{"id":11006,"date":"2026-03-09T10:26:00","date_gmt":"2026-03-09T10:26:00","guid":{"rendered":"https:\/\/fsxchemical.com\/?p=11006"},"modified":"2026-08-29T10:27:51","modified_gmt":"2026-08-29T10:27:51","slug":"rotary-screen-vs-flat-screen-thickener-rheology","status":"publish","type":"post","link":"https:\/\/fsxchemical.com\/vi\/blog\/rotary-screen-vs-flat-screen-thickener-rheology\/","title":{"rendered":"In l\u01b0\u1edbi quay so v\u1edbi in l\u01b0\u1edbi ph\u1eb3ng: Y\u00eau c\u1ea7u v\u1ec1 t\u00ednh l\u01b0u bi\u1ebfn c\u1ee7a ch\u1ea5t l\u00e0m \u0111\u1eb7c thay \u0111\u1ed5i nh\u01b0 th\u1ebf n\u00e0o"},"content":{"rendered":"<p class=\"wp-block-wd-paragraph wd-77a6d042\"><em>Flat-screen and rotary-screen textile printing both force color paste through patterned screen openings, but they do not expose the thickener to the same mechanical history. Flat-screen printing is typically a reciprocating, semi-continuous process in which a squeegee crosses a stationary screen and the screen is then lifted before the fabric advances. Rotary-screen printing is continuous: paste is supplied inside a rotating cylindrical screen while an internal squeegee or magnetic-rod system forces paste through the design at production speed. Because the paste experiences different shear, residence time, recovery and circulation conditions, the rheology that works on one machine may not transfer directly to the other. This guide explains how to compare low-shear body, shear thinning, elasticity, structural recovery and long-run stability before selecting a textile printing thickener.<\/em><\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-64e0e86e\">Same Screen-Printing Principle, Different Mechanical History<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-8f91c2f0\">Flat-screen and rotary-screen textile printing share the same basic principle:<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-12031bf6\"><strong>Printing paste is forced through open areas of a patterned screen and deposited on the fabric.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-b54b52a3\">But the mechanics are different.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-f94767be\">In flat-screen printing, a flat screen is placed over the fabric, a squeegee traverses the image area, the screen is lifted and the fabric advances to the next repeat.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-636a026a\">In rotary-screen printing, a cylindrical screen rotates continuously with the moving fabric while paste is supplied inside the screen and forced outward through the design openings.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-6f972768\">Textile process references describe flat-screen printing as a semi-continuous reciprocating process and rotary-screen printing as a continuous, higher-productivity process. Published rotary-screen research also shows that screen mesh, machine settings and print-paste rheology jointly affect paste deposit and penetration.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-8627e309\">This leads to the first important rule:<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-14e7966b\"><strong>The machine changes the shear history of the paste, so machine selection changes the rheology requirement.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-9aa1be23\">That does not mean every rotary paste must be thinner than every flat-screen paste.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-0edddcf1\">It means the complete flow-and-recovery profile must match the machine.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-896f06c4\">How Flat-Screen Printing Exposes the Paste to Shear<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-69efda60\">Flat-screen printing is usually intermittent.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-3dc66449\">A typical cycle is:<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-bf613567\"><strong>Screen Down \u2192 Squeegee Stroke \u2192 Paste Through Mesh \u2192 Screen Lift \u2192 Fabric Advance \u2192 Next Stroke<\/strong><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-4914468b\">During the squeegee stroke, the paste experiences significant shear as it moves across the screen and through the open mesh.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-e4b0d212\">After the stroke, however, part of the paste may remain relatively stationary on the screen before the next cycle.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-8e2e9073\">This creates several rheological demands:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Enough low-shear body to prevent uncontrolled spreading<\/li>\n\n\n\n<li>Good flow during the squeegee stroke<\/li>\n\n\n\n<li>Recovery after transfer<\/li>\n\n\n\n<li>Resistance to excessive paste drying or skinning during intermittent dwell<\/li>\n\n\n\n<li>Repeatable viscosity between successive strokes<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-baf88fab\">Flat-screen printing may therefore tolerate a different low-shear structure than a continuous rotary line, but the correct target depends on:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Automatic vs. manual flat screen<\/li>\n\n\n\n<li>Stroke speed<\/li>\n\n\n\n<li>Number of squeegee passes<\/li>\n\n\n\n<li>Screen open area<\/li>\n\n\n\n<li>Fabric absorbency<\/li>\n\n\n\n<li>Time between strokes<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-55054c68\">Do not reduce flat-screen rheology to a rule such as \u201cflat screen needs higher viscosity.\u201d<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-50e18a0d\">How Rotary-Screen Printing Exposes the Paste to Shear<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-a321110b\">Rotary-screen printing is continuous.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-bc7d7754\">The fabric travels under cylindrical screens while paste is continuously supplied inside each screen.