Precision Coating

Precision coating is a high-precision industrial process that achieves precise control over the thickness and position of a coating by uniformly applying liquid or semi-solid materials to the surface of a substrate (such as glass, metal, or plastic), with accuracy down to the micrometer level. Currently, this technology is increasingly widely used in the automotive interior and exterior trim industry, for example, in the production of scratch-resistant coatings, anti-fingerprint treatments, optical decorative coatings, anti-reflective coatings, anti-fog coatings, heat-insulating films, sun-shading films, audio surface coatings, and functional films for ambient light sensors or head-up displays, effectively improving appearance quality and product performance.

Slot Die coating technology is a high-precision thin-film coating method applicable to various industries, including interior and exterior trim applications in the automotive industry. This technology effectively and uniformly coats materials onto a substrate and is widely used in the manufacture of precision, durable, and high-quality coatings.

• How Slot Die Coating Technology Works
  Slot Die technology distributes liquid coatings or solutions uniformly onto a substrate surface through a narrow slit (called a "slot"). Coating thickness and uniformity can be precisely controlled through slit design, material flow rate, and substrate velocity. This makes the technology particularly suitable for applications requiring high precision and stability.
• Features of Slot Die Technology
  • High-precision coating:It ensures uniform coating thickness, suitable for complex interior and exterior decoration needs.
  • Save materials:It has high material utilization efficiency, reduces waste, and is particularly suitable for large-scale production of automotive interior and exterior trim.
  • Suitable for a variety of substrates:It can be used on substrates such as plastics, metals, and glass.
  • High stability:Suitable for automated production lines, improving production efficiency.
• Applications in the automotive industry
  In automotive interior and exterior trim, Slot Die technology is used to produce various high-performance films and coatings, enhancing the appearance, functionality, and durability of products. Here are some specific applications:
  Interior decoration application
  • Decorative films and coatings:
    Apply a single-color coating (such as a color coating or protective layer) to the decorative film for use on interior parts such as dashboards and door panels.
    Scratch-resistant coating enhances the durability of interior surfaces.
  • Functional coatings:
    Anti-fingerprint coatings are applied to touchscreens or center consoles.
    A matte finish is used to enhance the premium feel of interior surfaces.
  • Sound-absorbing and vibration-damping materials:
    Coatings applied to internal sound-absorbing pads or damping membranes improve in-vehicle comfort.
  Exterior decoration application
  • Car body protective film:A highly transparent protective film coating is applied to prevent scratches and UV damage.
  • Coated glass:UV-resistant or anti-glare coatings for car windows and sunroofs.
  • Surface treatment:Waterproof and anti-fog coatings are applied to the housings of automotive lights.
  • Headlight emblems and trim:Metallic or mirror-like thin-film coatings are used for logos and decorative strips.

The application of Slot Die technology in automotive interior and exterior trim not only enhances the appearance and performance of products, but also meets the modern automotive industry's demands for environmental protection and efficient production.

Micro Gravure coating is a high-precision contact coating technology that uses finely etched gravure rollers to uniformly transfer the coating liquid onto the substrate. It is suitable for low-viscosity coatings and precision thin film coating processes.

• Working principle
  • Coating solution supply:The coating solution is stored in the coating tank and supplied to the surface of the Micro Gravure roller.
  • Roller transfer:As the gravure roller rotates, the cells carry the coating liquid and transfer it onto the substrate.
  • Metering control:The amount of coating is controlled by a metering roller or a doctor blade to ensure uniformity.
  • Coating formation:The substrate receives the coating liquid as it moves, forming a precision coating.
  • Drying and curing:The coating is dried to complete the final coating process.
• Features
  • Ultra-thin uniform coating:The coating thickness can be controlled between 1 and 10 micrometers (μm).
  • Suitable for low-viscosity coating liquids:Suitable for liquid coating materials with a density of less than 100 centipoise (cP).
  • High precision and stability:Uniform coating is achieved through gravure design.
  • Wide applicability:It can be used on substrates such as PET, PI, metal foil, and glass.

