Volcanic Glass D.B. Properties

Hollow micro-spheres are used as lightweight filler or increase material for building material, paints, heat insulator and plastic. Moreover, this materials contribute for saving of resource and energy.

These hollow micro-spheres are produced from the inorganic material or the organic material. In the case of the inorganic materials, it can be use a natural raw material such as volcanic glass in the pyroclastic deposit or artificial raw materials such as SiO₂-B₂O₃ glass or alumina. In the case of the natural raw materials, Shirasu-balloons can be produced. In another cases of artificial raw materials, the glass-micro-balloons or the alumina-bubbles can be produced. Moreover, the phenol balloons etc. are producing as hollow micro-spheres of an organic quality.

The patent for producing of Shirasu-balloons was applied in 1970, and was registered in 1974 . Industrialization of Shirasu-balloons was successful in 1971. Afterwards, the amount of production was increased smoothly.

A lot of brands are being produced by 10 companies now. And, the amount of all production is about 20,000 tons of 1/10 of the amounts of the presumption production of the perlite of similar materials.

Recently, production or development of micro Shirasu-balloons with mean diameter smaller than 50 microns or less was done by each company. Expansion of the market of this micro Shirasu-balloons can be expected in the future.

A sectional meeting in Japan Society of VSI (Volcano Silicates Industry) for developing and evaluating of micro Shirasu-balloons was started in 1997, and physical properties of the micro Shirasu-balloons 15 samples (No.B-1-1~B-7-2) which is producing or developing in member each company were measured. Moreover, physical properties of comparison 9 samples (No.B-8-1~B-8-9) that is made from SiO₂-B₂O₃ glass were measured.

Micro Shirasu-balloons	B-1-1	B-1-2	B-1-3	B-2-1	B-3-1	B-3-2	B-4-1	B-4-2
Micro Shirasu-balloons	B-5-1	B-5-2	B-5-3	B-5-4	B-6-1	B-7-1	B-7-2
Comparison samples	B-8-1	B-8-2	B-8-3	B-8-4	B-8-5	B-8-6	B-8-7	B-8-8	B-8-9

Last updated: September 2001
A lot of brands are being produced in each company besides 15 samples that have been opened in this database.

	List of companies or reseach institute that supplied samples
	Method of measuring physical properties
Summary of Results
	Particle size distributions
	Colors and whiteness
	Mean diameter, Amount of particles floating in water and density
	Strength
	Heatproof temperature

Particle size distributions of micro Shirasu-balloons of producing or developing (wt%, under).

No.	5µm	6µm	8µm	10µm	15µm	20µm	25µm	30µm	40µm	45µm	Mean diameter (µm)
B-1-1	2.5	4.3	8.4	12.8	25.8	41.7	55.7	69.2	88.2	92.6	23.0
B-1-2	2.3	3.6	6.7	10.6	23.1	38.2	52.4	66.4	89.5	95.0	24.2
B-1-3	1.0	1.5	2.1	2.6	10.7	14.9	22.5	31.1	55.2	60.7	37.8
B-2-1	3.6	4.9	7.4	10.5	19.1	30.1	41.2	52.1	71.2	75.7	29.0
B-3-1	1.6	1.9	2.5	3.8	9.2	13.0	18.2	23.9	37.6	40.9	50.0
B-3-2	1.7	2.7	5.2	8.9	16.9	28.0	37.8	47.3	73.2	79.2	31.0
B-4-1	3.3	5.7	10.8	15.1	31.8	49.1	63.2	76.2	95.3	100.0	20.3
B-4-2	1.9	2.8	5.4	10.7	43.7	72.9	85.6	93.6	98.5	100.0	16.1
B-5-1	8.0	12.0	20.9	30.0	55.3	73.1	82.9	90.3	97.8	100.0	14.0
B-5-2	4.6	7.1	12.6	18.2	36.2	52.3	65.5	77.7	94.3	98.5	19.3
B-5-3	2.2	2.3	3.5	7.1	17.4	28.0	42.0	56.9	77.9	83.0	27.7
B-5-4	5.5	7.6	12.6	17.8	37.1	55.0	67.8	78.8	93.0	96.7	18.6
B-6-1	1.5	2.7	6.1	10.1	26.2	42.8	57.8	72.3	94.4	99.8	22.4
B-7-1	11.2	16.3	26.4	36.8	66.5	85.5	92.1	95.2	98.7	100.0	12.2
B-7-2	11.3	16.0	25.8	35.6	65.3	84.1	91.3	95.3	98.7	100.0	12.4

Particle size distributions of comparison sample from SiO₂-B₂O₃ glass (wt%, under).

