Colour

Research has shown that a product’s colour and appearance are key factors to a purchasing decision, and to a product’s overall life cycle. Unquestionably, colour has become, and will continue to be a critical element in the successful marketing of any product.

We specialise in supplying superior colour and additive masterbatches to a wide range of industries. With more than 120,000 colours already developed and the help of market-leading technologies, we offer unrivalled colour matching expertise.

We are experts at developing colour masterbatches that meet our customers’ exact requirements. Our highly skilled colour technicians have a thorough understanding of the pigment polymer interaction process and use state of the art technology to precisely select the exact pigments and additives needed for our customers’ applications.

Over the years, colour and plastics have forged a vitally important partnership. Technological advances have given today’s processors an endless range of colour choices and forms. Functional additives can be incorporated into plastics, improving the appearance, quality, performance and value of the end product.

Following are brief descriptions of the types of colourants and common colouring methods:

Masterbatches

Masterbatches are highly concentrated pelletised colourants and additives dispersed in a polymer carrier. The manufacture of masterbatch is the core business of DuroColour masterbatch, however, we also supply the following:

Compound

Compound is the pre-colouring of the resin, so the processor does not need to add additional products to the resin, saving on equipment needed to blend, disperse or distribute the colour. Quality is high, however this is not a viable option for small quantities.

Dry Colour

Dry Colour is a pre-matched mixture of colours and additives in a powder form. Dry Colour is therefore messy to work with, however DuroColour supplies this product type to selective customers.

Liquid Colour

Liquid Colour is a cost-effective method where low levels of colourants are required (<0.5%) using a pumping system to disperse the liquid colour. There are several advantages to using liquid colour, depending on the application and polymer including easy colour changeover, excellent dispersion properties and small footprint.

Additive Masterbatches

The technology leader in additive masterbatches, DuroColour delivers innovative performance solutions to processors, compounders, and end users. Specified in every major market and industry, DuroColour’s comprehensive range of additive masterbatches offer opportunities to improve the properties, performance and quality of finished plastic products, whilst optimising productivity and costs.

The range includes an exceptionally broad selection of standard functional additives for many different polymer bases. Specified in every major market and industry, DuroColour’s comprehensive range of additive masterbatches offer opportunities to improve the properties, performance and quality of finished plastic products, whilst optimising productivity and costs.

UV Stabilisers

Just as unprotected human skin suffers from sunburn due to excessive ultraviolet radiation, plastics are also damaged by exposure to light.

DuroColour UV stabilisers provide outstanding protection against the degrading effect of sunlight, heat and oxygen on the mechanical, optical and physical performance of plastic parts. The UV stabilisers product family includes three major classes of UV stabilizers:

Nickel quenchers, which take over the absorbed energy and dispose of it either as heat, or as fluorescent or phosphorescent radiation. Their action is independent of polymer thickness, and they are mainly used to stabilize pesticide-resistant agricultural films.

Hindered amine light stabilizers (HALS), which do not absorb UV radiation, but act as radical interceptors, effectively inhibiting polymer degradation. Significant stabilization levels can be achieved at relatively low concentrations, regardless of wall thickness. HALS and UV absorbers are frequently used in combination to achieve the highest possible levels of light protection. For example, the DuroColour UV Stabiliser developed for stabilisation of shrink film, is based on HALS, UV absorbers and antioxidants.

UV Absorbers, which absorb harmful UV radiation, dissipating it as “harmless” thermal energy. Widely used in food, drug and personal care packaging, these active ingredients perform best in products with relatively thick wall sections, such as transparent blister packaging and hollow cosmetic tubes. Films, fibres and other products with thin cross sections will be afforded only limited protection by UV absorbers.

Flame Retardants

Since almost all plastics are based on hydrocarbons, they are combustible.

DuroColour flame retardant masterbatches help to protect people and property by delaying the spread of fire and toxic by-products and, in some cases, preventing ignition entirely.

Unlike reactive flame retardants, which are incorporated into the polymer molecule during polymerization, flame retardant Masterbatches allow variable dosing levels and thus flexibility during processing. The effects many be either physical or chemical, occurring in either the gaseous or solid phase.

