environmental conditions e.g., elevated relative humidity. These include wrinkling and distortions common to glassine paper or ferrotyping of the image surface, i.e., local or overall glazing that can result from contact under pressure with smooth, glossy, plastic enclosure materials. Finally, enclosures shall be of sound and sturdy construction so that the enclosure functions properly during use, without seams or fabrication components failing or otherwise damaging the photographs during storage. Paper, cardboard, and plastic enclosure materials, slide mounts, inks and adhesives shall meet the requirements of the photographic activity test as described in ISO 1 4523.
4.2.2 Paper cartons and boxes Paperboard and corrugated cartons, boxes, or containers that are not in direct contact with the photographic material shall have a pH between 7,0 and 9,5, as determined by the method specified in ISO 6588. An alkali reserve shall be the molar equivalent to at least 2 % calcium carbonate (CaCO 3 ), as determined by the alkali reserve test described in ISO 1 071 6. This alkali reserve shall be accomplished by the incorporation of an alkaline earth carbonate or equivalent. (Compounds such as magnesium carbonate (MgCO 3 ) and zinc oxide (ZnO), in molar equivalencies, correspond to approximately 1 ,6 % reserve. This has the same effect as 2 % molar equivalencies of CaCO 3 ). The alkali reserve shall be evenly distributed throughout the paper or paperboard. 4.2.3 Paper enclosures in direct contact with black-and-white and colour photographic images Paper that is in direct contact with photographic material shall be made from high alpha-cellulose, bleached sulfite, or bleached kraft pulp with an alpha-cellulose content greater than 87 %, as determined by the method given in ISO 699. The paper shall be free from highly lignified fibres such as groundwood (ASTM D 1 030 Appendix X5, TAPPI T 236om), alum rosin sizing (TAPPI T 408om), particles of metal, and shall contain less than 0,000 8 % reducible sulfur (TAPPI T406om). The pH shall be between 7,0 and 9,5 as determined by the method given in ISO 6588. The alkali reserve shall be the molar equivalent to at least 2 % CaCO 3 , as determined by the alkali reserve test described in ISO 1 071 6. This alkali reserve shall be accomplished by the incorporation of an alkaline earth carbonate or the equivalent, as described below. The alkali reserve shall be evenly distributed throughout the paper or paperboard.