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A high power COB UV LED Module could be listed on a specification sheet to have a tremendous amount of radiant output, but not work well when put into a small curing machine. Thermal resistance, electrical driving conditions and the method of delivery of the emitted light to the working surface are the differences often. When it comes to picking a COB module, it's not just about the highest wattage for UV equipment manufacturers. The module should function successfully in the total optical, electrical and thermal system. Knowing these needs in the beginning can help avoid costly re-design when equipment is being developed. What is COB UV LED Module? Chip-on-Board (COB) is the acronym for COB. In this packaging technology, a plurality of LED chips are attached to the same substrate to form a compact high density light source. A COB module is different from the arrangement with numerous individually-packaged LEDs by having all the emitting chips packed into a single assembly. Such architecture can enable small size of equipment and ease in mechanical integration. But with high chip density, the construction and thermal design of the substrate becomes even more critical. UVET provides various COB UV LED modules for manufacturers ...

It is possible to have a UV LED Printing System with high irradiance, but with variable curing results. It's because much more than the light source is required for successful ink curing. The UV energy reaching printed surfaces depends on the speed of the printing machine, the chemistry of the ink, the width of the irradiation device, the working distance and the cooling performance. The greatest hurdle for printing equipment manufacturer and production engineer is choosing a system that is appropriate for the printing process and will have repeatable curing under continuous operating conditions. So the first step in selecting the right evaluation is to consider printing needs and not just the top rated UV lamp. UV LED Printing System is What? UV LED Printing System is a system that is designed to utilize UV LED to trigger the photopolymerization of compatible UV-curable inks and coatings. The liquid formulation undergoes a chemical reaction with the exposure to become the cured film. Compared to traditional mercury UV lamps, LEDs produce light in a much more constrained wavelength band and can be switched rapidly and controlled irradiation. A typical industrial system consists of a UV LED curing head, driver/controller, cooling units and ...

Two UV LED curing lights may be advertised as having the same intensity, but give different curing results on the same work piece. The difference usually lies in the different irradiations coverages, working distances, wavelength compatibility and light distribution over the material. Thus, in the case of industrial buyers, the choice of UV LED curing light is more than just wattage or choosing the most powerful light source. The starting point is the material to be cured, geometry of the workpiece and the production conditions in which the light will be used. So, What is a UV LED Curing Light? A UV LED curing light is one used to start the polymerisation process in compatible adhesives, coatings, inks and resins using ultraviolet or near-ultraviolet radiation. The photoinitiators contained in these materials are capable of capturing appropriate wavelengths and initiating a chemical reaction which results in a cured network. In contrast to the traditional mercury UV lamps, UV LED technology has the advantages of rapid switching, controlled irradiation, and low infrared emission. Curing however relies on the emitted wavelength being able to match the material formulation. Industrial applications include electronic assembly, optical bonding, manufacturing of medical devices and some printing processes. ...

UV cured PCB coating can look like it has cured when it hasn't cured sufficiently next to tall components or the edges of the board. Light exposure can also be uneven in electronic adhesives and protective encapsulants, causing similar issues. UV LED curing is consequently more than just a faster alternative to traditional curing methods, to the electronics manufacturer. The process should provide adequate exposure without impacting sensitive components or slowing down production. The first step to successful implementation is to understand which materials need to be cured, how the light gets to them, and what the finished assembly will be judged on. What are the Applications of UV LED in Electronics Industry? UV LED curing is a process that employs specific UV wavelengths to promote the cure of compatible adhesives, coatings and encapsulants. Applications in electronics are bonding of components, protective coatings, assembly of sensors, bonding and selected encapsulation processes of displays. The amount of exposure required for each application is different. Taking pictures of populated boards that require wide lighting is common with PCB coatings. Concentrated light is necessary for small adhesive bonds and careful attention to alignment and material properties is needed for optical assemblies. The UVET ...

