Topic outline

  • Welcome to the course "Basic principles of textile printing"


  • COURSE: Basic principles of TEXTILE PRINTING

    The unquestionable importance of printing technology stems from the fact that today, both in everyday and professional life, there is almost no subject on which at least something is not printed. Despite the influence of digital machinery in recent years, screen-printing remains the main technology for a number of producers. Screen-printing has become so prevalent today, that everywhere we look, we see an example.  Even the things that are not readily visible to the eye have been screen-printed – like the electronic products - each of them has a printed circuit board (PCB) that supports the wiring and connections. Screen-printing has come a long way of development, and the so-called “manual” printing processes have long been abandoned.  What used to be called “silk screen” printing has been radically transformed into a high-tech industry with state-of-the-art equipment, and automated techniques.  Today, the industry involves semi-automatic and fully automatic machinery with ICT support implemented in all preparation and production phases. Screen-printing allows for production versatility; for high-end colour retention; for indoor and outdoor applications; and for quality results on variety of surfaces surface, including textiles. The advancement in screen-printing technologies has generated production methods that are fully automated (less lab), more cost effective (better bottom-line), and with finished results that deliver customer satisfaction. In terms of printing pastes components, innovative new chemicals and solvents are developing in the contexts of higher quality and yet ecological acceptability and sustainability. 



    This course is part of the MODULE FINISHING, PRINTING and FUNCTIONALIZATION.

    THREE TYPES OF LEARNING MATERIALS

    • Materials for Students;
    • Materials for Staff; 
    • Materials for Trainers (University Teachers/Researchers) 

    TOPICS:


    The importance and implementation of ICT technology will be included in the theme of each topic. If we consider the application of ICT in textile analogue printing the application can mainly be categorized as:

    1. Application of computers in preparatory phases of textile printing.
    2. Applications of computer in process machineries for textile printing.
    3. Applications of computer in process management for textile printing.
    4. Applications of computer in quality testing equipment for printed textile.
    5. Applications of computer in overall process management for textile printing.

    CAD software solutions for textile printing industries are innovative packages, developed to achieve the highest quality in the shortest time. They must be able to integrate into the entire production process. Must be based on modular concept with all modules working “hand to hand“ to assure and simplify connection between designing (CAD) and screen production (engraving / light exposure - CAM).


  • Materials for STUDENTS

    Creative and engineering students will be able to acquire a knowledge base on which they will be able to independently, according to personal preferences, use textile printing as a tool of their professional work.

  • INTRODUCTION with a brief HISTORICAL OVERWIEV

    • This topic will present a brief introduction with the most significant historical milestones in the development of textile printing as an industrial technology. The importance of textile printing in the economic development of Europe in the period from the 14th to the 19th century will also be explained. A brief overview of historically significant styles and designs in the production of printed textiles in Europe will be given, and the connection between textile printing and the development of the independent profession of textile designer will be explained.


    In this Topic, following chapters are included: 

    • Introduction
    • Printing techniques development in Europe
    • Historically important styles and design
    • Current position and future aspects

  • Basic TOOLS, MACHINERY and CAD/CAM in textile printing

    • In this section, the development of industrial printing technology, with both flat and rotary screens, will be presented, at the most important points. The course of mechanization and automation of industrial textile printing and the importance of the entry of information technologies in the field of textile printing will be explained. The importance of CAD/CAM system in industrial textile printing will also be explained, which from the beginning enabled computerization of individual phases of printing, such as computer separation of pattern colours, to the later possibilities of full automation and computer control of complete printing process from preparation phase to the final product. 
    • Also, the importance of ICT technology and its implementation in the development of industrial setting of textile printing, will be presented for each type of industrial printing technology, except for special styles that will be discussed in a separate chapter.


    In this Topic, following chapters are included: 

    • FLAT screen printing
    • ROTARY screen printing
    • Basic TOOLS in txtile printing
    • CAD/CAM introduction to textile printing technology


      • HAND Printing

      Watch the mastery of Kudhinda hand printers!

