1、 ISO 2015 Woven polypropylene sacks for bulk packaging of foodstuffs Sacs tisss en polypropylne pour lemballage en vrac de denres alimentaires INTERNATIONAL STANDARD ISO 23560 Second edition 2015-03-15 Reference number ISO 23560:2015(E) ISO 23560:2015(E)ii ISO 2015 All rights reserved COPYRIGHT PROT
2、ECTED DOCUMENT ISO 2015 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Per
3、mission can be requested from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ISO 23560:2015(E)For
4、eword iv Introduction v 1 Scope . 1 2 Normative references 1 3 T erms and definitions . 1 4 Manufacture 1 4.1 Raw materials 1 4.2 Fabric . 2 5 Sack. 2 6 Liner 3 7 Requirements 3 7.1 Conditioning and test conditions 3 7.2 Construction parameters . 3 7.3 UV resistance 3 7.4 Mass of the bale 3 7.5 Drop
5、 testing . 3 8 Food compatibility 3 9 Marking and packaging . 3 9.1 Marking on sacks . 3 9.2 Packaging . 4 9.3 Marking on bales . 4 10 Sampling and criteria for conformity . 4 10.1 Sampling . 4 10.2 Criteria for conformity . 4 Annex A (normative) Method of calculation of the mass of a sack 6 Annex B
6、 (normative) Breaking strength of fabric and bottom seam 7 Annex C (normative) Drop testing 8 Bibliography 9 ISO 2015 All rights reserved iii Contents Page ISO 23560:2015(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO
7、member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, govern
8、mental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. The procedures used to develop this document and those intended for its further maintena
9、nce are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attenti
10、on is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction a
11、nd/or on the ISO list of patent declarations received (see www.iso.org/patents). Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement. For an explanation on the meaning of ISO specific terms and expressions related to conformit
12、y assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information The committee responsible for this document is ISO/TC 61, Plastics, Subcommittee SC 11, Products. This second edition c
13、ancels and replaces the first edition (ISO 23560:2008), which has been technically revised.iv ISO 2015 All rights reserved ISO 23560:2015(E) Introduction With the removal of trade barriers between nations, there is a need for an International Standard for the packaging, transportation, and storage o
14、f foodstuffs such as cereals. Polypropylene (PP) sacks made from woven fabric are an ideal choice for the packaging of foodstuffs. Such sacks are produced from food-grade polypropylene and ensure the mechanical strength needed for storage and transportation. This International Standard describes the
15、 construction of the sacks, their dimensions, and test methods suitable for ensuring the long-term storage and transportation of foodstuffs in the sacks. ISO 2015 All rights reserved v Woven polypropylene sacks for bulk packaging of foodstuffs 1 Scope This International Standard specifies the genera
16、l characteristics, requirements, and methods of test for woven polypropylene (PP) sacks. It is applicable to woven PP sacks, having a capacity of 50 kg or 25 kg, intended for the transport and storage of foodstuffs, such as cereals, sugar, and pulses. 2 Normative references The following documents,
17、in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 291, Plastics Standard atmos
18、pheres for conditioning and testing ISO 3451-1:2008, Plastics Determination of ash Part 1: General methods ISO 4892-3:2013, Plastics Methods of exposure to laboratory light sources Part 3: Fluorescent UV lamps ISO 4915, Textiles Stitch types Classification and terminology ISO 6591-2, Packaging Sacks
19、 Description and method of measurement Part 2: Empty sacks made from thermoplastic flexible film ISO 13934-1, Textiles Tensile properties of fabrics Part 1: Determination of maximum force and elongation at maximum force using the strip method ISO 13935-1, Textiles Seam tensile properties of fabrics
20、and made-up textile articles Part 1: Determination of maximum force to seam rupture using the strip method 3 T erms a nd definiti ons For the purposes of this document, the following terms and definitions apply. 3.1 woven PP sack container made of woven polypropylene (PP) fabric, closed at one end,
21、in certain cases combined with other flexible materials used, for instance, for the liner to provide the properties required for filling, storage, and distribution of the packaged commodity 4 Manufacture 4.1 Raw materials A suitable grade of PP conforming to food contact requirements shall be utiliz
22、ed in the manufacture of the PP tape/fabric used in the sacks. INTERNATIONAL ST ANDARD ISO 23560:2015(E) ISO 2015 All rights reserved 1 ISO 23560:2015(E) 4.2 Fabric The fabric used in the manufacture of woven PP sacks shall be woven as a tube on a circular loom from PP tapes having a width of (2,5 1
23、) mm. The tapes shall be woven sufficiently tight so that the packaged foodstuff does not leak out of the sack. The construction of the weave shall be sufficiently rough to ensure that filled sacks do not slip from a stack of sacks. The required construction parameters of sacks are given in Table 1.
