-SQA- SCOTTISH QUALIFICATIONS AUTHORITY NATIONAL CERTIFICATE MODULE: UNIT SPECIFICATION GENERAL INFORMATION. -Module Number Session

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1 -SQA- SCOTTISH QUALIFICATIONS AUTHORITY NATIONAL CERTIFICATE MODULE: UNIT SPECIFICATION GENERAL INFORMATION -Module Number Session Superclass- WH -Title- PREPARATION OF TEXTILE MATERIALS FOR DYEING, PRINTING AND FINISHING (x 1 / 2 ) -DESCRIPTION GENERAL COMPETENCE FOR UNIT: Describing and applying the wet and dry processes carried out prior to the colouration of textile materials. S 1. distinguish between the different impurities found in textile materials; 2. explain the preparatory processes for cellulosic fibres; 3. explain the preparatory processes for protein fibres; 4. explain the preparatory processes for man-made fibres; 5. apply selected preparatory processes to textile materials; 6. explain the techniques of water removal from and drying of textile materials. CREDIT VALUE: 0.5 NC Credit ACCESS STATEMENT: Standard Grade Chemistry, Mathematics and English at Grade 3 or equivalent. Prior to entry to the module, candidates should pass a test for colour perception For further information contact: Committee and Administration Unit, Hanover House, 24 Douglas Street, Glasgow G2 7NQ. This specification is distributed free to all approved centres. Additional copies may be purchased from SQA (Sales and Despatch section) at a cost of 1.50 (minimum order 5).

2 NATIONAL CERTIFICATE MODULE: UNIT SPECIFICATION STATEMENT OF STANDARDS UNIT NUMBER: UNIT TITLE: PREPARATION OF TEXTILE MATERIALS FOR DYEING, PRINTING AND FINISHING Acceptable performance in this unit will be the satisfactory achievement of the standards set out in this part of the specification. All sections of the statement of standards are mandatory and cannot be altered without reference to SQA. 1. DISTINGUISH BETWEEN THE DIFFERENT IMPURITIES FOUND IN TEXTILE MATERIALS The identification of the nature of the impurities found in textile substrates is correct. The explanation of the effect of the impurities in textile substrates on colouration is correct. Textile protein - wool; hairs; silk. substrates: cellulosic - cotton; linen; viscose. man-made - acrylic; polyamide (nylon); polyester. Impurities: protein wool - wool grease; suint; dirt; vegetable matter; dung; urine; tar; paint; natural pigmentation; spinning oils; stains. hairs - natural grease; dirt; natural pigmentation; spinning oils. silk - sericin (silk gum); dirt; natural colouring. cellulosic cotton - natural fat and wax; proteins; pectins; ash; motes; dirt; natural pigmentation; sizing preparations; stains; linen - natural fat and wax; ash; pectin; natural pigmentation; direct; stains; viscose - processing agents; dirt. man-made - processing agents. 2

3 Effects: poor colour reproduction; unlevelness of colour; inability to achieve desired shade; inadequate colour fastness. Written evidence of the ability to identify the nature of the impurities found in textile materials and explain their effect upon the colouration process covering all of the above specified ranges. 2. EXPLAIN THE PREPARATORY PROCESSES FOR CELLULOSIC FIBRES (c) (d) The selection of the processing sequence for the preparation of woven cotton fabric for dyeing, printing and/or finishing is correct with respect to specified safety legislation. The explanation of the function of each stage in the processing sequence is correct with respect to the preparation of woven cotton fabric for dyeing, printing and/or finishing. The description of the range of machinery required for the preparation of woven cotton fabric is correct. The explanation of modifications in the preparatory processes for cotton yarn, knitted cotton fabric, linen yarn, linen fabric, viscose rayon fabric and cotton blends is correct. Process: inspection; documentation; stitching; brushing; cropping; singeing; desizing; scouring; mercerisation; bleaching; heat setting. Machinery: batch and continuous. Written evidence of the ability to identify the appropriate processing sequences, to explain the function of each process and describe the machinery required to prepare woven cotton fabrics for dyeing, printing and/or finishing covering the given ranges. 3

