Resin foam, resin foam sheet, adhesive tape, vehicle member, and building member

Abstract

The present invention aims to provide a resin foam, a resin foam sheet, an adhesive tape, a member for a vehicle, and a member for a building that are capable of exhibiting very high sound insulation properties. Provided is a resin foam having a multitude of cells, the resin foam containing: a thermoplastic resin; and a plasticizer, the resin foam having a minimum loss factor of a primary anti-resonance frequency in the range of 20° C. to 60° C. of 0.05 or higher and a secondary anti-resonance frequency in the range of 20° C. to 60° C. of 300 to 800 Hz as measured by mechanical impedance measurement (MIM) in conformity with JIS G0602.

Claims

1. A resin foam having a multitude of cells, the resin foam comprising: a thermoplastic resin; and a plasticizer, the resin foam having an open cell ratio of 20% or higher, the resin foam having a minimum loss factor of a primary anti-resonance frequency in the range of 20° C. to 60° C. of 0.05 or higher and a secondary anti-resonance frequency in the range of 20° C. to 60° C. of 300 to 800 Hz as measured by mechanical impedance measurement (MIM) in conformity with JIS G0602.

2. A resin foam having a multitude of cells, the resin foam comprising: a thermoplastic resin; and a plasticizer, the resin foam having an open cell ratio of 20% or higher, the resin foam having a minimum loss factor of a primary anti-resonance frequency in the range of 20° C. to 60° C. of 0.005 or higher and a secondary anti-resonance frequency in the range of 20° C. to 60° C. of 300 to 800 Hz as measured by mechanical impedance measurement (MIM) in conformity with JIS K7391.

3. A resin foam having a multitude of cells, the resin foam comprising: a thermoplastic resin; and a plasticizer, the resin foam having an open cell ratio of 20% or higher, the resin foam having a maximum loss factor of a primary anti-resonance frequency in the range of 0° C. to 50° C. of 0.20 or higher and a secondary anti-resonance frequency in the range of 0° C. to 30° C. of 800 Hz or lower as measured by mechanical impedance measurement (MIM) in conformity with ISO 16940.

4. The resin foam according to claim 3, wherein the maximum loss factor of the primary anti-resonance frequency in the range of 0° C. to 50° C. is 0.24 or higher as measured by mechanical impedance measurement (MIM) in conformity with ISO 16940.

5. The resin foam according to claim 1, further comprising an adhesive.

6. A resin foam sheet comprising: the resin foam according to claim 1.

7. An adhesive tape comprising: the resin foam sheet according to claim 6; and an adhesive layer provided on at least one surface of the resin foam sheet.

8. A member for a vehicle, comprising: the resin foam according to claim 1.

9. A member for a building, comprising: the resin foam according to claim 1.

10. The resin foam according to claim 2, further comprising an adhesive.

11. The resin foam according to claim 3, further comprising an adhesive.

12. A resin foam sheet comprising: the resin foam according to claim 2.

13. A resin foam sheet comprising: the resin foam according to claim 3.

14. An adhesive tape comprising: the resin foam sheet according to claim 12; and an adhesive layer provided on at least one surface of the resin foam sheet.

15. An adhesive tape comprising: the resin foam sheet according to claim 13; and an adhesive layer provided on at least one surface of the resin foam sheet.

16. A member for a vehicle, comprising: the resin foam according to claim 2.

17. A member for a vehicle, comprising: the resin foam according to claim 3.

18. A member for a building, comprising: the resin foam according to claim 2.

19. A member for a building, comprising: the resin foam according to claim 3.

20. The resin foam according to claim 1, wherein an amount of the plasticizer in the resin foam is 20 to 60 parts by weight relative to 100 parts by weight of the thermoplastic resin.

21. The resin foam according to claim 2, wherein an amount of the plasticizer in the resin foam is 20 to 60 parts by weight relative to 100 parts by weight of the thermoplastic resin.

