Laser cutting PTFE (teflon)

Can you laser cut PTFE (Teflon)? The answer is yes. PTFE can be successfully laser cutmarked or engraved. In this article we describe in depth what laser processing techniques can applied to PTFE and the results that can be achieved.

PTFE also known under the trade name of Teflon® or Algoflon® is a synthetic polymer used in many fields. The acronym stands for PolyTetraFluoroEthylene (PTFE). It is a plastic material, usually white in color though it can be colored black with additives. It can be used alone or in combination with other polymers.

PTFE belongs to Perfluorocarbons, a class of polymers composed mainly of fluorine and carbon chains.

Their chemical composition offers a wide range of properties which include:

  • Non-stickiness
  • Waterproof
  • Resistant to chemicals
  • Resistant to fire and high temperatures
  • High insulating power
  • Smooth

The applications are numerous. It is most commonly known for its use as a anti-coating material for kitchenware. But PTFE is also used to create gaskets, insulating tapes and in any other place where a component that reduces friction and resists corrosive agents is needed.

The fact that it is mainly composed of carbon makes it perfectly compatible with the CO2 laser wavelength. Laser cutting, perforation, marking and engraving on PTFE is easy and gives excellent results.

The interaction between PTFE and CO2 laser

The material interactions between PTFE and CO2 laser depend on the high insulating power of PTFE.

In general, when the laser beam reaches the surface of a material, it concentrates a very high energy in a single point. According to the characteristics of the material used, different chemical or physical transformations occur.

In the case of PTFE, the energy generated by the laser breaks the molecular bonds of the fluorine and carbon chains causing the chemical transformation of the material (laser marking) or its removal (laser cutting and engraving processes).

Being a material with excellent insulating properties, PTFE absorbs heat at the point of contact with the laser, without dispersing it in the surrounding area. It also has a high melting point. Both of these characteristics highly influence the laser’s behavior.

The poor thermal conductivity combined with the high melting point mean that the HAZ (Heat-Affected Zone) is very reduced. It is limited to the point of contact between the laser beam and the material.

As a result, laser processing on PTFE is very precise and clean. The chances of accidentally damaging the material or creating blackened or burned areas are very low. The fact that PTFE absorbs CO2 laser energy very well also makes processing very efficient in terms of speed.

Laser cutting Teflon

The PTFE laser cutting process works this way: the beam is used to remove material along a predefined cutting path. The removal of the material occurs by sublimation: the energy generated by the laser is concentrated in a very small area, and it is precisely the high energy density that causes the instantaneous passage of the material from the solid state to the gaseous state.

Laser cutting is used in many activities such as creating openings in a material, cutting out shapes from a sheet of material, making pieces from a matrix.

The peculiarity of laser cut PTFE is that its cutting edges are clean and perfectly finished and the obtained piece therefore does not require any further work. Laser cutting makes it possible to follow highly complex cutting paths.

PTFE Laser drilling

Laser drilling is a variant of laser cutting. It is also know as laser perforation.

In this process the laser is used to create a hole in a sheet of material, just like a mechanical drill would do. Laser perforation doesn’t suffer from the same limitation of traditional mechanical processing.

Microscopic holes can be created with laser technology. They can range in size from a fraction of a millimeter to the maximum area the machine’s design characteristics allow.

In addition, with laser technology, all the processing parameters (the inclination of the walls of the hole, the taper, the depth and density of the holes on the surface) can be controlled with great precision. It is possible to create pieces with all the characteristics best suited to the function they must perform. In the case of a filter, for example, holes can be created with precise dimensions, shape and arrangement.

PTFE Laser marking and engraving

PTFE also lends itself well to laser marking and engraving processing techniques. Marking and engraving are typically used to emboss logos, alphanumeric codes, barcodes or QR codes and various types of information on a particular material.

Both processes are based on the interaction between the laser beam and the surface of the material.

In laser marking, a chemical transformation of the material takes place and a the material is marked on the surface. In laser engraving, the material is removed. So, while laser marking takes place on the surface, in laser engraving the laser creates a groove in the material and the mark is carved into its surface. The choice of one process over another depends on the type of application or material being used.

On white PTFE, for example, laser marking gives poor results because the mark does not have high contrast to create a sufficiently visible mark. As mentioned, PTFE has a high melting point, so it is difficult to create burn marks.

