FOAM BODY, LAYERED FOAM BODY, LAMINATE AND HOUSING BUILDING MATERIAL

Abstract

The present invention provides a foam, a laminated foam, and a laminate that are capable of providing good walking comfort and exhibiting excellent vibration-damping properties while being lightweight and are also useful for recycling interlayer films for a laminated glass. The present invention also aims to provide a building material for housing including any of the foam, the laminated foam, and the laminate. Provided is a foam having a plurality of cells, the foam containing a polyvinyl acetal and a plasticizer and having an average aspect ratio (a/b) of cells of 1.1 or greater as calculated by a predetermined method.

Claims

1. A foam having a plurality of cells, the foam comprising: a polyvinyl acetal; and a plasticizer, the foam having an average aspect ratio (a/b) of cells of 1.1 or greater, the average aspect ratio (a/b) being calculated by a method wherein the foam is bonded to a PET film having a thickness of 100 μm, cut to a size having a width in TD of 4 mm and a length in MD of 17 mm, and imaged with an X-ray CT device to obtain an image of a center portion in a thickness direction having a thickness of 3 mm, a width in TD of 3 mm, and a width in MD of 15 mm; the obtained image is subjected to three-dimensional analysis using image processing software, followed by binarization to separate cell portions from resin portions; subsequently, a cell region touching an image edge is deleted, and three-dimensionally independent cells are labelled; and finally, an aspect ratio, a/b, is calculated where a is a width that each extracted cell region occupies in the thickness direction and b is a width that the cell region occupies in TD.

2. The foam according to claim 1, having a compressive elastic modulus of 2 MPa or less.

3. The foam according to claim 1, further comprising a tackifier.

4. The foam according to claim 3, wherein the tackifier is a hydrogenated petroleum resin having a softening point of 100° C. or higher.

5. The foam according to claim 1, further comprising a filler.

6. The foam according to claim 5, wherein the filler is barium sulfate.

7. The foam according to claim 1, further comprising a thermoplastic elastomer and/or a liquid crystal polymer.

8. A laminated foam comprising: the foam according to claim 1; and a non-woven fabric laminated on at least one main surface of the foam.

9. A laminate comprising: a resin sheet containing a polyvinyl acetal, a plasticizer, and a foaming agent; and a non-woven fabric laminated on at least one main surface of the resin sheet.

10. A building material for housing, the building material comprising: the foam according to claim 1; a laminated foam comprising the foam according to claim 1 and a non-woven fabric laminated on at least one main surface of the foam; or a laminate comprising a resin sheet containing a polyvinyl acetal, a plasticizer, and a foaming agent, and a non-woven fabric laminated on at least one main surface of the resin sheet.

Description

DESCRIPTION OF EMBODIMENTS

[0112] The embodiments of the present invention are more specifically described in the following with reference to, but not limited to, examples.

[0113] The following compounds were used as compounding components for resin compositions in examples and comparative examples.

(1) Polyvinyl acetal

[0114] Polyvinyl butyral 1 (PVB1): hydroxy group content 31 mol %, degree of acetylation 0.7 mol %, degree of butyralization 68.3 mol %, average degree of polymerization 1,800

[0115] Polyvinyl butyral 2 (PVB2): hydroxy group content 22.0 mol %, degree of acetylation 4.0 mol %, degree of butyralization 74.0 mol %, average degree of polymerization 550

(2) Plasticizer: triethylene glycol di-2-ethylhexanoate (3GO)
(3) Tackifier: ARKON M-135, produced by Arakawa Chemical Industries Ltd. (softening point 135° C.)
(4) Thermoplastic elastomer: styrene-ethylene-butylene-styrene copolymer (S1605, produced by Asahi Kasei Corp.)
(5) Liquid crystal polymer: LCP AL-7000, produced by Ueno Fine Chemicals Industry, Ltd.
(6) Filler: barium sulfate (barytes powder FBA, produced by Nippon Talc Co., Ltd.)
(7) Foaming agent: VINYFOR AC#R, produced by Eiwa Chemical Ind. Co., Ltd.

Example 1

(1) Production of Foam

[0116] To 100 parts by weight of polyvinyl butyral 1 (PVB1) were added 40 parts by weight of the plasticizer and 6 parts by weight of the foaming agent, whereby a resin composition was obtained. The obtained resin composition was sufficiently kneaded at 110° C. with a mixing roll and then extruded with an extruder into a sheet. This sheet is also referred to as a resin sheet.

