How to determine the best light source wavelength for UV cured adhesives

It's a pity.,My other number can't reply to you.,The answer was deleted for no reason.。。。 The situation you listed is caused by incomplete curing 1. You need to understand the power density of the curing lamp required by UV, and judge it in combination with the power of the lamp itself (how many W cm, converted according to the length of the luminaire and the power), whether the existing lamp can meet the requirements of complete curing, if not, it needs to be replaced. 2. By extending the curing time, check whether it can be fully cured.

Speed adjustment: 1) The best speed selection method: the product first passes through the UV light curing device at a certain speed, and if it is cured, then speed up until the product passing through the curing device can not be completely cured, and the speed is multiplied by the best speed.

2) In addition, we should also pay attention to the use time of the UV lamp, with the extension of the use time of the UV lamp, the energy will decay, and the speed should be slowed down, at this time, the new UV lamp should be replaced in time. 3. Check whether the surface temperature is too low during processing due to air cooling, and then make appropriate adjustments.

UV curing adhesive.

It is a UV-curing adhesive, a type of adhesive that must be cured by ultraviolet light.

How to use: 1. One of the two objects to be bonded is transparent and the surface is clean, dry and grease-free;

2. Apply UV shadowless adhesive on one of the surfaces, close the two planes, and irradiate it with a UV lamp or high-pressure mercury lamp with appropriate wavelength (usually 365nm 400nm) and energy.

3. It is recommended to remove the remaining glue on the workpiece and then re-illuminate it to complete solidification when the light is about 6s and initial positioning;

To determine the right curing time for a UV glue, we first need an important tool, and that is a radiometer. A radiometer can tell you how much light intensity is at the glue line. The different methods depend on how you use the adhesive.

If adhesive is applied between two substrates, the adhesive line thickness is typically. For example, the UVLED flood light source of Yuntong Technology, the light intensity is generally greater than 1000MW cm, and under the irradiation of this light intensity, the curing time of this kind of glue method is generally 2 3s.

Of course, each glue is marked on the TDS with its required curing energy, and the curing time at this light intensity should generally be less than 5s. If you potting a deeper section, the depth of cure is important. Loctite TDS typically measures the depth of cure at 50 MW cm, and this is similar to this for clear glues with a cure depth of 1 mm.

For the curing energy or curing time described by TDS, we can only use it as a reference, and the most important thing is to test it ourselves. This is the best way to calculate the correct cure time, whether looking at the holding time, the depth of cure, or the drying time. To set the minimum light intensity on the glue line, you can use 50 MW cm.

This can be done by increasing the distance of the lamp until the radiometer measures an intensity of 50 MW cm. (The machined part starts from a high light intensity, and there is room for variation in light intensity and time, which can control the machining process.) ）

After setting a fixed light intensity, the adhesive is cured for different periods of time. You can see that tensile strength, compressive strength, dry time, depth of cure, hardness or other data points climb to a maximum and then enter the stabilization phase. Once you've identified the starting point of the stabilization period, add a safe range, and you've got the underlying process.

You can also set the time constant, change the light intensity, and then dose the same data point. By knowing the maximum and minimum light intensity and the time it takes to cure the glue, you can determine your process.

The curing principle of UV adhesive is due to the polymerization reaction between the photoinitiator in UV adhesive and ultraviolet light, and the sinwe UV adhesive has no bubbles, no whitening, no adhesive traces, high bonding strength and fast curing speed. XCvoc UV glue curing lamp adopts LED light source, which is energy-saving, environmentally friendly, economical, efficient, long life, 5 seconds of dry watch 30 seconds, 50,000 hours of working time, no heating.

UV adhesive can be positioned in a few seconds and reach the highest strength in one minute, which greatly improves the work efficiency; Completely transparent after curing. The stronger the UV rays, the faster the curing speed, with a general curing time ranging from 10 to 60 seconds.

Compatibility can be used for temperature, solvent and moisture sensitive materials.

Control curing, waiting time can be adjusted, and the degree of curing can be adjusted.

The sizing can be repeated and cured multiple times.

UV lamps can be easily installed in existing production lines without major modifications.

Shadowless glue gluing process Shadowless glue, also known as ultraviolet glue, it must be cured through the premise of ultraviolet irradiation to the glue, that is, the photosensitizer in the shadowless glue will be bonded with the monomer when exposed to ultraviolet rays, and theoretically the shadowless glue will almost never be cured under the irradiation of the ultraviolet light source.