A bond can appear to be completely cured, yet have an underexposed adhesive area. Especially near tubing joints, connectors and catheter hubs, curved surfaces and overlapping components may prevent UV light from penetrating. UV curing of catheters isn't just about saving time on adhesive curing for medical devices manufacturers. The process should consistently achieve good bonding and not harm sensitive polymer parts. That needs to be carefully controlled by taking into account adhesive compatibility, light distribution, exposure conditions and production validation. Catheter UV Curing – What is it? Catheter UV curing is a photochemical coating technique that is used to cure compatible UV curable adhesives in the medical area when assembling medical catheters. There are many applications for UV-curable adhesives such as joining catheter tubing to hubs, connectors, and other parts of the device. Exposing to the proper UV / near-UV LED light will trigger the polymerization process, as a result of which a bonding is formed. UV LED curing offers an advantage over some heat curing processes in that it is possible to expose in a localized manner and control the curing time with high precision. But, if the joint is to be properly cured, more than illumination is ...

The selection of the wavelength of the UV LED is not the choice of the highest intensity, nor the general rule of one wavelength curing deeper than another. To cure reliably, the first step is to focus on the spectral response of the adhesive, ink or coating. Wavelength-specific curing synchronizes the UV source and the photoinitiator, the substrate's transmittance, the thickness of the coating and the production speed. The UV LED Curing Light Bar comes in 4 different wavelengths: 365 nm, 385 nm, 395 nm and 405 nm, enabling engineers to choose a fixed wavelength for the process. Start by using the Photoinitiator. The photoinitiator absorbs the UV energy at a specific range and initiates the polymerization process. If the wavelength chosen for the selected LED light is outside of the range, longer exposure times may not yield a satisfactory cure. Ask the supplier of the adhesive, coating or ink for its absorption data and recommended UV spectrum. The datasheet is a starting point, and not the final production setting, as the response might change with the use of different amounts of pigment and/or filler, or different thickness of application. The absorption range can be wider for a material with multiple ...

The cure for medical assembly needs to go past simply being an initial glimpse of a bond that seems dry or is more at the surface. It should always provide sufficient adhesion and not compromise the transparency of plastic materials, flexibility of tubes and sensors or any other sensitive parts. To ensure the success of the curing process, the medical device manufacturer must have a defined window of curing between the adhesive, component material, joint geometry, UV wavelength and exposure conditions. A small UV LED curing unit can aid this process, but the settings of the equipment need to be tested for this particular assembly, not taken from a generic curing guide. Establish the Bond's Role and Hazard Risk. Start by figuring out what the bonded joint will have to do once it is incorporated into the final product. The mechanical and environmental conditions are different for each of the components of a housing seal, catheter connection, diagnostic cartridge, sensor window and wearable enclosure. Record bonded materials, joint dimensions, adhesive location, anticipated loads or exposure to moisture, chemicals or temperature changes. Also identify if the joint is cosmetic, structural, or fluid sealing and/or optically critical. These requirements define the meaningful ...

Unlike whole manufactured products, the exposure of small adhesive joints to UV light is not often necessary. The broad illumination can illuminate surrounding plastics, coatings, sensors or finished surfaces that are not to be cured. The energy is focused by a beam of UV light on the desired bond area. It is effective for microelectronic assembly and optical alignment, medical component bonding, prototyping and localized repairs. But, it will still be reliable when spot size, distance, angle and exposure time are controlled. The UV LED Curing Pen is capable of interchangeable spot sizes of 4-15 mm for manual curing in a specific area. Start with the Adhesive Joint. The size of the required beam should not be based on the total size of the component but on the adhesive joint. Take the diameter of the bond-line, adhesive volume, depth of the joint and surrounding materials. A controlled exposure might be needed for several exposures in a long seam or for a small circular adhesive deposit. If the area is much larger than the joint, the UV energy can possibly impact on sensitive nearby components. It is too small, some portions of the adhesive may not cure. Also determine if the adhesive ...

