JP2017222120A - Manufacturing method of high void laminated board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a high void laminated board capable of retaining a relatively large void even when compressed in the thickness direction. SOLUTION: A flat polyester non-woven fabric 21 having a cross-sectional shape composed of polyester long fibers having a shape in which the lower end of a substantially Y shape is connected vertically and horizontally (hereinafter referred to as "substantially Y4 shape") is manufactured. A pair of polka dot rolls in which hemispherical convex portions and concave portions are alternately arranged on the peripheral surface, and the convex portions and concave portions of each polka dot roll are engaged and rotated between the pair of polka dot rolls, and flat polyester. A method for manufacturing a high-void laminated board, in which a polyester non-woven fabric 22 having an uneven pattern is produced by introducing the non-woven fabric 21, flat polyester non-woven fabric 21 is laminated on both sides of the uneven polyester non-woven fabric 22, and the layers are bonded with an adhesive. .. [Selection diagram] Fig. 5

Description

  TECHNICAL FIELD The present invention relates to a method for manufacturing a laminated board having a bulky and relatively large gap, and more particularly to a method for manufacturing a high gap laminated board that can be used as a sound absorbing material, a filter material or the like.

  Conventionally, various types of sound-absorbing materials have been known, but as a bulky material, a material obtained by laminating a nonwoven fabric on both surfaces of a foam is known (Patent Document 1). Such a sound-absorbing material exhibits a sound-absorbing effect by attenuating sound by a relatively small gap formed between constituent fibers of the nonwoven fabric and a relatively large gap of the foam.

形状（以下、「略Ｙ４形状」という。）であることを特徴とするポリエステル不織布というものである。かかるポリエステル不織布は、高剛性であるという特性を持っている。 By the way, this inventor developed the polyester nonwoven fabric with a special cross-sectional shape (patent document 2). This is a non-woven fabric comprising polyester long fibers as a constituent fiber, and the cross-sectional shape of the polyester long fibers is connected to the top, bottom, left and right at the lower end of a substantially Y-shape.

It is a polyester nonwoven fabric characterized by having a shape (hereinafter referred to as “substantially Y4 shape”). Such a polyester nonwoven fabric has a characteristic of high rigidity.

JP 2007-133268 A JP2013-76182A

  The present inventor has conducted various studies using the polyester nonwoven fabric, and the laminated board formed by laminating the polyester nonwoven fabric with a specific concavo-convex pattern on both sides is the thickness direction. It has been found that even when compressed to, a concavo-convex pattern pattern is not easily lost, a relatively large void is maintained, and a laminated boat excellent in sound absorption can be obtained. The present invention is based on such knowledge. Accordingly, an object of the present invention is to obtain a high-gap laminated board that can retain a relatively large gap even when compressed in the thickness direction.

形状（以下、「略Ｙ４形状」という。）のポリエステル長繊維で構成されてなる平坦なポリエステル不織布（以下、「平坦ポリエステル不織布」という。）を製造する工程と、周面に半球状の凸部と凹部が交互に並んでいる一対の水玉ロールであって、各水玉ロールの凸部と凹部は噛合して回転している一対の水玉ロール間に、平坦ポリエステル不織布を導入して、凹凸柄模様を持つポリエステル不織布（以下、「凹凸ポリエステル不織布」という。）を製造する工程と、前記凹凸柄模様を持つポリエステル不織布の両面に、前記平坦なポリエステル不織布を積層し、積層間を接着剤で接着させる工程とを具備することを特徴とする高空隙積層ボードの製造方法に関するものである。 In the present invention, the cross-sectional shape is connected to the top, bottom, left and right at the lower end of a substantially Y shape.

