Many of us must have come across the situation when our pen must have leaked and made the clothing colourful. It is a common incident but have you ever thought, why does it happen? The gel pens are filled with fluid called gel. It is thick and opaque in texture. It needs a barrier to hold its flow. In this article, we are going to throw light on the topic which will talk about the Silicone content present in gel pens refills. It is called the follower or stopper fluid. It helps to hold the gel, not to let it come out of the refill.
Introduction to gel pens
Gel pens are the most demanded product in the market because of their smooth flow of writing. It was manufactured in Japan in 1980 for the first time. Copper phthalocyanine and iron oxides are the substances used to form gels. It is usually filled up in a barrel-like structure. The gel ink is in the front of the barrel and the transparent substance protects it at the end. The gel ink is viscous by nature but its thickness is not enough to prevent it from getting leaked. It can get evaporated over time, the follower acts as a seal, not to let it evaporate.
Introduction to stopper fluid
The ink present in the gel pens is of low viscosity. It is made up of pigmented water-based substances. There are chances that it may get evaporated or it may get leaked due to water-based fluids. It needs to be supported by some fluids which can work as a stopper. Such fluids are called ‘stopper fluid’. It is a kind of Silicone Gel. It performs a task of grease.
Functions of Silicone present in stopper fluid
You must have noticed the smooth flow of gel pens as compared to ballpoint pens. It happens due to such silicone fluids present in the refills. It acts like a weight on the gel fluid in the refill. It is firmly arranged in the refill so that it does not get evaporated. It acts as a stopper fluid for the water-based substance in the refill.
The problem of leaking out happens due to the evaporation of water in the gel. The grease-based substance present at the end of the gel pen has the capacity to hold that fluid. The follower or the stopper is used to prevent the pen from getting dried up or getting leaked. The formation of such stopper fluids is done in order to make better quality gel pens.
Formation of stopper fluid (Follower)
This follower is made up of some oil-based substance or grease. Alone grease can’t help to retain the flow. Some thickeners are added to it. The combination of grease and thickeners make a way for the production of stopper fluids. Every manufacturer is having its own process of manufacturing stopper fluid but in general terms, Dimethyl Silicone oil or alkyl- modified silicone oil is used to produce this substance. This fluid acts like a barrier for the gel ink and the best part are that it does not get dissolved with the gel ink. It is a transparent substance that stays at the end of the gel barrel in the pen. It is equipped with a non-polar material which allows it, not to get mixed with gel. The basic properties of silicone are used to have a grip on the gel. Silicone is a substance that is not so thick and not so smooth. It is present at the end in a transparent form.
The ink follower or in other words, stopper fluid is always used at a value of 25 to 50 mm, at 20 c. If the value gets lesser than 25 mm, then it would become too hard to follow the gel. If the minute value is greater than 50mm, then it would be too soft and would not be able to prevent the gel from getting leaked. It has to be heated on the exact described values. It is very important to know the texture of the follower. A spread meter can be used to know the hardness or the flow of the stopper fluid(follower).
Conclusion
The grease or silicone substance is used to make a transparent fluid. It is called the follower or stopper fluid. This substance is present at the end of the gel pen. It performs the task of a barrier to prevent the gel from getting evaporate or leaked. This transparent fluid plays a vital role in the functioning of the gel pens. It can be held at one position and it does not move backwards or it does not get dissolved with the gel.
We are sure that the readers must be well equipped with knowledge about the gel pens and the stopper fluid. Keep on reading our articles and explore the interesting facts with us. We are looking forward to our readers’ feedback. Get in touch with us. Keep on expressing and keep on exploring.