22. The resin foam according to claim 3, wherein an amount of the plasticizer in the resin foam is 20 to 60 parts by weight relative to 100 parts by weight of the thermoplastic resin.

23. The resin foam according to claim 1, wherein the plasticizer includes triethylene glycol di-2-ethylhexanoate.

24. The resin foam according to claim 2, wherein the plasticizer includes triethylene glycol di-2-ethylhexanoate.

25. The resin foam according to claim 3, wherein the plasticizer includes triethylene glycol di-2-ethylhexanoate.

Description

DESCRIPTION OF EMBODIMENTS

(1) Embodiments of the present invention are more specifically described in the following with reference to, but not limited to, examples.

Example 1

(2) (1) Production of Resin Foam

(3) To 100 parts by weight of polyvinyl butyral 1 (PVB1) were added 40 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) as plasticizer and 9 parts by weight of CELLMIC CE (available from Sankyo Kasei Co., Ltd., decomposition temperature: 208° C.) as a heat-decomposable foaming agent to give a resin composition. The obtained resin composition was sufficiently kneaded at 110° C. with a mixing roll and then extruded from an extruder into a sheet. PVB1 had a hydroxy group content of 34 mol %, a degree of acetylation of 1.0 mol %, a degree of butyralization of 65 mol %, and an average degree of polymerization of 1,650.

(4) The obtained sheet was placed in an oven to decompose the heat-decomposable foaming agent at a foaming temperature of 220° C., whereby a resin foam in a sheet form (resin foam sheet) was obtained. The obtained resin foam sheet had a thickness of 4 mm.

(5) (2) Measurement of Open Cell Ratio and Apparent Density

(6) The open cell ratio of the obtained resin foam was measured by pycnometry in conformity with JIS K 7138. The apparent density was obtained by calculation based on the measured weight and the apparent volume obtained from size measurement.

(7) (3) Measurement of Loss Factor of Primary Anti-Resonance Frequency and Secondary Anti-Resonance Frequency

(8) (3-1) Measurement in Conformity with JIS G0602

(9) Mechanical impedance measurement (MIM) was conducted in conformity with JIS G0602 to measure the loss factor of the primary anti-resonance frequency in the range of 20° C. to 60° C. and the secondary anti-resonance frequency in the range of 20° C. to 60° C.

(10) Specifically, the loss factor of the primary anti-resonance frequency and the secondary anti-resonance frequency were measured by a central exciting method using a laminate sample. The sample was prepared by fixing the resin foam between two steel plates that were each 12 mm wide, 240 mm long, and 1.6 mm thick with a double-sided adhesive tape (available from Sekisui Chemical Co., Ltd., #5782).

(11) (3-2) Measurement in Conformity with JIS K7391

(12) Mechanical impedance measurement (MIM) was conducted in conformity with JIS K7391 to measure the loss factor of the primary anti-resonance frequency in the range of 20° C. to 60° C. and the secondary anti-resonance frequency in the range of 20° C. to 60° C.

(13) Specifically, the loss factor of the primary anti-resonance frequency and the secondary anti-resonance frequency were measured by a central exciting method using a laminate sample. The sample was prepared by fixing the resin foam to a steel plate that was 12 mm wide, 240 mm long, and 1.6 mm thick with a double-sided adhesive tape (available from Sekisui Chemical Co., Ltd., #5782).

(14) (3-3) Measurement in Conformity with ISO 16940

(15) Mechanical impedance measurement (MIM) was conducted in conformity with ISO 16940 to measure the loss factor of the primary anti-resonance frequency in the range of 0° C. to 50° C. and the secondary anti-resonance frequency in the range of 0° C. to 30° C.

(16) Specifically, the loss factor of the primary anti-resonance frequency and the secondary anti-resonance frequency were measured by a central exciting method using a laminate sample. The sample was prepared by fixing the resin foam between two glass plates that were each 25 mm wide, 305 mm long, and 2 mm thick with a double-sided adhesive tape (available from Sekisui Chemical Co., Ltd., #5782).

