kuverts

Kuvert is a flat, foldable paper container used to enclose letters or documents for postal delivery. Most kuvert have an opening at one end and a sealing flap. They may be moistened and sealed or self-adhesive. Some kuvert feature a transparent window to display the recipient address, while others are windowless for privacy. In addition to standard paper, there are padded kuvert with a foam or bubble lining for fragile contents.

History: The envelope as a dedicated container developed with the growth of organized postal services. Before machines, letters were folded and sealed with wax or tape. In the 19th century, machine-made kuvert with gummed flaps enabled faster production and postal handling. Self-adhesive variants were introduced in the 20th century and are common today.

Sizes and types: Common sizes align with international standards, including DL (110 × 220 mm), C5 (162 × 229 mm), and C4 (229 × 324 mm). The choice depends on the size of the document. Other types include business, greeting, reply, and security kuvert. Materials range from white office paper to kraft, recycled, and specialty finishes.

Environment and handling: Many kuvert are recyclable; window envelopes use plastic windows that may affect recycling. Some jurisdictions require removal of windows before recycling. Designers consider tape, glue, and ink. In modern mail, digital communications reduce demand, but kuvert remain essential for physical correspondence, legal notices, and packaging.