Laser cutting of wood-based products is one of the most important applications of CO2 lasers. Today, laser is a powerful, flexible and reliable tool: it made it possible to overcome the limits imposed by the traditional methods of machining wood based materials.

The advantages of laser production are many. Here’s a few:

• it tremendously speeded up operations such as cutting, drilling or marking on various materials
• it allowed to extend the use of materials such as engineered wood products for the production of parts and components
• it allowed operations that couldn’t be achieved with traditional, mechanical, applications, due to the limits of either the material and the machines

It’s no coincidence that one of the first commercial applications of CO2 lasers was the cutting of plywood die boards for the packaging industry. This sector in particular has really benefitted from the advent of laser-based production methods. The reason is that CO2 lasers are perfect for machining wood, paper, cardboard and similar products, largely used by the packaging industry. CO2 laser cutting opened up a new range of possibilities for this industry.

But how does the CO2 laser cutting process work?

CO2 laser cutting, a precision technology

The laser cutting process in itself does not involve any mechanical force. It relies upon the physical and chemical processes that take place when a focused laser beam hits the surface of a material.

A high intensity beam of light is generated by a laser source, like one of our BLADE RF Self Refilling family. This laser beam is then reflected by a system of mirrors, until it passes through a lens which focuses the beam down to a small spot onto the surface.

This means that, in a single spot a fraction of a millimeter wide, is concentrated all the energy generated by the laser. The spot thus reachers a great energy density which causes the immediate sublimation of the material surface touched by the laser. In this way the  desired cut is produced.

Despite the highest energies involved in this operation, laser cutting of wood is a very safe process. The entire operation is controlled by a computer, resulting in great accuracy. The cutting kerf is very narrow and precise and no damage is possible, provided that the laser is properly set.

The cuts obtained in such manner have some unquestionable qualities:

precision: the CO2 laser provides accurate cuts. The energy is focused precisely on the spot indicated by a software. Since the dimensions of this point are very small, working tolerances are very tight, allowing very complex profiling paths

smooth edges: the edges obtained from CO2 laser cutting don’t need further finish because they all have a polished appearance

Reduced costs: the laser cutting of wood results in the absence of any sawdust, shavings or other leftovers. This, combined with the lack of blades or other mechanical tools, create a very quiet working environment

Laser cutting of wood can be achieved on different types of woods. The results can vary a lot, depending on parameters such as the type of wood, its density and resin content and, of course, the thickness of the panel that is going to be cut.

Laser and MDF: an example of success in the industry of packaging

The best results of CO2 laser cutting on wooden products are achieved on the so called engineered woods. Those derivatives of wood include products such as plywoods, laminated woods and medium-density fibreboard or MDF.

Not too long ago, the operations that could be achieved on such materials were scarce, due to intrinsic properties of them. All engineered wood are composite materials, made from fibers of chips of wood pressed together. This features made them unsuitable for accurate machining operations, especially at a small scale. That’s why they’ve long been overlooked as engineering material.

CO2 laser cutting made those materials suitable for a new set of applications. An example of this can be seen in the packaging industry.

The construction of packaging products is a very challenging business. A good packaging has to be tough, light and attractive for the customers. But how to achieve all those contrasting needs? Thanks to CO2 laser cutting, the packaging industry introduced new materials for the creation and design of packaging. This is the case of boxes, crates and cases made from laser cut MDF panels.

MDF provides the same toughness and performance of solid wood but at a lower cost. Those characteristic make MDF a perfect material for the design and engineering of packaging products like boxes, crates and cases of various kind. A CO2 laser is able to easily cut the panel in MDF in all desired shapes and dimensions. It is possible, for instance, to produce the various components to assemble boxes and crates. In this way it becomes easier to create containers of every kind and dimensions, that can be used to protect delicate products like fruit from the risks of damage during shipping and transportation.

This is only one example of the many possible applications of CO2 laser cutting for wood. The introduction of such a technology affected many industrial sectors anche the packaging industry is only one of them.

