Laser scoring for the packaging industry

Laser scoring is a wonderful technique to create advanced features on flexible packaging. Together with laser perforation it lets designer conceive easy opening packages, single portioned or disposable boxes, tear-apart openings that can enrich the experience of the product.

The rising success of easy to open packagesย has pushed producers to look for new packaging solutions.ย More than ever, consumers are used to easy-opening packaging.

The introduction of laser technology and digital converting processes has pushed packaging companies to find innovative solutions that were unthinkable of just a few years ago. Industrial lasers for packaging, such as the CO2 laser, give added value to a product by not only protecting it, but also making it easy to open.

Flexible packaging bags

Plastic film packaging, which has offered a wide scope for experimentation, is a perfect example of the added value of packaging.

As discussed in previous articles, CO2 laser can increase the breathability of the plastic film according to the product they contain. Fresh produce, for example, can be wrapped in micro-perforated bags in a modified atmosphere room to extend its longevity.

Laser scoring on plastic film bags to make packaging easy-to-open is another laser application that has many uses.

What is laser scoring?

A laser beam vaporises predetermined areas of a plastic film, thus creating the scoring. The weakening line that is created makes the packaging easy to open without the use of tools.

Bag with tear apart features

Laser incision has the advantage of removing the material in a precise and uniform way. This technique gives the possibility to closely control the depth of incision. By removing only the strict minimum amount of material, the integrity of the packaging remains untouched.

The right materials for laser incision

Laser incision is ideal for flexible packaging made in plastic film. These materials, which are some of the most commonly used in the packaging sector, are perfectly compatible with CO2 laser:

Plastic film packaging can be used for all kinds of products: food, cosmetics, chemical products, herbal and pharmaceutical products.

Laser scoring technology

There has been a paradigm shift in the world of packaging since the introduction of laser technology. We have shifted from the mass production of standardised products to the small production of highly tailored products.

This change has only been possible because laser technology is a digital production tool. It can be completely controlled via software and is fully automated. A scoring laser system can be designed right from the beginning of the process and can work in analog work flows. Regardless of the type of work flow, laser technology brings added value to the production process, making it simple and fast.

Laser incision is a very versatile tool since the depth of incision can be controlled. By loading different vector files into the system, you can easily and quickly go from scoring to cutting through the material.

A bag made of flexible packaging

The laser can make incisions in a straight line, following the reelโ€™s movement (down web?) or even transversally. The movement of the laser scoring is completely defined by the user. It can follow a straight line, the contour of a shape or a freeform path.

Laser technology is ideal for scoring because it is a contactless process. The lack of physical contact makes it possible to avoid problems such as the accidental rupture of the plastic film or the use of cutting tools. In order to achieve a high quality incision, the blades had to be perfectly sharp and therefore frequently changed. Production would to come to standstill in order to change machine parts which resulted in higher production costs.

The use of laser technology make all these problems obsolete. The only maintenance laser needs is a periodic gas refill. And now, with El.En.โ€™s self-refilling technology which allows the laser source to be recharged autonomously, even this minor inconvenience can be avoided.

The right laser source for laser scoring

In conclusion, the CO2 laser is ideal for scoring of plastic film. The previously mentioned materials respond well to the CO2 laser wavelength. The laser scoring process works best with a low power laser source or with up to a 300 W power supply. One should also take into consideration that the higher the laser power, the faster the production.

The possibilities given by system integrations and configurations are endless. Once the type of application has been decided, it becomes easy to choose the best configuration.

Laser labeling of food: a complete guide

Fresh whole bio mango isolated on black background

A mango fruit with a laser marked sign on it

Laser etching of various pieces of information on fruit, vegetables and other food products is an innovative procedure that is replacing traditional methods otherwise used in the field. A CO2 laser can not only etch alphanumeric codes and barcodes, but also any type of graphical representation.

This versatility can easily makes it possible to replace traditional methods such as hot-marking, inkjet printing and adhesive labeling. CO2 technology also guarantees huge savings in terms of speed and resources. Because of the previously mentioned reasons, there has been a growing interest in laser marking of food products.

In this article we will present a general overview of laser labelling for food. We will show its main fields of application, the advantages it delivers to both the production process and the environment, the way it works and the technologies employed.

Apples on a conveyor belt in an industrial plant

Laser labeling for food: fields of application

Food products make large use of codes, labels and other varying symbols. They serve many purposes: guarantee the safety of consumers, trace products through the various steps of the supply chain and fight the counterfeiting of products. Here is some of the information you can find on products:

  • alphanumeric codes like expiry date, batch code or PLU codes
  • barcode or QR code
  • logos and commercial brands
  • controlled origin symbol

This information can be applied to the product in different ways:

  • fire branding for products such as cheese or cured meats
  • ink printing for products with non edible shells like eggs
  • adhesive labels for fresh produce

The use of lasers in the food industry isnโ€™t new. Production technology has long discovered the potential of this tool. Its use centered around process control (for example, reading barcodes), bio-stimulation of produce or disinfection of products through laser with ultraviolet wavelength.

