Sahand Carpets

Finishing of carpets for value addition

Picture of Sahand Carpets
Sahand Carpets


1. Introduction

In today’s globalized world, the term “value-added product” is familiar to us. In the competitive carpet market, where price and quality are paramount, it is impossible for a product not to offer added value to customers. To overcome this challenge, innovation in the product is crucial. Innovation that creates buying motivation in today’s aware customers.

This is where research and development come in to offer a wide range of value-added carpets with practical, high-quality designs at the most competitive prices. Carpets that deliver more than just beauty, functionality, and comfort.

But the story doesn’t end here. Ultimately, customer satisfaction is what matters most in the competitive carpet market. In the realm of value-added carpets, merely selling carpets at a certain time is not enough. Providing after-sales services and maintaining the sold carpets are also of utmost importance. These parameters determine whether the customer remains loyal to your brand for their next purchase and whether they recommend your brand to others or not.

1.1. Need for Value Addition in Carpet Finishing

In today’s world, customers seek products that go beyond beauty to fulfill their needs and desires. This holds true for carpets as well. Therefore, we witness the production of a wide range of value-added carpets designed for various purposes with special and practical features.

Choosing the right fibers for carpets is the first step in creating a value-added product. Synthetic fibers such as nylon, polyester, and especially polypropylene, due to their high resistance to wear, reasonable price, and ease of maintenance, are ideal for high-traffic areas such as hotel lobbies and living rooms. These fibers can be processed with additives and different colors to give a beautiful and unique appearance to the carpet.

In addition to the type of fibers, the type of carpet treatment also plays a crucial role in determining its added value. Various treatments such as anti-static, anti-microbial, fire-resistant, and water-resistant exist, each with its own specific benefits. Choosing the appropriate finish depends on the type of carpet usage and your specific needs.

For example, carpets used in nurseries or hospitals should have anti-microbial properties to prevent bacterial growth. Whereas carpets used in high-traffic areas like hallways should be stain-resistant for easy cleaning.

1.2. Precautions to be taken during the finishing process of carpets

Attention to human health and environmental preservation is a top priority. This is also of utmost importance in the carpet industry and its finishing processes.

There are various methods for carpet finishing, which can be categorized into physical, chemical, biochemical, and physicochemical methods. The durability of these finishes can be temporary or permanent.

One way to classify practical carpet finishes is based on their performance:

  • Stabilizing finishes: such as anti-soiling finishes
  • Comfort finishes: such as waterproofing, anti-rot, and softeners
  • Appearance-preserving finishes: such as abrasion resistance, anti-pilling, and backing coatings
  • Safety finishes: such as flame retardant and water repellent
  • Biocide control finishes: such as antibacterial

In recent years, the use of some old chemical substances in carpet finishing has been prohibited due to their harmful effects on human health and the environment. For example, formaldehyde, which was previously used in some finishes, is now recognized as harmful, and formaldehyde-free alternatives must be used.

Furthermore, the finishing process should be such that it does not cause color change during its execution or throughout the useful life of the carpet. Additionally, to prevent deformation of the backings of thermoplastic carpets, finish stabilization should be performed at temperatures below 150 degrees Celsius.

The fibers used in carpets should have low moisture absorption properties so that moisture can quickly dissipate and finishes can dry properly.

Overall, the carpet finishing process should be economical and cost-effective while providing high-quality performance.

Adhering to all these considerations alongside the use of environmentally compatible and socially responsible methods will lead to the production of high-quality carpets following international standards.

2. Fire retardant finishes

During a fire, factors such as flammability, flame spread, heat release, and smoke and toxic gas emissions are of utmost importance. Smoke, toxins, and corrosive gases are also considered secondary hazards that must be taken into account.

Common flame retardants for cellulosic or lignocellulosic fibers, such as cotton, include materials containing nitrogen or phosphorus. These materials decompose at lower temperatures compared to untreated materials.