Precision coating technology is widely used in tapes and adhesives, electronic products, building materials, medical testing, printing industry and other fields to improve the functionality and process stability of materials. Common applications include:

• Electronic materials:Conductive layers for displays, transparent conductive films for touch panels, electronic paper, and printed electronic conductive inks.
• New energy:Lithium battery electrodes and separators, solar cell light-absorbing layers.
• Optical thin films:Anti-reflective and fingerprint-resistant coatings, LCD screens, and optical functional films.
• Medical Technology:Drug patches, microneedle delivery layers, biosensor membranes, screening strips, and antibacterial coatings for medical devices.
• Industrial and building materials:Self-cleaning glass, heat-insulating window film, fire retardant, antistatic and scratch-resistant protective layer, roofing materials.
• Printing and Special Applications:Plastic film, OLED coating, circuit board, functional film for food packaging.

This technology is suitable for high-precision and thin-film processes, ensuring uniform coating and imparting special functions to materials, and its application areas continue to expand.

The precision of precision coating is determined by several factors, including the viscosity and temperature of the coating liquid, the speed and pressure of the coating equipment, and the surface condition of the substrate. By precisely controlling these conditions and using high-quality coating equipment, the uniformity and stability of the coating can be effectively improved.

To achieve high-precision coating, optimization is needed in aspects such as equipment adjustment, material properties, and process parameters. The key aspects include:

• Precision coating equipment
  • High-precision coating wheel:Use a finely etched gravure roller or metering roller to ensure uniform transfer.
  • Stabilizing coating mechanism:Precise control of roller pressure, substrate tension, and running speed reduces uneven coating.
• Material control
  • Coating viscosity and rheological properties:Maintain appropriate viscosity (e.g., 1~100 cP) to avoid sagging or uneven thickness.
  • The coating is evenly dispersed:Liquid stability is ensured through stirring, filtering, and defoaming.
• Process control
  • Coating speed and pressure adjustment:Uniform transfer is ensured through linear speed ratio and contact pressure.
  • Environmental condition control:Temperature, humidity, and dust-free environment can affect coating stability, and appropriate conditions must be maintained.
  • Drying and curing technology:Use hot air, ultraviolet (UV) light, or infrared light to dry the coating to avoid uneven coating.
• Detection and feedback mechanism
  • Real-time thickness gauge:Monitor coating thickness to ensure accuracy of 1 to 10 micrometers (μm).
  • Optical and Laser Scanning:Inspect coating uniformity and defects.
  • Closed-loop control system:Through sensing and data analysis, coating parameters are automatically adjusted to maintain stable quality.

Precision coating requires highly stable and precise equipment to ensure coating uniformity and quality. Key equipment and critical elements include:

• Coating equipment
  • Coating machine:This includes gravure coaters, micro gravure coaters, slot dies, doctor blade coaters, and roller coaters, with the appropriate model selected based on different process requirements.
  • Speed control system:Ensure stable substrate delivery, precisely adjust coating rate, and reduce coating thickness variation.
• Materials and Environmental Control
  • Consumables (coating liquid):Ensure the viscosity, dispersion uniformity, and stability of the coating to avoid sagging or uneven coating.
  • Cleanroom:Maintaining appropriate temperature, humidity, and a dust-free environment reduces the impact of pollution and improves coating quality.
• Drying and curing system
  • Oven:By using methods such as hot air drying, ultraviolet (UV) curing, and infrared heating, we ensure that the coating forms a uniform film and improves adhesion.
• Auxiliary and testing equipment
  • Paint supply system:It includes stirring, filtering, and defoaming devices to ensure uniform distribution and stability of the coating.
  • Substrate delivery and tension control:By using guide rollers and tension control, substrate wrinkling and misalignment are avoided, thus improving coating stability.
  • Detection and feedback system:Real-time thickness gauges, optical scanning, and laser inspection are used to ensure coating accuracy, and parameters are adjusted in real time through a closed-loop control system.