24、 Table 1 Required construction parameters of fabric and sacks Parameter Requirement Test method Type 1 Type 2 Capacity (kg) 50 25 Dimensions (cm) Inside length 100 + 65 + ISO 6591-2 Inside width 57 48 Mass of sack (g) 135 67 See Annex A Average breaking strength of fabric (N) Lengthwise 918 816 See
25、Annex B Widthwise 918 816 Elongation at break of fabric (%) Lengthwise (20 5) (20 5) See Annex B Widthwise (20 5) (20 5) Average breaking strength of bottom seam (N) 377 337 See Annex B Ash content (for UV stabilized fabric) 3 % max 3 % max ISO 3451-1:2008, Method A, at 600 C 25 C NOTE 1 The dimensi
26、ons specified provide the optimum free space of at least 20 % of the length above the surface of the contents. NOTE 2 The masses given for the sacks are based on typical ones for fabric weighing 106 g/m 2for type 1 sacks and 96 g/m 2for type 2 sacks. NOTE 3 The average breaking strength of the fabri
27、c and the average breaking strength of the bottom seam are calculated with respect to a specimen width of 50 mm. Woven PP sacks of the dimensions specified in Table 1 are suitable for the packaging of foodstuffs such as wheat, rice, pulses, millet, and other similar grains. Other sack dimensions are
28、 allowed by agreement between the purchaser and seller. The mass of such sacks shall be calculated by the method given in Annex A. 5 Sack 5.1 The sack can be flat or gusseted. 5.2 The bottom seam shall be stitched with two rows of chain stitches in accordance with ISO 4915. The two rows of stitches
29、shall be separated from each other by at least 4 mm and the outer stitch shall be at least 7 mm from the outer edge of the sack. The stitching shall be done through a single or double fold so that the stitches pass through a minimum of four layers of the fabric, made in such a way that the seam widt
30、h is at least 25 mm. The number of stitches per unit length shall be (14 2) stitches/dm. These requirements shall be verified by visual inspection.2 ISO 2015 All rights reserved ISO 23560:2015(E) 5.3 The material used for stitching shall be polypropylene tape or any other thread suitable for the pur
31、pose. The stitching shall be uniform with no loose thread or knots. These requirements shall be verified by visual inspection. 5.4 The closure of the filled sack shall be designed to prevent leakage of the contents during transport and handling. 6 Liner If required by the buyer, the unlaminated sack
32、s shall be provided with a loose liner made of a suitable polyolefin film conforming to the requirements for food contact. The width of the liner shall be 10 % more than the width of the sack. The bottom seam of the liner shall be at least 25 mm from its bottom edge. The liner shall be free from pin
33、holes, patches, tears, blisters, and other visible defects. 7 Requirements 7.1 Conditioning and test conditions The atmospheres for conditioning and testing shall be as specified in ISO 291. 7.2 Construction parameters The sacks shall conform to the requirements specified in Table 1, within the limi
34、ts specified in 10.2. 7.3 UV resistance Sacks made of UV-stabilized fabric shall retain at least 50 % of their original breaking strength when tested (see Annex B) after exposure to UV radiation and weathering for 144 h in accordance with the procedure given in ISO 4892-3:2013, Table 4, method A, cy
35、cle No. 1. 7.4 Mass of the bale The mass of a bale of sacks (excluding packing material) shall be within 3 % of the mass calculated by multiplying the number of sacks by the mass specified in Table 1 for one sack. 7.5 Drop testing When tested in accordance with Annex C, sacks shall meet the requirem
36、ents specified in that annex. 8 Food compatibility When used for foodstuffs, as will normally be the case, the sacks shall meet the legal requirements for food contact of the country where they are to be used. 9 Marking and packaging 9.1 Marking on sacks The identification mark of the manufacturer,