      Kudhinda Fabrics specialises in hand-block and screen printed textiles, traditionally patterned in the rich colours of Africa. All of the products are produced by highly skilled team in Harare. 



      The BECKFORD Hand SILK Printing
      An example of the use of hand screen printing in the production of unique silk products that are both accessories and art objects.




      • MACHINE Printing
      Automatized FLAT BED screen printing
      The video shows the operation of an automated printing machine with flat screens. The principle of movable endless belt that moves the textile material, while the flat screens are stationary in the carriers with automation of moving up/down.



      Semi-automatic FLAT BED Printing with MAGNETIC SQUEEGEE
      A semi-automatic printing machine involves automation of certain functions of the machine, such as automatization of textiles/screen/squeegee moving and interact, while other features are still mechanically or manually guided (such as printing paste dosing). In this presentation, pay attention to the dynamism of the magnetic squeegee.



      Fully Automated FLAT BED Printing Machine
      In fully automated flat bed printing machine all features are automatized and digitally controlled.



      ROTARY Screen Printing
      A completely continuous printing process was established only with the introduction of rotary printing. In rotary printing, rotary stencils and textile material are run at the same time, with all effects, ie all colors being printed at the same time. The videos show the dynamism of automated rotary printing machines.






  • SCREEN production with technical characteristics

    • Screen production is also undergoing changes in line with new developmental trends in textile printing technology. Demands on quality, but also environmental and economic sustainability require the development of new, more durable materials for flat-screen meshes, in order to withstand a larger number of prints and different designs, thus reducing the amount of mesh waste. 
    • In this topic, the basic design parameters of flatbed and rotary printing screens will be explained. The method of their production, types of materials for making screens will be presented and the marking of their fineness will be defined.
    • Also, the fundamental mecahnisms of hydrodinamic pressure in the paste wedge and printing paste flow will be presented.


    In this Topic, following chapters are included: 

    • Flat screen preparation
    • Fineness of the screen (mesh)
    • Rotary screens preparation
    • The amount of paste printed onto material, flow and print mechanism

    • FLAT SCREEN Production

      The printing screen or mesh must be attached to the frame under a certain tension. The optimal tension of the screen mesh is directly influencing on the later quality of the stencil (pattern developing), which implies a satisfactory sharpness of the pattern contour. In smaller productions, a machine for manual screen streching is used, while in industrial processes and large scale production, tables with pneumatic streching are used. You can see both on videos.


      MANUAL Streching



      PNEUMATIC Streching



      FINENESS of Screen


  • PATTERN and STENCIL Preparation

    In analogue textile printing technology, the general rule is that a multicolor pattern is printed one color at a time. It is necessary to carry out the preparatory phase in which the design of the pattern is defined, then the smallest repeating unit of the design is defined, and the separation of colors meaning separation of the effects is carried out. It is necessary to completely break down the pattern into individual colors, ie effects, and create a separate stencil for each effect.

    This preparatory phase is time consuming and requires high precision.

    The implementation of CAD systems in the preparatory phase of design and separation of effects is one of the most important aspects of IC technology in textile printing. The introduction of computers significantly simplifies and shortens the preparation phase. Color separation is carried out faster and with much greater precision, which ensures better quality of the further printing process and the final result.

    • Precise sample preparation is key to quality reproduction with conventional printing technology. The lesson explains in detail the methodology of sample preparation, from design, definition of the smallest unit of design (repeat unit) to color separation, which is carried out in three different ways, depending on the complexity of the pattern.


      https://learn.corel.com/graphics-tutorials/coreldraw-tutorials/coreldraw-for-screen-printing/

      It is recommended to visit this site where tutorials for applying features of Corel Draw in pattern preparation for screen printing, can be found.


      The video shows a simple example of color separation of a pattern by the method of classical (individual) color separation or effects. In the language of printing, this method is also called "SPOT color separation". This term actually means that the sample is divided into defined colors, and these already defined colors will be used in later printing. The number of these colors is defined by the pattern and can be as much as the configuration of the printing machine allows.