Today, formulations based on tetrakis hydroxymethyl phosphonium chloride (THPC) and melamine resin, pyrovatex, and melamine resin are widely used due to their high efficiency and excellent durability against washing.

To impart fire retardant properties to cotton-containing carpets, cross-linking systems with poly carboxylic acid are used. This process is carried out through spraying, drying, and baking. Phosphorus-based catalysts such as sodium hypophosphite or sodium phosphate can accelerate the reaction with cellulose. However, non-phosphorus catalysts such as sodium bicarbonate and carbonate are equally effective.

By using appropriate fire retardant finishes, carpets can be protected against fire hazards, thus safeguarding the lives and properties of individuals.

3. Soil-release finish

Soil-release finishing is carried out using specific chemical substances that penetrate the carpet fibers, making them hydrophilic. This allows water and detergents to easily penetrate the fibers and remove dirt and contaminants.

With soil-release finishing, carpets can be easily cleaned without the need for frequent washing. This finishing helps protect the carpet fibers against dirt and contamination, thus increasing the carpet’s lifespan. Soil-release carpets maintain their appearance for a longer period and become less dull and discolored over time.

There are two main types of soil-release finishes:

  • Oleophobic Finish: This type of finish uses fluorocarbons, which are oil-repellent and resistant to dirt.
  • Silicone-based Finish: This type of finish uses organosilicon compounds, imparting hydrophilic properties to the carpet fibers.

4. Water-, oil-, and stain-repellent finishes

In recent decades, the concept of easy maintenance in the carpet industry has become increasingly important. Customer demand for carpets that are easy to clean has led to the production of protectants that repel water, oil, and stains.

Nature has inspired us! Surfaces in nature such as the petals of a blue lotus, the feathers of a duck, the wings of a butterfly, the petals of a red rose, and the scales of a fish have exceptional water-repellent properties. This inspiration has led to the creation of protectants for carpets that repel water, oil, and stains.

Carpets easily get dirty because dirt and water and oil stains accumulate on them. The main goal of repellent protectants is to prevent any liquid droplets from spreading on the carpet and wetting its surface. The liquid droplet should remain on the surface and be easily cleaned. It is evident that such capability is achieved only when the interaction between the fiber surface and the liquid is significantly reduced.

5. Antistatic finishing

Carpets, whether made of natural fibers or synthetic ones, can generate static electricity due to friction with feet or objects. This issue is more noticeable in carpets made of synthetic fibers such as polyester, polyamide, and polypropylene, which are mostly used in homes and commercial spaces.

The main problem with static electricity in carpets is the occurrence of mild electric shocks when walking on them. Not only is this unpleasant, but it can also be dangerous for elderly people or children.

Furthermore, static electricity attracts dust and dirt to the carpet fibers, making it appear dirtier. In rare cases, sparks caused by static electricity can lead to fires.

For this reason, antistatic finishing for carpets is of paramount importance. This finishing is done using specific chemical substances that penetrate the carpet fibers and neutralize their electric charge.

6. Antimicrobial finishing

Due to their pile structure, carpets can become a breeding ground for microbes, bacteria, fungi, and mold. These microorganisms can not only degrade the carpet fibers, change their color, and create unpleasant odors but can also pose health risks to humans.

For this reason, the use of antimicrobial finishes for carpets is of paramount importance. This finishing is done using specific chemical substances that penetrate the carpet fibers and prevent the growth of microbes.