There are two types of ultraviolet light: natural daylight and artificial light source. The stronger the UV rays, the faster the curing speed, with a general curing time ranging from 10 to 60 seconds. For natural sunlight, the UV rays in the sunlight will be stronger on a sunny day, and the faster the curing speed.

However, when there is no strong sunlight, artificial ultraviolet light sources are used. There are many types of artificial ultraviolet light sources, and the power difference is also very huge, from small power to a few watts, and high power to tens of thousands of watts.

Different manufacturers produce shadowless adhesives or different models with different curing speeds. Adhesives used for adhesives must be irradiated with light in order to cure, so adhesives used for bonding can generally only bond two transparent objects or one of them must be transparent, so that ultraviolet light can penetrate and irradiate the glue.

On the whole, the curing time of the industry of UV glue is within 3-15, this data is the result of the application of UVLED light source, which is much faster than the traditional UV lamp, and the traditional UV lamp curing machine takes a few minutes.

If it's a WKM-1S UV spotlight it will be faster:

According to the specific UV adhesive and the curing lamp used by the customer, it cannot be generalized, and it needs to be determined by experiment. If the UV light intensity is high, the irradiation time is short, and it can be cured, and vice versa.

XCvoc ultraviolet lamp is a 365nm + 395nm wavelength ultraviolet lamp, also known as UV lamp, which can cure shadowless glue (UV glue) and ink within 30 seconds, with instantaneous curing, time-saving and power-saving, space-saving, easy to control, no need for high-temperature baking, wide adaptability to the substrate, no pollution and other advantages. It is suitable for nail art, phototherapy, glass sliding door curing, strengthened glass curing, crystal processing curing, coating curing and other low-temperature and rapid curing fields, and has no harm to the cured carrier.

UVA glue curing machine UVLED UV curing lamp:

WKM-1A, High Power UVLED UV Lamp: 2-3S curing.

The ultraviolet light reacts with the photoinitiator of the UV glue and then cures.

UV light curing machine, fast curing, 3-5s time.

WKM-1A spot light curing is for dispensing curing.

Ultraviolet UV glue, referred to as UV glue, is considered to be an environmentally friendly green technology, also known as 3E technology, that is, energy saving, environmental protection, economy, mainly used in coatings, inks, adhesives and other fields.

UV curing UV glue is a kind of photoinitiator in the glue and cured by chemical reaction with ultraviolet light, sinwe UV glue has no bubbles after bonding, no whitening, no adhesive marks, high bonding strength, XCvoc ultraviolet curing lamp, 3 seconds positioning, 30 seconds full drying, LED light source life up to 50,000 hours.

Temperature, glue type, quantity, humidity and wind speed.

Temperature Warning: The higher the ambient temperature, the faster the curing; The lower the ambient temperature, the slower the cure.

Glue Category: Fast-formulated glues will have a more "youthful" power than slow ones, and low-viscosity glues will have shorter curing times than high-viscosity glues because they evaporate faster.

Quantity: Excessive use of glue at room temperature will slow down the curing rate due to the longer evaporation time required, and excessive glue will increase the permeation and may compromise the integrity of the joint.

Humidity: The higher the humidity, the slower the speed, because too many large soda molecules slow down the volatilization of the glue at the interface.

Wind speed: When the wind speed at the bonding site reaches or exceeds 10 miles, the acceleration of the volatilization rate will lead to the acceleration of curing, and the drying high temperature is the main factor.

UV glue, the main nucleus is cured by ultraviolet light, and the length of curing time is mainly determined by the modified wavelength of the UV lamp. The best curing wavelength for common UV adhesives on the market is UVB light, which is the wavelength of 365-400nm. The wavelength of ultraviolet rays is not enough, then the glue cures very slowly, and the color of UV glue, the higher the transparency, the faster the curing speed under the same wavelength UV lamp, the color will be relatively slow, the darker the color, the slower the curing speed, the surface of the UV glue, the surface curing effect is good, part of the bonded UV glue, there will be a layer of surface can not be cured when there is no adhesive surface, giving people the feeling that it is oily.

If it's natural light, it depends on the intensity of ultraviolet light.