It might also interest you: CO2 Laser: a new technology for the fabrication of corrugated fiberboard and cardboard

Laser engraving is one of the many applications of CO2 lasers. This process uses the energy delivered by the laser beam to mark the surface of a material. In the last decades, laser engraving proved to be an effective and efficient tool for the manufacturing applications, especially for the fashion and decorating industry.

The variety of materials that can be engraved is wide and includes either natural and synthetic materials as well as metals. Wood, paper, cardboard, plastic and plastic films or rubber are very well suitable for CO2 laser processing. Those materials absorb very well the specific wavelength of CO2 lasers. This means a greater energetic efficiency of CO2 laser light.

Thanks to this feature, CO2 lasers are particularly suitable to sectors like the fashion industry. This trade largely handles organic materials like natural fiber tissues or leather: CO2 laser engraving proved to be an economically efficient and powerful tool for the decoration of fashion goods and accessories.

The decoration of leather, both natural and synthetic, is one of the branches that have benefitted the most from the introduction of laser as a processing tool.

Leather and CO2 laser engraving

The traditional approaches to leather crafting involves the use of hand tools or physico-chemical processes. Engraving the surface of a piece of leather is a matter of craftsmanship and perseverance. Those methods are not suitable for today’s needs of mass production. They are very slow and time-consuming: leather is a flexible but tough material and thus operations such as cutting or engraving take a lot of effort, expertise and time to be carried out properly.

The introduction of laser has significantly improved those drawbacks of traditional leather decorating techniques.

CO2 laser engraving of leather is based on the energy developed by a CO2 laser focused on the surface of the material. The high density thus obtained, produces the immediate sublimation of a shallow layer of material, leaving a mark on the surface.

Those marks have some great qualities: they are permanent, sharp and very accurate. They are also immune to wearing, scratching or fading because of light or mechanical aggression.

As all laser applications, the whole process is controlled by a software. A typical laser engraving leather machine is composed of three components:

• a CO2 laser source. El.En. Blade RF Self Refilling is a perfect example
• a laser scanning head. It can be boiled down to three main components: a X axis galvanometer, a Y axis galvanometer and a z axis actuator that dynamically adjusts the focal length of a lens. The purpose of the scanning head is to deflect the CO2 laser beam so as to to keep it always focused on the working area
• a software. It translates the design developed by the operator into the a that the laser beam will follow.

Thus it is possible to create any model on the software and then transfer it onto the surface.

The advantages of CO2 laser engraving on leather

With the help of the software, it becomes possible to accurately control parameters such as the speed, power and intensity of the CO2 laser beam. Depending on those parameters, laser engraving allows a virtually infinite variety of effects on leather.

The advantages of such a feature are remarkable for the general leather engraving process:

• A CO2 laser system is flexible:it is possible to rapidly develop and test new design prototypes and try out textures, patterns and other effects
• The use of nesting software allows to automatically find the most efficient laser engraving pattern, thus minimizing the production of scraps and wasted material;
• The controlling software is also able to optimize the efficiency of the CO2 laser machine. For instance, by identifying shared contours that can be cut at once;
• It is possible to reproduce the same design over and over without minimal or no differences, resulting in constant quality over the time.

Those aspects of CO2 lasers make them an attractive tool for the producers of leather goods, especially for those operating in the fashion and decorating industry. The laser is a flexible and efficient device. Its possibilities are infinite, all to be explored and tested. It allows innovation and originality, freeing the designer from the constraints of traditional leather engraving techniques. And, undoubtedly, this is a considerable benefit that CO2 lasers can offer to the fashion industry, constantly driven by innovation and always in search of original designs.

In the last few years, laser-based processes have found application in nearly every sector. Practically every machining operation, that has traditionally been performed by mechanical tools, finds a laser equivalent. Lasers can currently cut, weld, drill, heat treat, kiss cut a very wide range of materials.

For the industrial sector, CO2 laser sources are widely adopted. The features of their laser beam make them suitable for a great variety of manufacturing applications and materials. A CO₂ laser is definitely what you need if you are considering switching to a laser based production process.