Examples 2 to 4 and Comparative Example 4

(17) A resin foam was produced and the loss factor of the primary anti-resonance frequency and the secondary anti-resonance frequency were measured as in Example 1 except that the amounts of the heat-decomposable foaming agent and the plasticizer were as shown in Table 1.

Example 5

(18) A resin foam was produced and the loss factor of the primary anti-resonance frequency and the secondary anti-resonance frequency were measured as in Example 1 except that polyvinyl butyral 2 (PVB2) was used instead of polyvinyl butyral 1, and that the amount of the heat-decomposable foaming agent was as shown in Table 1. PVB2 had a hydroxy group content of 23 mol %, a degree of acetylation of 13 mol %, a degree of butyralization of 64 mol %, and an average degree of polymerization of 2,400.

Comparative Example 1

(19) A commercially available polyethylene foam (available from Sekisui Chemical Co., Ltd., Softlon S, expansion ratio: 30 times) was provided as a comparative example. The loss factor of the primary anti-resonance frequency and the secondary anti-resonance frequency of the polyethylene foam were measured as in Example 1.

Comparative Example 2

(20) A commercially available ethylene-vinyl acetate copolymer (EVA) foam (available from Mitsufuku Industry Co., Ltd., MITSUFUKU FOAM V10) was provided as a comparative example. The loss factor of the primary anti-resonance frequency and the secondary anti-resonance frequency of the EVA foam were measured as in Example 1.

Comparative Example 3

(21) A commercially available urethane gel (available from Exseal Co., Ltd., EXSEAL) was provided as a comparative example. The loss factor of the primary anti-resonance frequency and the secondary anti-resonance frequency of the urethane gel were measured as in Example 1.

Comparative Example 5

(22) A resin foam was produced and the loss factor of the primary anti-resonance frequency and the secondary anti-resonance frequency were measured as in Example 1 except that CELLMIC CAP (available from Sankyo Kasei Co., Ltd., decomposition temperature: 125° C.) was used as a heat-decomposable foaming agent, and that the foaming temperature was 150° C.

(23) (Evaluation)

(24) The resin foams obtained in the examples and comparative examples were evaluated as follows.

(25) Tables 1 and 2 show the results.

(26) (Evaluation 1 of Sound Insulation Properties)

(27) The sound transmission loss was measured by a sound intensity method in conformity with JIS A 1441. The measurement was performed at a measurement temperature of 20° C. for each ⅓ octave band in the frequency range of 100 to 10,000 Hz. The sample was prepared by interposing a resin foam sample (thickness: about 4 mm) between 2-mm-thick glass plates and fixing the resin foam sample with a double-sided adhesive tape (available from Sekisui Chemical Co., Ltd., #5782). The size (the opening) was 500 mm×500 mm. The incident power was calculated from the average sound pressure level of 5 points in the reverberation room. The transmitted power was calculated from the sound intensity at 5×5=25 points in the measurement area (500 mm×500 mm).

(28) The sound insulation properties were evaluated in accordance with the following criteria.

(29) A frequency-transmission loss graph was plotted. The sound insulation properties were evaluated as “0 (Good)” when the difference in transmission loss between the first local maximum on the low frequency side and its adjacent local minimum is 7 dB or less, and evaluated as “x (Poor)” when the difference in transmission loss was more than 7 dB.

(30) (Evaluation 2 of Sound Insulation Properties)

(31) The airborne sound insulation properties were evaluated in conformity with JIS A 1417-1, Rating of sound insulation in buildings and building elements: Airborne sound insulation.

(32) The measurement was performed at a measurement temperature of 25° C. for each 1/1 octave band in the frequency range of 31.5 to 4,000 Hz. The sample was prepared by fixing a resin foam sample (thickness: about 4 mm) to a plaster board with a double-sided adhesive tape (available from Sekisui Chemical Co., Ltd., #5782). The size (the opening) was 990 mm×990 mm. A sound was produced from the reverberation room side at a sound pressure of 100 dB, and the differential pressure was measured on the anechoic room side.

