Rapha board

What is rapha board?


This is the product of our company manufactured with the light weight processed material with unique characteristic which is created following the formation of numerous fine air bubbles in the particles when the organic substance which is rapidly produced while the lava created from volcano activity is contacted with water and the perlite with grey or blue color containing 3~5% crystallization water and the additional perlite among pitchstone and obsidian are processed, and then, rapidly heated with the temperature of more than 870 degrees for evaporating the internal crystallization water. 



Quarry stone








Production facility




Chemical composition

Composition SiO2 Al2 O3 K2 O Na2 O Fe2 O3 Ca2O MgO
Containing ratio 72~78 10~15 2.5~4.5 2.5~4.5 0.2~1.2 0.1~0.5 0.1~0.3



Product construction (Gallery)





Doosan Infra Core (Kunjang Industrial Complex)



Hankook Musical Institute (Jongno Sajic)



CCC Studio (Ilsan Baekseok)



Cheongju Airport (Smoking room)


Cheongju Airport (Wall)


Cheongju Airport (Inside)


Hallym Care Hospital


Hallym Care Hospital (Wall)


Dreaming Church


Dreaming Church


Dreaming Church



Characteristics of rapha board



Light weight

This is the super lightweight product whose weight compared to volume is very small by containing numerous air bubbles of 0.03~0.25g/cm per unit volume and construction weight can be reduced when it is used as building material and the specific gravity of applied product can also be lowered.




This is the product which is manufactured by burning with chemically neutral (ph 6.5~7.5) nonflammable inorganic combination and it is the product which does not produce any toxic gas at all at the time of fire, and it is the material which is approved as food additive and is utilized as soil conditioner. 



insulation property

As the extraordinarily porous particles with the thermal conductivity of 0.03~0.05Kcal/mh, its internal solid conduction is very low since it is connected with point contact between particles and not only it prevents the convection because minute particles are charged at the cavities but also its insulation property in relation to the radiation is simply superb.




As a mineral of natural inorganic material, it is nonflammable material which does not generate any toxic gas even at high temperature and the range of application temperature is -250~1,000 degrees and its application range of insulation is wider than any other competitive materials.



sound absorbing property

This is the porous material with excellent sound-proof characteristic and it has the sound absorption coefficient of more than NRC 0.7 in accordance with the sound direction and burning condition and the forming can be conducted into acoustical shape, and in that case, even the sound absorption coefficient of more than NRC 0.9 can be accomplished. 




As the moisture of up to 87% of its own weight can be contained, it has the function of adjusting the humidity within the constructed space by discharging the moisture during the dry climate and absorbing the moisture during the wet climate. .



Application field (Use)

  • Building materials – Ceiling material, interior material, partition material, and insulation
  • Acoustic facilities – Theater, auditorium, conference hall, gymnasium, and swimming pool
  • Industrial field – Vessel interior panel, industrial plant, sound-proof for factory, and sound-proof for industrial equipment
  • Environmental field – Water quality improvement sector, deodorant for industry/household, and filter for industry


Introduction of product _ Hanmaek CC Golftel (Yecheon)


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