The method of laser markings on produce to replace labeling has been known for several years. The first patent dates back to the end of the 90s. This process hasnโ€™t yet become widespread though. The high cost of laser equipment combined to the lack of specific knowledge about the process has made most producer continue using traditional methods which are quite fast and inexpensive compared to laser.

Pears ready for processing

In recent years, interest in laser technology has grown to the point that it is no longer only within the purview of specialists. Some famous companies in the produce sector have chosen to adopt direct laser labeling of their products. Many factors explain this shift from traditional labeling techniques to natural branding. The cost of laser technology has gone down in recent years while the demand for natural and organic products has risen. Companies strive to optimise resources and reduce the ecological footprint caused by their production.

The fact that European institutions have dedicated resources to this technology is a clear sign that this process has its advantages. In 2010, a European project for environmental innovation has explored the possibility to replace the adhesive labels on fresh produce with laser markings directly on the surface of the produce.

This technique focuses mainly on the labeling of fruit and vegetables but isnโ€™t its only application. Aged cheeses can easily be marked by laser. In a recent article, we have discussed how laser systems can be used to engrave cheese wheels with identifying signs.

Another type of application mentioned in this blog is the laser impression of codes on eggshells. Tracing codes, expiry dates and laying dates are different pieces of information printed on eggshells. This data is fundamental to protect the health of consumers. Ink printing is the traditional method used. Laser impression efficiently replaces inkjet printing and makes it possible to avoid food products coming into contact with chemicals such as ink.

Watermelons after harvesting

Laser markings can be done on a wide range of elements. Generally, the best results can be obtained on produce with some type of skin, be it thick like the avocadoโ€™s, or thin like the tomatoโ€™s. Up to now, laser markings have been successfully carried out on different types of produce. Here is a partial list:

  • apple
  • avocado
  • banana
  • grape
  • lemon
  • orange
  • grapefruit
  • mandarin
  • peach
  • bell pepper
  • plum
  • tomato
  • watermelon
  • melon
  • chestnut

The advantages of laser labeling

Compared to traditional labeling techniques, direct labeling with laser markings provides a series of considerable advantages.

Speed

Laserโ€™s most renowned characteristic is speed of execution. A laser source integrated in a system with a conveyor belt can mark batches of around ten items a minute.

Precision and cleanliness

Thanks to numeric control, it is possible to etch characters, codes and images in high resolution on the surface of products without leaving any type of residue. This characteristic makes it easy to โ€˜printโ€™ QR codes, barcodes or complex logos.

Flexibility

Laser technologyโ€™s innovative characteristic is its versatility. A simple reprogramming of the laser control software is all that is needed during production to switch from one application to another.

Environmentally friendly

The use of many potentially polluting materials can become obsolete if replaced by laser marking. Plastic or paper labels, glue and ink can all be eliminated through the use of laser labeling. This would generate an important reduction of the ecological footprint. The products would then become less harmful for the environment or for the people that consume them.

Indelible

Laser markings are applied directly to the surface of the product and are therefore impossible to erase and difficult to counterfeit. This technique is perfect for products with symbols that guarantee their origin or quality.

Lemons on a conveyor belt ready for labeling
Laser labeling for food: the laser marking process

Laser labeling is under the wider umbrella of laser marking, a process with multiple fields of application. Laser marking consists in the removal of a thin layer of the materialโ€™s surface. This delayering is caused by a thermal process triggered by the laser beamโ€™s energy.

When the laser beam reaches the intended surface, it makes the temperature of the material rise until it causes its sublimation (the instant passage from solid state to gaseous state).

The removed material creates a well defined contrast between the untouched surface and the one marked by the laser beam. This process is renowned and used in many sectors on materials that arenโ€™t destined for food consumption.

Fruit and vegetables stocked in a warehouse

The technology used in laser food labeling

A laser system for food labeling is mostly identical to any other laser marking system. The fundamental components are:

  • a CO2 laser source
  • a scanning head
  • a software for numeric control and automation

The design for the machine layout will naturally depend on the type of plant, processes and product used. A company that distributes and commercialises apples will need a different configuration to a company that does laser markings on cured meats.

Nonetheless, both machines will need a laser source, a scanning head that moves and focuses the beam on the surface of the object and a software connected to the control unit that constitutes the interface between the user and the system.

