This article introduces the process optimization method of heating coating machines in the preparation of lithium battery electrodes. Key points include temperature control, recommending a gradient setting of 80°C at the front section and 110°C at the rear section. Coating speed starts at 2-5 meters per minute and is gradually adjusted until the density deviation is below 1.5%. Different adjustment methods are selected for coating thickness based on the range. It also mentions improving uniformity by adjusting the gap between blades, real-time monitoring, and slurry treatment. For the drying curve, multi-stage heating is recommended to avoid bubble issues. Overall optimization is based on existing standards and experimental data.

2026-05-15

This paper studies the effect of coating speed on film thickness uniformity in an adjustable film applicator. The experiment fixed the coating blade gap at 100 μm and used a resin solution with a viscosity of 200 mPa·s to prepare and measure films at five different speeds ranging from 10 to 80 mm/s. The results show that the lower the speed, the closer the film thickness is to the set value and the better the uniformity. When the speed exceeds 60 mm/s, the film thickness deviates significantly, and the uniformity decreases markedly, due to fluctuations caused by shear stress, inertial effects, and creep effects at high speeds. It is recommended to control the speed below 20 mm/s to achieve high uniformity.

2026-05-15

This article analyzes the causes of coating stripes caused by tension fluctuations in roll-to-roll laboratory coaters and proposes corresponding countermeasures. Tension variations cause substrate expansion and contraction, resulting in bright and dark stripes, with their spacing correlated to the fluctuation cycle of mechanical components. Key parameters include coating speed, liquid viscosity, and oven temperature. Solutions involve optimizing the mechanical system, such as adding inertia compensation rollers and using dual closed-loop control, and adjusting the process, such as improving liquid leveling properties and oven temperature. Detection methods include online thickness measurement and spectrum analysis. Actual cases show that replacing encoders or using fresh liquid can effectively reduce stripes.

2026-05-14

This article introduces common defects in the scraping process of laboratory coaters, such as streaks, orange peel, bubbles, uneven thickness, and skipped coating. It analyzes the causes of these issues, which are primarily related to material properties, operating parameters, and environmental factors. The article then presents methods for adjusting process parameters, including key variables such as doctor blade pressure, coating gap, speed, substrate tension, and slurry viscosity, and provides two commonly used formulas to assist in adjusting the wet film thickness and drying time of the coating. Finally, the article recommends a step-by-step troubleshooting approach, starting from substrate cleaning and doctor blade condition to gradually adjusting parameters in order to progressively eliminate defects.

2026-05-14

This article investigates the effect of spin-coating speed gradient on film thickness. Based on fluid mechanics and the Meyerhofer model, experiments have found that as the speed gradient increases, the film thickness decreases. For example, when the gradient rises from 500 rpm/s to 3000 rpm/s, the film thickness drops from 312 nanometers to 205 nanometers. However, an excessively large gradient may lead to uneven film thickness distribution. The article recommends selecting an appropriate gradient based on the target film thickness and adjusting process parameters by considering factors such as solution viscosity and ambient humidity.

2026-05-14

This article mainly discusses the different requirements of peel testing and tear testing for the selection of single-column testing machines. Peel testing targets adhesive surfaces, requires small force values, and needs high-speed loading and specialized fixtures; tear testing focuses on the propagation of cracks within the material, requires larger force values, and demands higher speed stability. When selecting a machine, factors such as sensor range, speed control, fixture design, data acquisition frequency, and frame structure should be considered. It is recommended to choose modular equipment to accommodate various testing needs.

2026-05-11

This article compares the differences between double-column portal and single-column universal testing machines in plastic and rubber testing. The double-column portal type offers high rigidity and large load capacity, making it suitable for high-strength materials and high-precision testing. The single-column type features an open structure and lower cost, making it ideal for scenarios with small loads and frequent fixture changes. The selection depends on load requirements, testing precision, and budget.

