| Zuletzt Online: 17.02.2022
Optimal Selection of Leveling Agent for Paints and Coatings
Finding the right leveling agent is often a tedious process, considering all the parameters. It is important to check dosage and product variations to figure out the correct chemistry and fine tune the formulation. Make the selection of your leveling agents easy for your coating formulation by getting answers to most of your questions that arise during the selection process. Learn the role of solvents and other important factors in leveling and, thus, come up with the best coating product.
Dyeing auxiliaries are defined as chemicals or formulated chemicals which enables a processing operation in dyeing to be carried out more effectively. Dyeing auxiliary includes dye fixing agents, cationizing agent, dispersing & leveling agents etc. They help in stabilizing the dyeing bath to improve the exhaustion, achieve level dyeing and improve fastness properties.
Need for Leveling Agents
It is admitted for many paints that a perfect appearance means also a perfect leveling. Poor leveling (like orange peel or ghosting) may not influence significantly the paint parameters in time, as it is more aesthetic orientated. But the leveling agent itself may cause some severe issues.
A correct leveling agent helps in reaching the wanted leveling and final film finish. But a wrong choice may lead to surface defects such as craters, pinholes, loss of gloss or even inter-coat adhesion problems. Therefore, to understand the leveling, it is important to understand the influence of the surface tension on the paint and finding a balance is critical:
Too low surface tension may be good for the substrate wetting but may lead also to a wavy surface.
Too high surface tension can cause adhesion and surface wetting issues.
If you are exploring the factors that govern leveling in any formulation, it might be worth to begin with an in-depth understanding of leveling basics (surface tension, contact angle, test method, etc.) at first.
Which leveling agent is suitable for your formulation?
There are several base chemistries to choose from when selecting a leveling agent & lower the surface tension to the point just that you need for a desired application.
The most common types of leveling agents are listed below.
Silicone-based agents (Polydimethylsiloxane modified - PDMS)
Acrylate-based agents (Polyacrylate)
Fluorocarbon-based agents (Modified Fluorocarbons)
Hydrocarbon-based leveling agents: less efficient than previous families
Understand each chemistry in detail and see which one fits best for your formulation & end-application needs.
Silicone oils are important tools in vitreoretinal surgery and their introduction has represented a pivotal moment in the management of ophthalmic surgery as they are equipped with a combination of chemical and physical properties that have propelled their surgical use. Silicone oils are essentially used as intraocular tamponade thanks to their ability to maintain the adhesion between retina and retinal pigment epithelium (RPE).
The safe and effective use of tamponade substances means the knowledge of their physical and chemical properties because it is on the basis of this knowledge that surgeons have to decide what type of tamponade they should use.
What is the function of softener flake softener for textiles
Softener flake is an important finishing process in printing and dyeing. It is also a chemical substance that can change the static and dynamic friction coefficient of the fiber. So what is the effect of softer flake on textiles? Here is a brief introduction.
When the static friction coefficient of the fiber changes, the hand will feel the smoothness of the fiber, reduce the friction between the skin and the fiber, and it is easy to move on the fiber or fabric; when the dynamic friction coefficient of the fiber changes, the microstructure between the fibers It will move and deform, and you can feel that the dynamic and static friction coefficient changes smoothly.
In the textile processing process, after many treatments, the fabric and the machine will directly rub against, easily damage and wipe the fabric and fiber, making the fabric and fiber feel rough, the general synthetic fiber feels worse, especially the microfiber fabric.
In order to make the fabric soft, smooth and comfortable, the fabric needs to be finished. The widely used fabric is treated with softer flake, which can make the fiber itself soft and smooth, meet the processing conditions, and avoid damage during processing. Therefore, it is also an important auxiliary for textiles.
The above is an introduction to the effect of softer flake on textiles. Thank you for your patience to read. If you need it, you can contact us directly.
Acrylic resins feature excellent transparency and durability, and are used in a broad range of applications from consumer items like lenses to industrial products like molding materials, coatings and adhesives.
About Acrylic Resins
Acrylic resins feature excellent transparency and durability, and are used in a broad range of applications from consumer items like lenses to industrial products like molding materials, coatings and adhesives. In addition, acrylic resins are also used in other areas, such as binders for paper/fiber processing, PC screens, display windows for cellular phones and light guide panels for liquid crystal display (LCD) backlights.
Due to their excellent durability and weatherability as coating materials, acrylic resins are used extensively in applications such as automotive, architectural and plastic coatings.
Acrylic resins have the below general characteristics.
? Appearance (gloss, build)
? Weather resistance
? Heat resistance
? Chemical resistance
? Water resistance
WHAT IS A DEGREASER?