[0117] A non-woven fabric SPC (N) (produced by Nippon Paper Papylia Co., Ltd., type: pulp, mass per unit area: 15 g/m.sup.2) was placed on both surfaces of the resin sheet and thermally compression-bonded at 120° C. with a press machine, whereby a laminate was obtained. The obtained laminate was placed in an oven without being cooled, and the heat-decomposable foaming agent was decomposed at 210° C. for five minutes in the oven, whereby a sheet-shaped foam was obtained.

(2) Calculation of Average Aspect Ratio of Cells

[0118] The average aspect ratio (a/b) of cells was determined in conformity with the method described above. Specifically, the aspect ratio was determined as follows.

[0119] The foam sheet was bonded to a PET film having a thickness of 100 μm, cut to a size having a width in TD of 4 mm and a length in MD 17 mm, and subjected to three-dimensional measurement with an X-ray CT device for a center portion in the thickness direction having a thickness of 3 mm, a width in TD of 3 mm, and a width in MD of 15 mm.

[0120] The X-ray CT device is not limited. In this experiment, nano3DX produced by Rigaku Corporation was used. The X-ray source was Mo. The resolution was 2.16 μm/pixel (lens 1080, binning 2). The exposure time was 20 seconds/image, and 1,000 images were obtained.

[0121] The obtained images were subjected to three-dimensional image analysis using image processing software “Avizo 2019.4” (produced by ThermoFisher Scientific).

[0122] Using the Auto Thresholding module, binarization was performed at the following settings to separate cell portions from resin portions.

Type: Auto Thresholding High

Interpretation: 3D

[0123] Mode: min-max
Criterion: factorisation

[0124] Next, cell regions touching the image edges were deleted using the Border Kill module, and three-dimensionally independent cells were labelled using the Labeling module.

[0125] Finally, the aspect ratio (a/b) was determined, where a is the width each extracted cell region occupies in the thickness direction and b is the width the cell region occupies in TD.

(3) Calculation of Expansion Ratio

[0126] The apparent density of the obtained foam was measured in conformity with JIS K7222 (2005). The density of the resin sheet before foaming was divided by the density (apparent density) of the foam after foaming to calculate the expansion ratio.

(4) Measurement of Thickness

[0127] The thickness of the obtained foam was measured.

(5) Measurement of Compressive Elastic Modulus

[0128] Using a specimen (300 mm×300 mm) cut out from the obtained foam, the compressive elastic modulus was measured in conformity with JIS K7181 (2011) when the specimen was compressed at a test rate of 10 ram/min with an indenter having a diameter of 50 mm.

Example 2

[0129] A resin sheet was obtained as in Example 1 except that the filler was added in the amount shown in Table 1. A sheet-shaped foam was then obtained as in Example 1 except that ECULE 3151A (produced by Toyobo Co., Ltd., type: polyester (PEs), mass per unit area: 15 g/m.sup.2) was used as the non-woven fabric. The foam was subjected to the evaluation of physical properties and the like.

Example 3

[0130] A resin sheet was obtained as in Example 1 except that the filler and the tackifier were added in the respective amounts shown in Table 1. A sheet-shaped foam was then obtained as in Example 2 and subjected to the evaluation of physical properties and the like.

Example 4

[0131] A resin sheet was obtained as in Example 1 except that the filler and the thermoplastic elastomer were added in the respective amounts shown in Table 1. A sheet-shaped foam was then obtained as in Example 2 and subjected to the evaluation of physical properties and the like.

Example 5

[0132] A resin sheet was obtained as in Example 1 except that the filler and the liquid crystal polymer were added in the respective amounts shown in Table 1. A sheet-shaped foam was then obtained as in Example 2 and subjected to the evaluation of physical properties and the like.

Example 6

[0133] A resin sheet was obtained as in Example 1 except that PVB2 was used instead of PVB1, and that the tackifier, the thermoplastic elastomer, and the filler were added in the respective amounts shown in Table 1. A sheet-shaped foam was then obtained as in Example 1 except that ECULE 3301A (produced by Toyobo Co., Ltd., type: PEs, mass per unit area: 30 g/m.sup.2) was used as a non-woven fabric. The foam was subjected to the evaluation of physical properties and the like.

Example 7

[0134] A resin sheet was obtained as in Example 1 except that PVB2 was used instead of PVB1, that the amount of the plasticizer was changed to the amount shown in Table 1, and that the filler was added in the amount shown in Table 1. A sheet-shaped foam was then obtained as in Example 1 except that ECULE 3351A (produced by Toyobo Co., Ltd., type: PEs, mass per unit area: 15 g/m.sup.2) was used as the non-woven fabric and that the sheet-shaped foam was cut to a thickness of 6 mm with Bandknife splitting machine, Slicer (produced by Nippi, Inc.). The foam was subjected to the evaluation of physical properties and the like.