      Contrary to the "SPOT color separation" methodology, the so-called "PROCESS color separation", which refers to the raster separation of colors, ie the breakdown of the sample into parts of the four primary PROCESS colors - CMYK, by mixing which any color palette is achieved. Only four colors are always used in this method, which means that 4 screens, meaning 4 stencils are always prepared for any sample.


      • SPOT Colour Separation



      • PROCESS Colour Separation



      In addition to PROCES Colour Separation, this video is demonstrating the principle of process colour mixing (CMYK) and the and the gradual construction of the image, ie its three-dimensionality and plasticity, ie photo-like structure.


    • The next stage in the process is the transfer of the separated effects to the appropriate screens. Depending on the nature of the design itself and the type of printing paste to be used, it is necessary to choose the appropriate fineness of the screen and attend to the transfer of effects.

      In this lesson, the principle of making a stencil will be explained in the context of manual screen printing, but also from the aspect of industrial production. The methodology of developing flat and rotary screens (stencils), by the process of light exposure and laser engraving will be explained.

      Also the newest "Computer to Screen" technology will be explained. 


      • Watch on this video:  The process of pattern development on rotary screen (Laser engraving vs. laser exposure system)



      • Laser flatbed engraving machine (flat screen engraving process)


      • Rotary screen coating and pattern engraving


      • Rotary screen printing

    • For the task, carefully watch a series of videos that provide an overview of the basic stages of textile screen printing, from preparation of the design, making a screen and stencil, to choosing a printing method, preparation of printing paste and the printing itself. The videos show the stock printing methodology, which involves printing the whole design composition on one part of a already sewn piece of clothing (for example a T-shirt) or the separate sewing pattern of a future garment.

      How to Screen Print - An Overview 


      Art Preparation


      Film Output


      Screens and Darkroom


      Screen Preparation


      Screen Exposure


      Screen Printing Press Setup


      Press Registration


      Screen Printing Ink


      Screen Printing Techniques


      Curing Your Prints


      Quality Control/Folding & Boxing


      Cleaning Up


      Business Tools and Outro





  • DYES and PIGMENTS

    Any chemical constitution that has the ability to modulate incident light, meaning selective reflections and absorptions of parts of incident light, and that can give a certain surface color, is called a dye or pigment. Therefore, the question arises as to what the difference is

    In this lesson, the basic difference between dyes and pigments and the way they bind to textiles will be defined. There is also a review of pigments with special properties that achieve effects such as fluorescence, phosphorescence, thermochromism and photochromism.

  • COMPOSITION of the Printing Paste

    Each composition of printing paste is based on three ingredients that are constant, regardless of the printing method to be applied or any other process parameter: thickener (implies the ratio of dry matter and water), dyestuff and auxiliaries.

    The lesson contains detailed information on definition of a thickener, the importance of a thickener in the printing process and the selection of a suitable thickener considering the fiber composition of the fabric being printed, the fixing method and the characteristics of the fabric (hydrophobicity, hydrophilicity, porosity, etc.).

  • Textile printing BASIC PHASES and METHODS of Printing

    The whole process of textile printing can be presented in several key phases. The quality of design reproduction depends on these phases. Due to the influence of a large number of parameters, the printing process is more complex than it seems at first, and when an error occurs, it is time consuming to define which part of the process needs to be re-optimized. It is precisely because of this synergistic action of a number of phases, and within each phase of a certain number of parameters, that textile printing ceases to be only an industrial practice but grows into an industrial art.

    As stated in the introductory sentences of this course, the relationship between the exact knowledge, experience and skills of the operator is expressed in the textile printing.

  • ICT in TEXTILE PRINTING

    A modern textile printing system, although implemented by conventional, analog screen printing techniques with flat and rotary templates, is inconceivable without ICT implemented in all phases of the process.

    In the initial phase of the process in which the design preparation, color separation and preparation for the transfer of design to screens takes place, specialized software for creating and processing images enable digital preparation, processing and storage of data.