These devices and control mechanisms can effectively improve the stability and quality of precision coating, ensuring that the process meets high precision requirements!

Precision coating requires maintaining stable temperature, humidity, and cleanliness to ensure liquid flow and coating uniformity, and to avoid contamination that could affect quality.

• Cleanliness control
  • Clean, dust-free environments (Class 1000 or higher) reduce airborne dust and contaminants.
  • Operators should wear dustproof clothing, gloves, and masks to reduce the ingress of foreign objects.
• Temperature and humidity control
  • temperature:At 20-25°C, the viscosity and flowability of the coating are stabilized, avoiding the impact of temperature changes on the coating effect.
  • humidity:40-60% RH to prevent static electricity and excessive solvent evaporation, ensuring coating uniformity.
• Airflow and pressure management
  • The laminar flow system ensures stable airflow and reduces the impact of dust.
  • Positive pressure environment prevents external contaminants from entering the coating area.
• Solvent and Volatile Product Management
  • Good ventilation is essential; use fume hoods or activated carbon filters.
  • Waste gas and waste liquid are treated in accordance with environmental protection standards to avoid environmental pollution.
• Electrostatic protection
  • Antistatic flooring and workbenches reduce electrostatic interference.
  • Operators should wear anti-static wrist straps and ankle straps to reduce the risk of static electricity buildup.
• Equipment stability and maintenance
  • High-precision flow and pressure control ensures uniform coating.
  • Regularly maintain and calibrate the equipment to avoid mechanical errors affecting coating quality.
• Pollution prevention and quality control
  • High-efficiency filtration systems (such as HEPA filters) reduce particulate contamination.
  • Real-time monitoring and statistical process control (SPC) ensure consistent quality.

Even minor contamination or environmental changes can affect product functionality and quality. Therefore, strict environmental control and process management are crucial for ensuring high yield and stability during precision coating.

Precision coating, in-mold decoration (IMD), and out-of-mold decoration (OMD) are technologies related to the surface treatment and decoration of plastic or metal parts. These three are closely related, and a brief explanation and correlation are provided below:

• Precision Coating:This is a technique for precisely applying coatings to the surface of a substrate. It is typically used to create specific looks or functions, such as protection, color, or pattern. Precision coating technology can be used independently or in in-mold or out-of-mold decoration processes. In particular, precision coating can apply protective layers, special functional layers, such as scratch-resistant protective layers, optical layers, and pressure-sensitive adhesive layers, onto decorative films to protect the underlying decorative patterns from wear or to provide additional functions, such as anti-reflective properties or improved tactile feel.
• In-Mold Decoration (IMD):This technology involves placing decorative materials (such as printed patterns or films) inside a mold during the injection molding process, and then injecting plastic into the mold, allowing the decorative material to bond with the substrate. The advantage of IMD (Injection Molding) is that it allows for decoration and molding in a single step, increasing the wear resistance and durability of the parts.
• Out-of-Mold Decoration (OMD):Unlike IMD, OMD is a finishing process performed after the part has been molded. This can include painting, lamination, or other surface treatment techniques. OMD offers greater flexibility and is suitable for products that require post-production modifications or diverse finishing options.
• The relationship between the three
  • Application scenarios:Precision coating technology can be used in conjunction with IMD and OMD to enhance the appearance and performance of parts. Manufacturers can choose the most suitable finishing technique based on the product's requirements.
  • Quality and efficiency:IMD typically offers greater durability and texture, while OMD provides greater design flexibility. The choice of technology will affect production efficiency and product quality.
  • Market demand:As consumers demand higher standards for product appearance and functionality, the application of these technologies is becoming increasingly widespread, especially in fields such as electronics, automobiles, and home appliances.

Precision coating and printing are closely related in the manufacturing and processing fields. Although their technical principles are different, they can be used in combination or complement each other in many applications.