No. 5µm 6µm 8µm 10µm 15µm 20µm 25µm 30µm 40µm 45µm Mean diameter (µm)
B-8-1 10.1 15.6 27.7 39.4 67.4 83.0 89.9 94.3 98.5 100.0 11.9
B-8-2 - 0.7 2.6 4.5 7.8 19.4 30.3 40.9 63.0 98.2 34.1
B-8-3 - 0.9 1.6 3.9 11.4 19.0 31.0 44.6 69.3 75.0 32.2
B-8-4 - - - - 2.8 13.5 25.3 37.5 56.4 60.6 36.6
B-8-5 - 1.2 3.7 8.0 15.3 27.5 40.2 55.5 91.7 95.9 28.2
B-8-6 - - 1.3 3.1 8.8 11.6 20.2 30.6 62.0 69.2 36.2
B-8-7 - - 3.1 7.2 14.5 24.9 36.9 49.5 81.7 89.2 30.2
B-8-8 - - 2.1 5.2 14.9 23.0 37.3 53.5 86.2 94.1 28.9
B-8-9 - 1.0 3.2 7.5 14.4 23.7 38.8 55.6 91.3 99.6 28.3

No.	5µm	6µm	8µm	10µm	15µm	20µm	25µm	30µm	40µm	45µm	Mean diameter (µm)
B-8-1	10.1	15.6	27.7	39.4	67.4	83.0	89.9	94.3	98.5	100.0	11.9
B-8-2	-	0.7	2.6	4.5	7.8	19.4	30.3	40.9	63.0	98.2	34.1
B-8-3	-	0.9	1.6	3.9	11.4	19.0	31.0	44.6	69.3	75.0	32.2
B-8-4	-	-	-	-	2.8	13.5	25.3	37.5	56.4	60.6	36.6
B-8-5	-	1.2	3.7	8.0	15.3	27.5	40.2	55.5	91.7	95.9	28.2
B-8-6	-	-	1.3	3.1	8.8	11.6	20.2	30.6	62.0	69.2	36.2
B-8-7	-	-	3.1	7.2	14.5	24.9	36.9	49.5	81.7	89.2	30.2
B-8-8	-	-	2.1	5.2	14.9	23.0	37.3	53.5	86.2	94.1	28.9
B-8-9	-	1.0	3.2	7.5	14.4	23.7	38.8	55.6	91.3	99.6	28.3

Colors and whiteness of micro Shirasu-balloons of producing or developing.

No. L a b Whiteness (Lab) Whiteness (Hunter)
B-1-1 81.70 2.22 11.11 78.47 53.78
B-1-2 81.71 2.13 9.57 79.24 55.58
B-1-3 75.16 2.84 11.69 72.39 43.93
B-2-1 81.66 1.68 9.35 79.35 55.78
B-3-1 77.79 2.52 10.84 75.15 48.46
B-3-2 76.80 2.40 10.97 74.23 46.95
B-4-1 77.68 3.58 13.08 73.89 45.83
B-4-2 86.75 1.12 5.30 85.68 68.68
B-5-1 87.08 2.06 9.55 83.81 63.96
B-5-2 85.79 1.92 9.49 82.81 61.98
B-5-3 85.99 1.68 9.01 83.26 62.87
B-5-4 84.91 1.90 8.58 82.54 61.69
B-6-1 82.04 3.18 10.09 79.16 55.48
B-7-1 89.54 1.17 5.10 88.31 73.66
B-7-2 89.84 1.02 4.73 88.75 74.65