But what are the advantages of adopting a laser system and in particular a CO2 laser? How can it improve the productivity of your lines? Let’s make this clear using the example of laser cutting.

1. You won’t need strong fixturing

Since CO2 laser cutting is a non-contact process, you need no strong fixturing to keep your material centered on the working area, as in conventional machining. In CO2 laser based process, no mechanical forces are implied: the laser head will deliver the laser beam where required.

This feature will speed up the transition from part to part or between sheets of different materials through a production run. In a small amount of time you will be able to cope with different design patterns for both additive manufacturing or fabrication.

2. Cutting flexible materials will be a joke

The absence of touching parts and strong fixturing speeds up the cutting operations of flimsy materials like paper or plastic film. When performing a cutting procedure, a laser beam is as sharp as a scalpel. Forget the fear of accidental distortions or cracks: a laser beam won’t push on objects with which they come in contact. Hence a CO2 laser will be suitable for both soft and hard materials.

3. Computer is on your side

Computer numerical control (or CNC) will give you a complete control of essential parameters such as the kerf and direction of cut. Thanks to the narrow cutting kerf allowed by CNC CO2 laser cutting you will obtain the most intricate and beautiful design patterns.

4. Reduce the wastage of material

This means that you also will be able to make the most of your base material. It will be easy to optimize the arrangement of the figures to be cut out from the surface, so as to minimize the wastage of the base material and optimize your ressources.

5. A slight heat affected zone means that your material will be safe

Laser cutting processes like CO2 laser cutting use the energy and heat conveyed by the laser beam to cut through a material. You might think that such a process would damage material as delicate as paper, plastic film or cardboard. Actually, the heat affected zones are so small that laser cutting operations are perfectly suitable for heat sensitive materials.

6. Cutting operations will be done at the speed of light

A CO2 laser cutting system is very fast. It takes only a few instants to cut even the most intricate and arbitrary contours from a sheet of various materials.

7. Perfectly refined and uniform parts

Lasers are so precise that they cut through without leaving any imperfection. Your produced parts will be perfectly and completely refined and uniform.

8. Minimize tooling costs

A great advantage of CO2 laser cutting over mechanical machining is that there is virtually no tool wearing. A laser beam will always be a sharp cutting knife, producing clean, smooth, round edges. Needless to say, tooling costs will be dramatically reduced, especially in sectors that process very tool consuming materials (e.g. abrasive materials and sand paper production).

In conclusion, laser based machining processes are fast, reliable and cost effective tools for your production lines. They allows great flexibility and repeatibility of the process, ensuring small to no variations between the parts. Switching to a laser cutting system will dramatically improve your productivity rate and make your work more easy and fast.

Wood, paper, cardboard, plastic, PMMA. And also rubber, leather, metals, and ceramics: CO2 lasers can cut a great number of materials. For this reason, CO2 lasers have become the most widely diffused laser technology for laser material processing.

However, despite the wide use of the CO2 laser we receive a lot of questions on possible appications that can all be summed up by what materials can be cut by CO2 laser? In this article we answer to this question with a simple list of materials that can be easily cut with CO2 lasers (the links take to articles that examine each topic in depth): 

• Wood based materials
• Paper based materials
• Acrylic (PMMA) and other plastic polymers
• Leather and faux leather
• Natural and synthetic fabric
• Biologic materialAll industrial sectors that need to process these materials can thus use the laser CO2 for a faster, smoother, and more precise cutting process.

Fields of application

To go into the details, the following list displays the main applications of CO2 laser cutting, ordered by industry:

• Papermaking industry
• Cutting cardboard boxes
• Cutting paper and cardboard
• Stencil cut
• Decorations

• Woodworking industry
• The cutting of any kind, and thickness, of wood, especially Plywood and MDF
• Inlay fine wood
• Engravings of any kind

• Engravings and inlays
• Laser engraving and cutting methacrylate
• Laser engraving and cutting leather goods
• Laser engraving name and number plates
• Laser engraving and cutting textiles
• Laser engraving electronic components
• Laser engraving anodized aluminum and varnished metals. N.B.: the CO2 laser usually doesn’t cut metal but can label or mark them indelibly.
• Engraving of glass, marble, and stones
• Inlays on ivory