Letโ€™s go over the characteristics these components need to efficiently carry out laser direct food labeling.

Laser food labeling: choosing the right laser source

Among the laser sources available on the market, CO2 lasers are the ones that show the best results when it comes to the absorption of organic material. These materials can efficiently absorb the infrared wavelength (10.6 micrometres) of a CO2 laser source because of their low thermal conductivity.

A laser source capable of keeping the laserโ€™s parametres stable is fundamental in laser marking applications. This will guarantee a result with high levels of precision. In order to achieve this, the laser medium must remain in optimal conditions.

Sadly, it isnโ€™t always possible. In the case of the CO2 laser, the medium is made of a gas mixture, of which the biggest part is carbon dioxide. Over time, the continuous leak of gas molecules makes the ones still present in the resonance cavity thin out. This causes a gradual degradation of the laser beamโ€™s parameters.

Mutations of the laser beam will show through a lowering of work quality. Maintenance from the producing company is usually the only way to go back to the laserโ€™s original parameters, but it means putting the production on hold and therefore increasing costs.

In order to avoid this inconvenience – which is typical of all CO2 lasers – El.En has created a autonomously rechargeable CO2 laser source. Because of this characteristic, El.Enโ€™s laser source can maintain the fundamental parameters of the laser at an optimal level.

Laser marking on produce doesnโ€™t require such a great power. Nonetheless, the power of the laser source will have a direct influence on the speed of production so it is something to consider.

Laser scanning head

Every laser marking application needs a scanning head to operate. We have already seen in previous articles how a laser source works and what use it has. A laser scanning headโ€™s function is to move the laser beam on a pre-established path that coincides with the processing of the goods.

A laser beam is a light ray that goes in a straight line until it reaches an obstacle of some kind. If a laser beam doesnโ€™t get deviated in some way, it cannot be used in production. The laser scanning headโ€™s job is to deviate the laser beam, making it follow a pre-established path.

The scanning head uses galvo mirrors to move the laser beam along the X and Y axes of a work area.

To function properly, the laser beam has to always be well focused on the surface of the processed product. A z-linear lense will increase and decrease the focal length of the lense and maintain the laser exactly where it needs to be.

The laser source and scanning head have to work in tandem. The laserโ€™s position, focus, power and the duration of the beam have to be decided according the requirements of the production.

The software and control unit are responsible for the coordination of all these devices. The software is the interface between the machine and the user. It translates the patterns needed for production into coordinates and parameters that the control unit sends to the scanning head and laser source.

A change of the softwareโ€™s parameters or the insertion of a new CAD file makes it very simple to engrave any type of information.

A red apples in a carboard box. The apple is marked with laser

A safe process

When considering the use of laser technology, some people fear it might alter the shelf life of their produce. The skin does protect from mold, bacteria and other agents that could damage its organoleptic properties making it unsafe for consumption.

In the case of cured meats or cheese, the risk is minimal since the external crust is very thick. The laser markings only go a few microns deep and are much less invasive than the ones done with traditional methods such as firebranding.

Things could have become more problematic with fresh produce, especially fruits and vegetables with a very thin skin like tomatoes or grapes. The fear was that removing a layer of skin (however thin) would cause dehydration and various types of contamination.

In reality, many studies have shown that laser marking only touches the surface of the product and doesnโ€™t provoke any alterations. The protective function of the skin isnโ€™t compromised and the shelf life remains the same.

The organoleptic properties also remain unaltered and we can positively say that laser labeling doesnโ€™t alter the flavour of produce in any way.

A world to explore

Laser marking for food products is a new world just waiting to be explored. Each product has different qualities and the parameters used should change accordingly. It is therefore fundamental to study a tailor made solution with the help of a laser producer.

Laser heat treating: focus on a surface processing technique

bobine-acciaio

In this article we will focus on one of CO2 lasersโ€™ applications: laser heat treating of metals.

This type of treatment refers to the use of a laser as a heat source to be applied on a metal surface in order to make it more resistant to wear and mechanical fatigue.

Rolls of laminated steel in a plant

There are several metals this operation can be applied to and results vary according to the type of metal or metal alloy. Laser heat treatment is used most on steel. This alloy is ideal for this type of treatment because of its carbon content and versatility.

Laser heat treatment can actually be divided into 3 diffferent types of processes: laser transformation hardening, laser annealing and laser surface melting.

In this article we will cover the first of these applications since it is the most widespread.

The way this process works

As opposed to traditional heat treating processes, lasers can be controlled with extreme precision. This makes it possible to contain the area and the depth of the layer that will undergo the heat treatment.

This characteristic is very useful in the processing of components subjected to mechanical or thermal stress such as, for example, cogs and mechanical components in general or work-related tools.

