A Do-maru is a traditional Japanese coat of armor dating back to the late Heian period (794-1185). It is characterized by its wrapping style, designed to encircle the body, providing flexible protection for martial arts or the battlefield. The Do-maru is crafted from small scales or plates of iron or leather, laced together with silk or leather cords. It differs from similar armors like the O-yoroi, as it was lighter and allowed greater mobility, making it favored by samurai of lower rank or foot soldiers. The design encompasses a tight fit around the torso, extending to cover the hips, with sleeves to protect the arms. Variations over time have added features like sode (shoulder guards) and kusazuri (a skirt of plates) for enhanced defense. Its significance goes beyond mere military utility, extending into cultural symbolism, representing the warrior spirit and aesthetic of feudal Japan.

DMSO (Dimethyl Sulfoxide) is known for its powerful solvent properties, capable of dissolving a wide array of organic compounds and some polymers. However, polypropylene, a thermoplastic polymer widely used in various applications due to its resistance to many chemical solvents, acids, and bases, is not readily dissolved by DMSO. This resistance is due to polypropylene's non-polar nature and its semi-crystalline structure, which makes it less susceptible to interaction with polar solvents like DMSO. While DMSO may slightly swell some types of polypropylene, it does not dissolve it in the way it does with more polar polymers or simpler organic compounds.

Resin can go "bad" or become unusable over time due to various factors including exposure to heat, moisture, or improper storage. Epoxy resins, for instance, are more susceptible to these issues and may become thick, clumpy, or cure improperly if stored or handled incorrectly. The shelf life of resin can vary depending on the type and brand but is generally around 12 months from the manufacture date if unopened and stored properly. Once opened, it's best to use the resin within six months to ensure optimal performance. To extend its shelf life, always store resin in a cool, dry place and tightly seal the containers to prevent exposure to air and moisture. If your resin has changed in texture or smells odd, it's likely compromised and should not be used for your projects.