If you use ultraviolet lamp, it also depends on its power.

The main factors that affect the curing time of UV glue are UV exposure intensity and area.

Temperature and humidity can affect.

UV glue is a kind of glue that uses ultraviolet light to cure quickly after irradiation, so its curing time can be determined by controlling the ultraviolet exposure time. The following is the specific method of determining the curing time of UV glue:

Preliminary setting: First of all, before the actual use of the material, you can conduct a preliminary inferior inspection of different UV glue brands or styles, and roughly understand the curing time and the characteristics and state data of the processing itself that need to be followed by the group filial piety.

Device pre-calibration:

By adjusting the parameters such as light output and light intensity of the light source, the UV lighting equipment can be fine-tuned in advance, which helps to maintain the robust light output quality and spectral light transmission elements, so as to achieve better results and more conveniently.

Multiple Experiments: In order to accurately determine the UV solidification and friendization time, it is best to perform multiple tests and record the curing time of each test until the best results and adhesion strength are achieved.

Consider other factors:

In addition to the UV exposure time, other such as the type of glue, the ambient temperature, the thickness of the glue, the size of the curing area or the size of the curing area will also affect the curing time of the UV glue, which needs to be adjusted and calibrated appropriately according to the actual situation.

In general, the curing time of UV glue is very important in the process of mass production or large-scale production, and it is necessary to comprehensively consider multiple factors such as equipment, environment and UV glue quality to ensure the stability and excellent completion of production and operation, and pay attention to the accurate recording of operation data in the experimental process and the specific spectral color temperature and optical device parameter elements used in each test, which is helpful for later management capacity training, feasibility assessment and curing durability statistics.

The ultraviolet lamp is irradiated for about 10-20 seconds for preliminary curing.

Does the curing time of UV glue change?

As a professional manufacturer of UVLED curing equipment and UV glue, Yuntong Technology has always been committed to providing customers with fast-curing adhesive solutions, and the previous article also shared a lot of knowledge about UVLED curing equipment.

With the more and more widespread use of UV glue, UV glue curing reflects a series of problems, the most important is that UV glue curing is easily affected by a variety of factors, so what specific factors affect the curing time? Temperature, type of glue, quantity, pipe radius, temperature and wind speed can all change the curing time of the glue.

Curing. jpg

It is related to the following factors.

1.Temperature: The higher the temperature, the faster the curing speed, and vice versa.

2.Glue category: Glue with fast formulations cures faster than slow formulations; The low viscosity cures faster than the high viscosity.

3.Pipe diameter: The larger the pipe radius, the greater the gap at the interface between the pipes, and the more glue used to dry the pipes.

5.Wind speed: When the wind speed at the bond exceeds a certain level, the curing speed will be significantly accelerated.

6.Number of uses: Excessive use of glue at room temperature will take more time to dry because of slow evaporation, and more notably, excessive glue will increase the amount of penetration and compromise the integrity of the joint.

In the case of a certain UV glue, the irradiation intensity of the UV lamp and the curing energy have a great impact on the curing effect

1. The effect of UV irradiation intensity on the curing effect of UV adhesive.

Too strong UV irradiation intensity has a certain negative impact on the performance of acrylic UV adhesive. For example, increasing the irradiation intensity n times can increase the efficiency of the initial reaction rate by n times, produce n times the free radicals, and increase the growth rate efficiency by n times; However, at the same time, the speed of terminating the reaction will be increased by n2 times, which greatly accelerates the curing speed of UV adhesive.

In other words, too strong UV irradiation intensity will cause the molecular weight of UV adhesive to decrease, and the chain ends of molecular chains will become more numerous, but the best adhesive strength cannot be obtained.

2. The effect of UV irradiation energy on the curing effect of UV adhesive.

Experiments show that for the UV glue of acrylic system, it is better to have too much irradiation energy than to avoid insufficient irradiation energy. Whether it is theoretical or practical, even if the UV irradiation energy of the acrylic system exceeds 10 times the original recommended value, there will be no obvious negative impact. It is speculated that the irradiation energy may exceed the design recommendation value by hundreds of times, and the ultraviolet photoaging reaction will be more obvious.

Therefore, the above factors should be considered comprehensively when determining UV lamps and equipment, so as to obtain appropriate curing process parameters, so that the products cured with UV glue can achieve a more ideal curing effect.