{"id":4356,"date":"2026-07-27T08:04:59","date_gmt":"2026-07-27T08:04:59","guid":{"rendered":"https:\/\/fsxchemical.com\/?p=4356"},"modified":"2026-09-11T06:51:32","modified_gmt":"2026-09-11T06:51:32","slug":"sodium-alginate-for-screen-printing-paste-formulation-application-and-troubleshooting","status":"publish","type":"post","link":"https:\/\/fsxchemical.com\/bn\/blog\/sodium-alginate-for-screen-printing-paste-formulation-application-and-troubleshooting\/","title":{"rendered":"Sodium Alginate for Reactive Screen Printing: Paste Preparation and Troubleshooting"},"content":{"rendered":"<p class=\"wp-block-wd-paragraph wd-ee23f2f9\"><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6069\">For reactive flat- or rotary-screen printing, sodium alginate must provide controlled transfer, clean screen passage, pattern definition, paste stability and practical wash-off. Select the concentration and viscosity by the exact grade, formulation, fabric, screen, machine and test method; one universal paste viscosity or dosage cannot cover every production line.<\/a><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-3ec783c8\"><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6069\">This guide covers the key elements of sodium alginate paste formulation for reactive dye screen printing, how to optimize application for flat and rotary screen processes, and how to diagnose and resolve the most common production problems.<\/a><\/p>\n\n\n\n<div class=\"wp-block-wd-divider wd-style-line wd-5285aba9\"><\/div>\n\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>Selection point<\/th><th>Flat-screen priority<\/th><th>Rotary-screen priority<\/th><\/tr><\/thead><tbody><tr><td>Paste transfer<\/td><td>Controlled penetration during intermittent squeegee strokes<\/td><td>Stable transfer under continuous high-shear operation<\/td><\/tr><tr><td>\u09b0\u09bf\u0993\u09b2\u099c\u09bf<\/td><td>Clean release and edge definition for the selected design<\/td><td>Shear thinning, recovery and circulation stability<\/td><\/tr><tr><td>Filtration and screen passage<\/td><td>No particles or residue that disturb fine areas<\/td><td>Low residue and stable passage during long runs<\/td><\/tr><tr><td>Holding behavior<\/td><td>Repeatability across tables, colors and pauses<\/td><td>Viscosity control through tanks, pumps, pipes and screens<\/td><\/tr><tr><td>Approval test<\/td><td>Print trial on the actual fabric, screen and squeegee settings<\/td><td>Pilot run at intended speed, circulation and production duration<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-e32078b8\">Sodium Alginate Paste Formulation for Reactive Dye Screen Printing<\/h2>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-9c9a777e\">Core Components of a Reactive Dye Printing Paste<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-37aded17\">A standard reactive dye printing paste for screen printing on cotton contains the following core components:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6069\"><strong>\u09b8\u09cb\u09a1\u09bf\u09af\u09bc\u09be\u09ae \u0985\u09cd\u09af\u09be\u09b2\u099c\u09bf\u09a8\u09c7\u099f<\/strong> \u2014 the primary thickener, controlling paste viscosity and rheology<\/a><\/li>\n\n\n\n<li><strong>\u09aa\u09cd\u09b0\u09a4\u09bf\u0995\u09cd\u09b0\u09bf\u09af\u09bc\u09be\u09b6\u09c0\u09b2 \u09b0\u099e\u09cd\u099c\u0995<\/strong> \u2014 dissolved in the paste at the concentration required for the target color depth<\/li>\n\n\n\n<li><strong>\u0995\u09cd\u09b7\u09be\u09b0\u0995<\/strong> \u2014 typically sodium carbonate (soda ash) or sodium bicarbonate, required to raise paste pH for reactive dye fixation during steaming<\/li>\n\n\n\n<li><strong>\u0987\u0989\u09b0\u09bf\u09af\u09bc\u09be<\/strong> \u2014 a hygroscopic agent that retains moisture during steaming to support dye dissolution and fixation<\/li>\n\n\n\n<li><strong>Anti-reducing agent<\/strong> \u2014 such as sodium m-nitrobenzenesulphonate, used to prevent reduction of certain reactive dyes during steaming<\/li>\n\n\n\n<li><strong>\u099c\u09b2<\/strong> \u2014 the solvent medium; water quality (hardness, ionic content) affects paste performance<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-b473f4a6\">The proportions of each component depend on the dye class, target color depth, fabric type, and steaming conditions. There is no single universal formula \u2014 paste recipes are typically developed for specific dye classes and adjusted based on production experience.