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Appropriate color measurement tests can help you create fiber cement siding that is as beautiful as it is durable. Image Source: Shutterstock user Kiattisak Thongtawee

Fiber cement siding—a sturdy combination of wood pulp, fly ash, portland cement, and water—was first introduced in the construction industry just 25 years ago.1 Since then, it’s become one of the most popular materials that architects use for their projects. Almost 15 percent of all new homes have fiber cement siding, in part because this material is so durable and versatile. Although this material can be made to look just like brick, stone, or wood siding, it is actually far stronger than wood or vinyl materials, and less expensive to make than brick or stone. Quality fiber cement siding is fire resistant, termite-proof, rot-proof, and can withstand extreme weather conditions like heavy rain, strong winds or fluctuations in temperature.

But in order to achieve both the durability and beauty of fiber cement siding, manufacturers have to use appropriate color measurement methods at different points in the manufacturing process. Siding color is often the first thing that visitors notice when they look at a house, which is why it’s so important to test for color accuracy before you sell your products to customers. Even subtle inconsistencies in color could make fiber cement siding appear cheaply-made or weather-worn, and will negatively impact the overall appearance of the house. By using spectrophotometric color measurement during manufacturing, you can ensure that every piece of fiber cement siding meets your exacting standards and that your final product will appear beautifully-crafted.

Unpainted fiber cement siding is usually light grey in color. Image Source: Wikimedia user Michael Holley

Double beam spectrophotometers illuminate both a reference source and a sample simultaneously to produce more reliable, repeatable measurements. Image Source: Unsplash user Greg Becker

Spectrophotometers have revolutionized the way product color is measured across numerous industries, from maxillofacial plastics to maple syrup. By allowing for full-spectrum analysis of both reflected and transmitted light, spectrophotometers offer the most advanced method of objectively quantifying chromatic information possible today and give customers virtually endless options for obtaining accurate color measurements. However, not all spectrophotometers are created equal; recent technological advances have expanded the versatility of optical configurations and understanding your options is critical when choosing the right instrument for your purposes.

Single Beam Systems

The first spectrophotometers were based on a single beam configuration that is still in use today. The light source in this type of configuration is concentrated in a single beam, requiring discrete measurements of each object. In practice, this means calibrating the machine prior to each test by measuring a reference standard and making any necessary corrections to compensate for light source changes during the standardization process. Single beam instruments have historically suffered from deteriorating accuracy over time and unpredictable repeatability, primarily due to the instability of light sources. With advances in tungsten halogen lamp stability, single beam configurations have enjoyed increased reliability in recent years. However, standardization every 4-8 hours is still recommended to ensure accuracy, impeding efficacy and making measurements vulnerable to human error.

Historically, the instability of light sources led to increased demand for double-beam instrumentation. However, today’s advanced illuminants have dramatically improved stability to offer enhance reliability in single-beam instruments. Image Source: Flickr user Paul Hudson

Everything You Need to Know About Dye Allergies

If you’re like most people in the world, you consume or come into contact with dye on a daily basis. Food, drugs, personal care products and textiles all make use of dye to change product appearance and help with identification. In the manufacturing world, dye is a critical component of a product — but it can have significant ramifications for specific customers.

People with dye allergies must be extra careful with the products they use and the food they consume. Let’s take a closer look at allergies to food dyes and what they mean for a product.

What Is Dye?

Dyes come from a wide variety of natural and synthetic sources. Each dye has its own properties and associated regulations. People have been dyeing products for centuries and have developed a range of styles and types of dyes. Food, drugs and textiles may all use different dyes to get their final colors.

One distinguishing characteristic of a dye is that it chemically bonds to the material, as opposed to pigments that do not bind to the substance. Its qualities become part of the item and can have effects on people who consume or come into contact with it.

What Are Dyes Used For?

Dyes are essential for a wide array of purposes, including:

• They make products look better. If your ketchup were a sickly brown color, it probably wouldn’t look very appealing. Dye can improve the visual appearance of various products, attracting customers and making their experience more enjoyable. In products like cosmetics, the dye is essential to give them the right color.
• They can help identify variations. Different flavors or options can benefit from various colors to help distinguish them from each other. In the world of pharmaceuticals, the right color can be critical in the proper identification of a drug.
• They improve consistency. Whether you buy a product in New York or Los Angeles, you expect similar levels of quality from the same manufacturer. During production, natural products can appear quite different. When you ensure the same colors and appearances are present consistently, customers retain confidence in your product each time they buy.

One of the most significant uses of dyes is in the food and beverage industry. You can also find dyes in cosmetic products, personal care items and drugs. Some products that frequently use dye include the following:

• Soft drinks
• Cereals
• Baked goods
• Candies
• Ice cream
• Canned fruits
• Chips
• Cheeses
• Fabric
• Pills
• Liquid medicine
• Cosmetics
• Mouthwash

Many variables affect color and visual appearance. Light, angle, and/or background all affect visual analysis and cause major variations in color perception. Image Source: Daniel Christensen via wikimedia.org

The human eye is a remarkable tool in identifying color variations. In fact, the human eye can actually distinguish over 7,000,000 different color variations in our known spectrum of colors. Science and technology have explored the eye-to-brain connection of how light is absorbed and reflected, and these results have shown that the human eye is capable of distinguishing even the slightest deviations in color.