Oppositely, on black PTFE, marking is more successful. At high temperatures PTFE expands and gives white marks which have a high contrast with the surrounding black background.

Laser engraving, on the other hand, can be performed on any type of PTFE with optimal results. As we have said, PTFE is an excellent absorber of the CO2 laser wavelength, but also a bad conductor of heat. This ensures that the area affected by heat is limited to the point of interaction between the laser and the material, resulting in a very precise and clean engraving.

Write to us to know more about how to process PTFE with CO2 laser.

Each laser application has its own particularities. There is no rule that applies to all circumstances and all materials. To find a solution that suits your needs, contact us, and we will be happy to find the best solution for you.

Peeling fruit with laser technology

group of chestnuts on a wooden table

Peeling fruit and vegetables using laser technology? It is possibile. And it is only one of the many applications of the CO2 laser for the food industry. Because of its wavelength, the CO2 laser allows you to efficiently process materials of organic origin.

The fast technological advance of the last few years have made the use of laser in the food industry now possible. El.En has been one of the first CO2 laser producers to study and experiment on its possible uses in the food industry. Laser technology can be used for cheese or cured meat marking, chestnut incisions, biostimulation, etc.

In this article we will describe another laser processing technique: the laser peeling of fresh fruit and vegetables.

How the processing mechanism works

The laser peeling process consists in using a focused laser beam to remove the skin of the produce. This is possible thanks to the elevated energy density that the laser manages to concentrate on a very small area. The process causes the immediate disappearance of a layer of material.

The thickness of the removed layer is very thin and essentially depends on the chosen parameters for the laser. Usually this layer corresponds to a few microns. This means that even if the energy and pressure would be very high, they concentrate on a tiny part of the organic material. Consequently, the zone affected by the laser is scarce and very focused, which is very important for the processing of food products. The result is that the organoleptic properties of food, such as flavor, freshness, texture and color, are in no way modified by the laser’s action.

Onions, peppers, tomatoes, oranges and lemons are only a few of the fresh produce that can be exposed to this type of laser treatment.

Laser peeling equipment

From a technical standpoint, the configuration of this type of system mainly requires a CO2 laser source, a laser scanning head and a control software. The advantage of this type of system is that even with a low power CO2 laser source, you can obtain great results. In general terms, the higher the laser power, the faster the operation and therefore the productivity of the system.

The process is based on the laser scanning of the product to be treated. By carefully regulating the parameters of speed and laser power, it is possible to configure the laser with extreme accuracy according to the results you want to obtain.

Contact us

Our company specializes in the use of laser for food processing. We can build a solution that works for your needs. If you think that laser peeling could be useful for your business, all you have to do di contact us!

Laser wire stripping with CO2 laser

Laser wire stripping is the process of removing all or part of the insulating material that covers electrical cables. In other words, it is the process used to uncover the metal core of the cables. It is typically done at the cable’s ends to make connections possible, but it can also be done in various ways along the cable.

Laser stripping’s main feature is that the laser selectively intervenes on the insulating material without affecting the cable’s metal core. This is a significant advantage over traditional stripping techniques. The high quality and precision of the laser striping process has made it a widely used technique in high-tech sectors.

Not surprisingly, the idea of ​​using lasers to remove the insulating layer of electrical cables was born in the aerospace sector. In the 1970s, NASA needed to find a solution to strip the thin Space Shuttle cables. The stripping tools used at the time did not guarantee the quality and precision necessary for an application of that type.

Traditional wire stripping methods and their drawbacks

The first is the mechanical method, which is the most widespread. In this process, blades are used to cut the electrical cables’ sheathing.

This method has many drawbacks:

  • to achieve accurate results, the process becomes extremely slow
  • each type of cable requires a dedicated tool
  • the tools require maintenance to remain effective

The risk of damage, for example notching the cable, is one of the main risks of this technique. To solve this problem, manufacturers have produced oversized cables, so that any loss of metal would not reduce the functionality of the cable.

While this may be a solution for low-tech industries, oversizing cables is not a suitable solution for others.

In the aerospace sector, for example, weight containment is essential. Cables are designed to be very thin so that they weigh as little as possible. This means that any damage to the cable could cause it to malfunction and lead to accidents.