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-b8505050\">Sodium Alginate Concentration and Viscosity Target<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-80536006\"><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6069\">A common starting evaluation for some textile sodium alginate grades is around 3.5\u20134.0% in the stock paste, but this is not a universal finished-paste dosage. The required level changes with grade viscosity, total formulation, preparation method and target printing behavior.<\/a><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-5dba188e\">Do not specify a target viscosity without the concentration, temperature, preparation, hydration time, instrument, spindle, speed and reading time. Flat and rotary screens also impose different shear, transfer and circulation conditions, so compare complete-paste performance rather than relying on a generic mPa\u00b7s range.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-d7a02368\">Prepare and fully hydrate the sodium alginate stock paste before evaluating the complete formulation. After alkali is added, define and test the permitted holding time under the mill\u2019s actual temperature and storage conditions because viscosity and dye stability can change with pH, time and heat.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-5d265a2a\">Alkali Selection and Timing<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-1e07d293\"><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6069\">The choice of alkali affects both paste stability and fixation efficiency. Sodium carbonate (soda ash) at typical concentrations (10\u201320 g\/L) provides a higher pH than sodium bicarbonate and supports faster fixation but also accelerates paste degradation \u2014 particularly at elevated ambient temperatures. Sodium bicarbonate gives a lower pH and slower fixation, which can be advantageous for extended print runs where paste stability is a priority.<\/a><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-28535fc8\">In two-phase printing processes, alkali is applied separately (by padding the fabric before printing, or by post-printing treatment) rather than being included in the print paste. This approach extends paste pot life significantly and is used in some high-volume operations where paste stability across a full shift is important.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-e15685d1\">Regardless of which approach you use, alkali should be added to the paste as close to the time of use as practical, and paste containing alkali should not be stored beyond the shift in which it was prepared.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/fsxchemical.com\/wp-content\/uploads\/2025\/11\/\u7b2c1\u7bc7\u6587\u7ae0A-4-1024x768.webp\" alt=\"\" class=\"wp-image-7959\" style=\"aspect-ratio:1.3333183108747577;width:826px;height:auto\" srcset=\"https:\/\/fsxchemical.com\/wp-content\/uploads\/2025\/11\/\u7b2c1\u7bc7\u6587\u7ae0A-4-1024x768.webp 1024w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2025\/11\/\u7b2c1\u7bc7\u6587\u7ae0A-4-150x113.webp 150w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2025\/11\/\u7b2c1\u7bc7\u6587\u7ae0A-4-1200x900.webp 1200w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2025\/11\/\u7b2c1\u7bc7\u6587\u7ae0A-4-300x225.webp 300w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2025\/11\/\u7b2c1\u7bc7\u6587\u7ae0A-4-768x576.webp 768w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2025\/11\/\u7b2c1\u7bc7\u6587\u7ae0A-4.webp 1448w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<div class=\"wp-block-wd-divider wd-style-line wd-32a6ec90\"><\/div>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-75551f89\"><em><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6094\">Flat Screen vs. Rotary Screen Printing: Paste Requirements<\/a><\/em><\/h2>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-fbdf8c0b\">\u09ab\u09cd\u09b2\u09cd\u09af\u09be\u099f \u09b8\u09cd\u0995\u09cd\u09b0\u09bf\u09a8 \u09aa\u09cd\u09b0\u09bf\u09a8\u09cd\u099f\u09bf\u0982<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-11005dd4\"><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6069\">In flat screen printing, paste is applied to the screen and pushed through the mesh onto the stationary fabric by a squeegee moving across the screen. The screen is then lifted and the fabric advances before the next print stroke.