IML(In Molding Label)

FAQ Guide

In today’s more competitive market, brands are compelled to get consumers’ attention. Product packaging also has the responsibility to shape consumer behavior because the way a product is packaged can potentially contribute greatly to its perceived value and appeal. In-Mold Labeling (IML) is a new process that’s revolutionizing the world of product packaging. In this blog article, we will take only a mere 5 minutes to venture into the wonderful world of IML, learn about its intricate process, material employed, and the long list of advantages that it brings to products.

1. What is IML?

IML, or In Mold Label, is a revolutionary injection molding process that integrates labels with molded products. This innovative process makes it possible to manufacture bright, long-lasting, and perfectly integrated labels that really grab the store shelf.

With IML technology, a pre-printed paper label or plastic film label is softly inserted into the mold. The label then gets fused perfectly with the thermoplastic material while molding, smoothly integrating the production and labeling process without post-labeling. Once cured, the label and container become one water-resistant and scratch-resistant product.

2. Types of In Mold Label

While In Mold Labeling (IML) offers significant benefits and cost-saving advantages, it is imperative to acquaint yourself with the distinct variations available to select the most fitting option for your project. There exist three primary types: injection, blow, and thermoforming IML. However, comprehending their unique methodologies and specific applications is crucial in determining the most suitable choice for your endeavor.

1) Injection Molding IML

This category is particularly well-suited for large-scale production as it entails infusing molten plastic material subsequent to the insertion of the label into the mold’s cavity. This process yields products with a premium finish sans the necessity for post-labeling. Its key strength lies in its exceptional precision, making it ideal for labeling intricate structures in substantial quantities.

2) Blow Molding IML

The special advantage of blow mold IML is that it is applicable for labeling plastic bottles and containers with air to mold. Put the labels in the blow molds first and then insert air to shape the product as one single entity with the label perfectly attached to it. Accuracy in positioning the labels in the blow molds should be attained with care so that the labels do not scratch and wear away during production.

3) Thermoforming IML

Since labels need to be placed inside the mold utilized in thermoforming before the plastic item is formed, a thermoforming mold is instrumental to this process of in-mold labeling. In producers of thin-plastic IML covers, lids, and trays, this is the type of IML that can be utilized. Its biggest strength is its flexibility, where labels can be created using a diverse range of materials.

Apart from their unique advantages, IML types can be used for various applications, such as complex forms and designs. In order to select the correct IML type, the material type, shape, and design must be taken into account. Making the right choice is easier if you consult with seasoned IML manufacturers.

3. Materials and Substrates of IML

The selection of the appropriate materials to use in the process of in-mold labeling is a vital thing to remember as not all materials can support this. Your correct selection of the material in the right in-mold labeling category for your job is more vital.

In mold labeling processes, materials with excellent molding characteristics are most sought after. Polypropylene is also a better choice for IML use because it is hardy, has good thermal characteristics, and is versatile. Polyester and polyethylene are also widely used materials with their own toughness, flexibility, and printability. All three can be molded into high-temperature and high-pressure applications because they exhibit remarkable resilience against hostile thermal conditions.

But label material compatibility with other plastic substrates is not a determinant factor in IML processes as some materials may not be compatible with plastics. For instance, using PP labels on mutually compatible plastics such as polyethylene and polypropylene, which belong to the polyolefin family of plastics, is highly suggested.

This kind of material might not even be suitable for crystalline plastics such as PET, nylon, and polycarbonate. Conducting compatibility testing to ascertain that labels properly stick on plastic materials is normal practice. This avoids hassles such as warping and other forms of deviation. If ordinary label material is not suitable, then substrate material of required specifications such as flexibility, reflective nature, and hardness may be utilized.

However, some surface treatments may be necessary to enable the efficient bonding of such substrates to the plastic material.

Ultimately, appropriate materials to use for labelling are based on the choice of plastic material to be utilized for the product.Moreover, a meticulous evaluation of compatibility concerns will ensure a superior finish characterized by exceptional durability in your in-mold labeling application.

4. How does IML Work?

The dynamics of the in-mold labeling (IML) process provide a new universe for product enhancement. Out of the numerous processes employed, three superior techniques—i.e., injection molding, blow molding, and thermoforming—rule the universe of IML. Even though every technique has its own unique advantages, the labeling process is what sets them apart.

1) In Mold Labeling Injection Molding

Injection molding is the backbone of the in-mold labeling process, hailed for its dominance and effectiveness. Under the deceptively simple exterior of injection molding exists a web of variables that require scrupulous control to achieve the flawless quality of the resulting plastic parts. An in-depth understanding of the process and the parameters gives manufacturers the confidence to procure plastic part suppliers who can provide the quality and consistency desired.