No.	L	a	b	Whiteness (Lab)	Whiteness (Hunter)
B-1-1	81.70	2.22	11.11	78.47	53.78
B-1-2	81.71	2.13	9.57	79.24	55.58
B-1-3	75.16	2.84	11.69	72.39	43.93
B-2-1	81.66	1.68	9.35	79.35	55.78
B-3-1	77.79	2.52	10.84	75.15	48.46
B-3-2	76.80	2.40	10.97	74.23	46.95
B-4-1	77.68	3.58	13.08	73.89	45.83
B-4-2	86.75	1.12	5.30	85.68	68.68
B-5-1	87.08	2.06	9.55	83.81	63.96
B-5-2	85.79	1.92	9.49	82.81	61.98
B-5-3	85.99	1.68	9.01	83.26	62.87
B-5-4	84.91	1.90	8.58	82.54	61.69
B-6-1	82.04	3.18	10.09	79.16	55.48
B-7-1	89.54	1.17	5.10	88.31	73.66
B-7-2	89.84	1.02	4.73	88.75	74.65

Colors and whiteness of comparison sample from SiO₂-B₂O₃ glass.

No. L a b Whiteness (Lab) Whiteness (Hunter)
B-8-1 95.61 0.94 0.62 95.47 90.57
B-8-2 93.45 0.74 1.68 93.19 85.08
B-8-3 93.41 0.70 1.49 93.21 85.27
B-8-4 93.03 0.78 1.92 92.73 83.99
B-8-5 96.93 0.70 -0.06 96.85 94.04
B-8-6 96.64 0.77 0.13 96.55 93.21
B-8-7 94.71 0.73 0.63 94.62 88.85
B-8-8 94.31 0.64 0.31 94.27 88.53
B-8-9 96.99 0.24 0.26 96.97 93.71

No.	L	a	b	Whiteness (Lab)	Whiteness (Hunter)
B-8-1	95.61	0.94	0.62	95.47	90.57
B-8-2	93.45	0.74	1.68	93.19	85.08
B-8-3	93.41	0.70	1.49	93.21	85.27
B-8-4	93.03	0.78	1.92	92.73	83.99
B-8-5	96.93	0.70	-0.06	96.85	94.04
B-8-6	96.64	0.77	0.13	96.55	93.21
B-8-7	94.71	0.73	0.63	94.62	88.85
B-8-8	94.31	0.64	0.31	94.27	88.53
B-8-9	96.99	0.24	0.26	96.97	93.71

Mean diameter, amount of particles floating in water and density of micro Shirasu-balloons.

No. Mean
diameter
(µm) Particles
floating
(wt%) Particles floating after
dispersed with ultra-sonic
(wt%) Particle
density
(g/cm³) Bulk
density
(g/cm³) Tapped
bulk density
(g/cm³)
B-1-1 23.0 37.6 19.7 1.11 0.28 0.40
B-1-2 24.2 42.9 29.0 1.02 0.29 0.38
B-1-3 37.8 46.3 28.0 0.80 0.16 0.20
B-2-1 29.0 5.2 1.9 1.90 0.33 0.49
B-3-1 50.0 58.9 24.2 0.81 0.16 0.21
B-3-2 31.0 53.1 27.8 0.94 0.22 0.29
B-4-1 20.3 21.9 12.1 1.28 0.27 0.37
B-4-2 16.1 99.7 99.2 0.66 0.25 0.32
B-5-1 14.0 19.2 9.4 1.37 0.17 0.26
B-5-2 19.3 17.2 5.2 1.48 0.16 0.24
B-5-3 27.7 93.7 63.8 0.81 0.12 0.17
B-5-4 18.6 16.2 4.3 1.44 0.17 0.27
B-6-1 22.4 22.9 14.0 1.31 0.28 0.42
B-7-1 12.2 20.7 13.7 1.21 0.11 0.18
B-7-2 12.4 21.7 12.6 1.16 0.12 0.18

No.	Mean diameter (µm)	Particles floating (wt%)	Particles floating after dispersed with ultra-sonic (wt%)	Particle density (g/cm³)	Bulk density (g/cm³)	Tapped bulk density (g/cm³)
B-1-1	23.0	37.6	19.7	1.11	0.28	0.40
B-1-2	24.2	42.9	29.0	1.02	0.29	0.38
B-1-3	37.8	46.3	28.0	0.80	0.16	0.20
B-2-1	29.0	5.2	1.9	1.90	0.33	0.49
B-3-1	50.0	58.9	24.2	0.81	0.16	0.21
B-3-2	31.0	53.1	27.8	0.94	0.22	0.29
B-4-1	20.3	21.9	12.1	1.28	0.27	0.37
B-4-2	16.1	99.7	99.2	0.66	0.25	0.32
B-5-1	14.0	19.2	9.4	1.37	0.17	0.26
B-5-2	19.3	17.2	5.2	1.48	0.16	0.24
B-5-3	27.7	93.7	63.8	0.81	0.12	0.17
B-5-4	18.6	16.2	4.3	1.44	0.17	0.27
B-6-1	22.4	22.9	14.0	1.31	0.28	0.42
B-7-1	12.2	20.7	13.7	1.21	0.11	0.18
B-7-2	12.4	21.7	12.6	1.16	0.12	0.18

Mean diameter, amount of particles floating in water and density of comparison samples.