Steel gears: laser heat treating can be used to improve strength and reduce wear

One of the most widespread applications on steel is the hardening process. It is caused by the transformation of the atomic structure of a layer of steel. More specifically, laser energy is applied to the surface followed by a rapid cooling. This causes a uniform diffusion of the carbon atoms which makes the surface more resistant to wear and mechanical stress.

Stacks of laminated steel

Here is a partial list of metals on which the process can be applied:

  • low-carbon steel (up to 0.30%)
  • Medium and high carbon steel (up to 0.80%)
  • Various types of steel alloy

As previously stated, the final results of the process are highly variable and, depending on the type of material, can either increase a metalโ€™s resistance or pliability, or oppositely increase its ductility.

Before starting the process, it is therefore fundamental to analyse the metalโ€™s content and understand the final use of the produced object.

Send us a message with your requirements and we will help you find the right laser solution for you.

Modified atmosphere packaging through laser technology

Stunning young woman doing groceries

Modified atmosphere packaging, follows unique dynamics that you do not find in regular packaging supplies. It requires a precise regulation of parameters such as gas mixture and gas exchanges. It must take into account the fact that fresh products continue to exchange gases even after being put into the package. Laser technology is perfect tool to control those parameters through the manufacturing micro perforated packaging.

The domain of flexible packaging

Plastics polymers are used a lot in the food packaging industry, most successfully for fresh produce. Their versatilityย and resistance to chemical agents make them perfect for this type of application.

Their high capacity for transpiration makes them ideal for fresh produce. Every material, has its own natural traspirability that is its permeability to different types of gas molecules, particularly oxygen, carbon dioxide and water vapour.

Strawberries in plastic bag

This particular characteristic is fundamental for the conservation of fresh produce. The metabolic processes aren’t interrupted once the produce is picked. Processes such as cellular respiration and maturing, continue even after the produce has been packaged. If not appropriately counteracted, these processes can be responsible for a fast deterioration of the product. This is the reason why one of the biggest challenges of the fresh food industry is to slow down the metabolic processes that make the product unfit for consumption.

Packaging technology has found different solutions to circumvent the problem of produce deterioration. Disinfecting treatments, both chemical and mechanical or antifungal, go hand in hand with protective barriers such as plastic film.

Vegetables at a supermarket

Great progress has been made after the introduction of produce packaging in controlled atmosphere. This process takes advantage of the high transpirability of plastic film. The driving principle is to find the right balance between the gases within the packaging in order to counteract the deterioration process. Because every type of fresh produce has different metabolic processes going on, it is fundamental to choose the appropriate type of film that allows the best exchange of gas between the inside of the packaging and the outside.

Unfortunately, many films donโ€™t enable the right relationship between the gas entering and exiting the packaged product. What can be done, then? Laser microperforation can solve the problem. It makes it possible to make microscopic holes on the surface of the plastic film. Depending on the size of the perforations (that can range between 50 to 200 micrometers), it becomes possible to control the gases that go in and out and therefore maintain the right balance between gas and humidity within the packaging.

Vegetables at a supermarket

The advantage of this type of process is that it is easily integrable in a controlled atmosphere produce packaging plant. Let us imagine a company that deals with different types of produce. Each one needs to be packaged according its own specificities. The packaging has to be tailored to each product in order to have the right balance of gas inside the packaging. Laser technology allows for the optimisation of the entire production cycle. Each type of produce can be packaged without any change of machinery; a simple reprogramming of the laser control software is all that is needed.

Cardboard and CO2 laser

It is now a fact: the current pandemic has led to an explosion in online shopping and home deliveries. Contagion risks have led people to reduce any situation that include physical contact. Shopping activities have moved online for all types of goods, including basic necessities. Online shopping seems to be an increasingly common behaviour.

Forward-thinking companies have viewed these changing social trends as an opportunity to experiment with new and more advanced forms of packaging. They cater both to the new needs of home shoppers and the ones of companies that want personalised forms of packaging that better protect their goods. There is also a strong need for eco-sustainable packaging that uses fewer resources.

Laser technology has made all these things possible.

Laser manufacturing of cardboard boxes

The paper industry has now been using laser technology for several years. The CO2 laser offers undoubted advantages to its production processes. It can be integrated into fully digital, fast and flexible production processes, which allow cardboardโ€™s technical and material characteristics to be exploited to their fullest.

Cardboard is an ideal packaging material. It is inexpensive and light and can be processed into many shapes to create boxes and packaging to suit all kinds of needs. And what’s more interesting, laser cutting corrugated cardboad gives stunning outcomes.