The in-mold labeling injection molding process proceeds as follows:

(1) Selection of an Appropriate Thermoplastic and Mold

Prior to commencing the process, proper selection or designing of suitable thermoplastics and molds is critical since these aspects constitute the very core of manufacturing and shaping the final parts. Thermoplastics-mold interaction calls for careful consideration in order to make intelligent choices, as certain forms of plastics may not function harmoniously with particular mold structures.

(2) Thermoplastic Feeding and Melting

Injection molding machines may be powered by electricity or hydraulics. The raw thermoplastic pellets are loaded into the machine’s hopper to start the process. When the screw is rotated, they are injected one at a time into the machine’s barrel. Through the combined action of screw rotation and barrel heat, the thermoplastic undergoes a gradual process of heating and melting until it attains a molten state.

(3) Plastic Injection into the Mold

When it arrives at the end of the barrel, the molten plastic closes the gate and the screw advances. It draws some amount of plastic through, creating pressure within in preparation for the injection. Simultaneously, an available label is positioned inside the mold. The two components of the mold tool are firmly secured together under substantial pressure or clamp pressure.

Fine-tuning of injection pressure and clamp pressure is essential to ensure proper component development and prevent plastic leakage during injection. Once the requisite pressure levels are achieved in the tool and screw, the gate opens, the screw advances and the molten plastic is injected into the mold.

(4) Holding and Cooling Phases

Injection of plastic into the mold is mostly followed by pressure sustained for some duration. This may depend on the type of thermoplastic and the part’s complexity. It varies from a few milliseconds to several minutes. This holding is necessary to give the plastic time to form and pack out the tool. When cooled, it conforms to the mold and bonds with the label.

(5) Finishing and Ejection Procedures

At the conclusion of the holding and cooling stages, plates or pins push the products out of the mold, leading them to the bottom of the machine where they are transferred onto a conveyor belt or into a container. The end product is a precisely produced plastic product with a perfectly integrated label.

The completion of the molding process completes plastic mold labeling, without the need for secondary processes and post-labeling. The in-mold labeling injection molding technique stands as a beacon of efficiency, finding widespread application in the production of computer keyboards, mobile phone keypads, and compact plastic paint buckets.

2) In Mold Labeling Through Blow Molding

Among the pantheon of techniques for in-mold labeling, blow molding emerges as a prominent contender. Within this process, the raw plastic material undergoes a metamorphosis into a parison—a hollow tube with one aperture. Analogous to in-mold injection, the decorative label finds its abode within the cavity wall of the mold, intertwining with the molded plastic as it cools within the mold cavity.

The realm of blow molding unfolds through three distinct processes:

(1) Injection Blow Molding

A blow or core rod is utilized throughout the injection blow molding process. A parison is first poured into the split mold cavity around the rod. The resulting parison has a test-tube-like appearance. Through the core rod, the parison is fed into the blow mold machine, where compressed air produces the final form. Afterward, the final product is transferred to the rod, which extrudes it.

(2) Extrusion Blow Molding

Within the tapestry of extrusion blow molding, two variations—continuous and intermittent—beckon. In continuous extrusion blow molding, each form sprouting from a perpetually supplied parison is deftly severed with a blade. Conversely, intermittent extrusion blow molding orchestrates the extrusion of fresh plastic from the metal mold after the antecedent plastic has been evicted, cooled, and nestled within the mold.

The allure of extrusion blow molds lies in their swifter creation and lower cost relative to injection blow molds, rendering them ideal for smaller production runs. While the benefits encompass diminished tooling expenses and expedited production cycles, the drawbacks often manifest as diminished control over wall thickness and heightened material wastage.

(3) Injection Stretch Blow Molding

A harmonious fusion of injection molding and blow molding characterizes the ballet of injection stretch blow molding. The plastic undergoes an initial transformation into a solid preform, culminating in the creation of a threaded bottleneck. Subsequently, a stretch blow mold machine cradles the preform post-cooling. Filled with pressurized air, the plastic bottle is altered, and the preform saturates in the glow of an infrared heater.

This process largely produces vacant plastic items, reminiscent of yesterday’s glass bottle production. Plastic bottles now represent the peak of this method’s perfection, serving containers for a whole array of liquids—everything from shampoo and dish soap to ketchup and sauces.

3) In Mold Labeling Through Thermoforming

Thermoforming, a difficult process, is the delicate heating of a sheet of thermoplastic to a state where it is pliable. Once spread over a mold with single elegance, the sheet undergoes a silent transformation as it forms itself to the form of the mold, hardening into its final shape as it cools in elegance. In thermoforming, three illustrious methods—vacuum forming, pressure forming, and mechanical forming—are pillars, shaping the sheet into its desired form.

This thermoforming creativity defies limits, and it has a world of applications in multiple industries.

(1) Shaping

Through the deft touch of a shaping implement, heated plastic sheets are sculpted into precise forms. Unlike the all-encompassing heat of injection and blow molding, the plastic sheets are delicately warmed around the shaping tool. Post-cooling and solidification, the once pliable sheets assume the contours of the formative mold, embodying a new identity.