<\/a><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-a653864d\">Flat screen printing typically operates at lower speed than rotary screen printing and allows slightly more flexibility in paste viscosity. The paste needs to flow readily under squeegee pressure but should not spread beyond the screen opening boundaries before the screen is lifted. Medium viscosity sodium alginate grades at concentrations toward the lower end of the typical range (3\u20134%) are commonly used.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-4a558b71\">One practical consideration in flat screen printing is paste drying on the screen surface between strokes if the print speed is slow. If this is occurring, check whether paste viscosity is too high (thicker paste dries faster at the surface), whether ambient humidity is very low, or whether the time between strokes is longer than typical.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-1008c65e\">\u09b0\u09cb\u099f\u09be\u09b0\u09bf \u09b8\u09cd\u0995\u09cd\u09b0\u09bf\u09a8 \u09aa\u09cd\u09b0\u09bf\u09a8\u09cd\u099f\u09bf\u0982<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-c5f22cfa\"><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6094\">In rotary screen printing, paste is fed continuously into the inside of a rotating cylindrical screen and pushed through the mesh by an internal squeegee or magnetic bar as the fabric moves beneath. Rotary screen printing operates at much higher speeds than flat screen printing and requires paste that maintains consistent rheology throughout a long production run.<\/a><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-6e8bbca6\">Paste viscosity stability is particularly important in rotary screen printing \u2014 viscosity that drifts during the run causes shade variation across the fabric length. Medium to high viscosity sodium alginate grades at concentrations toward the higher end of the typical range (4\u20136%) are commonly used, and paste is typically prepared in large batches to minimize preparation frequency during a run.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-f11f9407\">Rotary screen paste systems are often enclosed or covered to reduce evaporation and viscosity change due to water loss during the run. If viscosity is increasing during a run without other explanation, check whether evaporation is occurring in the paste feed system.<\/p>\n\n\n\n<div class=\"wp-block-wd-divider wd-style-line wd-9de25065\"><\/div>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-2320842d\">Common Screen Printing Problems and Paste-Related Causes<\/h2>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-71a43224\">Color Bleeding and Pattern Edge Sharpness<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-fa16ebec\">Color bleeding \u2014 where color spreads beyond the intended pattern boundary \u2014 is one of the most common defects in reactive dye screen printing and is frequently related to paste viscosity. Paste that is too fluid does not hold the dye in place after transfer to the fabric; the dye migrates laterally before fixation, creating soft or blurred pattern edges.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-1a0dc88e\">If bleeding is occurring, first check paste viscosity at the time of printing (not just at preparation). If viscosity has dropped during the run, investigate the cause of viscosity loss \u2014 degradation, evaporation, or temperature increase are the most common causes. If viscosity is at the correct level and bleeding is still occurring, consider whether the screen mesh count is appropriate for the pattern fineness, and whether fabric surface preparation is adequate.