• Creation and Customization
• Laser cutting hollow punches
• Laser cutting for architectural models
• Laser cutting plastic, cardboard, or wooden displays.
• Contour and cut labels
• Personalizing gadgets
• Personalizing buttons
• Material machining for model making

The list above is just a short list of the many different materials that can be processed by the CO2 lasers: there are lots of other materials that can be cut with the CO2 laser. Research on the applications of the CO2 laser is still an ongoing process, of which experimentation plays an important role: only experimentation provides us with certainty about the possible applications. For this reason we invite you to contact us whereby the material you want to work is not presented in the above list. Together we will find you the solution that fits your needs!

Let’s continue exploring the applications of CO2 lasers. In this article we will be talking about acrylic and CO2 laser.

Acrylic, also known as PMMA or plexiglas is one of the plastic materials that can be laser processed with success. In particular, CO2 laser is the right to do the job.

What is acrylic and why it is so successful

Acylic was discovered in the 1920s. However, the material only really gained ground only after WWII as a cheap and effective replacement to glass. Easy to manufacture and process, rugged and flexible, acrylic has imposed itself as a successful material for a wide range of uses.

CO2 laser and acrylic

Acrylic is also known as PMMA. This acronym stands for Poly Methyl Methacrylate and refers to its chemical formula which includes atoms of carbon. For this reason acrylic materials responds very well to the wavelength of CO2 laser, which is 10.6 micrometers. At this wavelength, acrylic is opaque to CO2 laser, which is therefore absorbed very well by the material. This feature, coupled with low thermal conductivity and a relatively low sublimation point (300 °C), allows acrylic processing to be done quickly and easily. As a matter of fact, the fabrication of acrylic materis is one of the applications in which CO2 lasers give the best results.

Laser cutting acrylic

The main laser processing technique for acrylic is probably laser cutting. As se we have seen, the interaction between the laser and acrylic is very efficient. That means that when a CO2 lasers interacts with an acylic surface, the latter absorbs a large part of the energy conveyed by the laser, which is focused then on a tiny spot.

High energy on a very small surface means instantly vaporizing the material and as a result we obtain the cut. This process is called by sublimation of the material. Sublimation causes the material to evaporate and therefore does not create residues, making laser cutting an extremely clean process.

The end results of this process is extreme precision and quality. The cut has clean and smooth straight edges that don’t require further finishing.

The acrylic laser cutting process is also incredibly fast. Speed ​​is related to the thickness of the material and the power of the laser source. But whatever the thickness, the processing speed will be significantly higher than the mechanical cutting methods, even if it is a CNC method.

The possibilities of laser machining are endless and, ultimately, only limited by the designer’s imagination.

Do you need a laser cutting system?

At El.En. we have a long experience in producing laser systems for the fabrication of acrylic. We can design complete laser system or integrate our CO2 laser in existing laser. For whatever request or question you might have just contact us!

The fashion, decoration, and design sectors are generally very competitive. They require a continuous stream of products and models to be offered to the public. There is a constant search for new and original design which is capable of characterizing the designer, while at the same time being in the interest of the public. In fields like design, innovation mainly relies on the imagination of designers.

That is why introducing the CO2 laser as a decoration tool has been greeted with enthusiasm by the decoration industry. The laser allows remarkable flexibility and allows to overcome any limitation imposed by traditional decorative production processes. Especially in the ceramic tile industry the laser technology process has proved to be a great ressource. The introduction of the laser has allowed producers to deeply innovate the production processes, but has also allowed them to give space to the creativity of designers. Laser technology allows to reach quality standards that were previously unattainable, while at the same time saving ressources.

