Resins Used in Industry

As Lefa Temsilcilik, since 2015 we have been distributing resins to the motor, electrical-lighting and transformer sectors under a distributorship agreement with Italian company Demak Group S.E. Special Engines. S.E Special Engines is expert in its field with a customer-focused approach and holds ISO 9001/2008 certification. Our fundamental objective is to support our customers at every stage, from preliminary project evaluations to product requirement assessments, working together with our technical team. Resins are widely used for filling and coating in electronic and electrical industries and are generally grouped into two categories depending on their chemical types: Epoxy and polyurethane.

1. Epoxy Resin Properties

Epoxy resins are part of the thermosetting group and possess high adhesive strength, chemical resistance and mechanical properties. Thermoset polymers are plastics that can achieve the desired shape in a single heat treatment process. The most important characteristic of epoxies, which are generally two-component, is their ability to easily transition from liquid to solid-hard state. Epoxies have very high resistance to high temperatures, water, acids and alkalis. With these properties, they protect electrical components in electronic industries against dust, moisture and short circuits. Standard epoxy resins have better thermal conductivity than air and distribute heat more efficiently.

1.2. Epoxy Resin Applications

They are used in various fields such as industrial coatings, aerospace and aviation industries, adhesives, composite materials and automotive industry.

1.3. Advantages of Epoxy Coatings

• Hygienic and antibacterial. • High chemical and mechanical strength. • Does not collect dust. • Resistant to wear. • Aesthetic. • Waterproof. • Easy to maintain and repair. • Long-lasting.

2. Polyurethane Resin Properties

Polyurethanes are a group of polymer compounds containing "urethane" bonds and can be formulated to possess a wide variety of properties. Polyurethane resins have very high chemical, dust and moisture resistance. They provide excellent electrical insulation and good adhesion for most metal and plastic materials. While epoxy resins provide rigid encapsulation when hardened, polyurethane resins remain rubber-like when cured. Thanks to these properties, they are frequently used in protecting sensitive circuit components. Polyurethanes have lower exothermicity during curing compared to epoxy resins. For this reason, it is recommended that cured polyurethane resins not be used above 130°C.

2.1. Polyurethane Resin Applications

Polyurethane products are successfully used in electrical and electronic encapsulation, cable joining, sonar devices, molding and prototyping applications.

4. Resin Application Areas and Types 4.1. Foam Gaskets

Demak, always considering customer needs, developed the FomexOne line for the FIPFG (in-place gasket foaming) process. This technology offers various applications and adhesive types according to every requirement. It can be applied as a gasket to a channel or flat surface, or as an adhesive to bond two surfaces on a flat or inclined surface. To cover many possible applications, Demak offers three different systems: • FOMEXONE as Liquid PU Systems for Pouring into a Groove: Flowable polyurethane self-levels and therefore spreads evenly throughout the channel pattern. • FOMEXONE as Thixotropic PU Systems for Pouring onto Flat or Inclined Surfaces: Thixo polyurethane foams regularly throughout the entire perimeter of the part to be sealed. • FOMEXONE as Adhesive PU Systems: The bonding is poured as a sealing cord between two layers on binding, gluing or layer overlap. Adhesion is applied without limitation to glass to glass, painted surface metals to glass, stainless steel to glass, painted surface metals to acrylic, stainless steel to acrylic and other bonding solutions.

4.1.1. Resins for Gasket Application

Demak's FOMEXONE GST line, a brand of special polyurethane products for foam gaskets, features self-leveling properties, good pressure distribution and solutions in a wide range of Shore 00 hardness. The most frequently used resin types in this area are GST TOO1 and GST F001. We have resins available for our customers' different requests and application areas. Automotive: Automobiles and all motorized vehicles are continuously exposed to moisture, water, dust and dirt, so they must be made hermetically sealed. FomexOne gaskets protect and preserve them perfectly. • FomexOne Gasket: Rear lights, interior lights, hazard lights, door trim strips, quarter windows, sunroof, pollen filters, air filters, pedal support, steel wheel support, fuel filler cap, speaker, electronic car boxes, ventilation grille. Moto-market: Panel gasket, rear lights, front glass. Naval market: Porthole sealing, panels. • FomexOne adhesives can be used for rear-view mirror and wiper blade polymers. Filters: FomexOne gaskets are ideal solutions for hepa filters and household filters requiring high degree of dust isolation, air filters, oil filters, fine dust filters, pollen filters, hepa filters, vacuum cleaner filters. FomexOne Adhesive: Oil filters, hepa filters. Household Appliances: Used in long-lasting household appliances. They affect the sealing and aesthetic appearance of components. FomexOne Gasket: Sink sealing, washing machine sealing, air-steam conveyor sealing. FomexOne Adhesive: Oven glass door sealing, cooktop sealing. Lighting: Used as protection from external agents. FomexOne gaskets are commonly used where protection of the lighting fixture is required. FomexOne Gasket: Decorative projector, architectural projector, light for fixed and portable applications, emergency lights. Waterproof light boxes, spheres for decorative lights, street lights, garden lighting devices, fluorescent lights, signal lights. Low-energy lights, central power supply and autonomous emergency devices, industrial lights. FomexOne is used for glass bonding in street lights. Panel: FomexOne gaskets make the protective function of the enclosure more effective thanks to their sealing properties. They are used in places such as packaging areas where they guarantee the quality of foam covers, particularly for electronic panels and electrical cabinets. FomexOne Gasket: Recessed distribution panels, surface and modular distribution panels, floor-mounted distribution panels. Water surface distribution and automation panels, recessed distribution panel and enclosure, plastic surface waterproof connection boxes, metal surface mounting, waterproof connection boxes. Push buttons, selectors and indicators, plastic barrel cap, tin drum cap. FomexOne Adhesive: Glass and acrylic sealing on distribution panel covers. 4.2. LED Coating: Demak offers many innovative polymer solutions for coating LED strips and LEDs on aluminum body profiles, with outdoor-resistant and excellent light-transmitting special resins. Demak-Led has successfully passed all tests proving it suitable for both indoor and outdoor applications. LEDs encapsulated with resin never encounter yellowing and aging problems. Types are available in hard, semi-hard and soft grades.