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-3769aa37\">An internal blade, roller or magnetic-rod squeegee system forces paste through the pattern.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-c25d5bb1\">Commercial rotary systems are designed for high-volume production and consistent long runs.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-30939ced\">This creates a different operating history:<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-71902d62\"><strong>Feed \/ Circulation \u2192 Screen Interior \u2192 High Shear at Transfer Zone \u2192 Deposit on Moving Fabric \u2192 Continued Paste Residence and Recirculation<\/strong><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-3174c8ef\">The paste must therefore maintain useful rheology not only for one stroke but through a long, repeated mechanical history.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-978c9c1e\">Important risks include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Progressive viscosity drift<\/li>\n\n\n\n<li>Excessive shear thinning that does not recover<\/li>\n\n\n\n<li>Foam accumulation<\/li>\n\n\n\n<li>Evaporation during long runs<\/li>\n\n\n\n<li>Temperature rise<\/li>\n\n\n\n<li>Deposit variation from beginning to end<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-8906e537\">Rotary-screen production often makes long-run rheological stability more commercially visible because even a small change can affect many meters of fabric.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-604bd21c\">Why One Viscosity Number Cannot Define Machine Suitability<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-264503c8\">A Brookfield or rotational-viscometer value is useful only under a defined method.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-66b26b61\">It usually describes one point in the paste&#8217;s flow behavior.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-42e0115c\">Screen printing exposes paste to a range of shear rates.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-938fbe20\">Research on textile printing thickeners shows that both flow and viscoelastic properties are strongly connected with print-quality parameters, and screen-printing studies show that paste behavior changes substantially between low-shear rest conditions and the high-shear conditions present during passage through screen openings.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-3cd2f5ea\">Therefore, two pastes can both read:<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-8db6aaf5\"><strong>30,000 mPa\u00b7s<\/strong><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-485bdbd1\">under one test method and still behave differently in:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Pumping<\/li>\n\n\n\n<li>Squeegee transfer<\/li>\n\n\n\n<li>Mesh passage<\/li>\n\n\n\n<li>Ph\u1ee5c h\u1ed3i<\/li>\n\n\n\n<li>\u0110\u1ed9 th\u00e2m nh\u1eadp<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-2485aeeb\">The correct comparison is:<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-22576c7b\"><strong>Low-Shear Body + High-Shear Flow + Elasticity + Recovery + Holding Stability<\/strong><\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-84551b95\">1. Low-Shear Body: Holding the Pattern Before and After Transfer<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-748d1a07\">At low shear, the printing paste needs enough structure to resist uncontrolled movement.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-70d07b15\">This helps support:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Pattern definition<\/li>\n\n\n\n<li>Reduced bleeding<\/li>\n\n\n\n<li>Stable paste on the screen<\/li>\n\n\n\n<li>Controlled penetration<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-8bd38604\">For flat-screen printing, low-shear body can be especially visible during the interval between strokes.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-04cc550e\">For rotary screen, low-shear body remains important after the paste leaves the screen and before drying, but excessive rest viscosity can create problems in feed and transfer.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-74146965\">The correct target is therefore not maximum rest viscosity.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-39a87117\">It is enough structure to control the design without making the paste difficult to move.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-80dab367\">2. Shear Thinning: Flowing Through the Screen<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-5fff717f\">Textile printing pastes often need pseudoplastic or shear-thinning behavior.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-164ba5b2\">Under squeegee or screen-transfer shear, apparent viscosity decreases so the paste can move through the screen openings.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-5981b422\">Once shear is reduced, the paste can recover part of its original structure.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-3cb34c21\">Research on textile printing rheology summarizes the desired balance as:<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-80523f50\"><strong>Lower viscosity under high shear for application + Higher viscosity at low shear for pattern control<\/strong><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-fa87dd7e\">If shear thinning is too weak:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Transfer can be incomplete.<\/li>\n\n\n\n<li>Higher pressure may be needed.<\/li>\n\n\n\n<li>Screen filling can become poor.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-3e39d09d\">If shear thinning is excessive:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Paste can become too fluid during machine operation.<\/li>\n\n\n\n<li>Penetration can become excessive.