The CO2 laser decoration process of tiles is based on the removal of a superficial layer of the material. The system consists of 3 basic components:

• A CO2 laser source
• A scanning head
• Control software

The laser allows you to improve the quality of machining significantly. Thanks to the laser control software it is possible to obtain a level of control and detail on ceramic tiles surface which previously was deemed impossible using traditional decorative processes. Here are the main features of machining:

• Well-defined lines: The laser allows to obtain perfectly defined lines on the ceramics, unlike conventional mechanical methods.
• Very narrow angles: the tolerances made possible by lasers are very high. This means that even very complex designs can be easily realized.
• Almost photographic quality: By adjusting the laser parameters appropriately, such as power and speed, you can get a wide range of shades making the image surface almost photographic.

Another advantage of a laser based system is its versatility that made it possible to experiment and propose new prototypes very quickly. Manufacturing gets very easy thanks to laser technologies, a tool always at the forefront of innovation in design.

The change in consumer behavior has augmented the demand for ready-to-use food. This, in turn, has resulted in the demand for different packaging types. The food technology industry has developed along and adapted in concordance with these behavioral changes, offering increasingly advanced food packaging. Consumers no longer want to be confined to plastic bags or containers, but want packaging types that are practical in use, easy to open, and that don’t require the use of additional tools. On top of this, consumers demand packaging types that do not sacrifice the freshness of food, which is a current priority to the ever-demanding consumer of today. The shift in the packaging industry is easily visible by solely walking around in the local supermarket. From ready-to-use salad to instant noodles, packaging has changed. All of this has resulted in the need to make customized packaging.

The challenges of packaging are not trivial. Traditional methods of processing and finishing of cellulose and flexible packaging are less practical in today’s market. The market has shifted from a time where general packaging suited each product, to a market where each product requires its particular packaging type. Due to this shift, traditional packaging processes have become disadvantaged. Traditional packaging involves mechanical machining; tools for cutting, engraving, and imprinting are used for mass production. Due to this, the packaging quantity has to be augmented in order to cover costs. This traditional packaging process limits flexibility and adaptivity, solely serving the mass packaging market.

Today, however, the market is much more segmented and demanding. The winning producer is the one who is able to best adapt to consumer demands and provide real added value to their products. This is a real change of paradigm, made possible by the establishment of digital production processes.

The laser is the protagonist of this change. Laser Technologies have been established in recent years as an indispensable instrument in the processing industry of cellulose and plastic packaging. Agile, accurate, and reliable, the laser is a non-contact process that is based on software control to achieve maximum precision in machining.

Laser technology is incredibly versatile: not only provides it the possibility to perform work in a more efficient way, it also makes it possible to perform tasks that were not previously possible with traditional machining. The laser allows you to personalize packaging in any way preferred. These technologies have opened up new possibilities in the packaging world.

Let’s have a look at some of the possibilities offered by the laser.

Laser engraving

Laser engraving consists of engraving a layer of plastic material. This technique is ideal for making packaging with an “easy opening”. Easy opening bags are those where the opening is engraved: the consumer only has to pull slightly in order to open the packaging material. This processing would be very difficult to obtain and costly with traditional methods. Thanks to the laser control software it is possible to accurately set the laser parameters to obtain the desired cut depth.

Laser micro perforation

Laser micro perforation involves drilling micro holes in the plastic film. Micro perforation is used in food packaging utilizing controlled atmospheres. Laser micro perforation allows you to obtain holes of any desired size, thus enabling modified atmosphere packaging. The holes are perforated precisely in the preferred size, to ensure correct gas exchange between the inside and outside environment of the packaging, thus extending the durability and freshness of these products. Traditional methods of micro-perforation did not allow this process to be controlled accurately. Thanks to the laser, modified atmosphere packaging has been made possible, guaranteeing an expanded and improved product-lifespan.

Laser cut

Laser cutting is used to cut plastic materials from side to side. The laser cut is suitable for creating very precise details, even when cutting on small surfaces. Holes for filtering, plastic containers with special shapes or openings can be made easily and quickly thanks to laser cutting. Traditional cutting tools do not allow these complex or high precision cuts.

A flexible and easy-to-integrate tool

Laser features have revolutionized the way in which packaging is understood. Thanks to the laser, it is possible to adhere perfectly to customer requirements, providing products with real added value. These characteristics enable producers to tackle the most recent challenges in the industry.