Despite how amazingly accurate and complex human vision can be, the eye and the brain do have their limitations. Optical inputs of color variations are altered by a variety of causes that lead to problems with visual analysis, especially in plastic manufacturing. Manufactures have to be incredibly precise when creating their products, to account for the variations in the way we see things, and to mitigate against their negative effects. Spectrophotometry tools are incredibly useful in this process.

Limitations of the human eye

In the same way that no two people are alike, color perception also varies greatly from person to person. Color variations have also been noticed in many individuals between left-eye and right-eye differentiation. Even as you look at this screen, if you shut one eye and then alternate viewpoints with the other, you may notice the slight variations in color from your own unique perspective.

Though we all view colors in relatively the same way, our unique genetic make-up also plays an important role in how we differentiate between color variations. Just like any other physical ability or trait, vision varies in aptitude as well. It can range from highly effective to somewhat defective in its ability to classify color. From good to poor color vision or even color blindness, everyone has limitations when it comes to color analysis.

Take for instance the ability to see in the dark. The human eye is not able to distinguish color at all without some source of light. Even with minimal lighting, our brain will interpret color using only a limited scale of grey. It is certain that the human eye is a powerful tool, but despite its amazing competencies, we can see that there are a number of other factors that limit our abilities in perceiving color variations. Only with advanced spectrophotometric technology and controlled conditions can the brain accurately and consistently decipher variations in color.

Paper was invented in China, where people began writing on sheets of cloth to keep records. From there, a Chinese court official created a pulp using natural materials and let it dry in a thin mat shape. Paper production has changed over the years to become what we know today. At HunterLab, we are dedicated to helping the paper industry meet color standards and best practices for paper production.

Meeting Color Standards for Paper

White paper may seem like a simple color standard to meet, but getting the right white shade can be challenging when we consider surface properties. While there may be a specific white that all paper manufacturers want to achieve, they must factor how light reflects on different surfaces, from low-gloss matte to high-gloss.

Colors have reflected light and absorbed light, and these measurements affect our perception of the color. Reflected light, however, is not an indicator of the actual color, while absorbed light is. For mid-gloss and high-gloss paper, their shiny surfaces offer a lot of reflected light, and it will skew our perception of the color.

To find the right color, paper manufacturers rely on instruments that offer a quantified measurement for color, rather than counting on the human eye. Machines like spectrophotometers can register the light a surface reflects and absorbs to provide a definitive color measurement. With this method, manufacturers can achieve a consistent white paper in all glosses.

Plastic is a widespread medium for various applications, from children’s toys to kitchen tools. Coloring plastics can take on many different forms, and it’s vital to meet industry standards for safety and performance. At HunterLab, our spectrophotometers help plastic manufacturers create ideal color concentrates for their products.

ASTM Color Standards for Plastic

The American Society for Testing and Materials (ASTM) provides a series of standards for plastic production. While plastic is easy to mold and ideal for many applications, it’s a synthetic material that may be poorly made or unsafe for use.

ASTM standards provide rules and guidance for plastic production to ensure products last and stay safe throughout their lifespan. The organization’s website offers extensive documentation for you to follow these standards in your operation. Criteria include descriptions like:

• Specifications for materials
• Testing methods
• Production procedures

Color is an essential feature of plastic standards because plastic colorants can affect the quality of the material. Plastic producers use color charts to compare their colors, and the best way to handle this comparison is with color measuring devices. Machines like spectrophotometers quantify color based on the light it absorbs and reflects, so manufacturers can create a match to a color on the chart.

What Are Color Concentrates for Plastics?

Color concentrates are plastic colorants in a pellet or grain that manufacturers form into plastic. Rather than adding a colored layer to the outside of a plastic product, concentrates make up the product.

To create a concentrate, a pigment is mixed with a polymer or carrier resin. For concentrates to work, the polymer must work with the base resin that the concentrate mixes with. The challenging aspect of concentrates is the lack of a universal polymer. Developers must identify the best polymer and base resin for production.

Is this banana yellow, or Nilla Wafer yellow? A spectrophotometer could tell. Image Credit: Flickr User: Travis Ekmark. (CC BY 2.0)

You have three hundred air conditioner housings in storage containers in the yard. “Sorry, we can’t take them,” says the client rep. “I personally feel like gray is gray, but I have to do things by the book. I know it’s a pain to rework, but the units have to meet specifications in order for me to accept them. Can you take care of it? Thanks.” She drives away, tires kicking rocks and dust, and there are still three hundred housings in the yard. Fishing your phone from your pocket, you dial. “Bill? We’re gonna need to do some rearranging.”

Not all purchasers of powder coated products are so picky about their colors; many clients are happy to choose from pre-mixed options or generic swatches. As a result, spectrophotometric analysis as a method of color quality control has not yet saturated the market. But for owners and operators of powder coating lines who are looking for a competitive edge, spectrophotometry represents a way to stand out while expanding your operations.

Color Precision Provides Opportunities for Powder Coating Lines

If you hope to take on clients with rigorous color quality control standards, spectrophotometric analysis is already essential since without this capability, you’ll be unable to compete for bids.1

And since powder coating is now being chosen over traditional liquid VOC paint due to its economic, environmental, mechanical, safety, and efficiency advantages,2 we’re seeing more and more applications that once used liquid paint beginning convert—including applications for a number of designer and specialty products. Companies like Austrian furniture designer Finima3 have already made the switch to powder coating, and winning bids for similar high-end applications will require you to have delicate control over product color—as well as the ability to offer unique color configurations.