In addition to the mechanical method, peeling can be performed with a chemical or a thermal process.

The chemical process uses corrosive substances such as sulfuric acid to dissolve the cable coating and expose the conductive material. The disadvantage of this technique is that it is not easily controlled and is also polluting.

The thermal process uses a heat source to remove the coating. This method, however, can leave residual coating material on the metal core which would therefore have to be subjected to further processing.

Laser stripping overcomes all the previously mentioned drawbacks. It is therefore not surprising that it has established itself as the method of choice for high-tech applications.

Why laser stripping works

In most cases, the material that coats electrical cables is some kind of plastic polymer while the internal core is made of metal, very often copper. Laser technology has the ability to select only the coating’s polymers without modifying the conductor in any way.

This behaviour can be explained by the way laser radiation interacts differently with different materials.

CO2 laser emits radiation at a wavelength of 10.6 micrometers, that is, in the far infrared [far-IR] region. Polymers absorb this radiation very well while copper reflects it almost completely, without undergoing alterations.

The advantages of laser stripping

Laser stripping offers several advantages over traditional methods:

  • flexibility: it is effective on almost all polymeric materials with which electrical cables are coated
  • precision: it is a non-contact process, which makes it able to work on very tight tolerances and to carry out processes that would be impossible with traditional methods
  • effectiveness: since laser is reflected by most metals, the process ends with the removal of the polymer without requiring any further processing

What are the different types of laser stripping

In laser stripping, the laser can perform 3 basic operations:

  • laser cross cutting: the cut is carried out transversely to the cable in order to allow the removal of excess material
  • laser slitting: the cut is made lengthwise. Typically this process is performed when a longer portion of cable needs to be removed and is used in conjunction with the cross cut
  • laser ablation: the laser passes over the surface several times until the coating is completely eliminated. This technique is mainly used when the conductive material is immersed in the coating (otherwise known as bonded wire).

Alongside these basic operations, laser technology makes it possible to perform advanced processes such as the partial and targeted removal of the coating with the creation of windows or the removal following certain patterns. All these applications can’t be done with traditional mechanical methods.

As is often the case with lasers, the possibilities are endless.

How a laser stripping system is made

A laser cable stripping system can be implemented in various ways and with various technologies.

The most effective is certainly galvo-scanning. In this application, a scanning head is used to move the laser beam and then focus it on the work surface.

The whole system is controlled by a computer which coordinates the operation of the CO2 laser source allowing the laser to follow the pre-defined cutting path.

Implement your own laser wire stripping

Laser cable stripping lends itself to many applications. It is ideal for high-tech sectors that require great precision during the processing phase. One of the applications, for instance, is magnet wire stripping with laser.

Don’t hesitate to contact us. Our staff would be happy to advise you on the best laser solution for your needs.

Laser Die Cutting vs. Rotary Die Cutting: an innovative technique for the packaging industry

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The introduction of lasers in industrial processes has been a small revolution: the effectiveness and versatility of this technology has allowed us to significantly renew diverse production fields. Especially the die sector has seen radical changes over the past years due to innovations in laser technologies.

Die cutting revolves all around the cutting, drilling, and shaping low-strength materials such as paper, cardboard, rubber, fiber, and cloth. Die cutting tools are mainly used in the paper and packaging industry, and are known to be robust.

Traditional Die Cutting

The creation of a die is a process that requires a lot of time, specialized technicians, and materials. This tool is thus not economically advantageous for manufacturers with small production quantities or large production variations.

  • The creation of a die requires the following steps:
  • Engraving a wooden board, needed to support the die.
  • Cutting and folding of the steel blade, to be inserted into the incisions of the base.
  • Fixing the blade on the die holder

The entire process must be carried out with utmost precision, as the blade must fit perfectly into the incisions of the support table.

It is thus clear that the die can be preliminary used for large and standardized production volumes. Small production volumes, prototype designs, or customized processes are bound to have high production costs.

The CO2 laser – an efficient and accurate tool

Market segmentation and the need to meet diverse and customized processes have led manufacturers having to search for innovative solutions. The CO2 laser, due to its characteristics, proves to be the best and most efficient choice.

The high power stability and the particular wavelength of this laser make it the ideal tool to cut paper and cardboard, typical packaging materials.