All of this can be reached using minimum effort: to install Laser System El.En. it is not necessary to revolutionize existing lines. Our CO2 laser is compact and easily modulated for all your needs. The laser can be easily inserted into systems and adapted to the existing features. No mechanical system can ever be as fast as the laser. As a matter of fact, inserting a laser into a production line avoids bottlenecks that are often represented during the finishing process.

One of the characteristics of CO2 lasers is that it allows you to carry out processes which were impossible to perform beforehand, because of technical limitations in the past.

The CO2 laser has introduced new possibilities that have been exploited to meet market demands. One of these advantages is, for example, the laser micro perforation of plastic film. This technique has proven to be very useful for the packaging of fresh products before distributing them to mass retailers.

Micro perforated bags with laser for the packaging of fresh products

Laser microperforation is one of the newest methods to create micro holes in the packaging materials of products. To do this, the CO2 laser is used in pulsed mode. Unlike continuous mode, the pulsed mode sends high-intensity light flashes on the packaging material.

Laser micro perforation is particularly important for the packaging industry of fresh products. An increase in the demand of ready to consume fruit and vegetables, distributed via mass retailers, has led to the development of new strategies to ensure product freshness. Controlling storage temperature and modifying the atmospheric conditions within the packaging of products are the two most important factors for the quality of fresh products. The packaging thus has an important role in maintaining the freshness of the product, as it works as a regulator between the interior and exterior environment.

Laser micro perforation allows you to optimize the conservation of these products, through an improvement of the product packaging.

Objective: to improve the breathability of plastic bags

The packaging materials of fresh products in controlled atmosphere are often seen in the form of plastic bags. These bags allow optimal isolation of the products, and seal them perfectly from external contamination of molds or bacteria.

But there is a disadvantage: the breathability of these materials. Plastic film is a material that limits gas transmission with the exterior atmosphere. For a proper preservation of fresh products this is a significant disadvantage, as fresh products are subject to metabolic changes such as breathing, exchanging gases with the exterior atmosphere, and producing gas from chemical processes that take place within the fresh produce.

To improve the shelf life of a product, a continuous gas transmission between the interior and exterior atmosphere of the packaging is required. The levels of oxygen and carbon dioxide, play a big role in the conservation of the product. For this reason plastic bags must be perforated, in order to facilitate a proper gas flow between the internal and external environments. The amount of gas transmission required, however, differs from product to product. For this reason the perforation process must be properly adapted to the product needs. This aspect of adapting the perforation process, however, is difficult to achieve with traditional perforation methods.

Traditional micro perforation processes of plastic bags

Traditionally, the perforation of plastic bags is performed through two types of mechanical processes:

• Heated or unheated needles: the plastic film is perforated by needles applied with or without heat. This process, though inexpensive, is slow. In addition, the holes produced have a larger diameter and can let contaminants, such as bacteria and mold, in. It is therefore not suitable for contaminant-sensitive products.
• Electric discharge: packaging bags can also be perforated by means of electric discharge. The plastic film is passed through a high electrostatic voltage in which sparks are led through the packaging film to create micro holes. This process, even though faster than the previous one, is hard to manage. The hole parameters can not easily be checked. It is therefore unsuitable for those products that require precisely controlled gas transmission.

Laser Micro Perforation: accuracy in the service of the product

The machine that generates the best results in terms of micro perforating bags, turns out to be the CO2 laser. Micro perforation with the CO2 laser makes it possible to control the drilling process very accurately and obtain high quality results.

The CO2 laser is very well absorbed by most polymers and thermoplastics. The controlling software makes it possible to set the parameters to obtain holes of the required size and density, that let you create the optimum environment for gas transmission.

A laser micro perforation machine has the following advanta

Laser labeling of food is a recent innovation that makes it possible to reduce production waste by replacing traditional food labels with laser engraved labels. Laser marking of food is suitable for companies wanting to optimize their production process, saving resources and materials while also decreasing their ecological footprint. The possibilities are endless.