A step of manufacturing a flat polyester nonwoven fabric (hereinafter referred to as “flat polyester nonwoven fabric”) composed of long polyester fibers having a shape (hereinafter referred to as “substantially Y4 shape”), and a hemispherical convex portion on the peripheral surface And a pair of polka dots rolls in which concave portions are arranged alternately, and a convex polyester and a concave portion are formed by introducing a flat polyester nonwoven fabric between a pair of polka dot rolls that mesh and rotate the convex portions and concave portions of each polka dot roll. The polyester non-woven fabric (hereinafter referred to as "uneven polyester non-woven fabric") is manufactured, and the flat polyester non-woven fabric is laminated on both sides of the polyester non-woven fabric having the concavo-convex pattern, and the laminate is adhered with an adhesive. The present invention relates to a method for manufacturing a high-gap laminated board comprising the steps of:

  First, the polyester continuous fiber used by this invention is demonstrated. This polyester continuous fiber is characterized by its cross-sectional shape. This cross-sectional shape has four substantially Y-characters as shown in FIG. And it is connected to the upper and lower sides and the right and left at the lower end 1 of a substantially Y shape, and has a substantially Y4 shape as shown in FIG. The substantially Y4 shape has four concave portions 2, eight convex portions 3, and four small concave portions 4. Thus, the flat polyester nonwoven fabric in which the polyester continuous fibers having a large number of concave portions 2, a large number of small concave portions 4 and a large number of convex portions 3 are integrated has large and small voids formed between the constituent fibers, and the frequency It is easy to attenuate various different sounds and is suitable as a material for a sound absorbing material. Moreover, since dust is easily trapped at the four recesses 2 and is excellent in dust removal, it is also suitable as a material for the filter material. Further, high rigidity is achieved by the substantially + -shaped part 5 at the center and the four approximately V-shaped parts 6 connected to the respective tips of the approximately + -shaped part 5. In other words, it is not a simple shape such as a hexagon or a Y-shape, but a higher rigidity is achieved by a combination of the substantially + -shaped portion 5 and the substantially V-shaped portion 6 having high rigidity. Such a polyester long fiber is accumulated to prepare a flat polyester nonwoven fabric. In particular, high-rigidity flat polyester nonwoven fabric can be prepared by bonding the long polyester fibers by heat-sealing.

The polyester continuous fiber may be composed of one kind of polyester, but it is preferable to combine a low-melting polyester and a high-melting polyester. That is, it is preferable to use a composite type in which the substantially V-shaped portion 6 of the cross-sectional shape of the polyester long fiber is formed of low-melting polyester and the substantially + -shaped portion 5 is formed of high-melting polyester. This is because a flat polyester nonwoven fabric in which the polyester long fibers are heat-sealed with the low-melting polyester is obtained by softening or melting the low-melting polyester after solidifying the composite polyester continuous fibers and then solidifying the polyester. . Moreover, it is preferable that the fineness of the polyester continuous fiber which comprises a flat polyester nonwoven fabric is 10 decitex or more. When the fineness is less than 10 dtex, the rigidity of the long fibers tends to decrease, and as a result, the rigidity of the flat polyester nonwoven fabric tends to decrease. Moreover, it is preferable that the fabric weight of a flat polyester nonwoven fabric is 15-150 g / m < ² >. When the basis weight is less than 15 g / m ² , the flat polyester nonwoven fabric tends to have low rigidity. If the basis weight exceeds 150 g / m ² , the sound tends to be reflected, and the sound absorption effect tends to decrease. The details of the flat polyester nonwoven fabric used in the present invention are described in detail in Patent Document 2 described above.

The flat polyester nonwoven fabric is composed of the above-described polyester long fibers, and is generally produced by a spunbond method. The other uneven polyester nonwoven fabric used in the present invention is produced using this flat polyester nonwoven fabric. That is, it is manufactured by introducing a flat polyester nonwoven fabric between a pair of polka dot rolls. Here, the polka dot roll is a roll in which hemispherical convex portions and concave portions are alternately arranged on the peripheral surface. Specifically, it has the peripheral surface shown in FIGS. FIG. 3 is a plan view showing a part of the peripheral surface of the polka dot roll. 11 is a concave portion, 12 is a convex portion, and 13 is a flat portion. FIG. 4 is a vertical cross-sectional view taken along the line AA of the polka dot roll shown in FIG. 3 (a cross-sectional view taken along the axial direction of the polka dot roll from the line AA). The pitch between the concave portions and the convex portions may be arbitrary, but is generally about 5 to 10 mm. Moreover, although the depth of a recessed part and the height of a convex part may be arbitrary, generally it is about 0.5-1.5 mm. In this pair of polka dot rolls, one convex portion 12 meshes with the other concave portion 11, and one concave portion 11 meshes with the other convex portion 12 and rotates. When a flat polyester nonwoven fabric is passed between the pair of rotating polka dot rolls, a concavo-convex polyester nonwoven fabric having a concavo-convex pattern conforming to the peripheral shape of the polka dot roll is obtained. The linear pressure applied to the flat polyester nonwoven fabric by the pair of polka dot rolls is arbitrary, but is preferably about 50 to 100 kgf / cm. The pair of polka dot rolls is preferably heated, and the heating temperature is lower than the melting point of the polyester long fiber, and preferably about 100 to 170 ° C. The basis weight of the uneven polyester nonwoven fabric is preferably 15 to 150 g / m ² for the reason described above.