The most common flame retardants include the following:-

1. The effectiveness of inorganic hydroxides (such as magnesium hydroxide and aluminium) is based on the dilution of the plastic as a combustible material. Because of their very high dosage requirement (>50%), inorganic hydroxides are preferably used in compounding.
2. Halogenated flame retardants (e.g., brominated and antimony systems) actively intervene in the free-radical-based combustion reactions in the gaseous phase and form less reactive by-products. This delays or interrupts auto-catalytic combustion. Highly efficient, halogenated flame-retardant additives are especially suitable for manufacturing flame retardant concentrates.
3. Compounds containing phosphorous, which facilitate the formation of a protective layer of carbon via the phosphoric acid produced during a fire. There have specific effects that are less universal in application.
4. Intumescent systems, which cause the formation of a protective ceramic-like layer via a combination of active agents (organophosphorus compounds combined with a “foaming agent”). Intumescent systems also have limited applications.

Antistatic Additives

The chemical structure of plastics makes them particularly susceptible to build-up of electrical charges, which attracts dust and accumulated static electricity. Eliminating the electric charges to maintain good product appearance is a must for successful marketing of food and cosmetics packaging. It is also critical to protect sensitive electronic packaging and to reduce a major fire hazard in production environments.

DuroColour antistatic masterbatches are formulated for use with virtually all polymers in injection moulded, blow moulded and extruded applications. They are easier to disperse uniformly than antistatic agents in liquid or paste form. The active ingredients of DuroColour Antistatic masterbatches can also be combined with other additives and pigments in a single easy-to-use masterbatch.

Antistatic agents are additives whose efficiency is measured either by determining the surface resistivity or the static decay. Without antistatic agents, the surface resistivity of plastic is typically between 1014 to 1015 ohms. Antistatic additives will lower the surface resistivity to 1009 to 1012 ohms. In order to achieve a higher conductivity, conductive fillers such as carbon black or carbon fibre or powdered metal must be added to the plastic.

Antifog Additives

Food packaging and horticultural films used with water-containing products often fog over on their inner surface due to the condensation of tiny droplets of moisture. Droplets are technically undesirable in greenhouse films, where good light transmission is essential for crop growth.

DuroColour antifog additive masterbatches eliminated the problem by lowering the surface tension of the water droplets, causing them to merge and form a continuous transparent layer that maintains the clarity of the film. For example, specialised DuroColour antifog masterbatch was developed for LDPE and LLDPE food packaging film. It does not affect the transparency of the film and withstands sudden temperature variations.

Antiblock Additives

DuroColour antiblocking additives modify the surface characteristics by creating a slight surface roughness or smoother surface, thus reducing the coefficient of friction. This prevents self- adhesion of plastic film or sheet, making it easier to handle. Typical applications include polyolefin films and polyester sheets used in food packaging.  

Depending on the grade specified, DuroColour antiblock masterbatch provides very good dispersion, optical properties and efficient antiblocking effects even at low dosing ratios. As an example, certain DuroColour antiblock masterbatch contains active substances in an LDPE carrier. Its good dispersion and small particle size make it suitable for thin-gauge applications at the recommended 0.5 to 1%.

Slip Additives

DuroColour slip lubricants improve the flow characteristics of plastics during processing. They also reduce the frictional resistance of end product surfaces, enhancing both appearance and function. In addition, DuroColour slip masterbatches can act as plasticizers and impact enhancers, as well as antiblock, antitack and antistatic agents. DuroColour slip masterbatches can be used in conjunction with other plastics additives including release agents and heat stabilizers.

Nucleants

DuroColour Nucleant masterbatches are mainly used to clarify PP resin. They influence the degree of crystallinity of polymers and increase hardness, tensile strength, modulus of elasticity and yield point, while also reducing cycle times. DuroColour nucleant masterbatch greatly improves optical properties such as transparency or translucency.

Chemical foaming agents, materials that generate gas upon decomposition, also act as nucleating agents. The fine grain spherulite structure of ingredients incorporated in DuroColour chemical foaming agent makes it an ideal nucleating agent in direct gassed PS and polyolefin foams. The nucleating effect results in small cell sizes.

DuroColour nucleating agents are available for gassed foam extrusion in powder and masterbatch form, in various concentrations and carrier systems. The optimal dosage of nucleating agents depends on the desired foam quality and all the other variables in the process. For optimization, a starting dosage of 0.2 to 0.3% (based on active ingredient) has proven to be favourable.