These packaging materials have the following characteristics: low conductivity, high combustibility, low gasification temperature, minimum thickness. These characteristics make the perfect conditions for the CO2 laser. With these conditions the CO2 laser is known to have a high running speed, while maintaining minimal energy consumption

Each laser process is characterized by accuracy and speed. The laser path is managed by the computer that “translates” the CAD design of the project into parameters such as power, speed, and position. In this way the laser beam produced by the CO2 laser source reaches the surface to be worked, causing the immediate evaporation of the material and therefore the realization of the process.

This process allows you to make cuts, perforations and engravings – in short all the operations of a die – in a fast, precise and flexible manner.

Faux leather laser engraving

The synthetic leather market has seen exponential growth in recent years. Natural leather is becoming an increasingly scarce commodity, both for economic and environmental reasons. On the one hand, the need for finished products at ever lower prices limits the use of expensive raw materials, and on the other, animal and environmental issues are driving companies to choose eco-friendly solutions.

Red synthetic leather: it can be laser marked successfully

Synthetic leather is very similar to natural leather from both a technological and sensory point of view. Unlike natural leather, it is not a breathable material. It also needs a base layer, often made of cotton or other natural fibres.

The advantages of synthetic leather over hide are many:

  • production costs are very low
  • the production batches are very uniform
  • textures and effects that do not exist in nature can be produced
  • it is easier to cut and sew

Far from being a less noble alternative to the original material, synthetic leather is a practical and modern material. It can be successfully used everywhere traditional leather was, with the same aesthetic and technical results.

The composition of artificial leather

Synthetic leather is made up of two layers, an upper one that imitates leather and a lower one acting as a base.

The upper layer is composed of a synthetic polymer. The most used materials are PVC (Polyvinyl chloride) and Polyurethane (PU). The two materials differ slightly. Most synthetic leather is made of PVC due to its low cost and greater resistance. Polyurethane, a costlier material, is less frequently used even though it feels more like real leather to the touch.

The artificial leather base is in fabric which can be made from synthetic fibres, natural ones (usually cotton) or even natural-synthetic blends.

The role of the fabric base is very important. The mechanical properties of synthetic leather rely on the strength of its base. The lifespan of synthetic leather is in direct correlation to the one of the fabric base.

Can you laser engrave faux leather?

The answer is yes, you can. Due to its thermoplastic polymer composition, synthetic leather lends itself very well to laser processing, particularly with CO2 lasers. The interactions between materials such as PVC and Polyurethane and the laser beam achieve high energy efficiency, ensuring optimal results.

Laser marking and engraving

The marking and engraving processes are very similar. In both cases, the laser beam acts on the surface layers. The laser energy activates alterations which, depending on the intensity, can be more or less deep or radical.

In marking processes, the applied energy density is very low. The material’s transformations stay at a superficial level and are more aesthetic in nature.

In laser engraving, the applied energy density is higher and reaches deeper layers of the material. It therefore undergoes substantial chemical transformations. The marking is more visible and contrasted. The end result can have a tactile finish and even a natural texture.

Laser parameters

The system must be set according to certain parameters to achieve the desired laser marking or engraving effects. There is no universal rule one can follow to set the system. The correct parameters depend on factors such as:

  • the type of material used: polyvinyl chloride and polyurethane absorb energy differently. So the settings must be regulated differently.
  • the colour of the leather: light coloured leather is more reflective than a darker one. Dark leather therefore absorbs the laser beam better, resulting in greater energy efficiency and faster processing.

A correct laser setting will aim to achieve the correct energy density in order to obtain a clearly visible mark without damaging the material.

Laser Engraving Systems

Leather marking/engraving is one of the applications of galvo scanning. This category includes all processes in which the laser source is used in combination with a scanning head.

The scanning head distributes the laser beam produced by the source on the material’s surface.

Laser sources and scanning heads are available in different models depending on production needs. In order to make the right choice, it is necessary to know your particular manufacturing characteristics. Send us information about your production plant and requirements and we will be happy to design a tailor made leather laser marking/engraving system to suit your needs.

Laser Engraving Fashion Design: a sustainable application

laser-marking

The clothing industry is the second biggest polluting industry, being just behind the petrol industry. To give you an idea of the massive impact the fashion industry has on the environment, consider this: it is estimated that 10% of world’s greenhouse gas emissions are generated by the textile industry.