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-a4387834\">Screen Blockage<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-431ccda4\">Screen blockage \u2014 paste drying in or on the screen mesh and preventing clean transfer \u2014 can result from paste with excessive viscosity, paste that contains undissolved particles, paste that dries too quickly at the mesh surface, or inadequate cleaning between runs.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-eb2de942\">For blockage caused by undissolved particles, check sodium alginate dissolution completeness during paste preparation \u2014 filter a sample of the prepared paste base through a fine mesh and check for retained particles. If particles are present, extend mixing time or check water temperature during dissolution.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-38737cba\">For blockage caused by surface drying, check whether paste viscosity is higher than needed, whether ambient humidity is very low, or whether print speed is slow enough that paste is sitting on the mesh surface for extended periods between strokes.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-3945b16b\">Uneven Color Depth Across the Fabric Width<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-665cd0b6\">Uneven color depth across the fabric width \u2014 often showing as darker edges and lighter center, or vice versa \u2014 typically indicates uneven paste transfer rather than a dye or fixation problem. Common causes include uneven squeegee pressure across the screen width, screen tension variation, or paste viscosity inconsistency within the batch.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-5101542d\"><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6094\">Check paste viscosity by sampling from different positions in the paste trough \u2014 front, middle, and back \u2014 to confirm that viscosity is uniform throughout the batch. If viscosity varies within the trough, the paste was not adequately mixed before use or separation is occurring during the run.<\/a><\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-dfc0976a\">Paste Transfer Inconsistency Between Early and Late Prints<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-8a08985a\"><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6094\">If color depth is consistent within individual prints but differs between early and late prints in a production run, the cause is usually paste viscosity change during the run rather than an application problem. Measure paste viscosity at regular intervals \u2014 at preparation, mid-run, and end-of-run \u2014 to establish whether viscosity is drifting and at what rate.<\/a><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-7f4dd417\">If viscosity is dropping during the run, refer to the viscosity stability guidance and investigate temperature, mechanical shear, and alkali degradation as potential causes. If viscosity is increasing, check for evaporation from the paste system.<\/p>\n\n\n\n<div class=\"wp-block-wd-divider wd-style-line wd-bfb664b2\"><\/div>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-603b88f1\"><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6094\">Post-Printing Process: Drying, Steaming, and Washing-Off<\/a><\/h2>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-6742037f\">Intermediate Drying Before Steaming<\/h3>\n\n\n\n<figure class=\"wp-block-image is-resized\"><img decoding=\"async\" src=\"https:\/\/fsxchemical.com\/wp-content\/uploads\/2026\/08\/fsx-chemical-cmc-textile-rotary-screen-machine.webp\" alt=\"\" class=\"wp-image-10779\" style=\"aspect-ratio:1.5889683091909672;width:1376px;height:auto\"\/><\/figure>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-e4d4ceb3\">After printing, the fabric is typically dried before entering the steamer. Intermediate drying removes surface moisture from the paste film and prevents dye migration during the early part of the steaming process. However, over-drying \u2014 removing too much moisture from the paste film \u2014 reduces the moisture available for dye fixation during steaming and can lower fixation rate.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-b1e336a0\">The appropriate drying conditions depend on the paste formulation (particularly urea content, which retains moisture), the steamer type, and the dye class. Confirm drying temperature and time with reference to your paste formulation and steaming system. If fixation rate is lower than expected and steaming conditions are correct, check whether intermediate drying is removing too much moisture before steaming begins.