<\/li>\n\n\n\n<li>Edges can soften.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-16279fcf\">Rotary lines often reveal excessive long-duration shear thinning more quickly because the paste experiences repeated continuous shear.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-b080c029\">3. Structural Recovery: What Happens After the Paste Leaves the Screen?<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-0522235a\">After the paste passes through the screen, the shear rate drops sharply.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-dacc2495\">The paste should recover enough structure to stop uncontrolled lateral flow.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-b4895940\">Recovery that is too slow can lead to:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Bleeding<\/li>\n\n\n\n<li>Blurred fine lines<\/li>\n\n\n\n<li>Haloing<\/li>\n\n\n\n<li>Excess penetration<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-e5c98c2f\">Recovery that is too fast or too strong can also create problems if the paste does not level sufficiently after transfer.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-66025b63\">This can contribute to:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Uneven solid areas<\/li>\n\n\n\n<li>Surface texture<\/li>\n\n\n\n<li>Poor penetration<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-9e5c71cd\">Flat and rotary machines can therefore prefer different recovery windows depending on:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Fabric speed<\/li>\n\n\n\n<li>Time before drying<\/li>\n\n\n\n<li>L\u1edbp l\u1eafng \u0111\u1ecdng d\u1ea1ng b\u1ed9t nh\u00e3o<\/li>\n\n\n\n<li>Design coverage<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-bc371c4e\">Structural recovery should be evaluated on the actual machine, not inferred from static viscosity.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-fc43b567\">4. Elasticity and Stringiness<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-d2ee78b5\">Viscoelasticity affects how printing paste deforms and separates from the screen.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-eebf0b7d\">Some elasticity can support recovery.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-28d716a6\">Too much elasticity can create:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Stringiness<\/li>\n\n\n\n<li>Poor screen release<\/li>\n\n\n\n<li>Uneven deposit<\/li>\n\n\n\n<li>Tail or edge defects<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-48315729\">Published textile-thickener research notes that elasticity influences both passage through screen openings and subsequent flow through textile fibers.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-3f60ebb6\">This property can become especially important when transferring a formula between flat and rotary machines because screen separation mechanics differ.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-17068ea1\">Do not assume a highly elastic paste that performs well on one machine will automatically release cleanly on the other.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-e3d66421\">5. Long-Run Stability: Why Rotary Often Exposes Hidden Weaknesses<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-3c4e509a\">Rotary-screen printing is designed for continuous high-volume production.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-7455be42\">That means a paste may remain in the machine system for an extended period while experiencing:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Repeated shear<\/li>\n\n\n\n<li>Circulation<\/li>\n\n\n\n<li>Mechanical pumping<\/li>\n\n\n\n<li>Air incorporation<\/li>\n\n\n\n<li>Temperature variation<\/li>\n\n\n\n<li>Evaporation<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-0a7e6de0\">A useful rotary-screen paste should therefore be checked at:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Start of run<\/li>\n\n\n\n<li>After a defined production interval<\/li>\n\n\n\n<li>Mid-run<\/li>\n\n\n\n<li>Near the end of the intended production window<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-343a8d52\">So s\u00e1nh:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u0110\u1ed9 nh\u1edbt<\/li>\n\n\n\n<li>B\u1ecdt<\/li>\n\n\n\n<li>Screen running<\/li>\n\n\n\n<li>Hi\u1ec7u su\u1ea5t m\u00e0u<\/li>\n\n\n\n<li>Pattern definition<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-e746f357\">A paste that gives an excellent 10-meter sample but drifts after 1,000 meters has not passed a realistic rotary-screen qualification.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-6e5d65c6\">6. Intermittent Dwell: Why Flat-Screen Paste Can Fail Differently<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-6e7824d2\">Flat-screen printing introduces intermittent waiting periods.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-4faf0db6\">During these periods, paste on the screen can:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Lose water at the surface<\/li>\n\n\n\n<li>Become locally thicker<\/li>\n\n\n\n<li>Dry around fine openings<\/li>\n\n\n\n<li>Change transfer between strokes<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-9fd7a30f\">This creates defects such as:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Fine-mesh blocking<\/li>\n\n\n\n<li>Uneven first stroke after a pause<\/li>\n\n\n\n<li>Increasing squeegee pressure requirement<\/li>\n\n\n\n<li>Pattern inconsistency after machine stops<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-94dc7b4c\">For flat-screen production, evaluate pause\/restart behavior in addition to continuous printing behavior.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-1d646a56\">A useful trial can include a controlled machine stop followed by a restart to see whether paste recovery and screen openness remain acceptable.