Masterbatch pellet mixture

A masterbatch pellet mixture comprising a mixture of a high specific gravity masterbatch pellets group (A) with specific gravity within a range from 1.8 to 3.5, and a low specific gravity masterbatch pellets group (B) with specific gravity within a range from 0.5 to 1.6, wherein the high specific gravity masterbatch pellets group (A) comprises m different columnar masterbatch pellets from type 1 through to type m, each with a different specific gravity, the low specific gravity masterbatch pellets group (B) comprises n different columnar masterbatch pellets from type 1 through to type n, each with a different specific gravity, and the high specific gravity masterbatch pellets group (A) and the low specific gravity masterbatch pellets group (B) satisfy a formula (1) shown below:

• 0.5
• ⁢
• ⁢
• (
• mm
• -
• 1
• )
• ≦
• ∑
• p
• =
• 1
• m
• ⁢
• (
• Hp
• Sp
• ×
• Rp
• )
• -
• ∑
• q
• =
• 1
• n
• ⁢
• (
• Hq
• Sq
• ×
• Rq
• )
• ≦
• 12
• ⁢
• ⁢
• (
• mm
• -
• 1
• )
• ⁢
• .
• (
• 1
• )
• wherein symbols in the formula are defined as follows:
• m:
• an integer from 1 to 10
• n:
• an integer from 1 to 10
• p:
• a type number of columnar masterbatch pellets within the high specific gravity masterbatch pellets group (A)
• q:
• a type number of columnar masterbatch pellets within the low specific gravity masterbatch pellets group (B)
• Hp:
• a height (mm) of columnar masterbatch pellets of type p within the high specific gravity masterbatch pellets group (A)
• Sp:
• a bottom surface area (mm2) of columnar masterbatch pellets of type p within the high specific gravity masterbatch pellets group (A)
• Rp:
• a mass proportion of the mass of the type p columnar masterbatch pellets relative to a total mass of the high specific gravity masterbatch pellets group (A)
• Hq:
• a height (mm) of columnar masterbatch pellets of type q within the low specific gravity masterbatch pellets group (B)
• Sq:
• a bottom surface area (mm2) of columnar masterbatch pellets of type q within the low specific gravity masterbatch pellets group (B)
• Rq:
• a mass proportion of the mass of the type q columnar masterbatch pellets relative to a total mass of the low specific gravity masterbatch pellets group (B).