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-8b7551de\">Steaming for Reactive Dye Fixation<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-0db6911b\">Reactive dye fixation requires steaming in saturated steam \u2014 steam at 100% relative humidity at the steaming temperature. For most reactive dye classes on cotton, steaming at 100\u2013102\u00b0C for 8 to 12 minutes is standard. The sodium alginate paste must retain adequate moisture during steaming to keep the fiber swollen and allow dye molecules to diffuse in and react with hydroxyl groups.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-e2754f8f\">If fixation rate is consistently lower than expected despite correct steaming time and temperature, check steam saturation in the steamer \u2014 unsaturated or superheated steam dries the paste film rather than maintaining moisture, reducing fixation. Also confirm that urea content in the paste is adequate for your steaming conditions.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-809480e5\">Washing-Off After Steaming<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-ef6aca9c\">After fixation, the fabric must be washed to remove unfixed dye, hydrolyzed dye, and residual sodium alginate from the fabric surface. The standard washing-off sequence for reactive dye printing is: cold rinse, hot wash (80\u201395\u00b0C) with soaping agent, second hot wash, cold rinse.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-9ab44985\"><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6069\">Sodium alginate dissolves readily in hot water and is removed efficiently in the hot wash stage without requiring enzymatic or chemical assistance. If residual paste is detected on the fabric after washing \u2014 by tactile assessment, UV inspection, or chemical test \u2014 extend the hot wash time or increase wash temperature rather than adding chemicals.<\/a><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-1aaab310\">Incomplete washing-off leaves unfixed dye on or near the fiber surface, which reduces wash fastness even when fixation rate was adequate. Ensuring thorough washing-off is as important as optimizing the paste formulation and steaming conditions for achieving target fastness grades.<\/p>\n\n\n\n<div class=\"wp-block-wd-divider wd-style-line wd-526c6e6a\"><\/div>\n\n\n\n\n<h2 class=\"wp-block-heading\">\u09aa\u09cd\u09b0\u09be\u09af\u09bc\u09b6\u0987 \u099c\u09bf\u099c\u09cd\u099e\u09be\u09b8\u09bf\u09a4 \u09aa\u09cd\u09b0\u09b6\u09cd\u09a8\u09be\u09ac\u09b2\u09c0<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">What concentration of sodium alginate should be used for screen printing?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A common stock-paste starting evaluation for some grades is around 3.5\u20134.0%, but the correct level depends on grade viscosity, formulation and production target. Confirm it through a defined viscosity method and printing trial.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Can one viscosity target be used for both flat and rotary screens?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Not reliably. Screen construction, squeegee action, circulation, speed, fabric and design change the required rheology. Record the complete test method and validate on the actual machine.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Why can the screen block even when viscosity is correct?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Undissolved particles, insoluble residue, contamination, damaged screens, dried paste or poor filtration can cause blockage. Inspect residue and preparation records instead of changing viscosity alone.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">When should alkali be added to a reactive printing paste?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Follow the approved formulation and addition sequence. Once alkali is present, control temperature and holding time because paste viscosity and dye stability may change.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">What should be compared before approving a bulk grade?