  The flat polyester nonwoven fabric obtained by the method described above is laminated on both sides of the uneven polyester nonwoven fabric obtained by the method described above. The flat polyester nonwoven fabric and the uneven polyester nonwoven fabric are bonded and integrated by an adhesive. A conventionally well-known thing is used as an adhesive agent. For example, a spider web, net or powder hot melt adhesive is used. The film-like hot melt adhesive has no problem if it melts and loses its film form.However, if the film form is maintained, sound is easily reflected or air permeability is impaired. It becomes difficult to use as a filter material. In the case of a hot melt adhesive such as a web shape, the hot melt adhesive is inserted between a flat polyester nonwoven fabric and an uneven polyester nonwoven fabric, and is bonded by applying pressure and heating. Since the flat polyester nonwoven fabric and the uneven polyester nonwoven fabric used in the present invention are highly rigid, they can be bonded without being compressed if they are pressed with a low load. A liquid pressure-sensitive adhesive, heat-sensitive adhesive, or curable adhesive may be used. In this case, it is preferable to apply a partial adhesive so as not to form a film. And what is necessary is just to apply | pressurize and heat and to adhere | attach as needed.

  The laminated form of the flat polyester nonwoven fabric and the uneven polyester nonwoven fabric has at least three layers, that is, a form in which the flat polyester nonwoven fabric is laminated on both surfaces of the uneven polyester nonwoven fabric, but may be a laminated form of three or more layers. For example, a flat polyester nonwoven fabric / concave polyester nonwoven fabric / flat polyester nonwoven fabric / concave polyester nonwoven fabric / flat polyester nonwoven fabric may be laminated in this order to form a five-layer laminate board, or both polyester nonwoven fabrics may be laminated to form a seven-layer laminate board or more. It is good.

  The laminated board obtained as described above is obtained by laminating a flat polyester nonwoven fabric 21 and an uneven polyester nonwoven fabric 22 as shown in FIG. And there exists a relatively small gap existing inside the flat polyester nonwoven fabric 21 and the uneven polyester nonwoven fabric 22, and a relatively large gap 23 formed between the flat polyester nonwoven fabric 21 and the uneven polyester nonwoven fabric 22, resulting in a high void state. ing. Such a laminated board can be suitably used as a sound absorbing material, a filter material, a building or civil engineering material.

  Since the high void laminate board obtained by the method according to the present invention has large and small voids, it has an effect of being excellent in sound absorption performance and filtration performance. In addition, the flat polyester nonwoven fabric and the uneven polyester nonwoven fabric forming the high-gap laminate board are each highly rigid, so they are difficult to be compressed and can maintain a state having large and small voids, resulting in decreased sound absorption performance and filtration performance. It also has the effect of being difficult.

[Manufacture of flat polyester nonwoven fabric]
Copolymerization was carried out using terephthalic acid (TPA) 92 mol% and isophthalic acid (IPA) 8 mol% as the dicarboxylic acid component, and ethylene glycol (EG) 100 mol% as the diol component, and a low-melting polyester (relative viscosity [ηrel] 1. 44, melting point 230 ° C.). To this low melting point polyester, 4.0% by mass of titanium oxide was added as a crystal nucleating agent to prepare a low melting point polyester resin. On the other hand, 100 mol% of terephthalic acid (TPA) as a dicarboxylic acid component and 100 mol% of ethylene glycol (EG) as a diol component were copolymerized to obtain a high melting point polyester resin (polyethylene terephthalate, relative viscosity [ηrel] 1.38, melting point 260). ℃) was prepared. Then, using the nozzle hole shown in FIG. 6, a low melting point polyester resin is supplied to the V-shaped part, and a high melting point polyester resin is supplied to the + -shaped part, and the spinning temperature is 285 ° C., the single hole discharge rate is 8.33 g / Melt spun in minutes. In addition, the weight ratio of the supply amount of the low melting point polyester resin and the supply amount of the high melting point polyester resin was 1: 2.