The textile industry is all but harmless to the environment since its production processes consume a lot of resources such as water, energy and chemicals for the finishing process. This has led the industry to research more sustainable and eco friendly processes.

One of the most polluting phases of the production processes in the clothing industry is the finishing process, e.g. fabric decoration. Research shows that laser technology currently is the most eco friendly and sustainable application that can be used to decorate clothing and fabric. Not only did the laser technology stand out as a viable and efficient technology, but it also allowed designers to innovate products and designs.

To be honest, the use of laser technologies in the clothing industry is not entirely new, but dates back to the early 60’s. From that moment on, researchers noticed the diverse advantages of this technology, such as precision and lack of wastes. After years of research, experimentation and applications, the CO2 laser has proven to be the most suitable technology for the fashion industry. The use of the CO2 laser is beneficial in terms of design as well as in terms of the company’s resources. All desired designs can be achieved, with millimetric precision, by applying the very vast and efficient laser marking processes on the fabric. The energy efficiency and the running speed of a CO2 laser source are incomparably superior to any other traditional production technique, resulting in a significant decrease of energetic resources. Furthermore, the technology solely modifies the surface of the material – this means that there is no need for water consumption or polluting chemicals.

Laser engraving for fashion design does not know limits in terms of versatility. Nearly all materials normally employed by the textile and clothing industry can easily be worked by the CO2 laser. The technology can engrave or mark either natural or synthetic fabrics. Recent studies have also revealed that this technology is highly suitably for the discoloration of clothing, in particularly jeans cotton.

The CO2 laser is especially suitable for the clothing industry due to its particular wavelength, which is well absorbed by non-metals and organic materials as they are bad conductors of heat and electricity. This allows you to achieve optimal results while consuming the least possible amount of energy resources. Inks, chemicals, and solvents are eliminated and there is thus no longer a need for large amounts of water: the eco-sustainability of the CO2 laser is thus evident.

This is also demonstrated by a recent study1 that analyzed the outcomes of laser decoration and innovative designs on wool and polyester fabrics versus decoration achieved by means of chemicals. The research paid particular attention to the weight, thickness, perspiration, thermal conductivity, and strength of the fabric after they had been engraved or marked. Both production methods have been tested with simple as well as complex patterns. The results have shown that the laser technology method performed better in all of the above named aspects, in comparison with traditional methods.

Besides that, the laser technology has also shown better results in terms of speed, precision, and resource consumption.

In conclusion, laser engraving for the clothing and textile industry is a more efficient, sustainable, and eco-friendly process than traditional methods of decoration.

1Application of Laser Engraving for Sustainable Fashion Design, G.X. Yuan, S.X. Jiang, E. Newton and W.M. Au, Research Journal of Textile and Apparel 2013 17:2, 21-27.

Label laser die cutting

Laser die cutting of labels is a digital converting process. In this application, the laser die cutter replaces mechanical dies in the execution of processes such as the cutting or trimming of label templates.

The use of laser technology is particularly advantageous. On the one hand, it overcomes the typical disadvantages of mechanical die cuts. On the other hand, it allows the same processes to be performed with a flexibility and precision impossible to achieve with diecuts.

In this respect, the laser die cutting process clearly shows the advantages of using lasers for labeling and packaging applications.

How the label production process works

The production of self-adhesive labels is one of the most traditional papermaking operations.

Typically, the label production process takes place in 3 steps:

  • printing of the label on the master sheet
  • engraving of the label template
  • cutting of the label template

The die cutter is used for the operations of engraving the label and cutting it out from the master sheet to isolate the label from the sheet itself.

This processing technique has several disadvantages:

  • in order to obtain new shapes to cut, manufacturers must create a new die cutter
  • the mechanical properties of the tool do not allow complex shapes to be cut
  • the cutting tool wears out quickly and needs maintenance to work efficiently

Given those features, a mechanical production system is only efficient if it can guarantee high production volumes. However, the market today rewards companies that are able to offer innovative, customised production processes that can support numerous orders with small production volumes. And from this point of view, a laser cutting machine is the optimal production tool.