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Compare stock and complete-paste viscosity, hydration, filtration, holding stability, transfer, edge definition, color yield after wash-off, handle and first-batch consistency.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For grade comparison, send the current TDS, paste recipe, viscosity method and defect photographs through <a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%b8%e0%a7%87%e0%a6%ac%e0%a6%be\/%e0%a6%ae%e0%a6%bf%e0%a6%b2%e0%a6%bf%e0%a6%a4-%e0%a6%a8%e0%a6%ae%e0%a7%81%e0%a6%a8%e0%a6%be\/\">FSX Chemical Samples &amp; Matching<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-60cf1321\">How FSX Chemical Supports Your Screen Printing Process<\/h2>\n\n\n\n<figure class=\"wp-block-image is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1600\" height=\"1200\" src=\"https:\/\/fsxchemical.com\/wp-content\/uploads\/2026\/07\/fsx-chemical-sodium-alginate-lab-sample-display-1600x1200-1.webp\" alt=\"\u099f\u09c7\u0995\u09cd\u09b8\u099f\u09be\u0987\u09b2 \u09aa\u09cd\u09b0\u09bf\u09a8\u09cd\u099f\u09bf\u0982 \u09a5\u09bf\u0995\u09a8\u09be\u09b0 \u09ae\u09c2\u09b2\u09cd\u09af\u09be\u09af\u09bc\u09a8\u09c7\u09b0 \u099c\u09a8\u09cd\u09af \u09b8\u09cb\u09a1\u09bf\u09af\u09bc\u09be\u09ae \u0985\u09cd\u09af\u09be\u09b2\u099c\u09bf\u09a8\u09c7\u099f \u09aa\u09be\u0989\u09a1\u09be\u09b0 \u0993 \u09a6\u09cd\u09b0\u09ac\u09a3\u09c7\u09b0 \u09a8\u09ae\u09c1\u09a8\u09be\" class=\"wp-image-9734\" style=\"width:1173px;height:auto\" srcset=\"https:\/\/fsxchemical.com\/wp-content\/uploads\/2026\/07\/fsx-chemical-sodium-alginate-lab-sample-display-1600x1200-1.webp 1600w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2026\/07\/fsx-chemical-sodium-alginate-lab-sample-display-1600x1200-1-300x225.webp 300w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2026\/07\/fsx-chemical-sodium-alginate-lab-sample-display-1600x1200-1-1024x768.webp 1024w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2026\/07\/fsx-chemical-sodium-alginate-lab-sample-display-1600x1200-1-768x576.webp 768w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2026\/07\/fsx-chemical-sodium-alginate-lab-sample-display-1600x1200-1-1536x1152.webp 1536w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2026\/07\/fsx-chemical-sodium-alginate-lab-sample-display-1600x1200-1-16x12.webp 16w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2026\/07\/fsx-chemical-sodium-alginate-lab-sample-display-1600x1200-1-1200x900.webp 1200w, https:\/\/fsxchemical.com\/wp-content\/uploads\/2026\/07\/fsx-chemical-sodium-alginate-lab-sample-display-1600x1200-1-150x113.webp 150w\" sizes=\"auto, (max-width: 1600px) 100vw, 1600px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-398eaeb8\"><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%aa%e0%a7%8d%e0%a6%b0%e0%a6%af%e0%a6%bc%e0%a7%8b%e0%a6%97%e0%a6%b8%e0%a6%ae%e0%a7%82%e0%a6%b9\/%e0%a6%b8%e0%a7%8b%e0%a6%a1%e0%a6%bf%e0%a6%af%e0%a6%bc%e0%a6%be%e0%a6%ae-%e0%a6%85%e0%a7%8d%e0%a6%af%e0%a6%be%e0%a6%b2%e0%a6%9c%e0%a6%bf%e0%a6%a8%e0%a7%87%e0%a6%9f%e0%a7%87%e0%a6%b0-%e0%a6%ac%e0%a7%8d\/\" data-type=\"page\" data-id=\"6069\">FSX Chemical supplies sodium alginate grades for reactive dye flat screen and rotary screen printing, across a range of viscosity specifications suited to different fabric types, screen mesh counts, and printing speeds. Technical datasheets, batch certificates of analysis, and sample quantities are available on request.<\/a><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-499d27c9\">If you are developing a new paste formulation, troubleshooting a production problem, or evaluating a grade change, our technical team can assist with paste formulation guidance and grade selection based on your specific process conditions.