The filament group discharged from the nozzle hole was introduced into the air soccer entrance 2 m below and pulled so that the fineness of the composite polyester long fiber was 17 dtex. The composite polyester long fiber group discharged from the air soccer exit was opened with a fiber opening device and then collected on a moving net conveyor to obtain a fiber web. This fiber web is heat-fused with a flat roll and an embossing roll having a surface temperature of 213 ° C. (the area at the tip of each embossing protrusion is 0.7 mm ² and the area ratio of the embossing protrusion relative to the total area of the roll is 15%). The flat polyester nonwoven fabric having a basis weight of 120 g / m ² was obtained by introducing into a dressing apparatus and heat-sealing under the condition of a linear pressure of 30 kgf / cm between both rolls.

[Manufacture of uneven polyester nonwoven fabric]
A flat polyester nonwoven fabric was obtained by the same method as described above, except that the basis weight was 70 g / m ² . The flat polyester nonwoven fabric was passed through a pair of polka dot rolls to obtain an uneven polyester nonwoven fabric having an uneven pattern. Here, the polka dot roll has the concave portions and the convex portions shown in FIGS. 3 and 4, the pitch between the concave portions and the convex portions is 6.92 mm, the depth of the concave portions and the height of the convex portions. Is 0.9 mm. In addition, the pair of polka dots rolls are heated to 140 ° C., one concave portion is engaged with the other convex portion, one convex portion is engaged with the other concave portion and rotated, and the flat polyester nonwoven fabric is passed through. Got. The linear pressure of the pair of polka dot rolls was 66.7 kgf / cm.

[Manufacture of high void laminate board]
Next, on the smooth metal plate, the flat polyester nonwoven fabric and the uneven polyester nonwoven fabric produced by the above-described method are alternately laminated to form seven layers, and a melting point of 115 ° C. between each layer. A laminate was obtained by sandwiching a web-like hot melt adhesive sheet (weight per unit area: 25 g / m ² ) made of a polyamide resin. By placing a metal plate having a smooth surface on this laminate, it was left in a heat treatment apparatus at 150 ° C. for 2 minutes with a weight of 5 g / cm ² applied to the entire laminate, and the hot melt adhesive sheet The constituent resin was melted and the seven layers were adhered to obtain a laminated board having a basis weight of 855 g / m ² and a thickness of 5.98 mm. This laminated board was cut into a size of 18 cm × 18 cm to obtain a high void laminated board.

[Evaluation of sound absorption performance]
A specimen having a diameter of 28.7 mm was collected from the obtained high-gap laminate board, and the sound absorption coefficient was measured by the following two methods.

(Measurement of sound absorption rate 1)
With respect to three specimens, the sound absorption rate was measured for each frequency in the measurement frequency band 500 to 5000 HZ using a normal incident sound absorption rate measurement system WinZacMTX of Nippon Acoustic Engineering Co., Ltd., in accordance with the JISA 1405-2 transfer function method. And the average value of the sound absorption rate of three specimens was calculated and shown in Table 1.
[Table 1]
━━━━━━━━━━━━━━━━━━━
Frequency (Hz) Sound absorption rate (%)
━━━━━━━━━━━━━━━━━━━
500 4.55
630 5.19
800 6.09
1000 7.47
1250 9.06
1600 12.30
2000 17.39
2500 25.72
3150 35.76
4000 50.62
5000 71.00
━━━━━━━━━━━━━━━━━━━

(Measurement of sound absorption 2)
In a state where two specimens were overlapped, the sound absorption rate was measured for each frequency in the measurement frequency band 500 to 5000 HZ with a normal incident sound absorption rate measurement system WinZacMTX of Nippon Acoustic Engineering Co., Ltd., in accordance with the JISA 1405-2 transfer function method. The results are shown in Table 2.
[Table 2]
━━━━━━━━━━━━━━━━━━━
Frequency (Hz) Sound absorption rate (%)
━━━━━━━━━━━━━━━━━━━
500 9.49
630 12.30
800 16.67
1000 22.90
1250 31.59
1600 45.32
2000 60.77
2500 75.68
3150 85.22
4000 95.02
5000 90.12
━━━━━━━━━━━━━━━━━━━