Laser processing of labels

Laser die-cutting is based on an ablation process. The operation is carried out by a laser machine. The beam laser power, focused on the material, removes a portion of material through a chemical process called sublimation. By means of devices such as galvo laser head, it is possible to move the laser beam along a determined path. Digital control also makes it possible to precisely calibrate the instrument according to the desired type of processing. The operation is carried out at high speed.

There are two possible operations: laser kiss-cutting and laser cutting. Both are laser cutting processes, but differ in how deep they cut the material.

Laser kiss-cutting and laser cutting

Laser kiss-cutting consists of cutting the surface layer of a multilayer material. Adhesive labels are printed on master sheets. These sheets typically consist of two layers: a top layer on which the graphics are printed and a backing layer, onto which the adhesive is glued. In laser kiss-cutting, the laser engraves only the surface, freeing the adhesive template from the backing matrix.

In laser cutting, the beam passes through all the layers of material, freeing the adhesive from the matrix and reducing it to a unit.

The advantages of laser label die cutting

Laser finishing offer numerous advantages:

  • the cutting path can be modified by simply loading a new file into the system
  • the absence of mechanical contact allows particularly complex cutting paths to be followed
  • laser cutters does not wear out and requires minimal maintenance

For a company using a digital laser die, it becomes possible to manage production in an innovative way. It can now make prototypes for the customer, start small volume production runs and accept numerous orders that wouldn’t be sustainable with traditional production methods. It is a true paradigm shift in the way we conceive production.

There is yet another advantage. In the digital converting industry, and particularly in paper converting, CO2 lasers are almost exclusively used. These laser systems are known to interact very efficiently with paper materials. This characteristic, coupled with the reduced production of processing waste, makes the laser an eco-friendly production tool.

Contact us

El.En. has developed numerous digital converting applications over the years. Contact us to find the application that best suits your needs.

Glossary: laser microperforation

Holes drilled on the surface of a material

Microperforation is a laser process that consists in creating micro holes on a sheet of raw material. Microperforation makes it possible to precisely choose the size, depth and quantity of holes per square centimeter. The flexibility of this technique makes it easy for the operator to change the processing characteristics according to the intended final use of the piece.

There are many examples of this processing technique from various sectors:

  • the paper industry where microperforation is used to create security paper, i.e. paper products with special features to make counterfeiting very difficult
  • the industry of fabrics and leathers, microperforation can be used to add decorative elements but also to improve the breathability of materials
  • a similar application is in the automotive sector, where for example, microperforation is used in the finishing of leather for the internal lining of cars
  • the packaging sector, microperforation is widely used. It is used to microperforate the plastic film used for packaging in modified atmosphere because the size and density of the holes can be adjusted with great precision
  • Finally, a last example comes from the field of soundproofing. Sound absorbing tiles that perfectly muffle a specific type of frequency, are made with laser microperforation

The advantages of laser microperforation

Microperforation has several advantages over traditional applications. Here are two:

  • Precision. Laser can perfectly calibrate the density, number, size and internal shape of the holes. Microperforation therefore allows you to create processes perfectly suited to the intended use of the product
  • Flexibility. Different materials can be processed using the same laser source. CO2 laser sources are unbeatable for their flexibility of use

What materials can be processed with laser microperforation?

CO2 laser microperforation works best on flexible natural and synthetic materials. Some of them include:

  • thermoplastic polymers, materials such as PMMA, polyethylene, PP and PET are among those most used in the packaging sector and suitable for this type of processing
  • leather and hides
  • fabrics made from natural and synthetic fiber
  • paper and cardboard

Which laser source to choose to execute laser microperforation?

There are many factors to take into consideration when choosing the right laser source for microperforation.

One must consider the material being processed as well as the desired production outcome and process speed. Based on these elements, it is possible to establish the best wavelength and the power to use to get the job done.

Although finding the laser solution that best suits your needs may seem impossible, don’t worry, our experts have extensive experience on the field and will be able to help you find the laser system that’s right for you. Contact us for more information!

Hermetic laser sealing of plastic food bags: what it is, how it works, and the advantages

Yellow pear in plastic bag

Let’s continue our journey of discovery of the different CO2 laser applications for the packaging industry. In the past articles, we’ve already described how laser micro-perforation can drill accurate holes on plastic film to create packages suitable to preserve fresh food. Laser micro-perforation applications, unlike traditional mechanical micro perforation applications, offer speed, flexibility, and extreme accuracy.

