Hot Stamp Molds, Heat Transfer Molds: What Are They? What To Look For?

How Molds Are Used to Create Silicone Hot Stamp and Heat Transfer Stamping Dies

What questions do customers often have about Molds?

Building Molds is part of the process of manufacturing Silicone Dies used for Hot Stamping and Heat Transfer applications.  Because Molds are part of the production process which happens behind the scenes rather than the physical product delivered to our customers, Molds tend to be something that customers are not familiar with.

Common questions we hear are:
1. What is a mold?
2. Why are molds needed?
3. What types of molds are available?
4. How does United Silicone store mold? 

What is a mold ?

A good place to start in answering these  questions is at the beginning… what is a Mold?

A mold is actually the “BOX” or Tool that holds and forms the silicone compound or raw material into a graphic design ultimately resulting in a finished, Silicone Die.


Another way to think about this is to consider the Mold similar to that of a cake pan!  Just as a cake pan or muffin tin forms batter into a desired shape, a Mold does the same – enabling silicone to flow into the various design features resulting in a Hot Stamp Die replicating your artwork or graphic image.  .

Instead of a cake, the result of this molding process is a Silicone Die!


Why are molds needed?

In addition to serving as the “box” or “cake pan” the die is created from, the Mold plays an important role in artwork orientation.

For a Die to stamp your desired artwork the way you wish it to appear on your part, the artwork on the face of a Silicone Die will appear “Read Wrong” or backwards in order for the final stamped image to read correctly or ‘read right’!  The Mold is part of this process. A Read RIGHT mold creates a Read WRONG die which in turn creates a Read RIGHT image termed as ‘First Surface’ decoration.


What types of molds are available?

There are two types of Molds or Tools used to manufacture Silicone Rubber Dies – Photo-etched and Machine Engraved.   Photo-etched Molds can be defined as “soft molds” or “make-readies” while Machine Engraved Molds are defined as “hard molds” or “CNC-engraved tools”. Let´s take a look at the benefits provided by each.

Make Readies (Soft Molds)

Photo-etched or ‘Soft’ Molds are made utilizing a chemical bath process. The main benefits of Photo-etched Molds or Make-readies are that they can be manufactured and shipped quickly while being cost-effective.  Also, textured surfaces can be incorporated into this Mold style assisting with the elimination of air entrapment during hot stamp and heat transfer applications.

Machine Engraved (Hard Molds)

Machine Engraved or “Hard” molds are made with the CNC engraving process. While these Molds are more costly than Photo-etched Molds, there are 3 instances where Machine Engraved Molds should be considered to deliver superior quality decoration.

First – unlike Photo-etched or “PE” Molds and Dies, Machine Engraved or “ME” Molds and Dies can be manufactured with multiple reliefs.

When should machine engraved (hard) molds be considered?

Case 1: When Multiple Reliefs are Required

First – unlike Photo-etched or “PE” Molds and Dies, Machine Engraved or “ME” Molds and Dies can be manufactured with multiple reliefs.

What is Relief in the context of Dies; what does it mean?!  Relief is the height the graphics are elevated from the background of the Die itself.  The most vulnerable graphic elements or finest details can be placed at a lower relief for enhanced support and protection.

Photo-etched Molds produce Dies with only 1 relief or stamp height. Machine Engraved Molds enable the creation of Dies with multiple reliefs. This gives strength to fine graphics and helps eliminate overstamping of large, bold designs. What’s more, the ability to stamp graphics at multiple heights with a single Die avoids the need for additional set ups, simplifying the overall production process.

Finally, Crowns and Contours can be designed into Machine Engraved Molds and Dies to assist with complete die-to-part contact over curved or non-flat part or product formats.

Case 2: When Vertical Side Walls are Required

A second instance where Machine Engraved or “ME” Molds may provide superior results is when vertical sidewalls are required for part clearance and/or for precision foil transfer of lines or characters. Hard or CNC machine engraved molds provide this ‘control’.  Near vertical side walls facilitate crisp, sharp edges of your decoration as well as precision alignment to the contour or shape of a part.

Case 3: When High Precision Repeatability is Required

Finally, Silicone Dies from Machine Engraved or “Hard” Molds are highly accurate and repeatable from Die-to-Die. For example – a Die used to stamp the lines of a ruler or another measuring device (like the cup shown here) must  create a finished part accurate to that scale of measurement.  In other words, a hot stamped ruler must actually measure 12 inches NOT 11 and 7/8!  As Dies wear out and require replacement- a Machine Engraved, Hard Mold will ensure measurements remain precise and highly repeatable die-after-die and stamp-after-stamp.

Will I receive a mold with my order?

Because the process used to manufacture Molds is confidential/proprietary and because Molds are the ‘Tooling Set-up’ required as part of the Silicone Die production process (and not a finished product) – Molds are NOT released or shipped to our customers but rather are maintained as inventory at United Silicone.

How long will United Silicone store my mold? What keeps competitors from being able to access my molds?

There are two questions we are commonly asked about mold storage protocols:

First  – How long will United Silicone keep my Molds?
The answer is up to 5 years without purchase activity. That is to say, we will store a mold for 5 years with no Dies being ordered throughout that time period. If new Dies are made from a specific mold at least once every 5 years, United Silicone will hold that mold as ‘active’ indefinitely.

Second  – What prevents my competitors from being able to order Dies from my Molds?
The answer is simple! United Silicone issues a unique identifier or part number to each Mold and Die produced. This Die Number tracks ownership back to the original buyer. No one can order Dies from that Mold without written permission on company letterhead from the original owner. We do receive requests – particularly from users who have outsourced their decoration processes allowing their suppliers to order Dies from their Molds. As long as this request comes in writing on official company letterhead, United Silicone will make Dies happen!


Would you like to know more?

Please get in touch. We would love to hear from you.