How to clean polyester hot melt yarn to maintain its optimal performance?

How to clean polyester hot melt yarn to maintain its optimal performance?

1. Preparation before cleaning polyester hot melt yarn
1.1 Check the fiber state
Before cleaning polyester hot melt yarn, its fiber state must be fully checked, which is a key step to ensure the cleaning effect and maintain the fiber performance. The inspection content includes the appearance, physical properties and chemical stability of the fiber.
Appearance inspection: Carefully observe whether there are obvious stains, oil stains, dust or other contaminants on the fiber surface. These contaminants may affect the performance and service life of the fiber. At the same time, check whether the fiber has physical damage such as wear, breakage or deformation. For example, wear on the fiber surface may cause its strength to decrease, while breakage may affect its overall structural integrity.
Physical property inspection: Evaluate the strength and flexibility of the fiber through tensile testing, bending testing and other methods. Polyester hot melt yarn usually has high tensile strength and good flexibility, but if the fiber is affected by external forces or environmental factors during use, its physical properties may change. For example, long-term exposure to high temperature or humid environment may cause the fiber strength to decrease. According to the test results, it can be judged whether the fiber needs to be cleaned or repaired.
Chemical stability check: Understand whether the chemical substances, such as detergents, solvents, etc., that the fiber is exposed to will corrode or react chemically to the fiber. Polyester hot melt yarn has good chemical stability, but in some special environments, such as strong acids, strong alkalis or organic solvents, the chemical structure of the fiber may be destroyed. Therefore, it is necessary to confirm the chemical stability of the fiber before cleaning, and select appropriate detergents and cleaning methods to avoid damage to the fiber.

2. Selection of cleaning methods

2.1 Physical cleaning methods

Physical cleaning methods mainly remove pollutants on the surface of polyester hot melt yarn by mechanical action. This method will not affect the chemical structure of the fiber and is suitable for most cases.

Brushing method: Use a soft brush to gently brush the fiber surface to effectively remove dust and loose stains. This method is simple to operate and low in cost, but the cleaning effect on stubborn stains is limited. For example, when cleaning the uppers made of polyester hot melt yarn, the brushing method can remove most of the dust, but it is not effective for stubborn stains such as oil stains.

Scrubbing method: Dip a dust-free cloth or soft towel in an appropriate amount of clean water or neutral detergent and gently wipe the fiber surface. This method can clean the fiber more carefully and is suitable for occasions with high requirements for surface cleaning. For example, when cleaning non-woven fabrics produced by mixing polyester hot melt yarn and conventional polyester, the scrubbing method can effectively remove stains on the fiber surface while avoiding damage to the fiber.
Ultrasonic cleaning method: Use the cavitation effect of ultrasonic waves in liquid to generate strong shock waves to remove stains from the fiber surface. This method has a good cleaning effect and can remove stubborn stains deep into the fiber, but the equipment cost is high. For example, when cleaning spinning components, ultrasonic cleaning can effectively remove polyester residues on the surface and inside of the component, with a short cleaning time and little damage to the component.
2.2 Chemical cleaning method
The chemical cleaning method achieves the purpose of cleaning by using chemical reagents to react chemically with pollutants. This method has a good cleaning effect on stubborn stains, but chemical reagents need to be carefully selected to avoid damage to the fiber.
Water washing method: Most soluble stains and dust can be removed by washing the fiber with clean water. This method is simple and easy, and has low cost, but it has poor cleaning effect on insoluble stains such as oil stains. For example, when cleaning curtain screens made of polyester hot melt yarn, water washing can remove dust and some stains on the fiber surface, but other cleaning methods are required for stubborn stains such as oil stains.
Alkaline washing method: Using alkaline solution (such as sodium hydroxide solution) to wash the fiber can remove organic stains such as oil stains and grease. This method has good cleaning effect, but the concentration and temperature of the alkali solution need to be controlled to avoid corrosion to the fiber. For example, when cleaning the melt filter element, the alkali washing method can effectively remove grease and stains on the surface and inside of the filter element, but it needs to be rinsed with clean water in time after cleaning to remove residual alkali solution.
Acid washing method: Using acidic solution (such as hydrochloric acid solution) to wash the fiber can remove inorganic stains such as metal ions. This method is suitable for removing stains such as rust and scale on the fiber surface, but it is also necessary to control the concentration and temperature of the acid solution to prevent the fiber from being corroded. For example, when cleaning the spinneret, the acid washing method can remove rust and scale on the surface of the spinneret and increase the service life of the spinneret.

