Seed: Enough Erasers for a Lifetime of Mistakes

This (top image) is unfortunately as much as you will see from the Seed factory as inside is strictly “no-photography”; but I will do my best to relay our experience visiting the original Osaka-based production plant a few years back. Nevertheless I have included a few shots from the company brochure which give a flavour of eraser making - not dissimilar to baking seemingly, though not an invitation to eat any!

 Like for many suppliers, we have a special place in our heart (and assortment) for the “first’s”, and Seed is responsible for the world’s very first vinyl chloride, or plastic, eraser patented and commercialised under the trademark “Radar” in 1955. If you can reminisce and consider the wonder that cute, perfumed, food shaped erasers impressed onto a 6 year old circa 1986, then you will understand that such a company has made a significant cultural contribution to the world worth gushing about. It is also a silent and humble stationery protagonist, discreetly producing, some of the worlds most infamous erasers - notably Tombow’s Mono, under private label (Seed produces over 80% of erasers for the Japanese market, but mostly unknown to the average Japanese consumer) 

 To give some context, let’s discuss early eraser production. Before industrialisation, there was no broad demand for erasers. Specifically in Japan, for cultural reasons also, ink and brushes were the main writing supplies and only in the latter part of the 19th, when political mandates for universal education cropped up worldwide, did modern-day stationery supplies become household items. Intrinsically tied to the consumption of pencils, it is not surprising that erasers were mainly imported from Germany, then already a stationery powerhouse (think Faber and Staedtler). Domestic production of erasers in Japan was a small side line to transforming rubber into other consumables such as boots, hoses, tubes, rubber bands …  

Natural rubber raw materials were unreliable to source and prone to price fluctuations; but the production was encouraged domestically as WWI restricted imports from Europe. With the advent of plastics, the new material demonstrated some obvious advantages: odourless, more stable to store, without hardening, and generally more performant - Seed wasn't blind to this opportunity and in 1950, originally known as the Miki Kosaku Rubber Co., the company changed its name and relaunched itself as a plastic eraser-only producing manufacturer focusing on its new patented invention. 


This was not an overnight success as natural rubber erasers dominated the market well into the late 60s and even early 70s. Eventually, as we regrettably know today, plastics did take over and penetrate every aspect of our day-to-day tools and consumables. The 80s saw no limit to the colours and scents which could be added to add excitement to children’s school supplies (and boost sales!) 

Thankfully the Radar eraser is faithful to its original 1955 inception design, resisted embellishment, conservatively functional - simply a white block, with a 97% erasing capability, cased in its graphically punchy blue packaging. 

How are Seed’s erasers made?

1. The raw materials to produce the PVA are weighed and mixed together in machine like a giant blender.
2. The mix is stirred, heated and “cooked” until it reaches the right texture and softness/hardness - any colours or scents would also be added at this stage if applicable.

3. While still in a liquid form, the plastic is poured into a bloc shaped mould and then pressed down to make a very large sheet of eraser
4. Alternatively the liquid form plastic is poured into an injection mould machine to create core detailed and complex shapes. Long circular erasers can be created in a similar way using an extrusion moulding machine - this is very cool to watch !
5. A cutting machine will cut the erasers to size. With rectangular standard erasers this is performed to a high degree of precision and very satisfyingly so for anyone with an OCD disposition.
6. Finally, the erasers are cased in their holding sleeve (to keep them from fusing with other plastic objects they might come in contact with) and packaged in cellophane. This is done on a small conveyor belt which seems reasonably antiquated but very efficient still. 

Thanks to Seed for image resources