No. Mean
diameter
(µm) Particles
floating
(wt%) Particles floating after
dispersed with ultra-sonic
(wt%) Particle
density
(g/cm³) Bulk
density
(g/cm³) Tapped
bulk density
(g/cm³)
B-8-1 _11.9 27.8 26.2 1.16 0.45 0.60
B-8-2 _34.1 86.0 75.7 0.28 0.12 0.15
B-8-3 _32.2 82.1 72.3 0.31 0.16 0.18
B-8-4 _36.6 82.4 76.8 0.34 0.17 0.20
B-8-5 _28.2 84.1 81.2 0.34 0.16 0.19
B-8-6 _36.2 83.1 79.6 0.36 0.16 0.20
B-8-7 _30.2 67.0 62.7 0.50 0.28 0.35
B-8-8 _28.9 70.7 69.8 0.61 0.28 0.36
B-8-9 _28.3 84.5 54.5 0.20 0.08 0.10

No.	Mean diameter (µm)	Particles floating (wt%)	Particles floating after dispersed with ultra-sonic (wt%)	Particle density (g/cm³)	Bulk density (g/cm³)	Tapped bulk density (g/cm³)
B-8-1	_11.9	27.8	26.2	1.16	0.45	0.60
B-8-2	_34.1	86.0	75.7	0.28	0.12	0.15
B-8-3	_32.2	82.1	72.3	0.31	0.16	0.18
B-8-4	_36.6	82.4	76.8	0.34	0.17	0.20
B-8-5	_28.2	84.1	81.2	0.34	0.16	0.19
B-8-6	_36.2	83.1	79.6	0.36	0.16	0.20
B-8-7	_30.2	67.0	62.7	0.50	0.28	0.35
B-8-8	_28.9	70.7	69.8	0.61	0.28	0.36
B-8-9	_28.3	84.5	54.5	0.20	0.08	0.10

Strength (amount of nonfractured particles after compressing) of micro Shirasu-balloons.

No. Particle density
before
testing
(g/cm³) Particle density
after uniaxial
compressing at 5MPa
(g/cm³) Nonfractured particles
after uniaxial
compressing at 5MPa
(wt%) Particle density
after hydrostatics
compressing at 8MPa
(g/cm³) Nonfractured particles
after hydrostatics
compressing at 8MPa
(wt%)
B-1-1 1.11 1.30 72.3 1.24 80.1
B-1-2 1.02 1.29 63.0 1.11 85.7
B-1-3 0.80 2.03 8.1 1.42 33.8
B-2-1 1.90 2.07 57.1 1.92 94.6
B-3-1 0.81 1.37 37.6 1.38 37.0
B-3-2 0.94 1.37 47.7 1.19 65.0
B-4-1 1.28 1.63 52.8 1.41 79.8
B-4-2 0.66 0.81 74.2 0.67 97.9
B-5-1 1.37 1.66 58.1 1.50 79.2
B-5-2 1.48 1.94 36.0 1.77 55.7
B-5-3 0.81 1.67 21.4 1.22 48.7
B-5-4 1.44 1.75 54.3 1.59 75.6
B-6-1 1.31 1.55 65.0 1.34 94.9
B-7-1 1.21 1.63 46.9 1.26 91.8
B-7-2 1.16 1.54 51.3 1.17 98.3