The introduction of digital fabrication has made it possible to considerably expand the range of packaging products. Laser makes product customisation both economical and advantageous. The fact that it is no longer necessary to change tools to create different types of products has encouraged innovation, and the experimentation of new formats. Customisations (products made specifically to cater to a certain need) are now achievable at lower costs.

Until recently, companies that wanted to send or package their products had little choice. They had to rely on the box formats offered on the market. Box manufacturers dictated the law and only offered standard shapes and sizes. If a company needed a box shaped in a particular way or with an easy opening, it was limited to what the market had to offer.

Creating boxes and packaging with custom features was not cost-effective for manufacturers or customers, unless the number of produced pieces justified the investment in production means. For customers, the only way to obtain customised packaging at a competitive price was to secure large quantities of orders. This is not always possible, particularly for small and medium-sized companies.

The use of lasers has brought about a real revolution in the way paper products are manufactured.

The production process of cardboard boxes is based on two fundamental operations, cutting and engraving, which are at the basis for all subsequent processes. Cutting separates the shape of the box from the cardboard sheet. Engraving creates folding lines on the box or devices for easy opening, such as tear-off systems. Folding the box along the cutting lines and gluing the flaps together produces the finished product, i.e. the box.

The advantages of lasers

The advantages of laser cutting are many. The laser allows these same processes to be carried out with greater speed and precision, making the production process much more flexible.

On materials such as paper and cardboard, the laser cutting process is instantaneous. The laser immediately vaporises the paper along the cutting line, resulting in precise, clean cut edges. Laser cuts need no further finishing.

Precision is ensured by the fact that the laser is a non-contact process. This makes it possible to make cuts along particularly intricate paths even at very small sizes.

But laser technology isnโ€™t only useful for traditional machining operations such as cutting and creasing. It can also perform tasks that traditional tools canโ€™t.

Laser Marking is one of these processes. In marking, the laser does not perform cutting or engraving, but merely modifies the surface layers of the material, which results in the blackening of the laser-processed parts. This technique turns the laser into a real digital printer that engraves marks directly on the surface of the material. In this way, all kinds of marks can be engraved, from logistical information like QR codes, barcodes and alphanumeric codes to actual images like company logos.

This gives the production system enormous flexibility: the same laser system can perform all these processes, even on a small number of parts. Cardboard packaging manufacturers can now offer their customers a lot more choice and create customised boxes, even in smaller quantities.

Contact us

Cardboard box manufacturers agree that the CO2 laser is an invaluable tool. It makes it possible to carry out work that cannot be done with traditional methods such as die-cutting. If you are a cardboard box manufacturer and are interested in a laser production system, please contact us. Our technicians will be happy to study the most suitable laser solution for your needs.

Galvo heads for laser: focus on a powerful tool

The laser scanning heads are a fundamental component of the galvo systems for laser cutting and marking. These devices deflect the laser beam coming from the source and move it along the X and Y axes according to the operation required.

A mirror galvanometer and a z-linear optic inside a Galvo Scanning Head El.En. GioScan 1735

The components of a galvo head for laser

A scanning head is made of different components.

Galvo mirrors

El.En.'s complete range of galvo mirrors

Mirrors mounted on galvanometric rotary motors deflect the laser beam. These motors transform electrical voltage into angular movement.

The mirrors, mounted perpendicularly on the engines, move the laser beam along the X and Y axes according to the input received from the motor.

The big advantage of these devices is that they can reach a very high acceleration and speed of movement.

The size of the mirror depends on the laser beam. As the diameter and the power of the beam increase so must the diameter of the mirror. The same size in turn influences the acceleration and speed of the engineโ€™s angular movement. The smaller mirrors reach higher accelerations than the larger mirrors.

In the range of El.En.’s products there are galvanometric mirrors for different applications. Find out more about our complete 2-axis CO2 laser galvanometer mirror line on our website.

Z-linear optics

El.En.'s z-linear optics

Galvo mirrors are not the only components of a scanning head. The z-linear lens, which focuses the laser on the work surface, has an important role to play too.

To focus the laser beam and get it to work optimally, the focal length of the lens must vary based on the distance between the scanning head and the point it needs to reach on the surface.

The z-linear lens changes the focal length in real time and maintains the laser beam in focus regardless of its distance from the workpiece.

The control software

The control software makes sure that all the moving parts of the scanning head stay coordinated.

It transforms a vector file (the place where the work to be performed is described), into a path for the laser beam. The control software makes the galvo head and the laser source work together to achieve the desired result.

What processing can be performed with a laser galvo head?

As previously mentioned, the laser galvo heads are mainly used for cutting and laser marking.