3. Precautions during cleaning

3.1 Temperature control
When cleaning polyester hot melt yarn, temperature control is crucial, which is directly related to the performance and cleaning effect of the fiber.

Effect of temperature on fiber properties: Polyester hot melt yarn has a certain heat resistance, but too high a temperature may cause the physical properties of the fiber to deteriorate. For example, when the temperature exceeds the melting point of the fiber (usually between 160℃ and 260℃), the fiber may melt or deform, thereby affecting its strength and flexibility. Therefore, during the cleaning process, high-temperature water or high-temperature steam should be avoided from directly contacting the fiber. It is recommended to control the water temperature between 40℃ and 60℃, which can ensure the cleaning effect without damaging the fiber.
Effect of temperature on cleaning effect: Appropriate temperature can improve the activity of detergents and enhance their ability to remove stains. For example, when using neutral detergent for water washing, controlling the water temperature at around 40°C can better dissolve components such as grease and protein in the stains, thereby improving the cleaning effect. However, if the temperature is too high, the active ingredients in the detergent may decompose or become ineffective, which will reduce the cleaning effect. Therefore, during the cleaning process, it is necessary to reasonably control the temperature according to the specific conditions of the detergent and fiber used to achieve the best cleaning effect.
3.2 Friction force
When cleaning polyester hot melt yarn, the control of friction force is also very critical. It not only affects the cleaning effect, but may also cause damage to the fiber.
Effect of friction force on fiber damage: Although polyester hot melt yarn has high strength and wear resistance, if the friction force is too large during the cleaning process, it may still cause wear or breakage of the fiber surface. For example, when using the brushing method for cleaning, if too much force is applied, the fiber surface may be scratched, affecting its appearance and performance. Therefore, during the cleaning process, appropriate cleaning tools, such as soft brushes or dust-free cloths, should be selected, and the friction strength should be controlled to avoid unnecessary damage to the fibers.
The effect of friction strength on cleaning effect: Appropriate friction strength can effectively remove stains on the fiber surface, but too little friction strength may not achieve the desired cleaning effect. For example, in the scrubbing method, if the friction strength is insufficient, stubborn stains on the fiber surface may not be completely removed. Therefore, during the cleaning process, it is necessary to reasonably adjust the friction strength according to the nature of the stains and the state of the fiber, so as to ensure the cleaning effect and avoid damage to the fiber.