(33) The sound insulation properties were evaluated in accordance with the following criteria.

(34) A 1/1 octave band frequency-sound pressure level graph was plotted. The sound insulation properties were evaluated as “o (Good)” when the average DM value was +1.0 dB or more relative to the value without the resin foam, and evaluated as “x (Poor)” when the average DM value was less than +1.0 dB relative to the value without the resin foam.

(35) (Evaluation 3 of Sound Insulation Properties)

(36) The airborne sound insulation properties were evaluated in conformity with JIS A 1417-1, Rating of sound insulation in buildings and building elements: Airborne sound insulation.

(37) The measurement was performed at a measurement temperature of 25° C. for each 1/1 octave band in the frequency range of 31.5 to 4,000 Hz. The sample was prepared by fixing aluminum (0.3 mm) to the resin foam (thickness: about 4 mm) with a double-sided adhesive tape (available from Sekisui Chemical Co., Ltd., #5782) and fixing the surface without the aluminum laminated thereon to a plaster board with a double-sided adhesive tape (available from Sekisui Chemical Co., Ltd., #5782). The size (the opening) was 990 mm×990 mm. A sound was produced from the reverberation room side at a sound pressure of 100 dB, and the differential pressure was measured on the anechoic room side.

(38) The sound insulation properties were evaluated in accordance with the following criteria.

(39) A 1/1 octave band frequency-sound pressure level graph was plotted. The sound insulation properties were evaluated as “0 (Good)” when the average DM value was +2.0 dB or more relative to the value without the resin foam, and evaluated as “x (Poor)” when the average DM value was less than +2.0 dB relative to the value without the resin foam.

(40) TABLE-US-00001 TABLE 1 Example 1 Example 2 Example 3 Example 4 Example 5 Resin Thermoplastic resin Type — PVB1 PVB1 PVB1 PVB1 PVB2 composition Amount Parts by weight 100 100 100 100 100 Plasticizer Type — 3GO 3GO 3GO 3GO 3GO Amount Parts by weight 40 40 40 20 60 Foaming agent Type — CELLMIC CELLMIC CELLMIC CELLMIC CELLMIC CE CE CE CE CE Amount Parts by weight 9 4 17 9 8 Foaming temperature ° C. 220 220 220 220 220 Foam Open cell ratio % 86 54 85 63 90 Apparent density kg/m.sup.3 100 130 70 120 90 JIS Loss factor of primary anti- — 0.23 0.22 0.32 0.20 0.35 G0602 resonance peak (maximum value in the range of 20° C. to 60° C.) Loss factor of primary anti- — 0.06 0.06 0.11 0.06 0.13 resonance peak (minimum value in the range of 20° C. to 60° C.) Anti-resonance frequency of Hz 580 630 580 720 580 secondary anti-resonance peak (maximum value in the range of 20° C. to 60° C.) Anti-resonance frequency of Hz 330 400 320 430 320 secondary anti-resonance peak (minimum value in the range of 20° C. to 60° C.) JIS Loss factor of primary anti- — 0.018 0.018 0.025 0.009 0.031 K7391 resonance peak (maximum value in the range of 20° C. to 60° C.) Loss factor of primary anti- — 0.006 0.006 0.007 0.006 0.011 resonance peak (minimum value in the range of 20° C. to 60° C.) Anti-resonance frequency of Hz 690 720 680 740 620 secondary anti-resonance peak (maximum value in the range of 20° C. to 60° C.) Anti-resonance frequency of Hz 540 540 490 440 470 secondary anti-resonance peak (minimum value in the range of 20° C. to 60° C.) ISO Loss factor of primary anti- — 0.38 0.33 0.40 0.24 0.40 16940 resonance peak (maximum value in the range of 0° C. to 50° C.) Loss factor of primary anti- — 0.19 0.16 0.21 0.16 0.20 resonance peak (minimum value in the range of 0° C. to 50° C.) Anti-resonance frequency of Hz 780 500 550 490 560 secondary anti-resonance peak (maximum value in the range of 0° C. to 30° C.) Anti-resonance frequency of Hz 520 350 340 320 300 secondary anti-resonance peak (minimum value in the range of 0° C. to 30° C.) Evaluation Evaluation 1 of sound insulation properties ∘ ∘ ∘ ∘ ∘ Evaluation 2 of sound insulation properties ∘ ∘ ∘ ∘ ∘ Evaluation 3 of sound insulation properties ∘ ∘ ∘ ∘ ∘