2026-05-11

This article introduces how to select a single-column electronic universal testing machine based on the maximum test force. First, determine the strength range according to the material type and standards, such as plastics, metals, etc. Then, calculate the maximum force using tensile strength and specimen area, and multiply it by a safety factor of 1.3 to 1.5. When selecting a model, ensure that the daily test force falls between 20% and 80% of the machine's range to maintain accuracy. Additionally, consider the frame stiffness and test space. If the force value exceeds 30 kN, it is recommended to switch to a dual-column model. Finally, a four-step selection process is summarized.

2026-05-11

This article introduces a method for testing the flexibility of elastic coatings using a cylindrical mandrel bend tester. During the test, a coated test panel is bent around cylindrical mandrels of different diameters to an angle of 180 degrees, and the coating is observed for cracking or peeling. The instrument is equipped with mandrels ranging from 1 to 5 mm, and the test panels must be prepared and dried according to specified procedures. Testing begins with the smallest mandrel, gradually increasing in size until coating failure occurs, with the smallest diameter the coating can withstand serving as the flexibility index. The results are influenced by the degree of coating drying, environmental temperature and humidity, substrate, and bending speed; operation under standard conditions is recommended. This method is suitable for elastic coatings such as acrylics and polyurethanes, and is used for quality control of protective coatings on steel structures and wooden components. During operation, gloves should be worn and the instrument kept clean.

2026-05-08

This article introduces how to quickly evaluate the scratch resistance of paint films using a pencil hardness tester. During the test, standard pencils (ranging from 6B to 9H) are drawn across the coating at a fixed angle and pressure to observe whether scratches occur. The article provides a detailed explanation of the operational steps, including sample preparation, pencil sharpening, scratch operation, and result interpretation. It also emphasizes factors that affect the results, such as the condition of the pencil tip, applied pressure, and coating thickness, as well as correction methods for common issues. Data recording must include sample information, test conditions, and the final hardness level. The entire method complies with standards such as ISO 15184 and ASTM D3363.

2026-05-08

This paper introduces the application of the Stormer viscometer in the control of latex paint can opening viscosity. Can opening viscosity affects application performance and user experience, with values that are either too high or too low potentially causing issues. By simulating brushing shear conditions, the Stormer viscometer measures Krebs Units (KU), helping to ensure product consistency. The measurement requires instrument calibration, control of temperature and humidity, and adherence to standard operational procedures. Viscosity is influenced by factors such as thickeners, solids content, particle size, and additives, and can be adjusted through formulation modifications and staged addition. Result data should be evaluated comprehensively in conjunction with other indicators like thixotropy, and the instrument requires regular calibration and maintenance.

2026-05-08

This article introduces how to evaluate the spray atomization effect of water-based paints using a rotational rheometer. It first explains the two stages of atomization and the importance of rheological parameters such as shear viscosity, storage modulus, loss modulus, and complex viscosity. Then, it describes the testing methods, including shear rate sweep and oscillatory frequency sweep. Next, it analyzes the optimal ranges of key parameters, such as the shear-thinning index, storage and loss moduli, and complex viscosity. Finally, using data from a typical paint sample, it demonstrates how these parameters correspond to atomization performance.

2026-05-08

This article introduces the application of the laboratory blade heating coater in hot melt adhesive coating. It first explains the coating process and principles, including the three stages of heat conduction, fluid shear, and surface wetting, as well as the effect of temperature on adhesive viscosity. Next, it discusses key parameters of the equipment, such as the heating temperature range, blade gap accuracy, coating speed, and substrate tension. Then, it briefly outlines the operation steps, from preheating to stable operation, and introduces evaluation indicators for coating quality, such as thickness uniformity and peel strength. Finally, it mentions solutions to common problems and the expanded applications of the equipment in coating other materials.