It is not possible to reliably achieve a wider curing area with a number of lamps side by side without testing the combined output of the lamps. The system can generate a single, uniform curing zone or a series of distinct energy bands which are visible, depending on module spacing, optical overlap, cooling and control timing. A modular area UV system should enable to increase the curing width without any change in the adhesion and surface finish of the printed image for the printer manufacturers and system integrators. It is important that the system be designed as a single curing platform rather than a number of individual UV lamps. Begin on the Required Curing Width. The first step is to define useful print width, rather than just physical width of the printer. Record the width of the largest image, the printhead layout, the position of the UV source and the distance between the UV source and the substrate. For inkjet application the UV LED system UVET is available with an irradiation area of 150 × 40 mm. The small size allows for curing around the print area without having to install a much bigger lamp than necessary for the application. If more than ...

It's not as easy as just putting a PCB under the brightest UV source to cure the electronics substrate. The process must produce the proper wavelength and UV energy without overheating the substrate or causing unneeded stress around sensitive components, or leaving material uncured in shaded areas. The goal is to create a reproducible curing window for the process engineer that correlates the photosensitive material, the substrate configuration, the UV processing equipment and the rate of production. Therefore, the quality and consistency of the final electronic assembly should be used as an evaluation criterion for a well-designed industrial UV LED curing system, instead of the irradiance output. Start with the Substrate and Photosensitive Material The material specification should be the first point to consider when starting the curing process. These are some of the typical electronics applications of conformal coatings, component adhesives, encapsulants, solder mask coatings and protective coatings. They can be used on rigid PCBs, flexible circuits, ceramic boards, glass, and metal-backed boards and thermally sensitive polymer films. UV and temperature are different for each substrate/material combination. Find out the recommended wavelength, minimum UV dose, range of acceptable irradiance and maximum temperature from the material supplier. The thickness of ...

Printing on PET, PVC, BOPP, PP film, synthetic paper, and other thermally sensitive media creates a narrow processing window. The ink must polymerize sufficiently for adhesion and abrasion resistance, while the substrate must remain dimensionally stable enough to maintain registration, web tension, and finishing accuracy. For this reason, UV LED Printing Curing should be treated as a controlled energy-delivery process rather than simply a high-power UV exposure step. Lamp geometry, scan overlap, working distance, ink thickness, substrate mass, cooling, and exposure sequence all influence the temperature history of the printed surface. Why Thin Substrates Develop Thermal Distortion A thin film has much less thermal mass than glass, metal, or rigid board. Even a moderate amount of absorbed energy can therefore produce a rapid surface-temperature rise. The resulting defect is not always obvious immediately after curing. Thermal stress may appear as: •   Transverse or machine-direction shrinkage; •   Edge curl after repeated print passes; •   Web-tension instability; •   Color-to-color registration drift; •   Distorted labels after die cutting; •   Wrinkling during lamination or rewinding. The problem becomes more severe with oriented films because their dimensional behavior depends not only on instantaneous temperature but also on residual stresses created during film stretching and manufacturing. ...

In UV adhesive bonding, high irradiance can shorten cure time, but it does not automatically produce a reliable bond. If the center of a work area receives substantially more UV energy than its corners, components processed in the same cycle can develop different degrees of conversion, cure depth, and final mechanical strength. For this reason, Uniform UV Intensity is one of the most important parameters in a repeatable UV adhesive curing process. It determines whether every critical point on a component receives enough energy to remain inside the validated curing window—not simply whether the lamp can achieve a high peak W/cm² value. What Uniform UV Intensity Actually Measures Uniform UV Intensity describes the spatial consistency of irradiance across the effective curing area. A practical expression is: UV Intensity Uniformity = Imin / Imax × 100% If nine measurement points across a curing zone produce a maximum of 820 mW/cm² and a minimum of 750 mW/cm²: Uniformity = 750 / 820 × 100% ≈ 91.5% This number is more useful than a single center-point reading because adhesive joints normally occupy an area rather than one optical measurement point. Process Variable Engineering Significance Main Risk if Uncontrolled Irradiance, W/cm² Instantaneous UV power ...