Laser galvo cutting

Galvo heads make it possible to reach high processing speeds for cutting applications. Galvo heads are perfect for the processing of thin materials such as paper, cardboard and plastic film.

The head can cut out any shape quickly.

Some of the industries that benefit most from the use of galvanometric motors are the adhesive label sector that use kiss-cutting applications and the packaging industry that uses galvo-laser applications to make products with advanced features.

Galvo laser marking

A sheet of fabric engraved with galvo-laser marking

The main marking applications include the marking of various types of alphanumeric codes, such as barcodes and QR codes, and the engraving of ornamental motifs for decoration.

Laser marking can be performed on different materials such as thermoplastic polymers, wood, fabrics, leather, metals, glass.

In the case of transparent materials it is also possible to perform the impression of three-dimensional figures inside the object.

The advantages of laser galvo heads

Laser applications get many advantages from the use of galvo heads:

  • Speed รขโ‚ฌโ€นรขโ‚ฌโ€น- The galvanometric motors reach very high angular speeds. This means that the laser beam moves over the surface of the workpiece with speeds reaching tens of centimeters per second. Thanks to this the productivity of a laser galvo system is very high.
  • Integration – Precisely because of this characteristic, galvo laser systems are suitable for integration into larger production flows. A laser galvo system consisting of a scanning head and a laser source performs best when inserted into automated processes. Furthermore, it is compact enough to be easily added to pre-existing systems, giving it an important upgrade without major changes.
  • Quality – The laser galvo systems guarantee high quality and detailed results. In marking applications, the scanning head gives the possibility to create a wide range of effects, including the reproduction of a photograph on a surface.

One device, many tools

Scanning heads are a key tool in laser material processing applications. They transform a single beam of polarized light into an instrument with many applications.

To choose the scanning head that is most compatible with the application you need, request the help of an expert. Get in touch with us: our team at El.En. will be happy to help you find the most suitable laser scanning head for your applications.

Laser marking of identification documents

Marcatura laser documenti identificativi

Governments and organizations are constantly seeking solutions to make identification documents secure and tamper-proof. Cost-effective productions are key because in most cases security requirements combine with the need to maintain low costs.

Until not so long ago, all identification documents were made of cheap and readily available materials such as paper or cardboard. The documentโ€™s information was printed in ink or handwritten. Of course, not just any paper was used. In order to guarantee the originality of the document and combat counterfeiting, the paper was made using special treatments. Holograms, watermarks, or drawings were applied to the paper to make it as difficult as possible to falsify.

However, these products were not 100% safe since they could still at times be forged. Both the types of paper and the inks could be modified in such a way as to deceive even the most expert eye. This is the reason why the search for forgery-proof solutions has never ceased.

One of the solutions found was the laser marking of documents. The application consists of marking information directly on the material using the laser beam. The interaction between the laser and the material changes the surface layer causing a transformation that produces a mark. This mark is therefore not applied to the material but is an integral part of it. This technique guarantees that any successive modification to the document would result in irreparable damage that would highlight the counterfeit.

Laser marking can be used both on security paper – and on paper in general – but also on new-generation plastic identity documents.

Various objects such as ID cards, passports, credit cards, passes, or even hospital wristbands can be made using laser marking.

Given their identification function, these documents must have very precise functional characteristics:

  • the sign must be indelible and resistant to wear and tear.
  • the document must be difficult to forge or tamper with.
  • there canโ€™t be any defects
  • all documents must be identical

The marking process makes it possible to meet all these requirements and therefore satisfy the most stringent international safety requirements. The marking becomes an integral part of the material and cannot be removed. It is virtually impossible to forge a laser marked document unless you use the same tools and materials as the original document.

The laser marking process, like all laser processes, is computer controlled and therefore has a high repeatability and accuracy index. Once the process has been defined, the possibility of error is 0, and machining operations are carried out repeatedly with the same level of quality.

Laser marking lends itself to numerous applications. You can mark alphanumeric identification codes but also barcodes, QR codes, and even greyscale photos.

Laser allows you to add special security features such as microtext, variable images, i.e. images that change depending on the angle.

How the marking process works

It is a well-known fact that laser marking can be performed on various types of material. The best result is obtained on plastic materials such as polycarbonate and paper.

The marking on plastics is done by chemical degradation. The energy transferred by the laser carries out instantaneous transformations at the molecular level. The transformations change the visual appearance of the material by creating a dark-colored mark.

Laser marking also works on multi-layered documents. The laser can even reach a transparent layer by setting a specific wavelength. Marking can, therefore, be done at deeper levels and ensure that the mark is protected by a transparent surface layer and thus more resistant.

The possibilities go even further. Deeper marking with a tactile effect can be created through laser engraving techniques.