Comparative Example 1

[0135] A sheet-shaped foam was obtained as in Example 1 except that Milife T05 (produced by ENEOS Techno Materials Corporation, type: PEs, mass per unit area: 5 g/m.sup.2) was used as the non-woven fabric. The foam was subjected to the evaluation of physical properties and the like.

Comparative Example 2

[0136] The resin sheet obtained in Example 1 was placed in an oven to decompose the heat-decomposable foaming agent at a foaming temperature of 210° C. for five minutes, whereby a sheet-shaped foam was prepared. The foam was subjected to the evaluation of physical properties and the like as in Example 1.

Comparative Example 3

[0137] A commercial polyethylene foam (produced by Sekisui Chemical Co., Ltd., Softlon S, expansion ratio 10 times) was provided as a comparative example. This polyethylene foam was subjected to the evaluation of physical properties and the like as in Example 1.

(Evaluation)

[0138] The foams obtained in the examples and the comparative examples were evaluated by the following methods. Table 1 shows the results.

(1) Evaluation of Walking Comfort

[0139] The foam and a floor finishing material were stacked in this order on a flooring base. A tester walked on the floor finishing material. The feel during the walk was expressed as a score by sensory evaluation in accordance with the following criteria. The walking comfort was evaluated as “A” when this score was 2, 3, or 4. The walking comfort was evaluated as “B” when the score was 1 or 5.

5: Hard

[0140] 4: Slightly hard

3: Intermediate

[0141] 2: Slightly soft

1: Soft

(2) Vibration-Damping Properties

[0142] The loss factor and the anti-resonance frequencies at ° C. were measured by mechanical impedance measurement (MIM) in conformity with JIS K7391 (2008).

[0143] Specifically, the foam was fixed between a steel plate having a width of 12 mm, a length of 240 mm, and a thickness of 1.2 mm and an aluminum plate (0.3 mm) having the same size using a double-sided tape (produced by Sekisui Chemical Co., Ltd., #5782). The resulting laminate sample was used to measure the loss factor and the anti-resonance frequencies by the central exciting method. The vibration-damping properties were evaluated in accordance with the following criteria. The table shows the second anti-resonance point and the loss factor.

(Rating)

[0144] A: The loss factor was 0.1 or greater at an anti-resonance point at 800 Hz or less.
B: The loss factor was less than 0.1 at an anti-resonance point at 800 Hz or less.

TABLE-US-00001 TABLE 1 Com- Com- Com- para- para- para- tive tive tive Ex- Ex- Ex- Ex- Ex- Ex- Ex- Ex- Ex- Ex- ample ample ample ample ample ample ample ample ample ample 1 2 3 4 5 6 7 1 2 3 Foam Compo- Polyvinyl acetal PVB1 100 100 100 100 100 — — 100 100 sition PVB2 — — — — — 100 100 — — (parts by Plasticizer 40 40 40 40 40 40 20 40 40 weight) Polyethylene — — — — — — — — — 100 Tackifier — — 15 — — 5 — — — — Thermoplastic elastomer — — — 15 — 10 — — — — Liquid crystal polymer — — — — 15 — — — — — Filler — 50 50 50 30 40 30 — — — Physical Aspect ratio (a/b) 1.2 2.2 4.6 1.8 3.2 1.1 2.7 0.9 0.8 1.2 properties Foaming ratio [times] 2.1 3.6 5.8 2.9 4.2 1.5 3.9 2.1 2.5 10 Thickness [mm] 5 5 5 5 5 5 5 5 5 5 Compressive elastic 1.1 1.2 1.0 1.5 1.4 1.5 1.8 0.9 0.8 3.5 modulus [MPa] Structure Non-woven fabric (type/ Pulp/ PEs/ PEs/ PEs/ PEs/ PEs/ PEs/ PEs/ — — mass per unit area [g/m.sup.2]) 15 15 15 15 15 30 15 5 Slice Not Not Not Not Not Not Sliced Not — — sliced sliced sliced sliced sliced sliced sliced Evaluation Walking comfort A/2 A/3 A/2 A/4 A/4 A/4 A/4 B/1 B/1 A/2 (rating/score) Second anti- Hz 583 598 602 592 618 627 624 588 573 543 resonance point Loss factor 0.16 0.22 0.25 0.24 0.2 0.18 0.18 0.13 0.13 0.06 Vibration-damping A A A A A A A A A B properties (rating)

INDUSTRIAL APPLICABILITY

[0145] The present invention can provide a foam, a laminated foam, a laminate, and a building material for housing that are capable of providing good walking comfort and exhibiting excellent vibration-damping properties while being light weight and are also useful for recycling interlayer films for a laminated glass.