9H/10H hardness is a rating on the Pencil Hardness Test, commonly used by manufacturers of clear and pigmented surface coatings. The Pencil Hardness test is used to determine the scratch resistance of a coating surface by using pencils to scratch the surface and rate the scratch resistance in relation to that pencils hardness and other materials of similar hardness.  

Is the Pencil Hardness Test standardized

There are two different standards used in the pencil hardness test: ASTM D3363 and JIS K-5600-5-4.  Both require a different set of procedures and initial surface for coating to be applied to. This will allow various coatings, cured at different heats, to be tested without any other variables interfering.

The downfall with Pencil Hardness Test

The biggest concern with this testing method is the lack of control and standards.  Even when following a basic outline for standardized testing, different companies follow varied procedures that can skew the results of the hardness test.  One method is to lower the gram load weight of the pencil hardness tester.  The less pressure used in the tester, the less likely the surface is to scratch. This allows a tester to up the rating on their pencil hardness scale. This tactic is not outlined in the standardized testing, so it can go undetected by customers.  When choosing coatings based off the pencil hardness test, always look deeper into the testing methods as you are not always comparing “apples to apples.”

How does it apply to car paint protection coating?

Many brands boast 9H hardness, but you have to first know that the “H’ here is referring to pencil hardness, imagine using an array of pencils, small lines are drawn across the coating surface using graded pencils of increasing levels of hardness. No scratch is a pass and you move on to a harder grade. A standard pencil is graded at 2 HB in the US , a super hard technical drawing pencil is 7H, and the hardest is 10H. Coatings which are so hard that even the 10H pencil won’t scratch them receive a 10H rating to designate their hardness.

Is the coating force resistance?

Anything can be broken if it encounters enough force. However, EAD Diamond Foundation Coating are designed to increase your breakage resistance to an exceptional degree. Only the very hardest, most severe blows may damage your actual paint work. In some events or accidents, an EAD Diamond Foundation Coating will completely absorb the shock and perfectly protect your car surface – exactly as it was designed to do.

To make an enquiry about EA Detailer Paint Protection Coating service or find out more about how we can assist you further,

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