4 3. EXPLAIN THE PREPARATORY PROCESSES FOR PROTEIN FIBRES (c) (d) The selection of the processing sequence is correct and in accordance with specified safely legislation for the preparation of loose wool, woollen and worsted yarn, woven and knitted wool fabric for colouration. The explanation of the function of each stage in the processing sequence is correct with respect to the preparation of loose wool, woollen and worsted yarn woven and knitted wool fabric for colouration. The description of the range of machinery for preparing loose wool, woollen and worsted yarn, woven and knitted wool fabric is correct. The explanation of modifications required for preparing hairs and silk for colouration is correct. Processes: scouring; bleaching; milling; shrink-resistance; setting. Machinery: loose stock, yarn and fabric scouring machinery; dyeing machinery for scouring, bleaching and shrink-resistance; milling machinery. Written evidence of the ability to select the appropriate processing sequences, to explain the function of the processes and describe the machinery required to prepare protein fibres for colouration covering the above ranges. 4. EXPLAIN THE PREPARATORY PROCESSES FOR MAN-MADE FIBRES (c) The selection of the processing sequences is correct and in accordance with specified safety legislation for preparation of man-made fibres for colouration. The explanation of the function of each process is correct with respect to the preparation of man-made fibres for colouration. The description of machinery required is correct with respect to the preparation of man-made fibres for colouration. 4

5 Man-made fibres: polyester; polyamide (nylon); acrylic. Process: scouring; setting; Machinery: dyeing machinery used in preparation; setting machinery. Written evidence of the ability to identify the processing sequences necessary for preparing man-made fibres for colouration, explain each process and describe the machinery required covering the above ranges. 5. APPLY SELECTED PREPARATORY PROCESSES TO TEXTILE MATERIALS The performance of oxidation bleaching processes in desized, scoured, woven cotton fabric or scoured cotton yard is correct with respect to safety requirements and recommended procedures. The performance of a scouring process on greasy loose stock wool is correct with respect to safety requirements and recommended procedures. Processes: bleaching cellulosic fibres; scouring protein fibres; surface modification of protein fibres. Process chemicals: oxidative bleaching. Cotton: oxiductive bleaching agents buffers; alkali. Scouring protein fibres: non-ionic detergent, alkali. Equipment: standard laboratory apparatus; spectrophotometer. Practical evidence of the ability to perform three selected preparatory processes on cellulosic and protein textile materials whilst complying with the risk assessment for each specified process covering the above ranges. 5

6 6. EXPLAIN THE TECHNIQUES OF WATER REMOVAL FROM AND DRYING OF TEXTILE MATERIALS (c) The explanation of how water is held by textile materials is correct. The description of mechanical methods of water removal is appropriate for textile materials in all forms. The description of textile thermal drying machinery is appropriate for textile materials in all forms. Water: absorbed moisture: mechanically held water. Mechanical water removal: mangles; suction dryers; centrifuges. Thermal water removal: frequency dryers. conduction, convection, radiation dryers; radio Written evidence of the ability to differentiate between the different types of machinery available for the removal of water from textile materials in their various forms after dyeing, printing or finishing covering the above ranges ASSESSMENT RECORDS In order to achieve this unit, candidates are required to present sufficient evidence that they have met all the performance criteria for each outcome within the range specified. Details of these requirements are given for each outcome. The assessment instruments used should follow the general guidance offered by the SQA assessment model and an integrative approach to assessment is encouraged. (See references at the end of support notes). Accurate records should be made of assessment instruments used showing how evidence is generated for each outcome and giving marking schemes and/or checklists, etc. Records of candidates' achievements should be kept. These records will be available for external verification. SPECIAL NEEDS In certain cases, modified outcomes and range statements can be proposed for certification. See references at end of Support Notes. 6

7 Copyright SQA 1994 Please note that this publication may be reproduced in whole or in part for educational purposes provided that: (i) (ii) no profit is derived from the reproduction; if reproduced in part, the source is acknowledged. 7