37、along with any information required by the buyer, shall be printed on the sacks, using ink or another suitable method that will ensure legibility during use. ISO 2015 All rights reserved 3 ISO 23560:2015(E) 9.2 Packaging The sacks shall be packed to form a circular bale, using a layer of woven PP fa
38、bric for wrapping, and suitably secured. Each bale shall contain 500 sacks or a multiple thereof. 9.3 Marking on bales The bales shall be marked with the following information: a) the name of the manufacturer; b) the type of sack and the sack size; c) the gross mass of the bale; d) the net mass of t
39、he bale; e) the month and year of manufacture; f) any other information required by the buyer. 10 Sampling and criteria for conformity 10.1 Sampling 10.1.1 All the sacks of the same construction in a consignment shall be grouped together to constitute a lot. 10.1.2 The conformity of the lot to the r
40、equirements of this International Standard shall be determined on the basis of tests carried out on samples randomly selected from the lot. 10.1.3 The requirements for sampling for the various tests are specified in Table 2. Table 2 Sample size and criteria for conformity Number of sacks in lot Numb
41、er of bales to be sampled Sample size for visual inspection and measurement of dimensions and mass Sample size for measurement of breaking strength and elongation at break of fabric, breaking strength after exposure to UV radiation, break- ing strength of seam, and ash content Up to 12 500 3 13 8 12
42、 501 to 25 000 5 20 8 25 001 to 50 000 8 32 13 50 001 and above 12 50 20 10.2 Criteria for conformity The lot shall be considered as conforming to the requirements of this International Standard if the following conditions are satisfied: a) the number of sacks found defective in the case of visual i
43、nspection and measurement of dimensions shall be no more than 10 % of the sample size specified in Table 2; b) none of the sacks shall have a mass which is more than 3 % below the lower limit specified in Table 1; c) none of the bales of 500 sacks shall have a mass which is more than 3 % below the c
44、alculated mass of the bale;4 ISO 2015 All rights reserved ISO 23560:2015(E) d) the average breaking strength of the fabric in both the lengthwise and width wise directions shall not be less than the values specified in Table 1, and none of the individual values shall be more than 10 % below the valu
45、e specified in Table 1; e) 10 % of the sacks tested can have a bottom seam strength down to 323 N (33 kgf) in the case of 50 kg sacks and 294 N (30 kgf) in the case of 25 kg sacks, provided the average seam strength of all the sacks tested is 377 N (38 kgf) in the case of 50 kg sacks and 337 N (34 k
46、gf) in the case of 25 kg sacks; f) no sack shall exhibit an elongation outside the range specified in Table 1; g) none of the sacks tested after exposure to UV radiation and weathering shall have a breaking strength less than 50 % of the original breaking strength; h) none of the UV stabilized sack
47、sample shall have ash content more than 3 % as given in Table 1. ISO 2015 All rights reserved 5 ISO 23560:2015(E) Annex A (normative) Method of calculation of the mass of a sack A.1 The total mass of a sack is made up of a) the mass of the fabric and b) the mass of the seam stitching tape or thread.
48、 A.2 Calculate the mass of the sack using the relevant formulae given below. a) Mass of tubular fabric (single-fold stitching): m f= (L + 40) 2W A 10 6(A.1) Mass of tubular fabric (double-fold stitching): m f= (L + 65) 2W A 10 6(A.2) b) Mass of stitching tape or thread: m st= L 1 T 10 6(A.3) wherem
49、f is the mass of the fabric, in g;L is the length of the sack, in mm;W is the width of the sack, in mm; A is the mass per unit area of the fabric, in g/m 2 ;m st is the mass of the stitching tape or thread, in g;L 1 is the approximate length of the stitching tape or thread, in mm;T is the linear density of the stitching tape or thread, in tex.6 ISO 2015 All rights reserved ISO 23560:2015(E) Annex B (normative) Breaking strength of fa
