Blow Molding, the Black Art

Blow Molding, the Black Art

Blow Molding used in plastic bottle manufacturing

In this article we will cover:
The history of Blow Molding,
What is Blow Molding?, and
What can be manufactured through Blow Molding?

The history of Blow Molding

When you think of “Black Art” it reminds you of dark alleyways, shady deals and secret ingredients. Or maybe old traditions and practices used long ago that have since been lost due to new and clean technological advances. You may even think of a mysterious process that no one really knows anything about and that is not very advanced. Leave those thoughts and ideas behind and come explore the highly advanced art of blow molding today.
Blow molding is not done behind closed secret doors or in the dark. Blow molding is a highly technical manufacturing process that has been developed over many years. It has long been brought out of the dark and is used in manufacturing and industry throughout the world.
Blow molding was first developed by a couple of men who took the idea of glass blowing techniques to a new level. They developed and designed blow molding production machinery. The first blow molding machine was sold in the late 1830’s. Unfortunately the process did not catch on until many years later.
Today blow molding is a competitive and integral part of the manufacturing process where billions of dollars are spent and billions of plastic bottles are produced. The blow molded bottles and parts produced are used in nearly all types of industry.

What is Blow Molding?

So what is blow molding? Blow molding is a highly developed technical manufacturing process where plastic is used and molded into hollow bottles or parts. There are three main types of blow molding. Extrusion blow molding, injection blow molding and injection stretch blow molding.
In injection blow molding, a mold is made to specification for the part. Plastic is then melted and formed into a small test tube like form called a parison. The parison is put into the mold and pressurized air is forced into the middle of the parison. The air pushes the plastic from the parison out into all the recesses of the mold. After the plastic has cooled, the mold is opened and the plastic bottle or part is removed.
By forming bottles and parts with injection molding there are no bubbles in the plastic. Once the bottles are formed, they can be tested for leakage before being sent out for product filling.

What can be manufactured through Blow Molding?

Today almost all major industries from medicine to food production, personal care products and the auto industry, use blow molding to make the bottles and parts for their products. Blow molding is used for medicinal containers, soft drink bottles, bottles for cleaners and soaps, containers for makeup and creams, food containers, auto parts and garden tools.
Using blow molding, packaging bottles can be produced using many different types of materials and colors and formed into many different shapes. And the colors, materials and shapes available through blow molding are much more diverse than what is available with traditional metal options.
Additionally, through the blow molding process, bottles and parts can be manufactured in high volume at a reasonable price and in a very timely manner.

At Design-Tek Tool and Plastics Inc., our professional engineers and designers can help you take the “black” out of the art of blow molding. It takes a lot of know how to do blow molding well and to do blow molding right. At Design-Tek our experience and in house engineering and machine shop help us keep up to date in the advanced field of blow molding and ensure that we service our machines properly and promptly. We want to meet your needs in an efficient, cost effective and timely manner. Currently, at Design-Tek, we have the capacity to produce blow molded bottles in the smaller range sizes from 4 oz. up to 20 oz. bottles.
Let our experts at Design-Tek assist you in making your product better and faster with blow molding. Even if you do not have a finished, shelf ready product, and are still in the research and development phase, Design-Tek can assist you with production and manufacturing ideas for your creation and help you to make it better.
At Design-Tek we want to help bring your product out of the dark.
Please contact us at or 801-393-4400 for more information and a free price quote.