In order to improve the shelf life of products, it is often necessary to continuously control gas exchanges between the interior and the exterior of a plastic bag. Laser micro-perforation allows us to tightly control these gas transmissions, allowing us to easily package fresh products as well as preserve their quality.

It is no coincidence that the CO2 laser has seen a broad application in this field. The packaging industry knows very strict production rules and specifications. Packaging must not only guarantee the quality of the product, but must also meet requirements in terms of mechanical strength, packaging hygiene, and food safety. Besides that, all requirements also have to be reconciled with an aesthetic appearance. Poor packaging could reduce the perceived quality of the product, and is thus a crucial factor in influencing consumer buying behavior.

In this article we’re going to describe another application of the CO2 laser: we will talk about sealing plastic food bags.

Conventional methods to seal plastic food bags

Why is the CO2 laser an innovative process for the sealing of food bags? To get an answer to this question we have to briefly discuss the traditional methods used to seal plastic food bags.

Traditionally the sealing of plastic food bags is a welding process achieved through the application of heat and pressure. In this process, two sheets of plastic film are joined and welded together. This process is mostly mechanical, meaning that parts of the machine have to be changed every time a different packaging process is executed, in order to meet the packaging needs of diverse products. Traditional machines are heavy, due to their working parts that need to be fastened securely.

A production line of this kind is not flexible, while food manufacturers may need to apply different packaging techniques within the same production cycle. This would mean that the manufacturers have to the change machine parts or perform other maintenance operations, which results in lower productivity.

Laser hermetic sealing plastic food bags

The process of laser sealing of plastic bags is part of the hermetic welding process of thermoplastics. The most commonly used bags in the packaging industry are transparent and made of polypropylene or polyethylene.

These materials absorb the 10.6 μ wavelength of the CO2 laser very well. The laser beam reaches the surface of the material to be welded thanks to a scanning head. Subsequently, the laser heats up the surface so as to reach the melting temperature of the material, allowing it to weld the two plastic films together.

The entire process is incredibly fast: the speed achieved with this welding method to hermetically seal plastic bags allow to seal dozens of pieces per minute.

What are the advantages of hermetic laser sealing?

The advantages of using a laser sealing system to hermetically seal plastic food bags are endless:

  • You can change the shape and size of the packaging material to be sealed without the need for long breaks in the production flow. It is not necessary to create custom-made parts since the laser can be applied to any type of container and to any type of machining even within the same production cycle.
  • The sealing can even be carried out on very thin plastic films without risking any damage to the material. This allows extremely accurate machining operations and reduces the amount of material used, and thus reduces industrial waste.
  • The CO2 laser is compact in size and light in weight since mechanical parts or other bulky mechanisms are not required. The laser system thus fits well into production facilities with confined spaces.
  • Like any other laser process, the welding of plastic bags is a non-contact process. This means, among other things, that it is aseptic, and thus perfect for the packaging of food products.

Required components for a laser system setup

You may ask yourself right now which components are required for a laser system set-up. It is difficult to define in detail the diverse components or elements that will be part of the system. Each customer has its own needs in terms of power, production speed, material to be treated, etc. However, it is possible to define the following three basic elements of a similar system.

CO2 Laser source

The CO2 Laser source generates the laser beam that will work your materials. El.En. CO2 laser sources are available in different output powers, ranging from 150W to 1200W.

Laser scanning head

The laser scanning head is a device that “moves” the laser beam while keeping it perfectly focused on the point that needs to be worked. El.En.’s scanning head executes this process at very high-speed thanks to the beryllium mirrors mounted on galvanometric motors.

Control Software

The advantage of laser processing is that the entire process is controlled digitally. Through the software, you can control all relevant machining parameters and perform on-the-fly changes without interrupting the process workflow.

6 advantages of laser manufacturing abrasives materials

Abrasives, part of a family of materials characterised by their great hardness, are used for processes such as polishing or the sanding of surfaces. They are available in a wide variety of shapes and types and lend themselves to a multitude of processes.

These materials can be moulded into a large number of shapes: discs, brushes, wheels, cutters, grinding wheels. However, traditional abrasive processing methods have limitations that can be overcome with laser processing.