8 NATIONAL CERTIFICATE MODULE: UNIT SPECIFICATION SUPPORT NOTES UNIT NUMBER: UNIT TITLE: PREPARATION OF TEXTILE MATERIALS FOR DYEING, PRINTING AND FINISHING SUPPORT NOTES: This part of the unit specification is offered as guidance. None of the sections of the support notes is mandatory. NOTIONAL DESIGN LENGTH: SQA allocates a notional design length to a unit on the basis of time estimated for achievement of the stated standards by a candidate whose starting point is as described in the access statement. The notional design length for this unit is 20 hours. The use of notional design length for programme design and timetabling is advisory only. PURPOSE This module will enable the candidate to extend his or her knowledge of the processes necessary to prepare textile fibres in their various forms for dyeing, printing and finishing. SQA publishes summaries of NC units for easy reference, publicity purposes, centre handbooks, etc. The summary statement for this unit is as follows: The module will enable you to develop an understanding of the sequence of processes, the nature of these processes and the machinery required in relation to the preparation of a range of textile materials for dyeing, printing and finishing. You will also learn how to carry out three selected processes safely through small scale practical exercises. CONTENT/CONTEXT Corresponding to Outcomes 1-6: 1. Identifying the impurities in the main textile fibre groups. Effect on the colouration processes and finishing. 2. Processing sequences; principles and practice of inspection; stitching; brushing/cropping; desizing; scouring; bleaching and mercerization. 3. Processing sequences; principles and practice of scouring; bleaching; setting. 4. Processing sequences; principles and practices of scouring; bleaching; setting. 5. Bleaching of cotton; scouring of raw wool; shrink resisting wool. 8

9 6. Water and fibres; mechanical water removal; thermal water removal (drying). APPROACHES TO GENERATING EVIDENCE It is recommended that this module be taken as part of a programme of colouration and finishing technology modules. The module is constructed in such a way as to allow a systematic progression through the outcomes from the identification of the impurity to be removed, the processing sequences required, their function and machinery. The impurities in textiles materials should be discussed and illustrated using a range of visual material such as fibre, yarn and fabric samples. The impurities in textiles materials should be discussed and illustrated using a range of visual material such as fibre, yarn and fabric samples. The preparation of textile materials for dyeing, printing and finishing can be introduced through lectures, prepare text, candidate-centred learning material, overhead projector slides, slides, video, and supported by industrial visits where appropriate. The practical exercises should be structured to support the delivery of the module and its completion. The worksheets should provide general instructions for the selected process and clearly indicate that the candidate requires to carry out procedures accurately and safely, and observe the effects of the selected process on the textile material. ASSESSMENT PROCEDURES Centres may use Instruments of Assessment which are considered by tutors/trainers to be the most appropriate. Examples of instruments which could be used are as follows: Outcome 1 Outcome 2 Outcome 3 Outcomes 4 Outcome 5 It is recommended that an extended response question is used to assess both PCs ensuring that evidence across all of the ranges is given. It is recommended that an extended response question could be carried out to assess the Performance Criteria to (d) ensuring that the range statement and evidence requirements are achieved. A graph may be produced where required. It is recommended that an extended response question be carried out to assess the Performance Criteria to (d) ensuring that the range statement and evidence requirements are achieved. It is recommended that short answer questions be carried out to assess the Performance Criteria to (c) ensuring that the range statement and evidence requirements are achieved. It is recommended that practical exercises be carried out to assess the Performance Criteria and ensuring that the range statement and evidence requirements are achieved. 9

10 Outcome 6 It is recommended that an extended response question is used to assess Performance Criteria to (c). PROGRESSION Candidates could progress onto Higher National units. RECOGNITIONMany SQA NC units are recognised for entry/recruitment purposes. For up-to-date information see the SQA guide 'Recognised and Recommended Groupings'. REFERENCES 1. Guide to unit writing. 2. For a fuller discussion on assessment issues, please refer to SQA's Guide to Assessment. 3. Procedures for special needs statements are set out in SQA's guide 'Students with Special Needs'. 4. Information for centres on SQA's operating procedures is contained in SQA's Guide to Procedures. 5. For details of other SQA publications, please consult SQA's publications list. Copyright SQA 1994 Please note that this publication may be reproduced in whole or in part for educational purposes provided that: (i) (ii) no profit is derived from the reproduction; if reproduced in part, the source is acknowledged. 10