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-8f129472\">Paste Deposit and Penetration<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-81460a6c\">Machine type changes how paste is deposited onto and into the fabric.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-a02180d0\">Rotary-screen research has shown that paste application and penetration are affected jointly by:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Screen mesh<\/li>\n\n\n\n<li>Machine settings<\/li>\n\n\n\n<li>Paste rheology<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-2470bd67\">The same thickener can therefore give different:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Wet pickup<\/li>\n\n\n\n<li>\u0110\u1ed9 th\u00e2m nh\u1eadp<\/li>\n\n\n\n<li>Surface color<\/li>\n\n\n\n<li>K\/S<\/li>\n\n\n\n<li>\u0110\u1ed9 s\u1eafc n\u00e9t khi in<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-592d0f4e\">when moved between flat and rotary machines.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-8550f8f0\">When transferring a formula, do not adjust viscosity alone.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-acf8739e\">Measure or observe the printed paste deposit and final penetration.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-ce4f2c1a\">Screen Mesh and Squeegee Settings Still Matter<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-b1cb6453\">Machine architecture is only one part of the system.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-80e47bec\">Screen mesh, engraving\/open area, squeegee pressure, squeegee type and speed also change the shear and deposit.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-fd88b005\">For this article, the important principle is:<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-f1550238\"><strong>Machine Type \u00d7 Screen Geometry \u00d7 Squeegee Conditions \u00d7 Paste Rheology = Printing Result<\/strong><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-a2555d16\">A thickener should not be labeled \u201crotary grade\u201d or \u201cflat-screen grade\u201d without knowing the screen and machine conditions.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-d4ba4bc7\">Fine mesh can require easier high-shear flow than an open design.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-16410bf1\">Higher pressure can force more paste through the screen and change penetration.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-5c5d4e12\">These variables should be recorded during grade matching.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-6d2326d9\">Fabric Construction Changes the Required Rheology<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-586b004c\">The same flat or rotary machine can require different paste behavior on different fabrics.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-603ca9ba\">Important variables include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Woven vs. knitted<\/li>\n\n\n\n<li>Fabric weight<\/li>\n\n\n\n<li>Surface hairiness<\/li>\n\n\n\n<li>Absorbency<\/li>\n\n\n\n<li>Stretch<\/li>\n\n\n\n<li>Open vs. dense construction<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-a994864b\">A highly absorbent cotton fabric may pull paste rapidly into the structure.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-f2c30889\">A smooth polyester surface can retain more paste at the surface.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-bd1f556a\">Therefore, machine comparison should always be made on the same fabric when possible.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-eaec36be\">Otherwise, fabric effects can be mistaken for rheology effects.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-bdace3a1\">In b\u1eb1ng thu\u1ed1c nhu\u1ed9m ph\u1ea3n \u1ee9ng<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-2c38f393\">Reactive printing pastes often use sodium alginate or other carefully selected thickeners for cellulosic fabrics.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-9b654368\">When moving from flat to rotary screen, evaluate:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Complete-paste viscosity after dye and alkali<\/li>\n\n\n\n<li>Shear thinning<\/li>\n\n\n\n<li>Fine-line definition<\/li>\n\n\n\n<li>\u0110\u1ed9 th\u00e2m nh\u1eadp<\/li>\n\n\n\n<li>Color yield after steaming<\/li>\n\n\n\n<li>R\u1eeda tr\u00f4i<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-53a164ac\">The same sodium alginate concentration may need adjustment if the rotary machine produces a different deposit or penetration.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-f63f4447\">However, do not make a dosage change before measuring the actual print result.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-ce10e024\">In ph\u00e2n t\u00e1n<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-6e1125e0\">Polyester disperse screen printing adds another requirement: the thickener must release the dye effectively during thermal fixation.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-0f832423\">A paste can run well on a rotary screen but still reduce final K\/S if the thickener film restricts dye release.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-cc81e568\">When comparing flat and rotary disperse printing, check:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Duy tr\u00ec s\u1ef1 \u1ed5n \u0111\u1ecbnh<\/li>\n\n\n\n<li>Screen running<\/li>\n\n\n\n<li>Printed deposit<\/li>\n\n\n\n<li>C\u1ed1 \u0111\u1ecbnh b\u1eb1ng nhi\u1ec7t<\/li>\n\n\n\n<li>Final K\/S<\/li>\n\n\n\n<li>Wash-off \/ reduction clearing<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-cfeed4f5\">Machine rheology and thermal-fixation performance must both pass.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-6b141b3b\">In b\u1eb1ng m\u1ef1c m\u00e0u<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-f0100ce2\">Pigment printing adds binder to the rheology problem.