(41) TABLE-US-00002 TABLE 2 Comparative Comparative Comparative Comparative Comparative Example 1 Example 2 Example 3 Example 4 Example 5 Resin Thermoplastic resin Type — Polyethylene EVA Urethane gel PVB1 PVB1 composition Amount Parts by weight foam foam 100 100 Plasticizer Type — 3GO 3GO Amount Parts by weight 40 40 Foaming agent Type — CELLMIC CELLMIC CE CAP Amount Parts by weight 2 9 Foaming temperature ° C. — — — 220 150 Foam Open cell ratio % <5 <5 — <5 <5 Apparent density kg/m.sup.3 25 110 1000 950 950 JIS Loss factor of primary anti- — 0.07 0.08 0.05 0.05 0.06 G0602 resonance peak (maximum value in the range of 20° C. to 60° C.) Loss factor of primary anti- — 0.03 0.04 0.03 0.03 0.04 resonance peak (minimum value In the range of 20° C. to 60° C.) Anti-resonance frequency of Hz 570 560 510 560 570 secondary anti-resonance peak (maximum value in the range of 20° C. to 60° C.) Anti-resonance frequency of Hz 480 520 440 320 320 secondary anti-resonance peak (minimum value in the range of 20° C. to 60° C.) JIS Loss factor of primary anti- — 0.007 0.007 0.004 0.007 0.009 K7391 resonance peak (maximum value in the range of 20° C. to 60° C.) Loss factor of primary anti- — 0.002 0.002 0.002 0.003 0.003 resonance peak (minimum value in the range of 20° C. to 60° C.) Anti-resonance frequency of Hz 560 570 480 690 680 secondary anti-resonance peak (maximum value in the range of 20° C. to 60° C.) Anti-resonance frequency of Hz 540 560 460 450 450 secondary anti-resonance peak (minimum value in the range of 20° C. to 60° C.) ISO Loss factor of primary anti- — 0.12 0.16 0.18 0.10 0.10 16940 resonance peak (maximum value in the range of 0° C. to 50° C.) Loss factor of primary anti- — 0.09 0.10 0.05 0.06 0.06 resonance peak (minimum value in the range of 0° C. to 50° C.) Anti-resonance frequency of Hz 580 580 410 1140 1140 secondary anti-resonance peak (maximum value in the range of 0° C. to 30° C.) Anti-resonance frequency of Hz 490 500 400 520 540 secondary anti-resonance peak (minimum value in the range of 0° C. to 30° C.) Evaluation Evaluation 1 of sound insulation properties x x x x x Evaluation 2 of sound insulation properties x x x x x Evaluation 3 of sound insulation properties x x x x x

Example 6

(42) A double-sided adhesive tape for fixing an interior member (available from Sekisui Chemical Co., Ltd., #5782) as an adhesive layer was attached to one surface of the resin foam sheet obtained in Example 1 to give a one-sided adhesive tape.

(43) The obtained one-sided adhesive tape exhibited adhesiveness while maintaining the flexibility and sound insulation properties of the resin foam sheet of Example 1.

(44) In the measurements of the sound insulation properties, the surface of the obtained one-sided adhesive tape to which the double-sided adhesive tape for fixing an interior member (available from Sekisui Chemical Co., Ltd., #5782) was attached was used as it was, with no double-sided adhesive tape newly attached thereto. For the measurements, the double-sided adhesive tape (available from Sekisui Chemical Co., Ltd., #5782) was newly attached only to the surface to which the double-sided adhesive tape for fixing an interior member was not attached.