(2) Heating

Before the heated plastic sheets envelop the forming tool in a dance of transformation, a printed label finds its place within the mold. The molten plastic sheets, as they cool and solidify within the mold, embrace the printed label, birthing a plastic creation bedecked in its entirety.

The tapestry of thermoformed creations predominantly comprises rigid plastic packaging, essential in the crafting of plastic vessels like cups. This method finds resonance in the creation of containers for delicacies such as ice cream and coffee.

Plastic tubs, guardians of frozen delights, also owe their existence to thermoforming artistry. Aside from the packaging, thermoforming performs its alchemy into creating a variety of products—from blisters and trays to lids—to cater to industries from culinary to medical to retail.

Thermoforming is just one example of how art and science collaborate to infuse life into a universe of creations that adorn our day-to-day existence with functionality and beauty.

5. Advantages of In Mold Label

The realm of In-Mold Labeling (IML) technology unfolds a tapestry of advantages that have elevated it to a position of indispensability across diverse industries. Here, we delve into the exquisite advantages of this technology:

1) Diverse Decorative Possibilities

IML technology provides a symphony of decorating options, marked by fast design transitions and the use of multi-color as well as lithography printing methods. This yields the production of products with better quality that is resistant to abrasion, thereby maintaining durability and beauty.

2) Aesthetic Enhancement

IML technology is more than mere decoration, bringing the appearance of products to new heights. With attractive designs and captivating images, products employing IML easily attract the attention of potential customers. Adding product data in the labels also contributes to the attractiveness, as well as contributing to structural rigidity with the smooth association of label and product. The permanence of this fusion ensures that the label remains unblemished throughout the product’s lifecycle.

3) Enhanced Production Efficiency

IML technology heralds a new era of production efficiency, characterized by reduced production times and lower costs. By enabling the simultaneous production and decoration of containers, the need for storing blank containers is obviated, thereby eliminating storage and transportation expenses.

4) Counterfeit Prevention

The sophistication of IML necessitates the use of personalized molds that are precision-engineered and come with high capital investment. Mold production sophistication and related expenses serve as convincing barriers to imitation practices. The personalized mold configurations, coupled with the sophistication of printing films and labeling, render imitation highly improbable. The support thus serves to defend brands against possible counterfeit products, defend the integrity and authenticity of the brand, and defend the brand’s reputation and value.

6. Disadvantages of In Mold Label

The application of advanced tooling and robotics in in-mold labeling entails a tremendous cost, and therefore, it adds to the overall cost of production of this technique.

Furthermore, the time demands of in-mold labeling pose a significant challenge. Extremely long runs are needed in production, as short runs are exorbitantly costly and entail lengthy setup times, and this creates operational inefficiencies.

The cost-effectiveness of in-mold labeling is also eroded by the frequent tooling adjustments required during the course of labeling, leading to interruptions and added costs.

Moreover, there is an appreciable issue of the large rate of defects in the produced goods due to this process. Defect rate is a vital measurement that depicts the percentage of defective components over overall production output. A rise in the defect rate reflects sub-standard manufacturing processes with a diversion from the preferred design and at the cost of product quality.

7. Applications of IML

The versatile nature of In-Mold Labeling (IML) technology has heralded a new era of innovation across a myriad of industries, with label manufacturers in India spearheading the adoption of this packaging marvel. Here, we illuminate the profound impact of In-Mold Labeling in key sectors:

1) Automotive Sector

Within the realm of automotive excellence, IML technology shines brightly, particularly in the realm of car interiors. Here, it enables the creation of robust control panel labels, interior trim components, and distinctive branding elements. The resilience of IML against the ravages of time elevates the durability and aesthetic allure of vehicles to unparalleled heights.

2) Consumer Electronics

In Molding labels are widely adopted in the consumer electronics sector for their durability. As a result, remote controls, mobile phones, and home appliances have a sleek, seamless appearance.

3) Medical Devices

IML stands as a beacon of precision and reliability. Vital for accurate labeling in the medical sphere, IML technology’s resistance to harsh sterilization processes and chemical exposure ensures the longevity and legibility of labels on essential medical equipment and devices.

4) Toy Manufacturing

The enchanted world of toy manufacturing finds sanctuary in the protective embrace of IML technology. Colorful and playful labels, made with IML, withstand playtime stress and rigorous safety regulation, maintaining the integrity of toy branding and children’s safety in play.

8. Conclusion

Finally, the advent of In-Mold Labeling (IML) has actually changed the universe of packaging forever, unchaining its adaptability and depth of advantage in numerous domains.The novel approach not only managed to illustrate its effectiveness across many sectors, but also equipped the firms incorporating it with the competitive edge needed in the industry.

As the demand for visually attractive labeling options continues to increase, In-Mold Labeling producers are in a prime position to adapt to the changing needs of various sectors to ensure an effortless blend of functionality and design in the package arena.