Antimicrobial finishes chemically protect the textile substrate, eliminating this microbial attack. Generally, antimicrobial agents first protect the user against pathogenic microorganisms and odor-causing microbes, and secondly, they prevent degradation of the substrate itself. Carpets are extensively used in various institutions such as hospitals, offices, schools, airports, and more. Their domestic use is also widespread. Carpets are primarily used for comfort, acoustics, aesthetic value, thermal properties, fall prevention, etc. However, while meeting these needs, carpets can act as prominent hosts for microbial growth. Common cleaning methods like carpet shampooing or vacuuming may not effectively clean carpets due to limited penetration into the pile. In a moist and warm environment, microorganisms can rapidly grow, and when they secrete specific enzymes, they can cause fiber degradation, color changes in products, cross-contamination, unpleasant odors, and even sometimes skin lesions upon contact with bare skin. Therefore, the real solution to this problem is to prevent the growth of bacteria, fungi, mold, etc., in both visible and non-visible parts of the carpet. Hence, the use of antimicrobial finishing agents is highly essential. Not all chemical substances harmful to microorganisms can necessarily be called antimicrobial agents. There are specific criteria that turn a chemical substance into a useful antimicrobial product. First and foremost, it must be effective against a wide spectrum of microorganisms. At the same time, it must be safe for the user. For example, it should be non-toxic, non-irritating, and non-allergenic for consumers. This substance should withstand multiple washes, dry cleaning, ironing, etc., without losing its efficacy and should not have any deleterious effects on the substrate itself. It should be compatible with dyeing and other finishing processes.

7. Insect-repellent finishes

Wool is one of the most commonly used natural fibers for carpet production worldwide. Wool and other animal fibers such as cashmere contain keratin in their chemical structure. There are specific insects such as clothes moths, carpet beetles, and carpet moths that feed on these keratin-containing fibers during their larval stage. Additionally, in many cases, dust mites begin to inhabit carpets, leading to allergies, asthma, and dermatitis. Therefore, keeping these insects away from carpets is essential. Some chemical finishes can protect keratin fibers from these insects, known as insect-repellent finishes.

8. Carpet finishing with the softeners

Carpet finishing with softeners involves the application of a supplementary substance that can impart softness to the fibers. This is one of the most significant tactile improvements that can be made to textile products. Although this can be achieved through various methods, the most common approaches in carpet production are mechanical or chemical methods. When it comes to the feel of fabric or carpet, this characteristic is entirely subjective. However, it is essential to mention that using softeners improves the tactile sensation on textile surfaces. Modern softeners, besides providing the expected direct properties such as increased softness and aesthetic value, should also be durable, antistatic with the ability to regulate potential moisture, and resistant to wear and tear.

9. Aroma finishes

Aroma finishing is a process where we enhance the value of textiles by adding aromatic substances to the product. Various research articles describe efforts to impart fragrance to fabrics and carpets. Additionally, aromatherapy has broad clinical applications and has been shown to be effective in treating depression and controlling anxiety in cancer patients.

In the past, scented oils were commonly used for this purpose, usually applied directly as a spray. Nowadays, microcapsules containing aromatic substances are applied as the main core on textile surfaces. The larger the size of the microcapsules, the easier the release of the fragrance. Microcapsules can be applied by methods such as exhaust dyeing, impregnation, spraying, coating, or direct incorporation into fibers without changing their color.

10. Future prospects

Throughout history, carpets have played a fundamental role in homes and public spaces, evolving over time to adapt to our increasing needs and desires. In the future, we will witness exciting innovations in the carpet industry that will be based on three main axes: comfort, health, and sustainability.

With ongoing innovations, carpets will play a role in the future that goes beyond just being a floor covering and will become an essential element for healthy, comfortable, and beautiful homes and spaces.

11. Conclusions

Carpets have become an integral part of modern consumers’ lifestyles because consumers don’t just look at the practical benefits of carpets. They see carpets as beautiful and decorative products and symbols to showcase their lifestyle. Today’s carpets, with their beautiful designs and combinations of special fibers, are not only used in homes, hotels, and offices but also in public places such as airports, airplanes, vehicles, and more.

In addition to choosing suitable fibers like polypropylene and beautiful designs, carpets will benefit from various types of complementary coatings with specific functions based on their usage. These special coatings impart multiple properties such as antibacterial, fire-resistant, dirt-repellent, or stain-resistant to them. Recently, carpets with pleasant fragrances and insect-repellent properties have also gained more popularity. These fragrant carpets may also offer therapeutic benefits. Therefore, investing in and completing carpets is truly a powerful tool for adding value.