Science

drawing of two men dragging sleds across snowy landscape wearing wool clothing
5 Times Wool Clothing Saved Someone's Life
From open bivouacs in Everest's Death Zone to battlefield flash fires and unsupported polar crossings, tales of extreme survival feature these recurring heroes: wool clothing and Merino wool clothing.  The... Read more...
a drawing of a merino sheep
What is Merino Wool? The Science Behind the Performance
Table of Contents 1. Historical Origin and Breed Development 2. Fiber Structure and Molecular Composition 3. Thermodynamic Performance and Apparel Comfort 4. Odor Suppression and Skin Health 5. Fiber Fineness,... Read more...
A black and white vintage-style drawing diagramming the human toroidal field, a donut-shaped magnetic field generated by the human heart
Human Toroidal Field: The Science
A dive into scientific research illuminating the human toroidal field, a measurable and dynamic field emanating from the human heart. Read more...
An infographic distinguishing the manufacturing process of combed cotton, also showing the positive properties of combed cotton, especially as those benefits pertain to the kind of printed shirts sold at ShirtCastle
Combed Cotton Explained
Only the longest, strongest, and most uniform cotton strands, perfectly aligned in one direction. Read more...
A black and white. infographic showing the process and science behind ring-spun cotton versus conventional cotton
Ring-Spun Cotton Explained
Unlike standard open-end cotton, which is formed by loosely collecting and entangling fibers using centrifugal force, the ring-spinning process meticulously aligns the cotton strands in a uniform helical arrangement, trapping... Read more...
a woman breaking flax in russia
Linen Is a Natural Fiber & Has Been Used for 30,000 Years
Linen is a natural fiber! Stay tuned for linen products in the future at ShirtCastle™. Read more...
A black and white ShirtCastle infographic depicting the science of Nylon microplastics releasing chemicals in the lungs that genetically inhibit proper cell growth
Nylon Is a 100% Synthetic Fiber
Nylon was a scientific breakthrough. But today we know synthetic textiles pose risks to human health, and some of the research around Nylon is especially worrisome.  Read more...
a black and white infographic describing Lyocell's manufacturing and properties
Why Tencel (Lyocell) Is Not a Natural Fiber
Is Tencel (Lyocell) a Natural Fiber? No, Tencel (Lyocell) is not a natural fiber. It is technically classified as a semi-synthetic or regenerated cellulosic fiber. While it is derived from... Read more...
Why Modal Is Not a Natural Fiber
Why Modal Is Not a Natural Fiber
The definitive, researched answer to the question "Is Modal a Natural Fiber?" Read more...
An old postcard shows an aerial view of a viscose manufacturing plant in virginia
Why Viscose Is Not a Natural Fiber
Viscose is not a natural fiber, so you won't find it at ShirtCastle™. But you will find us nerding out on the fiber science.  Read more...
black and white infographic about rayon
Why Rayon Is Not a Natural Fiber
Rayon is not natural fiber, so you won't find it at ShirtCastle. But you will find this scientific deep dive on the fiber science. Read more...
A black and white line-drawing infographic about polyester clothing shedding microplastics into indoor air and contaminating the human body
Microplastics, Polyester Clothing & Human Health
Table of Contents What Are Microplastics? Polyester: A Leading Source of Microplastic Exposure How Microplastics Enter the Human Body Microplastics in Brain & Where Else They Have Been Detected What... Read more...