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-4899f598\"><strong>\u09aa\u09b0\u09ac\u09b0\u09cd\u09a4\u09c0 \u09aa\u09a6\u0995\u09cd\u09b7\u09c7\u09aa:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%86%e0%a6%ae%e0%a6%be%e0%a6%a6%e0%a7%87%e0%a6%b0-%e0%a6%b8%e0%a6%be%e0%a6%a5%e0%a7%87-%e0%a6%af%e0%a7%8b%e0%a6%97%e0%a6%be%e0%a6%af%e0%a7%8b%e0%a6%97-%e0%a6%95%e0%a6%b0%e0%a7%81%e0%a6%a8\/\" data-type=\"page\" data-id=\"20\"><strong>\u099f\u09bf\u09a1\u09bf\u098f\u09b8 \u0985\u09a8\u09c1\u09b0\u09cb\u09a7 \u0995\u09b0\u09c1\u09a8<\/strong> \u2014 review viscosity, DS, and concentration specifications for your target screen printing application<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%86%e0%a6%ae%e0%a6%be%e0%a6%a6%e0%a7%87%e0%a6%b0-%e0%a6%b8%e0%a6%be%e0%a6%a5%e0%a7%87-%e0%a6%af%e0%a7%8b%e0%a6%97%e0%a6%be%e0%a6%af%e0%a7%8b%e0%a6%97-%e0%a6%95%e0%a6%b0%e0%a7%81%e0%a6%a8\/\" data-type=\"page\" data-id=\"20\"><strong>\u09a8\u09ae\u09c1\u09a8\u09be \u0985\u09a8\u09c1\u09b0\u09cb\u09a7 \u0995\u09b0\u09c1\u09a8<\/strong> \u2014 run paste preparation and print trials before committing to bulk volume<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%86%e0%a6%ae%e0%a6%be%e0%a6%a6%e0%a7%87%e0%a6%b0-%e0%a6%b8%e0%a6%be%e0%a6%a5%e0%a7%87-%e0%a6%af%e0%a7%8b%e0%a6%97%e0%a6%be%e0%a6%af%e0%a7%8b%e0%a6%97-%e0%a6%95%e0%a6%b0%e0%a7%81%e0%a6%a8\/\" data-type=\"page\" data-id=\"20\"><strong>\u0997\u09cd\u09b0\u09c7\u09a1 \u09ae\u09bf\u09b2\u09be\u09a8\u09cb\u09b0 \u099c\u09a8\u09cd\u09af \u0985\u09a8\u09c1\u09b0\u09cb\u09a7 \u0995\u09b0\u09c1\u09a8<\/strong> \u2014 share your fabric type, screen mesh, and printing speed for a specific grade recommendation<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%86%e0%a6%ae%e0%a6%be%e0%a6%a6%e0%a7%87%e0%a6%b0-%e0%a6%b8%e0%a6%be%e0%a6%a5%e0%a7%87-%e0%a6%af%e0%a7%8b%e0%a6%97%e0%a6%be%e0%a6%af%e0%a7%8b%e0%a6%97-%e0%a6%95%e0%a6%b0%e0%a7%81%e0%a6%a8\/\" data-type=\"page\" data-id=\"20\"><strong>\u0986\u09ae\u09be\u09a6\u09c7\u09b0 \u09aa\u09cd\u09b0\u09af\u09c1\u0995\u09cd\u09a4\u09bf\u0997\u09a4 \u09a6\u09b2\u09c7\u09b0 \u09b8\u09be\u09a5\u09c7 \u09af\u09cb\u0997\u09be\u09af\u09cb\u0997 \u0995\u09b0\u09c1\u09a8<\/strong> \u2014 for paste formulation support or screen printing troubleshoo<\/a>ting\ud83d\udce7 <strong>\u0987\u09ae\u09c7\u0987\u09b2<a href=\"https:\/\/fsxchemical.com\/bn\/%e0%a6%86%e0%a6%ae%e0%a6%be%e0%a6%a6%e0%a7%87%e0%a6%b0-%e0%a6%b8%e0%a6%be%e0%a6%a5%e0%a7%87-%e0%a6%af%e0%a7%8b%e0%a6%97%e0%a6%be%e0%a6%af%e0%a7%8b%e0%a6%97-%e0%a6%95%e0%a6%b0%e0%a7%81%e0%a6%a8\/\">: Service@fsxchemical.com<\/a><\/strong><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>","protected":false},"excerpt":{"rendered":"<p>\u09b8\u09cb\u09a1\u09bf\u09af\u09bc\u09be\u09ae \u0985\u09cd\u09af\u09be\u09b2\u099c\u09bf\u09a8\u09c7\u099f \u09ac\u09cd\u09af\u09ac\u09b9\u09be\u09b0 \u0995\u09b0\u09c7 \u09aa\u09cd\u09b0\u09a4\u09bf\u0995\u09cd\u09b0\u09bf\u09af\u09bc\u09be\u09b6\u09c0\u09b2 \u09b0\u099e\u09cd\u099c\u0995 \u09b8\u09cd\u0995\u09cd\u09b0\u09bf\u09a8 \u09aa\u09cd\u09b0\u09bf\u09a8\u09cd\u099f\u09bf\u0982\u09af\u09bc\u09c7\u09b0 \u099c\u09a8\u09cd\u09af \u09b8\u09a0\u09bf\u0995 \u09aa\u09c7\u09b7\u09cd\u099f \u09ab\u09b0\u09cd\u09ae\u09c1\u09b2\u09c7\u09b6\u09a8, \u09b8\u09be\u09a8\u09cd\u09a6\u09cd\u09b0\u09a4\u09be \u09a8\u09bf\u09af\u09bc\u09a8\u09cd\u09a4\u09cd\u09b0\u09a3 \u098f\u09ac\u0982 \u09ac\u09be\u09b7\u09cd\u09aa\u09be\u09af\u09bc\u09a8 \u09b6\u09b0\u09cd\u09a4 \u09aa\u09cd\u09b0\u09af\u09bc\u09cb\u099c\u09a8\u0964 \u098f\u0987 \u0997\u09be\u0987\u09a1\u09c7 \u09b8\u09ae\u09a4\u09b2 \u0993 \u0998\u09c2\u09b0\u09cd\u09a3\u09be\u09af\u09bc\u09ae\u09be\u09a8 \u09b8\u09cd\u0995\u09cd\u09b0\u09bf\u09a8\u09c7\u09b0 \u09aa\u09c7\u09b7\u09cd\u099f\u09c7\u09b0 \u09aa\u09cd\u09b0\u09af\u09bc\u09cb\u099c\u09a8\u09c0\u09af\u09bc\u09a4\u09be, \u0995\u09cd\u09b7\u09be\u09b0\u09c0\u09af\u09bc \u09b8\u09ae\u09af\u09bc\u0995\u09be\u09b2, \u09b8\u09be\u09a7\u09be\u09b0\u09a3 \u0989\u09ce\u09aa\u09be\u09a6\u09a8 \u09a4\u09cd\u09b0\u09c1\u099f\u09bf \u098f\u09ac\u0982 \u09aa\u09c7\u09b7\u09cd\u099f-\u09b8\u0982\u0995\u09cd\u09b0\u09be\u09a8\u09cd\u09a4 \u0995\u09be\u09b0\u09a3 \u09a8\u09bf\u09b0\u09cd\u09a3\u09af\u09bc\u09c7\u09b0 \u09aa\u09a6\u09cd\u09a7\u09a4\u09bf \u09ac\u09b0\u09cd\u09a3\u09a8\u09be \u0995\u09b0\u09be \u09b9\u09af\u09bc\u09c7\u099b\u09c7\u0964.<\/p>","protected":false},"author":1,"featured_media":8241,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_seopress_titles_title":"Sodium Alginate for Reactive Screen Printing","_seopress_titles_desc":"Prepare and troubleshoot sodium alginate paste for reactive flat and rotary screen printing. 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