T-Shirt Day (T-Shatsu no Hi)

What Is T-Shirt Day?

Every July 20th is "T-Shirt Day," established by Fashion Mishimaya, a fashion company based in Nagoya, Aichi Prefecture. The date was chosen because "T" is the 20th letter of the alphabet, and because a T-shirt suits the national holiday "Marine Day," which was then held on July 20th. The idea is to treat the T-shirt as a canvas for self-expression and enjoy it more.

From Undershirt to Self-Expression

The T-shirt went through several turning points before becoming the everyday garment we know today.

• Roots as an undershirt: The T-shirt is said to have originated in the early 20th century as a cotton undershirt worn by soldiers and others. It spread after being adopted as an undershirt by organizations such as the U.S. Navy.
• Movie stars changed its image: In the 1950s, film stars such as Marlon Brando and James Dean wore the T-shirt — until then an undergarment — on its own. After this, the T-shirt was embraced as youth fashion.
• Popularity in Japan: In Japan, T-shirts became popular among young people in the 1970s as an affordable, casual way to wear the designs they liked.

Why T-Shirts Feel Comfortable in Summer

The properties of the fabric are part of why T-shirts are so useful in summer.

• Wicking sweat: Some polyester fibers used in performance T-shirts have specially shaped cross-sections, so sweat spreads through the gaps between fibers and dries more easily.
• Cooling through evaporation: When sweat evaporates from clothing it takes heat with it, which helps the body shed heat.

Interesting Facts About T-Shirts

• The name: It is called a T-shirt because it looks like the letter "T" when laid flat.
• Clothing that carries a message: From the 1960s onward, T-shirts printed with slogans and logos spread, becoming a way to show one's views and favorite things.
• Fabric weight in "ounces": T-shirt fabric thickness is often expressed as weight per square yard in ounces; the higher the number, the thicker the fabric. Heavier fabric is sturdy and less see-through, while lighter fabric is airy and breathable.
• Recycled materials: In recent years, more T-shirts are made with polyester recycled from plastic bottles and other sources.

Ideas for T-Shirt Day

• Pick your favorite T-shirt and wear it.
• Check the tags on your T-shirts and compare materials such as cotton and polyester.
• Ahead of midsummer, sort the T-shirts in your closet by color or shape.
• Carefully wash a white T-shirt and let it dry crisp in the sun.

Show Who You Are with One T-Shirt

July 20th is a day to appreciate a familiar garment loved around the world. What was once an undershirt has become a canvas for self-expression. Today, why not choose a T-shirt that feels truly comfortable and enjoy a summer day in it?