4. Post-cleaning treatment
4.1 Drying method
The drying method of polyester hot melt yarn after cleaning has an important impact on its performance and subsequent use. Choosing a suitable drying method can ensure that the fiber remains in good condition after cleaning.
Natural drying: Natural drying is a simple and low-cost drying method. Place the cleaned polyester hot melt yarn in a well-ventilated environment and let it dry naturally. This method will not cause additional thermal damage to the fiber and is suitable for situations where the drying speed is not required. However, natural drying takes a long time, and in a humid environment, it may cause bacteria to grow on the fiber surface or produce odor.
Hot air drying: Hot air drying accelerates the evaporation of moisture on the fiber surface by blowing hot air, and the drying speed is faster. Usually, the hot air temperature is controlled between 60℃ and 80℃, which can ensure the drying efficiency without negatively affecting the hot melt properties of the fiber. For example, in industrial production, hot air drying is often used for batch drying of polyester hot melt yarn, which can complete the drying process in a shorter time and improve production efficiency. However, it should be noted that hot air drying equipment needs regular maintenance to ensure the stability of air volume and temperature.
Dryer drying: Using a dryer to dry polyester hot melt yarn is also a common method. The dryer can control the drying process by setting the appropriate temperature and time to ensure that the fiber is evenly dried. Generally speaking, the drying temperature should be lower than the melting point of the fiber, and it is recommended to control it below 120℃. For example, in some small processing enterprises, dryer drying is widely used in the cleaning post-processing of polyester hot melt yarn, which can quickly remove moisture and reduce the time the fiber is damp. However, drying in a dryer may have a certain effect on the softness of the fiber, so appropriate softening treatment may be required after drying.
4.2 Performance testing
The cleaned and dried polyester hot melt yarn needs to be tested for performance to ensure that its performance meets the use requirements and avoid performance degradation caused by the cleaning process that affects subsequent applications.
Physical performance testing:
Tensile strength test: The fiber is tensile tested by a tensile testing machine to measure its breaking strength and elongation. The cleaned polyester hot melt yarn should maintain a high tensile strength, generally not less than 90% of the original fiber strength. For example, for polyester hot melt yarn used for automotive lining, its tensile strength should still meet the strength requirements of automotive interior after cleaning to ensure the safety and durability of the product.
Flexibility test: The bending test method is used to evaluate the flexibility of the fiber. The cleaned fiber should have good flexibility and be able to withstand certain bending and folding under normal use conditions. For example, when making sofa fabrics, polyester hot melt yarn needs to maintain good flexibility to adapt to the frequent use and shape changes of the sofa.
Chemical performance testing:
Chemical stability test: Place the fiber in a specific chemical environment, such as weak acid, weak alkali or organic solvent, and observe whether it undergoes chemical reactions or performance changes. Polyester hot melt yarn should maintain good chemical stability after cleaning, and will not be chemically corroded by residual detergents or environmental factors. For example, when used for curtains and window screens, the fiber needs to be able to resist the erosion of daily detergents and chemicals in the environment.
Heat resistance test: The fiber is tested for heat resistance by high-temperature ovens and other equipment to measure its performance changes under high temperature conditions. After cleaning, the polyester hot melt yarn should maintain its original heat resistance and the melting point should not drop significantly. For example, when used for fabrics in high-temperature environments, the heat resistance of the fiber is a key factor in ensuring product performance.
Appearance inspection: Carefully check the appearance of the fiber to ensure that there are no residual stains, damage or deformation on its surface. Fibers with good appearance can not only meet the aesthetic requirements of the product, but also indicate that its internal structure has not been seriously damaged. For example, when producing high-end suit linings, the appearance quality of the fiber directly affects the quality and market competitiveness of the product.

5. Summary
As an important functional fiber, polyester hot melt yarn is widely used in many fields. Its cleaning process is crucial to maintain fiber performance and extend its service life. By comprehensively checking the fiber state, including appearance, physical properties and chemical stability, it can provide an important basis for subsequent cleaning work. In terms of the selection of cleaning methods, physical cleaning methods such as brushing, scrubbing and ultrasonic cleaning have their own advantages and are suitable for different situations; chemical cleaning methods such as water washing, alkali washing and acid washing are aimed at different types of stains, but chemical reagents should be selected with caution. In the cleaning process, the control of temperature and friction force is extremely critical. Excessive temperature or excessive friction may damage the fiber and affect its performance. The drying method and performance testing after cleaning should not be ignored. Reasonable drying methods such as natural drying, hot air drying and dryer drying can ensure that the fiber is in good condition, and comprehensive performance testing can verify whether the cleaned fiber still meets the use requirements.
In summary, the cleaning of polyester hot melt yarn is a systematic process that requires comprehensive consideration of multiple aspects such as fiber state, cleaning method, process control and subsequent treatment to ensure that it can maintain optimal performance after cleaning and meet the needs of different application scenarios.