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-2ecdcbb6\">The complete paste may contain:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Dung d\u1ecbch ph\u00e2n t\u00e1n s\u1eafc t\u1ed1<\/li>\n\n\n\n<li>Binder<\/li>\n\n\n\n<li>Ch\u1ea5t l\u00e0m \u0111\u1eb7c<\/li>\n\n\n\n<li>Fixer<\/li>\n\n\n\n<li>Auxiliaries<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-6c01546f\">When changing machine type, evaluate whether the binder\/thickener system maintains:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Chuy\u1ec3n h\u00ecnh \u1ea3nh l\u00ean m\u00e0n h\u00ecnh<\/li>\n\n\n\n<li>Pattern definition<\/li>\n\n\n\n<li>Duy tr\u00ec s\u1ef1 \u1ed5n \u0111\u1ecbnh<\/li>\n\n\n\n<li>Curing performance<\/li>\n\n\n\n<li>V\u1ea3i d\u1ec7t tay<\/li>\n\n\n\n<li>\u0110\u1ed9 b\u1ec1n khi c\u1ecd x\u00e1t<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-f791ea95\">Do not increase thickener only to solve a machine-transfer problem if the extra polymer solids worsen hand after curing.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-39640f2a\">How to Transfer a Paste from Flat Screen to Rotary Screen<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-00037e7d\">Do not begin by changing several formulation variables at once.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-659cefd7\">Step 1: Use the Existing Flat-Screen Paste as the Reference<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-81d9ea91\">B\u1ea3n ghi:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Thickener grade<\/li>\n\n\n\n<li>N\u1ed3ng \u0111\u1ed9<\/li>\n\n\n\n<li>Viscosity method<\/li>\n\n\n\n<li>V\u1ea3i<\/li>\n\n\n\n<li>Screen<\/li>\n\n\n\n<li>Squeegee conditions<\/li>\n\n\n\n<li>Printed result<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-29440d1e\">Step 2: Run the Same Paste on Rotary at Controlled Speed<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-84713c04\">Observe:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Feed stability<\/li>\n\n\n\n<li>\u0110o\u1ea1n tr\u00edch tr\u00ean m\u00e0n h\u00ecnh<\/li>\n\n\n\n<li>Deposit<\/li>\n\n\n\n<li>Pattern definition<\/li>\n\n\n\n<li>\u0110\u1ed9 th\u00e2m nh\u1eadp<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-11dca591\">Step 3: Check Long-Run Change<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-a65df567\">Recheck paste and print after a meaningful production interval.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-b99aa0df\">Step 4: Adjust One Rheology Variable at a Time<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-cc40ce17\">Possible directions include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Thickener concentration<\/li>\n\n\n\n<li>Grade \/ molecular structure<\/li>\n\n\n\n<li>Compound-thickener ratio<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-abf95898\">Do not assume the rotary version simply needs a lower viscosity.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-b1c6cd09\">How to Transfer a Paste from Rotary Screen to Flat Screen<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-ab9afb3a\">The reverse transfer requires a different check.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-d51c6ac5\">A paste optimized for continuous rotary running may show:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Too much spreading during flat-screen dwell<\/li>\n\n\n\n<li>Different recovery after the squeegee stroke<\/li>\n\n\n\n<li>Screen drying during pauses<\/li>\n\n\n\n<li>Different paste deposit from multiple strokes<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-5c78bab8\">Run the same paste first, then evaluate whether:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Low-shear body needs adjustment<\/li>\n\n\n\n<li>Recovery needs adjustment<\/li>\n\n\n\n<li>Water retention needs improvement<\/li>\n\n\n\n<li>The number of squeegee strokes should change<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-7bb143b4\">Again, change the minimum number of variables needed to identify the cause.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-c4c5584f\">Laboratory Rheology Test Plan<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-8f994964\">For a technical comparison, use the complete printing paste rather than the thickener stock solution alone.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-4f74d914\">At minimum, standardize:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Thickener concentration<\/li>\n\n\n\n<li>N\u01b0\u1edbc<\/li>\n\n\n\n<li>Dye\/pigment\/binder formula<\/li>\n\n\n\n<li>Nhi\u1ec7t \u0111\u1ed9<\/li>\n\n\n\n<li>B\u1ed5 sung n\u01b0\u1edbc<\/li>\n\n\n\n<li>Th\u1eddi gian gi\u1eef<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-a231eaa0\">\u0110\u01a1n v\u1ecb \u0111o l\u01b0\u1eddng:<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-852b9ff0\">Low-Shear Viscosity<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-6461a9b6\">Represents paste body during storage\/rest conditions.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-74c7e70c\">Higher-Shear Viscosity<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-da543680\">Shows how easily the paste flows under application stress.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-9d91ab12\">Ph\u1ee5c h\u1ed3i<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-5e67b227\">Measure whether viscosity\/structure rebuilds after a high-shear interval.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-f41c32bd\">Viscoelasticity Where Equipment Is Available<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-15c0f064\">Storage\/loss response can help identify excessively elastic or weak-gel behavior.