Main functions and applications

• Precision Coating
  • It is mainly used for uniformly coating functional materials, such as protective layers, optical films, adhesive layers, etc., to improve product durability and properties (scratch resistance, fingerprint resistance, anti-reflective properties, conductivity, etc.).
  • It is widely used in electronic displays, optical films, medical coatings and other fields.
  • In the printing industry, precision coating can be used to coat printing inks or printing materials and solve problems such as ink drying and substrate ink absorption.
• Printing
  • It is mainly used to create visual patterns, logos, or electronic circuits.
  • It is used in packaging, in-mold decoration (IMD), out-of-mold decoration (OMD), and printed circuit boards (PCB).

The connection between the two

• Coating enhances printing results:It can evenly coat printing ink, improve adhesion and quick drying, and optimize the surface properties of the substrate.
• Protect the printed pattern:In IMD and OMD applications, a scratch-resistant and UV-resistant coating is applied to enhance durability.
• Precision coating combined with printing technology:In the electronics industry, conductive coatings can be combined with inkjet printing and screen printing to manufacture precision circuits or sensors.

Main differences

• Precision coating is primarily used for the uniform application of functional materials, such as protective layers, adhesive layers, and conductive layers, to enhance product durability and specific properties. It is commonly found in applications such as touch panels, optical films, and medical coatings. Technologies include spin coating, spray coating, and slot die coating.
• Printing is used to create visual patterns, logos, or electronic circuits, and is applied to packaging, in-mold decoration (IMD), out-of-mold decoration (OMD), and printed circuit boards (PCBs). Common techniques include screen printing, inkjet printing, and gravure printing.

in conclusion
Precision coating and printing are complementary technologies. Printing is responsible for creating visual and functional patterns, while coating provides additional protection and performance enhancement. Although the two technologies differ, they are inseparable in many industrial applications. For example, coating technology can improve the adhesion and drying effect of printing inks, or provide scratch-resistant and UV-resistant layers to protect printed patterns. This combined application is widely used in fields such as electronic displays, packaging decoration, printed circuits, and optical films, helping to improve manufacturing efficiency and product quality.

Precision coating technology offers key advantages in many industries, enhancing product performance, manufacturing efficiency, and quality. Its main advantages are as follows:

• High uniformity and precise control
  • The coating thickness can reach the nanometer or micrometer level, ensuring uniformity and meeting high precision requirements.
  • Suitable for applications such as optical films, electronic displays, medical coatings, and sensors.
• Suitable for mass production, effectively saving materials
  • Roll-to-Roll coating technology enables large-scale automated production and increases capacity.
  • Compared to traditional spraying or dip coating, it can reduce material waste, lower production costs, and meet environmental protection requirements.
• Adaptable to a variety of different liquid materials and substrates
  • It can be coated with a variety of liquid materials, including water-based, solvent-based, and UV-curable materials.
  • It is suitable for a wide range of materials, including glass, plastic, metal, and flexible substrates (PET, PI).
• Provides versatility and protection
  • It can be coated with functional layers such as anti-scratch, anti-fingerprint (AF), waterproof, UV-resistant, anti-reflective (AR), and conductive layers to improve product durability and performance.
  • It can be applied to the surface coating of decorative films, such as patterned films, colored films, and metallic films, to protect the decorative layer from wear and enhance the visual and tactile quality.
  • It is widely used in touch panels, optical films, sensors, medical devices, IMD/OMD decorative films and other fields.
• It can be integrated with other processes to improve manufacturing efficiency.
  • It can be combined with printing, coating, laser etching and other technologies to improve manufacturing efficiency.
  • Suitable for large-area continuous coating (Roll-to-Roll) and batch production (Batch Coating), meeting high capacity requirements.

in conclusion
Precision coating technology, with its core advantages of high precision, high uniformity, and multifunctionality, can improve product quality, reduce production costs, and meet the requirements of environmental protection and efficient manufacturing. It is widely used in optoelectronics, electronics, medical, and industrial manufacturing fields.