[Evaluation of compression performance]
The specimen is sandwiched between round discs having a diameter of 60 mm, and an initial load of 1.96 kPa is applied to measure the thickness of the specimen. Thereafter, the load was increased to 0.98 to 21.55 kPa to increase it, and the reduction rate of the thickness of the specimen was determined. The results are shown in Table 3. The thickness reduction rate (%) is calculated by [(t0−t1) / t0] × 100. t0 is the thickness of the specimen when the initial load is applied, and t1 is the thickness of the specimen when the load is added.
[Table 3]
━━━━━━━━━━━━━━━━━━━━━━━
Load (kPa) Thickness reduction rate (%)
━━━━━━━━━━━━━━━━━━━━━━━
1.96 0
2.94 0.7
3.92 1.3
6.86 2.2
9.80 2.9
10.78 3.0
11.76 3.2
13.72 3.6
16.66 4.1
23.51 5.4
━━━━━━━━━━━━━━━━━━━━━━━

  From the results of Table 1 and Table 2, it can be seen that the high void laminate board obtained by the method according to the example is excellent in sound absorbing performance. In addition, it can be seen from the results in Table 3 that the high-gap laminated board obtained by the method according to the example is difficult to compress even when a load is applied. Therefore, when this high-gap laminate board is used as a sound-absorbing material, it retains high-gap even when compressed, and can maintain good sound-absorbing performance.

It is the figure which showed one substantially Y character of the substantially Y4 shape which is the cross-sectional shape of the polyester long fiber used by this invention. It is the figure which showed the substantially Y4 shape which is the cross-sectional shape of the polyester continuous fiber used by this invention. It is the top view which showed a part of peripheral surface of the polka dot roll used by this invention. It is the AA longitudinal cross-sectional view of the polka dot roll shown in FIG. It is a typical side view of the high-gap laminated board obtained by the manufacturing method according to an example of the present invention. It is the figure which showed the shape of the spinning hole used when manufacturing the flat polyester nonwoven fabric used in the Example.

DESCRIPTION OF SYMBOLS 1 Lower end of one substantially Y shape of the substantially Y4 shape which is the cross-sectional shape of a polyester continuous fiber 2 The recessed part formed in the substantially Y4 shape 3 The convex part formed in the substantially Y4 shape 4 The small recessed part formed in the substantially Y4 shape 5 About + character part in about Y4 shape 6 About V-shaped part in about Y4 shape 11 Concave part of polka dot roll 12 Convex part of polka dot roll 13 Flat part of polka dot roll 21 Flat polyester nonwoven fabric 22 Uneven polyester nonwoven fabric 23 Flat polyester nonwoven fabric and Gaps formed between layers of uneven polyester nonwoven fabric

Claims (4)

The cross-sectional shape is connected to the top, bottom, left and right at the lower end of the approximate Y-shape.

A step of producing a flat polyester non-woven fabric comprising polyester long fibers having a shape (hereinafter referred to as “substantially Y4 shape”);
A pair of polka dot rolls in which hemispherical convex portions and concave portions are alternately arranged on the peripheral surface, and a flat polyester is interposed between the pair of polka dot rolls that are engaged and rotated. Introducing a non-woven fabric to produce a polyester non-woven fabric having a concavo-convex pattern; and
A method for producing a high-gap laminated board comprising the steps of: laminating the flat polyester nonwoven fabric on both sides of the polyester nonwoven fabric having a concavo-convex pattern, and bonding the laminated layers with an adhesive.   The polyester long fiber is a composite type polyester long fiber in which each substantially V-shaped portion of a substantially Y4 shape is made of a low-melting polyester, and the other substantially + -shaped portion is made of a high-melting polyester, 2. The method for producing a high-gap laminated board according to claim 1, wherein a flat polyester nonwoven fabric in which the composite polyester long fibers are bonded to each other by bonding is used.   The method for producing a high-gap laminated board according to claim 1, wherein a spider web-like or net-like hot melt adhesive is used as the adhesive.   The method for producing a high-gap laminated board according to claim 1, wherein a pair of heated polka dot rolls is used.

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