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-40ddddc3\">If the mill does not have a rheometer, build a practical correlation using:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Multiple viscometer speeds<\/li>\n\n\n\n<li>Controlled high-speed mixing<\/li>\n\n\n\n<li>Recovery measurement after mixing<\/li>\n\n\n\n<li>Standardized screen-print trials<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-0c8451b3\">The laboratory target is to reproduce machine-relevant behavior, not to generate rheology data with no production connection.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-5e01e518\">Production Trial and Approval Criteria<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-92e2c8f2\">Approve a thickener for flat or rotary screen only after production-scale validation.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-662269f6\">B\u1ea3n ghi:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Machine type<\/li>\n\n\n\n<li>T\u1ed1c \u0111\u1ed9 m\u00e1y<\/li>\n\n\n\n<li>Screen specification<\/li>\n\n\n\n<li>Squeegee type\/settings<\/li>\n\n\n\n<li>Fabric lot<\/li>\n\n\n\n<li>Paste batch<\/li>\n\n\n\n<li>Starting viscosity<\/li>\n\n\n\n<li>\u0110\u1ed9 nh\u1edbt gi\u1eefa chu k\u1ef3<\/li>\n\n\n\n<li>\u0110\u1ed9 nh\u1edbt khi ch\u1ea3y qua khe h\u1edf<\/li>\n\n\n\n<li>Print quality<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-c384c6e7\">\u0110\u00e1nh gi\u00e1:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Beginning-to-end shade consistency<\/li>\n\n\n\n<li>Pattern definition<\/li>\n\n\n\n<li>\u0110\u1ed9 th\u00e2m nh\u1eadp<\/li>\n\n\n\n<li>Screen cleanliness<\/li>\n\n\n\n<li>B\u1ecdt<\/li>\n\n\n\n<li>S\u1ef1 gi\u00e1n \u0111o\u1ea1n do m\u00e1y m\u00f3c<\/li>\n\n\n\n<li>Final K\/S \/ fastness \/ hand after full processing<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-e46ad366\">The approval target should be an operating window, not one perfect sample.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-2c8838a1\">Troubleshooting Flat vs. Rotary Screen Problems<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>V\u1ea5n \u0111\u1ec1 \u0111\u01b0\u1ee3c ghi nh\u1eadn<\/th><th>C\u00e1c bi\u1ebfn c\u1ea7n ki\u1ec3m tra tr\u01b0\u1edbc ti\u00ean<\/th><th>\u0110\u1eebng v\u1ed9i k\u1ebft lu\u1eadn<\/th><\/tr><\/thead><tbody><tr><td>Paste works on flat but spreads on rotary<\/td><td>Shear thinning, recovery, deposit, machine speed<\/td><td>Rotary always needs a thicker paste<\/td><\/tr><tr><td>Paste works on flat but transfers poorly on rotary<\/td><td>High-shear flow, screen geometry, feed stability<\/td><td>Higher squeegee pressure is the only solution<\/td><\/tr><tr><td>Paste works on rotary but blocks during flat-screen pauses<\/td><td>Water retention, surface drying, dwell time<\/td><td>The thickener is unsuitable in all flat-screen systems<\/td><\/tr><tr><td>Rotary quality drifts during a long run<\/td><td>Shear history, temperature, foam, evaporation, holding stability<\/td><td>The initial viscosity proves long-run stability<\/td><\/tr><tr><td>Same viscosity gives different penetration<\/td><td>Screen, squeegee, rheology, fabric<\/td><td>Same Brookfield value means same application<\/td><\/tr><tr><td>Fine lines improve but solid areas become uneven<\/td><td>Recovery, leveling, paste deposit<\/td><td>Maximum structural recovery is always best<\/td><\/tr><tr><td>Machine transfer improves but final color drops<\/td><td>Deposit, dye mobility, fixation, wash-off<\/td><td>Machine rheology alone defines product suitability<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-9a18d5b9\">T\u1ed5ng chi ph\u00ed trong qu\u00e1 tr\u00ecnh s\u1eed d\u1ee5ng<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-d3698674\">Machine-specific rheology affects more than print quality.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-e7c6c98b\">Bao g\u1ed3m:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Li\u1ec1u l\u01b0\u1ee3ng ch\u1ea5t l\u00e0m \u0111\u1eb7c<\/li>\n\n\n\n<li>Paste preparation<\/li>\n\n\n\n<li>Pumping energy<\/li>\n\n\n\n<li>T\u1ed1c \u0111\u1ed9 m\u00e1y<\/li>\n\n\n\n<li>Screen interruptions<\/li>\n\n\n\n<li>Waste paste<\/li>\n\n\n\n<li>S\u1eeda l\u1ea1i<\/li>\n\n\n\n<li>Final washing or curing<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-0c48a8de\">A useful framework is:<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-1c55246b\"><strong>Total Cost in Use = Thickener Cost + Preparation + Machine Efficiency + Downtime + Post-Treatment + Rework + Quality Loss<\/strong><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-0e75224a\">A thickener that costs more per kilogram can be the lower-cost rotary route if it maintains long-run viscosity and reduces interruptions.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-dcfa1c34\">A lower-cost product can be the better flat-screen route if it provides stable print definition without drying on the screen.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-371ca18d\">Compare cost per acceptable printed meter, not powder price alone.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-da4ace62\">B\u1ea1n n\u00ean cung c\u1ea5p nh\u1eefng th\u00f4ng tin n\u00e0o cho nh\u00e0 cung c\u1ea5p ch\u1ea5t l\u00e0m \u0111\u1eb7c?<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-fef6317d\">For useful flat-vs-rotary grade matching, provide:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>R\u00e2y ph\u1eb3ng ho\u1eb7c r\u00e2y quay<\/li>\n\n\n\n<li>Machine manufacturer\/model where relevant<\/li>\n\n\n\n<li>T\u1ed1c \u0111\u1ed9 s\u1ea3n xu\u1ea5t<\/li>\n\n\n\n<li>Screen mesh\/engraving<\/li>\n\n\n\n<li>Squeegee type and settings<\/li>\n\n\n\n<li>Fabric composition and construction<\/li>\n\n\n\n<li>Dye\/pigment route<\/li>\n\n\n\n<li>Current thickener product\/TDS<\/li>\n\n\n\n<li>Li\u1ec1u l\u01b0\u1ee3ng hi\u1ec7n t\u1ea1i<\/li>\n\n\n\n<li>Viscosity and full test method<\/li>\n\n\n\n<li>Complete or simplified formula<\/li>\n\n\n\n<li>Th\u1eddi gian gi\u1eef keo<\/li>\n\n\n\n<li>Current defect: spreading, transfer, blocking, drift, penetration or cost<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-32d9a641\">FSX Chemical c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng th\u00f4ng tin n\u00e0y th\u00f4ng qua <a href=\"https:\/\/fsxchemical.com\/vi\/dich-vu\/cac-mau-trung-khop\/\">M\u1eabu v\u00e0 vi\u1ec7c k\u1ebft h\u1ee3p<\/a> to compare sodium alginate, CMC, CMS or other route-appropriate thickeners under matched machine conditions.