A degreaser is a cleaner designed to remove grease, oils, cutting fluids, corrosion inhibitors, handling soils, fingerprints, and other contamination common in assembly, stamping and other metal fabrication in refineries, motor repair shops, airplane hangars, and factories, etc.. Degreasers go by a number of different names including precision cleaner, maintenance cleaner, as well as several specific for automotive repair such as carb cleaner or brake cleaner.
The objective for a degreaser is to remove the offending soil quickly, avoiding as much wiping and scrubbing as possible. Degreasing solvents are commonly packaged as an aerosol for convenience. Aerosols have the added advantage of providing a forceful spray that creates agitation and which penetrate small crevices.
Water-based degreasers are common in a trigger sprayer, or in gallon or drum containers for immersion or batch system cleaning.
Specialized equipment like ultrasonic or vapor degreasers are available for more automated cleaning. These processes are repeatable, so better suited for more critical cleaning applications, like aerospace or medical appliance maintenance.
Techspray offers a large selection of degreasers and maintenance cleaners under the G3?, E-LINE?, PWR-4?, and Precision-V brands, which range from economical heavy-industry cleaners to high precision solvents for sensitive components.
WHY DO I NEED A DEGREASER?
Dust, dirt, grease, and oxidation contamination can cause corrosion, slipping hazards, overheating, increase electrical resistance in contact areas, and many other issues. Degreasing may be required to prep for down-stream processes like painting or plating.
Cleaner Degreasers can clean oil, grease, oxides and handling contamination from equipment and assemblies that include:
Metal and fiber optic cable splices
Motors and transformers
Programmable Logic Controllers (PLCs)
Pneumatic and hydraulic assemblies
Electronics and electrical equipment
Industrial-strength degreasers are needed to remove grease, tar, asphalt, oil, and grime in these kinds of applications:
Clutches, armatures, generators, and compressors
Electrical motors and equipment
Bearings, chains, cables, pulleys and gear drives
Brakes, springs, and flywheels
WHAT IS THE DIFFERENCE BETWEEN A DEGREASER AND A CONTACT CLEANER?
Degreasers are intended to remove oil, grease, oxides and handling contamination from equipment and assemblies, while a contact cleaner does the same thing specifically for electrical contacts.
A contact cleaner (also called electrical cleaner, switch cleaner, electrical contact cleaner, and (specific for automotive repair) battery terminal cleaner removes contamination from electrical contacts, the conductive surfaces of connectors, switches and other electrical and electronic components with moving surface contacts.
WHAT DO I LOOK FOR WHEN SELECTING A DEGREASER?
There are several factors that can have a big impact on performance and safety in choosing the proper degreaser for a given application in an environment:
Flammability – Degreasers often contain very flammable alcohols and hydrocarbon solvents. They can be cheap and effective, but can be dangerous without proper ventilation, or around open flames, sparks (e.g. from welding), or hot surfaces. Nonflammable degreasers avoid these safety issues but are generally more expensive. In addition, some nonflammable cleaners can be very toxic, containing hazardous solvents like Perchloroethylene, trichloroethylene or n-propyl bromide. High flashpoint (often called “high flash”) solvents have vapors that are less likely to combust in normal ambient temperatures (say below 140°F/60°C).
Dielectric strength – If you plan to work on powered equipment, or need to switch it on before the solvent has flashed off, consider a degreaser with a high dielectric strength. Make sure you know the amperage and voltage of the circuits you are trying to clean before spraying anything onto the circuits, and evaluate the suitability of any cleaner in your application. Dielectric strength is the maximum electric field that the material can withstand before its insulating properties break down. The lower the dielectric strength, the more likely it will breakdown and allow electricity to flow through and short out.
Plastic / rubber compatibility – Care needs to be taken when cleaning plastic or components, rubber gaskets and seals. If the degreaser is incompatible with the plastic, it can craze (create small cracks), embrittle, or soften the material. Rubber seals may swell, shrink, or dissolve. A new degreaser should always be tested before being used broadly.
Toxicity – N-Propyl Bromide (nPB), Trichloroethylene (TCE) and Perchloroethylene (Perc) are highly toxic chemicals commonly used in degreasers to provide cleaning performance in a nonflammable formula. There are documented court cases where workers suffered major health effects when exposed to high levels of these chemicals. Workers reported headaches, dizziness, and even loss of full body control. There are also possible links to reproductive problems and cancer. All of this has caused maintenance facilities to reconsider their solvent choices, especially with manual cleaning when exposure tends to be higher.
Environmental issues – Volatile organic compounds (VOCs), solvents that add to smog, or solvents with high global warming potential (GWP) have been a focus of regulators. Some state (e.g. CARB, the California Air Review Board), municipal, and even industry-specific regulations restrict the use of high VOC or high GWP materials.
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