Example 7

(45) (1) Production of Acrylic Polymer

(46) Into a reaction container were introduced 100 parts by weight of n-butyl acrylate and 11 parts by weight of acrylic acid to give a monomer component. The monomer component was dissolved in ethyl acetate, to which 0.1 parts by weight of lauroyl peroxide as a polymerization initiator was added at the reflux point. The solution was refluxed at 70° C. for five hours to give a solution of an acrylic polymer having a weight average molecular weight of 720,000.

(47) (2) Production of Adhesive Composition and Adhesive Tape

(48) To the obtained acrylic polymer solution were added 6.3 parts by weight of a polymerized rosin ester-type tackifier resin (softening point: 140° C.) containing 13% a component having a molecular weight of 600 or less and 0.054 parts by weight of an aluminum chelate, which is a metal chelate cross-linking agent, as a cross-linking agent, relative to 100 parts by weight of the acrylic polymer (i.e., the non-volatile component of the acrylic polymer solution). They were then uniformly mixed to give an adhesive composition.

(49) Subsequently, the obtained adhesive composition was applied to one surface of the resin foam sheet obtained in Example 1. The adhesive composition was then dried at 120° C. for five minutes to form a one-sided adhesive tape in which an adhesive layer having a thickness of 60 μm was laminated on one surface of the resin foam sheet.

(50) The obtained one-sided adhesive tape exhibited adhesiveness while maintaining the flexibility and sound insulation properties of the resin foam sheet of Example 1. The one-sided adhesive tape did not show a decrease in adhesiveness even one month after adherence.

(51) In the measurements of the sound insulation properties, the surface of the obtained one-sided adhesive tape on which the adhesive layer was laminated was used as it was, with no double-sided adhesive tape newly attached thereto. For the measurements, the double-sided adhesive tape (available from Sekisui Chemical Co., Ltd., #5782) was newly attached only to the surface on which the adhesive layer was not laminated.

(52) (Evaluation)

(53) The one-sided adhesive tapes obtained in Examples 6 and 7 were evaluated as follows.

(54) (Plasticizer Resistance Evaluation)

(55) (1) Sample Preparation

(56) Each of the one-sided adhesive tapes obtained in Examples 6 and 7 was cut to a size of 25 mm in width×150 mm in length, and pressure-bonded to SUS304 (BA surface finish) specified in JIS G4305 by reciprocating a 2-kg rubber roller once at 10 mm/sec in conformity with JIS Z0237.

(57) (2) Measurement of Initial Adhesive Force

(58) The one-sided adhesive tape obtained in the sample preparation was left to stand at 23° C. and 50% RH for 20 minutes after the pressure bonding. The 90° peel test was then performed three times in conformity with JIS 20237. The average value was taken as the initial adhesive force (N/25 mm). The peeling speed was 300 ram/min.

(59) (3) Measurement of Aged Adhesive Force

(60) The sample prepared in the sample preparation was left to stand in an atmosphere at 60° C. for 72 hours, then at 23° C. and 50% RH for 30 minutes. The 90° peel test was then performed three times in conformity with JIS 20237. The average value was taken as the aged adhesive force (N/25 mm).

(61) (4) Evaluation of Adhesive Force Retention

(62) The adhesive force retention (%) was calculated by the following formula based on the initial adhesive force and aged adhesive force obtained above.
Adhesive force retention (%)=100×(Aged adhesive force/Initial adhesive force)

(63) The evaluation results show that the adhesive force retention of the one-sided adhesive tape obtained in Example 7 was greatly improved as compared with that of the one-sided adhesive tape obtained in Example 6.

INDUSTRIAL APPLICABILITY

(64) The present invention can provide a resin foam, a resin foam sheet, an adhesive tape, a member for a vehicle, and a member for a building that are capable of exhibiting very high sound insulation properties.