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-cb8d7ae4\">How Should Thickener Rheology Be Matched to Flat or Rotary Screen?<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-6c26afdd\">M\u1ed9t chu\u1ed7i quy\u1ebft \u0111\u1ecbnh th\u1ef1c ti\u1ec5n l\u00e0:<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-7833518d\"><strong>Machine Mechanics \u2192 Shear History \u2192 Low-Shear Body \u2192 High-Shear Flow \u2192 Recovery \u2192 Paste Deposit \u2192 Finished Print \u2192 Long-Run Repeatability<\/strong><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-55e59abe\">C\u00e1c nguy\u00ean t\u1eafc ch\u00ednh l\u00e0:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Flat and rotary screen use the same transfer principle but expose paste to different mechanical histories.<\/strong><\/li>\n\n\n\n<li><strong>Same viscosity does not mean the same flow, recovery or machine behavior.<\/strong><\/li>\n\n\n\n<li><strong>Rotary production places strong emphasis on continuous shear and long-run stability.<\/strong><\/li>\n\n\n\n<li><strong>Flat-screen production adds intermittent dwell, pause\/restart and screen-drying risks.<\/strong><\/li>\n\n\n\n<li><strong>Screen mesh, squeegee and fabric must be recorded before changing the thickener.<\/strong><\/li>\n\n\n\n<li><strong>The final acceptance standard is stable production and finished-print quality\u2014not a viscosity number alone.<\/strong><\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-f6c09d9e\">C\u00e1c c\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p<\/h2>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-95d65a6d\">1. Does rotary-screen printing need lower-viscosity paste than flat-screen printing?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-d7977925\">Not as a universal rule. Rotary printing often needs excellent high-shear flow and long-run stability, while flat screen can place more emphasis on low-shear hold and pause\/restart behavior. Test the actual machine.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-66c9aeda\">2. Why can the same paste work on flat screen but fail on rotary screen?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-ba67e4c5\">Rotary printing exposes the paste to continuous feed, repeated shear, circulation and longer machine residence. A paste can therefore drift or thin differently during a long run.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-cc0ebedf\">3. Why can a rotary paste fail on flat screen?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-cc37ffa4\">Flat-screen dwell between strokes can expose weak low-shear body, slow structural recovery or surface drying that was less visible on the continuous rotary line.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-08d7f1f6\">4. Is Brookfield viscosity enough to select a thickener?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-2ad2fae9\">No. It should be combined with shear-thinning, recovery, elasticity and machine-print testing.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-8eed4baa\">5. What rheology is generally useful for screen printing?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-09fec3a3\">A useful paste often has sufficient viscosity at low shear, lower apparent viscosity under application shear and enough recovery after transfer to control spreading.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-05e6cc7e\">6. Does faster rotary speed always require lower paste viscosity?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-1d4b8821\">No. Speed changes shear, residence and deposit conditions, but the correct adjustment can involve rheology, screen specification, squeegee settings or thickener grade\u2014not viscosity alone.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-20c06bd6\">7. Why does rotary print quality change from the beginning to the end of a run?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-5496baaa\">Check repeated shear, paste temperature, evaporation, foam, holding stability and feed conditions.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-079baf68\">8. Why does flat-screen paste dry in the screen?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-593c3e20\">Possible causes include long dwell, low humidity, excessive paste concentration, poor water retention or fine mesh. Diagnose the complete system.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-0d57d4ff\">9. Does higher structural recovery always give sharper printing?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-4a0d12be\">No. Excessively fast or strong recovery can reduce leveling and cause uneven solid areas. The target is a balanced recovery window.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-c6085344\">10. Can the same sodium alginate grade be used for both flat and rotary reactive printing?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-057f6e16\">Often it can be evaluated on both, but concentration and process settings may need adjustment. Approve the grade on each machine.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-5231fbf1\">11. Should I change thickener before changing screen or squeegee settings?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-f6bdf72e\">Not automatically. Machine settings and rheology interact. Record the current screen\/squeegee conditions and change one major variable at a time.<\/p>\n\n\n\n<h3 class=\"wp-block-wd-title title wd-53a48e4c\">12. What should I send FSX Chemical for flat-vs-rotary matching?