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What Is an 18 DIN Neck––and Why Should You Care?

by Steve Carow  |   Mar 1, 2018


Before the day of the Federal Drug Administration, medicines were sold street-side by shady wagon drivers. Ingredients as harmful as heroin, cocaine, and other narcotics were labeled as health supplements and cure-alls, without a single regulating standard.

Even foods were sold without regulation––which lead to an overuse of preservatives like borax and formaldehyde in milk and meat.

All of this led to a campaign against the lack of food and drug standards, which we all know evolved into the formation of the FDA. Imagine how our world might look if we lacked the administration’s standards!

Standards create a systematic method of mass production that saves time and ensures safety across the board.

Let’s take a look at one of the standards used in the bottling and packaging industry: the 18 DIN neck standard. This is the preferred bottle neck for essential oil bottles.

What Is 18 DIN?18-din

To understand the 18 DIN neck standard, start with the institution that developed this concept. The term DIN comes from Germany, meaning ‘Deutsches Institut für Normung.’ This translates as German Institute for Standardization.

The DIN is the industry standard for dropper bottles in Europe, just as the American Society for Testing and Materials (ASTM) is the standard here in the US. The DIN determines bottling standards for a variety of industries.

There are thousands of DIN numbers ranging from 1 DIN to DIN 79999. DIN standards are set for everything from dropper bottles to international paper sizes and German typeface for traffic signs.

18 DIN refers to the standard size of the neck, and an 18 DIN bottle is available in a range of sizes from 5 mL to 200 mL.

Using 18 DIN for Your Dropper Bottles

When you select the 18 DIN standard neck for your dropper bottle, this is the equivalent of an 18 GL standard neck. However, if you choose the 18 GL or glass bottle, this does not automatically feature a tamper-evident transfer ring. Yet this feature is available for this bottle type. Keep that in mind when making this selection and request this specifically if you need it for your product.

The benefits of using a dropper bottle with an 18 DIN neck starts with the design. This bottle is a standard size to mate with the cap without error. Since the bottle is made according to this standard, a transfer ring will fit and work properly when using the 18 DIN tamper-evident caps.

This saves you the hassle and worry of finding a well-designed dropper bottle that works successfully for dispensing product each and every time.

Additionally, the standard issue design ensures the neck finish features threads that are all the same diameter. As a result, the turns per centimeter are the same on all bottle necks, guaranteeing the neck opening is a standard size.

Even the wall thickness of the bottle neck is a standardized. Everything revolves around the standard of the DIN, which equates to smooth capping and cost savings.

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The 18 DIN standard neck for a dropper bottle also features a tamper-evident transfer ring. The transfer ring is part of the manufacturing process and can be made in a variety of ways. It is used to transfer the hot molded glass from station to station along the assembly line. You can utilize this transfer ring for either a tamper-evident or non-tamper-evident compatibility.

However, the 18 GL is not automatically tamper-evident as previously noted. If you select an 18 DIN, the transfer ring is designed at an angle that best fits the 18 DIN tamper-evident cap.

Additionally, the tamper band is retained when your consumer opens the bottle and reveals broken frangible––to identify the bottle has been opened.

Why Should I Use a Dropper Bottle for Essential Oils?

Branded buyers who are considering the use of a dropper bottle for essential oils need to keep a few things in mind. While the dropper bottle uses an 18 DIN neck, there are a few key issues to consider with using this type of packaging:

First, dropper bottles will have the overflow capacity that allows the application of a cap and dropper.

This insures that the bottle can be filled to the volume stated on the label and offer head space to avoid liquid compression

In addition, dropper bottles will have blow-back inside the bottle neck. The blow-back is a recessed area below the landing area of the bottle neck. The blow-back accepts a dropper and prevents the dropper from being squeezed out of the bottle when the consumer removes the cap.

As you can see, this would make it impossible for the consumer to dispense the essential oil using the disconnected dropper, which results in dissatisfied customers. However, your manufacturer needs to have special equipment in order to create the blow-back feature.

To Sum It Up

Choosing the 18 DIN neck design for your essential oil bottles offers substantial benefits. You do not have to reinvent the wheel with this neck size, which accommodates a cap and dropper perfectly.

You also save time and money with manufacturing the bottle, in addition to ensuring the satisfaction of essential oil consumers.

Standards matter––and, quite simple, they make life easier for purchasing buyers. To learn more or to request a sample of our compatible bottles and caps, contact Carow Packaging today.


Essential Oils

Steve Carow

Author: Steve Carow

Since 1993, Steve has developed a comprehensive knowledge of dispensing, including sales, operations, information technology, and product development, which he applies when identifying customer solutions. He is the President of Carow Packaging and our representative for Midwestern US & Central Canada Sales.



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