In fact, an increasing number of companies have realized that laser techniques are the key to process innovation. In a recent article we discussed the growing phenomena of natural branding, a process in which traditional food labels are replaced by the laser marking of the skin of food.

Fresh products such as fruits and vegetables can easily be marked through a laser scanning head, a low power CO2 laser source and a software that controls the process. This procedure of laser marking permits us to imprint logos, barcodes, and any type of information on different types of food without affecting their quality. The marking does not affect the organoleptic properties of the food – it is a “friendly process” as it only affects the most superficial layer of the skin of fresh products.

However, fruits and vegetables are not the only types of food that can be marked with the CO2 laser technology. Results have shown that even seasoned and semi-seasoned cheese and hams can be marked.

A case study: machine designed to mark seasoned and semi-seasoned cheese.

These seasoned and semi-seasoned products have always been marked through heat methods. Products are marked with their brand and codes that establishes the batch of production, identify the producer, allow to trace back the origin of the product. The easiest system to mark food is to use a metal to impress a brand by burning the surface of the product.

This traditional method, while being inexpensive, is incredibly slow and inflexible. In order to change the codes to be imprinted, a change in the marking tool is needed.

A more efficient way of imprinting information on food is to use the CO2 laser application. The laser allows to mark the surface of these products faster, with higher precision, and in a more secure way. In comparison to traditional ways of marking food, such as marking through means of heat, laser marking allows us to have an extremely precise process: it provides the possibility to adapt all parameters involved to suit the characteristics of the product to be marked. In this way the process of laser marking becomes the more precise way as it respects the unique characteristics of each product.

A system for marking the dairy products may consist of the following elements:

• Completely washable stainless steel structure
• Conveyer belt
• CO2 laser source
• High performance laser scanning head
• Controlling software

The functioning is semi-automated. The system involves the presence of an operator placing the products to be marked on the conveyer belt. The conveyer belt transports the products to the laser processing space, isolated from the outside with doors that can be opened for inspection and sanitation reasons. Here the laser scanning head, controlled by a software, guides the laser beam on the surface of the product, performing the marking within seconds. In a few minutes only, the operator is able to perform the same operation dozens of times.

The advantage of such a system is its flexibility. First of all, the machine is designed to be modular: each module can be replicated and adapted to the needs of the manufacturer. For example, you can install different laser sources for different applications.

Furthermore, the system allows you to change the information you want to mark very quickly. You just have to modify the parameters inserted in the control software to perform a different process.

What if producers and distributors of fruit and vegetables stop using sticky labels? It’s not phantasy but reality: with laser food labeling, labels can be written directly on the skin of a product by removing the superficial layers of the skin itself. An innovation beneficial for the environment and for the consumer. In this article we describe you this processing technique and we present you a case study where we describe how we created an automatic laser system for the labeling of apples. If you already know what natural branding is, you can jump to the case study.

First priority: reducing waste

Recent years have seen the development of a greater sensibility towards the environmental impact of the production processes. Manufacturers are trying to streamline the use of resources and materials, switching to greener ways of producing goods.

For the packaging sector this meant an overall reduction of the materials composing the packaging products: paperboard boxes, rolls of wrapping paper and plastic films are being supplanted by their biodegradable equivalents or they are simply being discarded.

Quite revealing of this trend is what happened to the most simple and traditional packaging product: labels.

CO2 laser labeling? That’s natural branding!

The phenomenon has been called “natural branding” and it especially concerns the packaging of fresh fruits and vegetables. Simply put, natural branding is to replace plain physical labels, sticked on the surface of fresh fruit and vegetables, with “natural” labels, obtained through laser marking.

This is only one of the many applications of CO2 lasers, a technology that demonstrates, again, to be a green process. In fact, producing a mark directly on the skin of produces results in reducing the consumption of materials such as paper and plastic and thus in a smaller environmental footprint of the packaging process. A CO2 laser let you engrave to engrave a lot of information: traceability codes, logo and brand of the producer, expiration dates. All this pieces of information were usually printed on traditional labels that were sticked on the surface of produces.