<\/h3>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-7382e71d\">Send machine type, speed, screen, squeegee conditions, fabric, dye route, current thickener, dosage, viscosity method, formula and the current machine defect.<\/p>\n\n\n\n<h2 class=\"wp-block-wd-title title wd-7693ca62\">Match Thickener Rheology to Your Flat or Rotary Screen<\/h2>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-c5b5c172\">If the same printing paste behaves differently after moving between flat and rotary screen machines, FSX Chemical can help determine whether the next trial should focus on thickener grade, concentration, shear recovery or machine\/process conditions.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-979d1417\">For a useful technical comparison, send:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Your current thickener sample, TDS or COA<\/li>\n\n\n\n<li>R\u00e2y ph\u1eb3ng ho\u1eb7c r\u00e2y quay<\/li>\n\n\n\n<li>T\u1ed1c \u0111\u1ed9 m\u00e1y<\/li>\n\n\n\n<li>Screen mesh\/engraving<\/li>\n\n\n\n<li>Squeegee type\/settings<\/li>\n\n\n\n<li>Fabric composition and construction<\/li>\n\n\n\n<li>Dye\/pigment route<\/li>\n\n\n\n<li>Current thickener dosage<\/li>\n\n\n\n<li>\u0110\u1ed9 nh\u1edbt v\u00e0 ph\u01b0\u01a1ng ph\u00e1p th\u1eed nghi\u1ec7m to\u00e0n di\u1ec7n<\/li>\n\n\n\n<li>Complete or simplified formula<\/li>\n\n\n\n<li>Th\u1eddi gian gi\u1eef keo<\/li>\n\n\n\n<li>Current screen-running, spreading, penetration, color or cost target<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-f2c73d51\">B\u1eaft \u0111\u1ea7u b\u1eb1ng <a href=\"https:\/\/fsxchemical.com\/vi\/dich-vu\/cac-mau-trung-khop\/\">M\u1eabu v\u00e0 vi\u1ec7c k\u1ebft h\u1ee3p<\/a> for a controlled machine comparison.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-1e9ee2a9\">\u0110\u00e1nh gi\u00e1 <a href=\"https:\/\/fsxchemical.com\/vi\/product\/alginat-natri\/\">Alginat natri<\/a>, <a href=\"https:\/\/fsxchemical.com\/vi\/product\/carboxymethyl-cellulose-cmc\/\">CMC<\/a>, <a href=\"https:\/\/fsxchemical.com\/vi\/product\/tinh-bot-carboxymethyl-cms\/\">CMS<\/a> v\u00e0 <a href=\"https:\/\/fsxchemical.com\/vi\/product\/hon-hop-in-ky-thuat-so\/\">H\u1ed7n h\u1ee3p in k\u1ef9 thu\u1eadt s\u1ed1<\/a> for route-specific thickener information.<\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-1949c9fa\">B\u1ea1n c\u0169ng c\u00f3 th\u1ec3 <a href=\"https:\/\/fsxchemical.com\/vi\/dich-vu\/yeu-cau-bao-gia\/\">Y\u00eau c\u1ea7u b\u00e1o gi\u00e1 tr\u1ef1c ti\u1ebfp t\u1eeb nh\u00e0 m\u00e1y<\/a> after the suitable rheology route is confirmed or <a href=\"https:\/\/fsxchemical.com\/vi\/lien-he-voi-chung-toi\/\">Li\u00ean h\u1ec7 v\u1edbi FSX Chemical<\/a> \u0111\u1ec3 th\u1ea3o lu\u1eadn v\u1ec1 c\u00e1c v\u1ea5n \u0111\u1ec1 k\u1ef9 thu\u1eadt\ud83d\udce7\u00a0<strong>Email<a href=\"https:\/\/fsxchemical.com\/vi\/lien-he-voi-chung-toi\/\">: Service@fsxchemical.com<\/a><\/strong><\/p>\n\n\n\n<p class=\"wp-block-wd-paragraph wd-9a22b709\"><strong>The most useful question is not \u201cWhich viscosity is best for rotary or flat screen?\u201d It is \u201cWhat rheological profile gives stable transfer, recovery and print quality under this machine&#8217;s real shear history?\u201d<\/strong><\/p>","protected":false},"excerpt":{"rendered":"<p>In l\u1ee5a ph\u1eb3ng v\u00e0 in l\u1ee5a quay \u0111\u1ec1u d\u1ef1a tr\u00ean c\u00f9ng m\u1ed9t nguy\u00ean l\u00fd truy\u1ec1n d\u1eabn c\u01a1 b\u1ea3n, nh\u01b0ng h\u1ed7n h\u1ee3p m\u1ef1c in ph\u1ea3i ch\u1ecbu c\u00e1c \u0111i\u1ec1u ki\u1ec7n c\u1eaft v\u00e0 th\u1eddi gian l\u01b0u kh\u00e1c nhau. Do \u0111\u00f3, vi\u1ec7c l\u1ef1a ch\u1ecdn ch\u1ea5t l\u00e0m \u0111\u1eb7c ph\u00f9 h\u1ee3p c\u1ea7n d\u1ef1a tr\u00ean c\u00e1c y\u1ebfu t\u1ed1 nh\u01b0 \u0111\u1ed9 b\u1ec1n c\u1eaft th\u1ea5p, kh\u1ea3 n\u0103ng ch\u1ea3y \u1edf \u0111i\u1ec1u ki\u1ec7n c\u1eaft cao, kh\u1ea3 n\u0103ng ph\u1ee5c h\u1ed3i, \u0111\u1ed9 \u0111\u00e0n h\u1ed3i v\u00e0 \u0111\u1ed9 \u1ed5n \u0111\u1ecbnh c\u1ee7a m\u00e1y, ch\u1ee9 kh\u00f4ng ch\u1ec9 d\u1ef1a v\u00e0o \u0111\u1ed9 nh\u1edbt.<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_seopress_titles_title":"Rotary Screen vs. Flat Screen Printing: How Thickener Rheology Requirements Change","_seopress_titles_desc":"Learn how flat and rotary screen printing change thickener rheology requirements, including shear thinning, recovery, screen transfer, penetration and long-run stability.","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"","footnotes":""},"categories":[1],"tags":[1184,395,1381,1183,1126,1506,1369],"class_list":["post-11006","post","type-post","status-publish","format-standard","hentry","category-technical-guides","tag-flat-screen-printing","tag-printing-paste","tag-rheology","tag-rotary-screen-printing","tag-screen-printing","tag-shear-thinning","tag-textile-thickener"],"acf":[],"_links":{"self":[{"href":"https:\/\/fsxchemical.com\/vi\/wp-json\/wp\/v2\/posts\/11006","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fsxchemical.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fsxchemical.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fsxchemical.com\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fsxchemical.com\/vi\/wp-json\/wp\/v2\/comments?post=11006"}],"version-history":[{"count":2,"href":"https:\/\/fsxchemical.com\/vi\/wp-json\/wp\/v2\/posts\/11006\/revisions"}],"predecessor-version":[{"id":11008,"href":"https:\/\/fsxchemical.com\/vi\/wp-json\/wp\/v2\/posts\/11006\/revisions\/11008"}],"wp:attachment":[{"href":"https:\/\/fsxchemical.com\/vi\/wp-json\/wp\/v2\/media?parent=11006"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fsxchemical.com\/vi\/wp-json\/wp\/v2\/categories?post=11006"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fsxchemical.com\/vi\/wp-json\/wp\/v2\/tags?post=11006"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}