Laser engraving acts at a deeper level than laser marking and subjects the material to wider and more radical transformations. The mark made by engraving doesnโ€™t only have visual characteristics but also tactile ones. The combination of marking and engraving makes the ID much safer.

The laser marking process allows for results that cannot be obtained with other machining tools. Therefore it lends itself to the most advanced processes. In a world increasingly connected, having forgery-proof documents is more and more necessary. If you have such an application in mind contact us , we will help you make it happen.

Laser marking and engraving on fabric

Designing clothes | El.En. co2 laser

Laser engraving and marking for fabric are some of the innovative technologies that have taken hold in the fashion and interior design sector. Indeed, their introduction has given a sector that usually relies on unchanging production processes, the impetus to experiment.

Laser marking and engraving processes are fast, accurate and flexible. These characteristics make them perfectly compatible with production processes and explain why their use has spread so widely.

The introduction of laser has made it possible to significantly reduce the environmental impact of this industrial of the fashion industry, which is one of the most polluting. The production cycle of fabrics, from production to finishing, involves the consumption of considerable quantities of water, energy and chemicals.

Laser technology has therefore also established itself as an alternative production tool, capable of replacing all traditional processes with lower costs for the company and above all for the environment and with greater benefits for the end user.

Marking or engraving? The difference between the two processes

In the textile sector, lasers are used throughout the production chain, from cutting to finishing and decorating fabrics. The marking and engraving applications are mainly used in those parts of the production process.

Both applications use the laser as an energy source to remove a layer of material of varying thickness. Depending on the amount of energy transferred by the laser to the material, the layer of material removed is more or less deep and the transformations made to the material are different. The difference between marking and laser engraving lies precisely in these differences.

We speak of laser marking when the processing involves the materialโ€™s most superficial layer and its transformation is not radical. Oppositely, we talk about laser engraving, when the laser beam removes a consistent layer of material. The engraved mark is deeper and perceptible to the touch.

Given these differences, laser marking and engraving results can differ according to the chosen type of application or material.

Based on all the aforementioned information, laser marking and engraving can suit numerous applications. Laser is a very flexible tool that adapts to all types of applications.

In general, we can say that laser marking and engraving applications on fabric fall into one of these two areas: the decoration or the application of various types of information on the materialโ€™s surface.

Laser marking and engraving for fabric decoration

Laser decorations allow designers to fully express their creativity. They can create a wide range of decorative effects and details on fabrics by using marking or laser engraving. These can range from a simple geometric pattern to the transposition of images in grayscale, all the way to the creation of decorative details with a three-dimensional effect.

The decoration of denim fabric is a perfect example of how this field of application has become popular in the clothing industry. The laser marking of demin has revolutionized the way this fabric is processed. Traditionally the denim finishing process involved various steps such as washes, sandblasting and abrasion. These processes were used to give a particular look to the jeans, a specific shade or a worn look to the garment through cuts and abrasions. The problem with these processes is that they are extremely polluting, involve a large consumption of resources and have a significant negative environmental impact.

Denim laser finishing makes it possible to significantly save on product manufacturing times, optimize the production process, perfectly replicate the various types of denim washes, and create any detail with great flexibility. All these results can be obtained through the laserโ€™s transfer of energy on the materialโ€™s surface rather than through the previously mentioned consumption of resources.

Laser marking and engraving to communicate information

In a world where automation is becoming increasingly popular, the application of information on materials is an increasingly requested process. Laser marking and engraving can be used to apply barcodes, alphanumeric information, information on the characteristics of the product and its maintenance.

This information can serve different purposes. For example, imagine a manufacturer of fabrics destined for the semi-finished product market. By means of laser marking, he can automatically imprint information such as production batches and identification codes directly on the fabric.

The advantage of this type of application is that the information engraved or marked with the laser is indelible, resistant to wear and counterfeiting. The manufacturer can save on some production costs, and when it comes to logistics and traceability, have a fully automated production process. The product buyer also has the guarantee that important information applied to the fabric wonโ€™t be damaged by time or wear.

Fabrics that can be laser marked / engraved

All categories of fabrics can be laser marked or engraved. However, some of them are better suited to these processes. Below is a brief review of the fabrics on which laser application can be performed very easily:

  • Synthetic fabrics. Synthetic fabrics are among those that are best suited to laser marking / engraving processes. These are materials made from thermoplastic polymer fibers, such as polyester. These materials respond very well to laser processing and therefore give optimal results.
  • Natural fabrics.Cotton is the natural fiber that is best suited to laser marking / engraving processes. To mark cotton you need to choose fabrics with a fairly compact texture.
  • Leather and faux leatherย . Laser marking can be applied to both natural and synthetic leather. Not only can laser technology be used to perform traditional processes, it can also create effects that could not be obtained with traditional tools.