This laser labeling system is very advantageous for the whole packaging process and for the environment as well: a smaller energy consumption, the reduction of potentially polluting materials, a higher speed of execution. A perfect tool for all the manufacturers aiming at a greener production process.

But how can a CO2 laser engrave the surface of fresh fruit and vegetables?

Laser marking of food

Laser labeling of food is a special application of CO2 laser marking. In a previous article we have assessed the efficiency of laser marking on organic materials such as wood or leather. Even food can be marked without difficulty.

Broadly speaking, the process of laser marking relies on the high energy density delivered by a laser on the surface of a workpiece. It is that process that produces the desired marking on the surface.

An ordinary laser marking system is composed of three parts: a scanning head, a low power CO2 laser source and a computer equipped with the control software.

The scanning head contains three components: two galvo motors with two beryllium mirrors mounted on them; one linear actuator that dynamically adapt the focal length of a lens. The goal of this device is to deflect the laser beam and keep it always focused on the surface of the workpiece. Thanks to the laser scanning head the laser beam can be delivered on the entire surface of the workpiece.

Both the CO2 laser source and the scanning head are controlled by a software that, fed with the correct parameters, achieves the marking process of the desired design. In this way it is possible to control the speed, the position and the power of the laser beam, making it possible to obtain all types of images, logos, codes and markings.

A laser marking system can be adapted to many situations and it can be integrated in existing lines without effort.

The process of labeling trough CO2 laser marking is applicable to any sort of fruits and vegetables. Nevertheless, the best results are obtained with fruit and vegetables having a wooden or thin skin e.g. tomatoes, apples, grapefruits, walnuts, chestnuts, coconuts, pumpkins etc. In this sector it is possible to mark pieces of information such as produce traceability codes, expiration dates, logos of the producer and other personalized information.

The benefits obtained through natural branding are manifold:

• Small amount of energy consumption: the CO2 laser systems employs very small amounts of energy to do the job, resulting in a reduction of costs.
• No consumption of plastic, paper or glue: in CO2 laser labeling of food, labels are directly engraved on the surface of the product. Therefore the environmental footprint can be reduced to a minimum.
• Cleanliness: with CO2 laser marking, the products don’t come into contact with chemical substances like glue. Hence the wholesomeness of the produce is enhanced.
• Higher productivity: the laser marking process is very fast. Although the processing speed depends on the complexity of the information that must be engraved, in most situations the processing time ranges from fraction of seconds, for simple codes to a few seconds, for complex geometries.

At this stage it should be clear why laser labeling of fresh produces is also known as natural branding. It should also be clear how laser labeling is suitable for producers of organic or biological produces and, in general, for all the companies interested in improving their environmental footprint.

A case study: marking traceability codes on apples

Let’s see now how a CO2 laser labeling system has been applied to a line of selection and sorting of fresh produces, in this case apples.

This system was composed by a laser scanning head, a low power CO2 laser source with a wavelength of 10.6 micrometers and a computer with the software that controlled the entire process. The marking system was designed for the integration in the existing machine and was engineered to achieve laser marking of apples on the fly.

That means that the system was able to determine the position and the speed of each apple passing on the moving belt, thus synchronizing the behaviour of the laser beam with the position of the apples on the belt.

The system proved to be extremely fast: it could mark 6 apples per seconds. As we said this speed it’s not fixed but depends on the complexity of the results that need to be achieved.

The energy consumption of this system was of the lowest: the laser source in this applications consumed only 0,3 kW. Although it was designed for apples, this configurations of a laser labeling system can be extended to any typology of fresh fruit and vegetables and seamlessly integrated in existing production lines.

A safe process that doesn’t affect the quality of produces

Laser labeling is a safe process. The marking only affects the most superficial layer of the skin of fresh produces; all the organoleptic properties of the food are respected. They are not modified in taste, color or smell. And the shelf life remains the same: some papers have also highlighted that laser marking never reduce the quality of produces.

The laser labeling of fresh products is an application yet to be explored. The possibilities are wide and let companies greatly improve their environmental footprint.