2026-05-07

This study examines how a printability tester simulates the impact of different pressures on ink transfer rate in offset printing. The experiment varied pressure from 50 to 400 N/cm² under fixed conditions, revealing that at lower pressures, the transfer rate was only 30% to 40%. As pressure increased to 200-300 N/cm², the transfer rate rose to 67% to 76%, but beyond 350 N/cm², the increase slowed or even slightly decreased. The paper also presents a logarithmic model to fit the relationship between pressure and transfer rate, and highlights operational details such as cleaning and sample consistency.

2026-05-06

This article introduces how the gravure printability tester is used for water-based ink proofing and pinhole defect evaluation. Water-based inks are environmentally friendly but prone to tiny pinhole defects. The instrument achieves standardized sample preparation by controlling parameters such as cell depth and blade angle, reducing human interference. Pinholes are related to the surface tension of the ink, with a low occurrence rate when the surface tension is below 40. Through sample observation and microscopic analysis, the defect coverage can be quantitatively evaluated, aiding in the optimization of ink formulations. However, this instrument cannot fully simulate high-speed multi-color printing and is suitable for laboratory screening use.

2026-05-06

This article introduces how a contact angle measuring instrument is used to study the relationship between wettability and substrate surface tension in ink printing. It first explains the principle, where the degree of wetting is determined based on the contact angle—an angle smaller than 90 degrees indicates good wetting. The measurement employs the sessile drop method, using standard test liquids to measure the contact angle and indirectly calculate the substrate's surface tension. Analysis shows that substrate surface tension must be higher than that of the ink for sufficient wetting, and common treatments such as corona discharge can enhance surface tension. The article also notes that temperature, humidity, cleanliness, and roughness can affect results, and summarizes how this method guides the optimization of the printing process.

2026-05-06

This paper introduces the application of fluorescence spectrophotometry in the spectral measurement of anti-counterfeiting fluorescent inks, including instrument calibration, sample preparation, and methods for measuring excitation and emission spectra. By fixing either the emission or excitation wavelength for scanning, peak wavelengths and intensities are obtained, and parameters such as full width at half maximum are extracted for quality analysis. The article also discusses correction methods for interferences such as Raman scattering and fluorescence quenching, as well as operational precautions such as avoiding photobleaching and controlling ambient temperature, providing a reproducible measurement procedure for laboratories.

2026-05-06

This article primarily discusses the use of a flexographic proofer to evaluate the color reproducibility of flexographic inks. It introduces the role of the proofer in simulating production conditions, as well as how to prepare samples by setting parameters such as pressure, speed, and anilox rolls. Color measurements are then taken using a spectrophotometer/densitometer to calculate indicators such as color difference, solid density, and dot gain, thereby assessing the accuracy of the ink color. The article also cites an example of water-based ink used for corrugated boxes, illustrating the color difference between the undiluted ink and the letdown ink. Finally, it emphasizes the importance of standardized operation and proper cleaning of the proofer to minimize color deviations in mass production.

2026-05-06

This article explores the use of a gravure proofing press to comprehensively evaluate the printability and drying performance of gravure inks. In the experiment, standard equipment was used to test the dot clarity, transfer rate, and leveling properties of different inks, while the drying time was recorded using the filter paper method and infrared temperature measurement. The results show that solvent-based inks have a higher transfer rate but dry slowly, whereas water-based inks exhibit the opposite trend. The study also proposes a weighted scoring method for ink selection and discusses the influence of parameters such as impression pressure and doctor blade angle.

2026-05-06

This article presents a method for testing ink color transfer using a rubbing fastness tester, simulating both dry and wet rubbing conditions. Dry rubbing involves rubbing the ink surface with dry white cotton cloth, while wet rubbing uses water-saturated white cotton cloth. The color difference of the white cotton cloth before and after rubbing is measured using a spectrophotometer, and the degree of color transfer is evaluated in combination with gray scale ratings. Test results show that black water-based ink exhibits greater transfer under wet rubbing conditions, while red UV-curable ink shows the smallest transfer. This method references international and national color fastness standards and can be used to evaluate the color stability of different inks in practical applications.

2026-05-06