    In the process of creating a stencils, through specialized software for managing engraving devices, coaters and drying and polymerization units, each phase of the process can be computer-optimized.

    The managing of printing machines is also computerized, and in the final phase of the control of image and color reproduction, computer systems of color objectification and color appearance simulation are unavoidable.

  • Colour OBJECTIFICATION

    Today's processes of coloured textile production, whether it is dyeing or patterning of textiles by printing, are inconceivable without objective color evaluation systems. Consistent color reproduction is one of the key parameters of the quality of printed textile material. In serial production processes, it is crucial to ensure color reproducibility, and given the contradictory requirements, on the one hand the high quality of reproduction, and on the other hand the quick response and short time production process, it is impossible to meet such requirements without computer support and instrumental systems of color objectification.

    Historically, until the development of IC technologies, there was no complete development and implementation of colour objectification systems based on instrumental measurement and computer data processing in industrial settings. 

    Only with the development of information technologies comes the complete development and full implementation of color objectification system, which today occupies a key place not only in the production process but also in the process of creative product design.

  • FINAL Self ASSESMENT QUIZ

  • Course EVALUATION

    • Please answer the questions and rate the course.


  • Material for TEACHERS/RESEARCHERS

    Teaching in the field of textile printing is based on the synergy of science, technology, professional experience and creativity. Textile printing itself is not a scientific branch, and several different fields of science meet in printing technology.

    Teaching/researching in the field of textile printing is based on the synergy of science, technology, professional experience and creativity. Textile printing itself is not a scientific branch and several different fields of science meet in printing technology: chemistry, physics, rheology, mechanical engineering, textile sciences (textile chemistry, textile clothing sciences, textile mechanical sciences and industrial design of textiles and clothing).

    The scheme shows the connection of different branches of science and technology within the field of textile printing, with an equal role also in design, which must work closely, as an artistic component, with the technical. For each segment, there is computer support through CAD and CAM systems, RIP programs, statistical and analytical software as well as specialized computer support for textile printing.




    Based on this first, general scheme of interdisciplinarity of textile printing, the structure of the necessary knowledge is set, in order to create and implement successful education in the field of textile printing.

    It is important to note that the schemes that follow do not represent a proposal for the structure of the course curriculum that would educate students on textile printing, but show the structure of knowledge needed to set up a successful curriculum and to conduct successful educationFundamental to the implementation of the teaching process in the field of textile printing, at the undergraduate and graduate study levels, requires a deep understanding of the heterogeneity of printing technology and the ability to combine certain knowledge in the areas listed in the following schemes to extract those needed for a particular level of program as well as the interests and orientations of students (technology or design).

    Research work in the field of textiles is carried out in each of these segments, plus in the field of information technology (IT) in the context of digitalization and automation of machines, software support for the preparatory phase of printing, which includes pattern preparation and separation, as well as in color visualization. Namely, in the context of the new era in which more and more digital communication and off-site sales of products are carried out, visualization and simulation are becoming a niche of intensive research work in the field of IT for textile technology in general, including textile printing technology.


    • The following diagram shows the basic areas contained in textile printing:




    • For each of these areas, the following is a diagram of the required knowledge:









    This provides guidelines for educational work, but also for research areas that are currently relevant in the field of textile printing.

    Much of the research and innovations currently happening in the field of printing is in the field of mechanical engineering and IT technologies (machine upgrades, automation, computer support for printing machines with all aspects of automation and process optimization).


  • Materials for PROFESSIONALS

    Being a professional in textile printing requires experiential knowledge based on theoretical. But one thing is important to consider, although there are study programs that educate professional textile printing technologists, a real expert does not become by diploma but by experience gained working in the field of printing technology. Today, professional textile printing technologists have at their disposal a wide range of educational programs and workshops that enable continuous training in the profession.


    • Recommended video materials

    https://www.mrprint.com/equipment/ds-4000-digital-squeegee-hybrid-printing-system