On July 24, 1893, Worcester Envelope Company was incorporated with the purpose of “manufacturing and selling paper goods, stationery, and paper handling machinery.” Our legacy was made possible because of individual achievements in envelope manufacturing. From baking clay around tablets to wax sealing folded letters, the envelope specimen has finally been perfected because of the efficiency and consistency provided by this machinery. The first steps toward our craft occurred in 1845 when the British patent was awarded to Edwin Hill and Warren De La Rue for the invention of the first envelope-making machine and again in 1856 when Russell Howes’ machine could produce twenty-five thousand envelopes in just ten hours.

Our mission is to bring you high-quality envelopes. To understand how we do this, we have outlined the envelope manufacturing process into the following steps.

 

dreamstime_xxl_22334850How to Make Envelope Paper

  1. The most common method used to make wood into pulp for envelopes is called kraft pulping. Chips of wood are placed into a digester where a strong alkaline solution of sodium hydroxide and sodium sulfide are heated and pressurized for up to two hours.
  2. The pulp is then bleached to get rid of the brown wood pigments, also known as lignin. In general, bleaching involves mixing the pulp with a series of oxidizing chemicals that react with the lignin. After each mixture, the pulp is washed with a solution that removes the treated lignin.
  3. To give paper its brightness, opacity, and smoothness, fillers are added to the pulp. A typical filler is a clay known as kaolin and other chemicals that include various starches or gums. Sizers are then added to make the paper less absorbent.
  4. Then, the wood is mechanically or chemically processed and poured onto a mesh screen and squeezed through rollers to remove moisture. This forms sheets which are then moved through a series of heated cylinders that dry the paper.
  5. The sheets are then wound onto reels, spun dry if needed, and moved through rollers to make smooth.

 

Manufacturing Your Standard Business Envelope

  1. The machine performs all the operations needed to transform blanks into envelopes at a very rapid pace. Rolls of paper, typically weighing 220 lb, are either cut before they enter the automated machine, or fed directly into the machine from the roll.

    1. Once cut, the sheets are stacked and cut into what are known as blanks. A blank has the shape of an envelope with its flaps opened and laid flat. Blanks are generally shaped like diamonds and are cut from the sheets in such a way as to minimize waste.
    2. If the roll is fed directly into the machine, it cuts the paper into blanks very quickly with sharp blades. The machine also folds the blanks into envelopes at a very rapid pace.
  2. Strong glue is applied to the seams of the envelope and a weaker glue is applied to the top flap that will be sealed by the consumer.
  3. The machine then folds the blank to form the envelope. Windows are cut and transparent coverings are added as needed.
  4. The completed envelopes are placed into cardboard boxes and shipped to businesses.

Although modern envelope manufacturing is highly automated and results in a reliable product, we instill quality control procedures.We check for correct paper weight, shapes and sizes, adhesives, colors and printing, and overall structural integrity by inspecting samples of your envelopes designs. By checking these factors, we guarantee only the best versions of your envelope designs. With generations of experience, you can expect only the best at Worcester Envelope Company. Trust us with all of your envelope printing and manufacturing needs.