In this article we will look at the 6 advantages of using laser technology in the manufacturing process of abrasive products.

1. Laser is a non-contact process

The main problem in the manufacturing of abrasives is that the abrasive action is also exerted on the tool itself. Let us take flexible abrasives as an example. In this category of abrasives, the abrasive substance is sprinkled on a backing, which is normally made of paper or a polymer material. In order to obtain the desired shapes, such as a rotating disc or wheel, tools such as dies are used, i.e. a mechanical method that uses contact between parts to separate an element from the die into the desired shape.

Operations such as die cutting of abrasive materials, however, have a drawback. The abrasive action is also exerted on the cutting tools. Blades, dies and cutters quickly get worn out and must be replaced frequently to maintain high machining quality. This increases machining costs, which consequently increases the cost of the final product.

Laser cutting of abrasive materials overcomes this disadvantage. It is characterised by a total absence of contact. The laser beam interacts remotely with the surface of the material in a non-mechanical process that avoids the problem of continuous wear of the machining tools.

2. Laser is a versatile tool

A major disadvantage of traditional machining methods is also their lack of flexibility. For example, a die made to create a specific shape can only be used to create that specific shape. To make differently shaped parts, it is necessary to create new diecuts, provided that the investment required to create them is justified by a profitable return.

Similarly, only one machining operation can be performed with traditional machining tools. A die-cutting tool can only perform one machining operation. A cutting tool can only perform cutting. To perform different machining operations, one must change the machining tool. If a manufacturer wanted to apply information to an abrasive disc such as grit size or a serial number, he would have to insert the part into a dedicated machine, such as a printing machine.

Laser systems, on the other hand, allow several machining operations to be performed in a single session. With the same system, flexible discs can be cut from a die, cuts and perforations can be made and surface information on a material can be added through laser marking. In addition, the use of lasers allows the shape or size of the piece being manufactured to be changed in real time, without any additional aids. It is precisely its high flexibility that makes the laser the trump card for this type of application.

Laser offers a true change in the very way production is understood. It gives manufacturers the possibility of enormously expanding their commercial offerings. It becomes possible to create prototypes, just-in-time production, or series of small parts for high-value customers.

3. Laser is a precise tool

Abrasives are used in many different industries. Each of them requires specific processes, and, therefore, abrasive tools that are shaped differently. This means that there are more or less specialised tools: from simple sandpaper, sold in rolls and used by carpenters and craftsmen, to customised rotating discs for high-precision machining.

However, mechanical machining tools have a tolerance limit beyond which they cannot go. The size of the machining tools, their design, and the need to avoid unwanted contact limit the complexity of the machining that can be performed.

Laser, on the other hand, allows very tight tolerances. Since there is no contact between the parts, the tool can follow intricate cutting paths, create microscopic perforations and special shapes, make surface cuts and other machining operations that would be impossible with mechanical cutting tools.

4. Laser reduces machining waste

With traditional machining tools, processing is performed by the mechanical removal of material. The process tends to produce machining waste, dust and other residues that must be managed in some way, with a variable economic and environmental cost.

Laser machining processes, on the other hand, tend not to produce waste. Material removal occurs through sublimation. The very high energy density produced by the laser on the surface allows the temperature of the material to rise, instantly vaporising it as a result of a transformation of the material state.

5. Laser respects materials

Mechanical machining processes present a risk of damage to products due to accidental contact or excessive mechanical contact. Any deformation lowers the quality of the final product.

In laser processing, there is no risk of damage from mechanical contact. Laser processing respects all materials, even the most delicate ones. They guarantee a higher quality of the finished part and are therefore ideal for the sectors in which the degree of error must be kept down to a minimum.

6. Laser is an environmentally friendly process

Laser processing offers high energy efficiency. All things being equal, laser performs the processing with much lower energy expenditure than mechanical processing. This, combined with the absence of waste, makes the laser one of the most environmentally friendly processing tools available to manufacturers.

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Laser is a cost-effective tool for the manufacturing of abrasive materials. Because the possible applications are numerous, seeking the advice of an expert can help you find the most suitable processing system for your application. El.En. CO2 laser systems are ideal for the manufacturing of abrasive materials. Contact us for more information.