Corrosion Inhibitors

DuroColour anti-corrosion concentrates are used to protect ferrous and most non-ferrous metals for the deteriorating effects of corrosion. Typical applications are films used for packaging ball bearings, automotive spare parts and other metal components.

When extruding PE film with anti-corrosion concentrates, the active inhibitors are vaporized and well dispersed. The film protects the packaged part by condensing on the surface of the metal. DuroColour corrosion inhibitors are nitrite free, have a neutral odour and produce no adverse effects on the working environment.

Antioxidants

Oxidation and heat aging are major causes of degradation of plastics. Exposure to heart and oxygen causes a chain reaction involving the formation of free radicals, which inevitably leads to cleavage of the main chains in the polymer and degradation of the plastic. This is manifested in many difference ways including loss of shine and transparency, yellowing, surface cracking and odours. Oxidation can also result in loss of mechanical properties such as impact resistance, elongation and tensile strength.

DuroColour antioxidant masterbatches are formulated to combat thermo-oxidative decomposition at every stage of the plastic life cycle, from manufacturing, drying and processing through end use. They are particularly suitable for use in LDPE, HDPE and PP. An example of a specialised DuroColour masterbatch is one based on a combination of antioxidants for long-term heat protection of polypropylene caused by severe outdoor and/or heat exposure.

Anti-microbial Additives

Microorganisms such as fungi and bacteria are present in all environments, although they are invisible to the naked eye. The reproduction and growth of bacteria, fungi, mildew and moulds happen rapidly on plastic surfaces. DuroColour anti-microbial masterbatches inhibit the growth of these microorganisms, helping to prevent unpleasant odours, discoloration, and surface degradation of plastic parts.

Typical applications for anti-microbials include fibres and textiles used in athletic gear and household furnishings, kitchenware and bathroom products, automotive steering wheels and interior parts, pharmaceutical and medical products, and a spectrum of other plastic applications requiring a high standard of hygiene.

There are two major types of anti-microbials, both of which are represented in the DuroColour anti-microbial product line.

Organic anti-microbials consist of substances that migrate within the polymer matrix, spreading over the surface of the materials where their anti-microbial action has effect. Organic anti-microbials are effective at low concentrations, offering a favourable cost/performance ratio in polymers that are processed at temperatures not exceeding 250°C.

Inorganic anti-microbials incorporate substances containing silver in ionic form, bound to inorganic compounds that regulate the diffusion of ions within the polymer mass. The silver ion is the active ingredient that interacts with bacteria. non-toxic, non-corrosive and flameproof, inorganic anti-microbials have no negative impact on plastics processing. They are highly recommended for objects requiring long-lasting anti-microbial action and for engineering polymers that are processed at high temperatures.

Shutdown Purge

Plastics processing periodically requires complete removal of thermo-oxidized deposits from extruders and injection moulding machines. DuroColour shutdown purge masterbatches permit fast, economical cleaning of machinery to facilitate colour or resin changes with minimal downtime and loss of virgin material.

A shutdown purge Masterbatch should be a balanced mixture of surface-active substances and fillers with a low abrasive power, based on low-density polyethylene. Widely used for purging extruders and injection presses, the masterbatch allows quick changes and materials of varying viscosities.

Process Aids

DuroColour comprehensive line of DuroColour process aid additive masterbatches offer unprecedented opportunities to improve the properties, performance and quality of finished products, while also optimizing productivity and costs.

During the extrusion process, DuroColour process aid masterbatches coat the inner surface of the die, reducing the friction between the melt and the metal, allowing polymers to extrude more easily. By lowering the friction and eliminating or reducing melt-fracture and die build-up, DuroColour process aid Masterbatch enables difficult-to-process materials such as narrow-molecular-weight LLDPE and LLDPE rich blends to run on existing extrusion lines.

An example is DuroColour process aid masterbatch based on fluoro elastomers. Developed for LLDPE and metallocene film extrusion, it can be used in conjunction with high quantities of fillers, anti-blocking agents and inorganic pigments. In addition to eliminating melt-fracture and reducing die build-up, the use of this masterbatch enhances the optical properties of the film by improving its transparency.