4.2.1. Resins for LED Coating

We have different products for solutions in various hardness levels from Shore D20 to Shore D85. Sepur 540 RT+DK 100 HV, Sepur 540 RT+DK 124 HV, Sepur 540 RT+DK 180 HV are our most frequently used resin types in LED coating.

4.3. Electrical and Electronic Filling

Resin applications are increasing due to the continuous miniaturization of components and more electronic products entering daily life. Filling is the process of filling a complete mechanical or electronic assembly with two-component thermosetting epoxies, polyurethanes or modified resins. Coating involves creating a mold or frame around an object; filling the space between the frame and the object with a thermosetting polyurethane or epoxy. The mold is usually removed after resin polymerization.

These processes are commonly used for the following purposes:

• Improving thermal distribution allowing components to be positioned closer together and bringing the product to smaller dimensions. • Protection against mechanical damage, vibration and impact. • Structural reinforcement, increasing mechanical stability and electrical insulation. In short, resins increase the life and functionality of components.

4.3.1. Resins for Electrical Insulation

As Lefa Temsilcilik, our fundamental objective is to provide you with extensive solution options in every area with polyurethane and epoxy resins. Epoxy resins have properties including a wide range of glass transition temperature, viscosity, high wetting and penetration between cables and wires, and resistance to moisture and water. Sepur 114 FR, Sepur 116 FR, Sepur 125 FR, Sepox 213 FR are among our most frequently used resin types for electrical insulation. 4.3.2. Application Areas With high-temperature class epoxy resin, it is possible to guarantee the flammability rating and durability of these high-voltage components. Resin casting provides protection against chemicals, moisture, dust and impact. Resin provides additional benefit for applications such as rail, automotive and marine transportation with its flame-retardant properties. Perfect insulation is provided in electric motors. It is aimed at motors operating at lower temperatures and therefore having higher durability. Additionally, resin greatly reduces vibrations and noise generated by the motor, providing structural reinforcement that ensures greater mechanical stability. In capacitor applications, the objective is to achieve perfect electrical insulation and provide longer service life under high temperature and high humidity conditions (T=85°, RH = 85%). In transformer insulation, epoxy or polyurethane is used as flame-retardant resin. Epoxy resin, due to its inherent properties, fills windings better and provides better thermal conductivity. To guarantee perfect sensor insulation in sensors, the distribution equipment must be very precise, as the amount of resin to be distributed is usually very low. Thanks to Demak resins, you can guarantee a perfect end result without air bubbles.

4.4. Sealing and Adhesion

Demak offers complete solutions for adhesives and filling compounds suitable for use on many different substrate types. Main application areas are automotive, household appliances, marine, electronics, composites, renewable energy, medical and healthcare, telecommunications.

4.4.1. Resins for Sealing and Adhesion

Our products that we represent are excellent for bonding metal, plastic and elastomers in automotive, mechanical, photovoltaic, electronic and electrical engineering fields. The most frequently used resin type in this area is Sepurbond 120.

Shore Hardness Scale Table Note: Shore is the term used to determine the hardness value of plastic or flexible materials.

  5. Technical Data Information of Our Products 6.1. Our Resin Products Used for Lighting   6.2. Our Resin Products Used for Insulation 6.2. Our Resin Products Used for Insulation Note: Our table covers the resin types we commonly use. We also have different types of resins for special applications. Mehmet Ali Başaran Business Development Specialist Lefa Temsilcilik