The coating thickness and film width of precision coating vary depending on application requirements, equipment technology, and material properties. Below is a comparison of common technical ranges and our company's actual production capabilities:

• Typical coating thickness range
  • Ultra-thin coating (nanoscale):Approximately 10 nm to 500 nm, such as anti-reflective layers, OLED interface layers, and conductive coatings.
  • Thin film coating (micron level):Approximately 0.5 µm to 50 µm, commonly found in optical films, protective films, and medical coatings.
  • Thick film coating (millimeter level):Approximately 50 µm to 1 mm, it is used in UV-curable adhesive layers, glue coatings, etc.
• Typical Coating Width
  • Small area coating (precision electronic components):Approximately 10 mm to 300 mm, such as sensors, PCBs, and medical devices.
  • Medium-sized coating:Approximately 300 mm to 1000 mm, suitable for optical films, touch panels, etc.
  • Large-area coating:Approximately 1000 mm to 3000 mm or wider, used in displays, solar cells, industrial packaging films, etc.
• Our company's actual coating specifications range
  Depending on the coating technology, our equipment provides the following stable and adjustable coating conditions:
  • Microgravure (MG) coating
    Coating thickness:Approximately 1~15 µm
    Membrane width range:Approximately 500 ~ 700mm
• Slot Die Coating
  Coating thickness:Approximately 30 ~ 70 µm
  Membrane width range:Approximately 500 ~ 700mm
• Factors affecting coating thickness and film width
  • Coating technology:Different techniques, such as slot die coating, doctor blade coating, and spin coating, have a direct impact on thickness control and uniformity.
  • Material properties:Factors such as solution viscosity, surface tension, and solid content can affect the quality and stability of the film.
  • Process parameters:For example, roller speed, flow control, and substrate speed all directly affect the final coating effect.

in conclusion
The thickness and width of precision coatings are extremely diverse and can be fine-tuned and optimized according to different product applications. From ultra-thin optical coatings to thick adhesive layers, from small-sized precision components to large-area industrial substrates, our company has stable and high-precision coating capabilities, which can flexibly meet the needs of various industries.

The types of substrates used in precision coating are diverse, and their selection is mainly determined by the functional requirements of the product and the process conditions, including heat resistance, surface properties, conductivity, and dimensional stability. The following are common substrate types and their applications:

• Plastic films
  Common materials include:PET (polyester), PC (polycarbonate), PI (polyimide), etc.
  • application:Optical films, protective films, touch panels, electronic film materials, etc.
  • Features:It has excellent flexibility, high transparency, and can withstand medium and high temperatures, making it suitable for high-speed continuous coating.
• Metal Foils & Thermal Materials
  For example:Copper foil, aluminum foil, conductive cloth, graphite heat sink, etc.
  • application:Battery structure, EMI shielding, thermal conductive module, electronic heat dissipation materials
  • Features:It has excellent electrical and thermal conductivity, stable structure, and is suitable for functional coatings (such as adhesive layers and protective layers).
• Glass
  For example:Flat glass, ultra-thin glass, tempered glass
  • application:Optical components, sensors, AR/VR displays, panels
  • Features:High flatness and transparency, suitable for ultra-thin, high-precision coatings
• Other materials
  For example:Non-woven fabrics, ceramic substrates, paper materials, etc.
  • application:Filter media, medical coatings, special electronic substrates
  • Features:Choose based on application requirements, either with good absorbency or a special structure.
• Substrate selection considerations
  • Functional requirements:Such as electrical conductivity, heat dissipation, optics, and gas barrier properties.
  • Process conditions:Includes coating speed, drying temperature, tension control, etc.
  • Mechanical and thermal properties:Such as flexibility, dimensional stability, and temperature resistance range.
  • Surface treatment fit:Is surface modification, such as corona treatment or plasma treatment, required?