How a laser system for marking fabrics is made

The components of a fabric laser marking / engraving system depend on the type of application needed. However, some basic components needed for typical engraving and marking applications are always necessary: a laser source and a scanning head.

The laser source is the device that generates the beam that performs the process. Their versatility when it comes to different materials makes CO2 sources the most suitable for these types of processing. Deciding how powerful the laser source should be is directly proportional to the manufacturing speed required. The more powerful the laser source is, the more instantaneous the execution.

The scanning head and attached software system can make any type of pattern in a very short time. They are therefore perfect for this type of processing, even if performed at high speeds.

An application with infinite possibilities

The laser marking and engraving of fabrics will increasingly take center stage in the fashion industry. The advantages they offer in terms of flexibility, accuracy and speed are enormous. Moreover, their greatest advantage for an industrial sector that makes innovation and design its essential strength is their endless application options.

Are you in need of a laser engraving or marking application? Contact us and we will happily put our extensive experience at your service to devise the ideal solution for your needs.

Laser cutting polypropylene

Plastic is one of the best suited materials for CO2 laser cutting. Polymer laser cutting is a very efficient and effective industrial process. Among all the plastic polymers that can be processedย by CO2 laser,ย polyethylene is one of the first in terms of frequency of use. Polypropylene has an excellent laser energy absorption capacity which makes it suitable for all types of applications ranging from drilling to welding.

Polypropylene: characteristics and uses

Polypropylene is a thermoplastic polymer obtained from the polymerization of propylene.Its main feature is that the molecules making up the polymer can be arranged in an ordered or random way. In the first case, polypropylene takes on the characteristics of an isotactic polymer.

Polypropylene beads - El.En. - CO2 Laser sources

This configuration is the most commonly used commercially since it gives the material excellent chemical, physical and mechanical characteristics.

Polypropylene has a high heat resistance (greater than polyethylene), good elasticity, rigidity and the ability to absorb shocks without breaking. It also has a low density, (which makes it light), a high insulating power and good resistance to oxidizing and chemical agents.

Finally, polypropylene can be processed in a variety of forms: injection molding, thermoforming, extrusion for the creation of textile fibers.

Given these characteristics, polypropylene has found a myriad of applications in every field. One can argue that there is no industrial sector that does not make use of polypropylene in some shape or form.

Here is a list of the objects that are most often made with this material:

  • Packaging, labels and containers
  • Kitchen items such as dishes and food containers
  • Sportswear
  • Components for automobiles
  • Bags,
  • Sanitary objects
  • Electronic object components

Can you cut polypropylene with laser?

Yes, of course. Polypropylene laser cutting is a very efficient process since this polymer absorbs the infrared wavelength of CO2 laserย very efficiently. With laser, making cuts or drilling holes on polypropylene is very easy.

On a macroscopic level, laser works as a cutting blade. The cut has a smooth and well-finished straight edge with no presence of burns or charring. Burr formation or cutting irregularities due to the presence of residues are also very limited. The high energies produced by laser not only melt the plastic, but makes it evaporate by sublimation.

The quality of the cut is directly influenced by the laser power, the cutting speed and the thickness of the material. In general, a medium-power CO2 laser source is sufficient to perform most of the processes needed in polypropylene applications.

Furthermore, the quality level is also influenced by the wavelength used. For this type of material our team of El.EN engineers have devised a specific laser source: BLADE RF333P.

This tool is very well suited to label cutting applications which use the kiss cutting process. A fundamental characteristic of this process is the variation in wavelength absorption related to the type of plastic film used.

In addition to simple cutting, polypropylene also lends itself well to laser kiss cutting operations, a process used mostly in adhesive production processes. Drilling polypropylene is also a suitable application, especially useful in the fabrication of plastic bags for modified atmosphere packaging.

Implementing a laser system for polypropylene cutting

The process of laser cutting polypropylene has many advantages: it allows you to perform complex, precision machining with great speed. It is also a very flexible system, which lends itself to numerous applications.

In addition to cutting, polypropylene responds very well to other laser processes, especially drilling (perforation), marking and engraving, welding. The same laser source can carry out all these processes.

If you work with polypropylene and would like to shift to CO2 laser technology, contact us. We would be happy to help you find the most suitable laser solution for your needs.

Laser cutting PTFE (teflon)

Can youย laser cut PTFE (Teflon)? The answer is yes. PTFE can be successfully laser cut,ย marked 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 Teflonยฎ or Algoflonยฎ 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 laserโ€™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 drillingย 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 doesnโ€™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 machineโ€™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.ย 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.