No.	Particle density before testing (g/cm³)	Particle density after uniaxial compressing at 5MPa (g/cm³)	Nonfractured particles after uniaxial compressing at 5MPa (wt%)	Particle density after hydrostatics compressing at 8MPa (g/cm³)	Nonfractured particles after hydrostatics compressing at 8MPa (wt%)
B-1-1	1.11	1.30	72.3	1.24	80.1
B-1-2	1.02	1.29	63.0	1.11	85.7
B-1-3	0.80	2.03	8.1	1.42	33.8
B-2-1	1.90	2.07	57.1	1.92	94.6
B-3-1	0.81	1.37	37.6	1.38	37.0
B-3-2	0.94	1.37	47.7	1.19	65.0
B-4-1	1.28	1.63	52.8	1.41	79.8
B-4-2	0.66	0.81	74.2	0.67	97.9
B-5-1	1.37	1.66	58.1	1.50	79.2
B-5-2	1.48	1.94	36.0	1.77	55.7
B-5-3	0.81	1.67	21.4	1.22	48.7
B-5-4	1.44	1.75	54.3	1.59	75.6
B-6-1	1.31	1.55	65.0	1.34	94.9
B-7-1	1.21	1.63	46.9	1.26	91.8
B-7-2	1.16	1.54	51.3	1.17	98.3

Strength (amount of nonfractured particles after compressing) of comparison samples.

No. Particle density
before
testing
(g/cm³) Particle density
after uniaxial
compressing at 5MPa
(g/cm³) Nonfractured particles
after uniaxial
compressing at 5MPa
(wt%) Particle density
after hydrostatics
compressing at 8MPa
(g/cm³) Nonfractured particles
after hydrostatics
compressing at 8MPa
(wt%)
B-8-1 1.16 1.19 95.0 1.17 98.3
B-8-2 0.28 1.07 16.2 0.44 58.7
B-8-3 0.31 1.14 16.1 0.35 86.8
B-8-4 0.34 0.95 14.9 0.36 93.5
B-8-5 0.34 0.90 27.2 0.35 97.3
B-8-6 0.36 0.79 35.7 0.39 91.5
B-8-7 0.50 0.94 40.8 0.50 99.7
B-8-8 0.61 0.63 96.8 0.61 99.8
B-8-9 0.20 1.20 8.7 0.53 31.5

No.	Particle density before testing (g/cm³)	Particle density after uniaxial compressing at 5MPa (g/cm³)	Nonfractured particles after uniaxial compressing at 5MPa (wt%)	Particle density after hydrostatics compressing at 8MPa (g/cm³)	Nonfractured particles after hydrostatics compressing at 8MPa (wt%)
B-8-1	1.16	1.19	95.0	1.17	98.3
B-8-2	0.28	1.07	16.2	0.44	58.7
B-8-3	0.31	1.14	16.1	0.35	86.8
B-8-4	0.34	0.95	14.9	0.36	93.5
B-8-5	0.34	0.90	27.2	0.35	97.3
B-8-6	0.36	0.79	35.7	0.39	91.5
B-8-7	0.50	0.94	40.8	0.50	99.7
B-8-8	0.61	0.63	96.8	0.61	99.8
B-8-9	0.20	1.20	8.7	0.53	31.5

Heatproof temperature of micro Shirasu-balloons of producing or developing.

No. Temperature at linear shrinkage of 5%
(°C) Temperature at linear shrinkage of 10%
(°C) Predicted refractoriness
(SK)
B-1-1 946 998 8+
B-1-3 1010 1078 12-
B-2-1 980 1054 11+
B-3-2 916 978 9+
B-4-1 1000 1072 11-
B-4-2 1022 1058 12-
B-6-1 972 1028 11
B-7-2 948 1004 9

No.	Temperature at linear shrinkage of 5% (°C)	Temperature at linear shrinkage of 10% (°C)	Predicted refractoriness (SK)
B-1-1	946	998	8+
B-1-3	1010	1078	12-
B-2-1	980	1054	11+
B-3-2	916	978	9+
B-4-1	1000	1072	11-
B-4-2	1022	1058	12-
B-6-1	972	1028	11
B-7-2	948	1004	9

Heatproof temperature of comparison sample from SiO₂-B₂O₃ glass.

No. Temperature at linear shrinkage of 5%
(°C) Temperature at linear shrinkage of 10%
(°C) Predicted refractoriness
(SK)
B-8-1 666 714 -
B-8-2 692 762 -
B-8-4 704 766 -
B-8-5 674 708 -
B-8-6 652 682 -
B-8-7 670 712 -
B-8-8 630 662 -
B-8-9 672 706 -