JP2006175821A - Inner packaging material sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet for an inner packaging material which can prevent penetration of a resin even if unit weight is lightened, can be deep-drawn, and is easily peeled. <P>SOLUTION: The inner packaging material sheet (10) has the sheets (2a and 2b) for the inner packaging material placed between the surface layer (1) and the base resin layer (3), wherein the sheets (2a and 2b) for the inner packaging material keeps a fiber layer (2a) overlying at least one surface of the paper layer (2b) containing liquid-retainable fiber, the paper layer (2b) and the fiber layer (2a) being integrated into one body. The inner packaging material sheet shows air permeability of not less than 10 cm<SP>3</SP>/(cm<SP>2</SP>s) to not more than 150 cm<SP>3</SP>/(cm<SP>2</SP>s) measured according to JIS L1096 6.27.1 method A (Frazier method) of an inner packaging material. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is a non-woven fabric that has a function of preventing adhesive and molten resin from bleeding and a resin molding function, and can reduce the weight of the material. It is related with the sheet | seat for interior materials which can be used for such as.

An interior material that intervenes as a barrier layer between an outer skin layer and a base resin layer is used for a back base fabric of a vehicle interior, a back base fabric of furniture, and the like. For example, an interior material used for an automobile ceiling or the like is integrally formed with a skin layer such as tricot, a cushion layer, a barrier layer, and a base resin layer as viewed from the indoor side. That is, for example, a polypropylene resin is used as the base resin layer, and the molding is performed at the final stage to perform integral molding. For this reason, it is necessary to make the base material resin difficult to permeate into the cushion material, and in Patent Document 1 below, a polyester nonwoven fabric sheet that has been hydroentangled after paper making is used as a barrier material.
JP 2000-108233 A

  However, the conventional technique has a problem that when the viscosity of the resin is low, the molten resin or monomer easily penetrates into the nonwoven fabric. Moreover, since it is comprised with a short fiber, it is easy to fracture | rupture with low elongation, and in the case of shaping | molding, such as deep drawing, there existed a possibility that the nonwoven fabric might be destroyed. Further, when there is a roof window or the like, it is necessary to remove the base resin layer and fold only the skin layer to perform edge treatment, but there is also a problem that it is difficult to peel off with a polyester nonwoven fabric sheet.

  In order to solve the above-described conventional problems, the present invention can prevent penetration of the resin even when the basis weight is lightened, and can perform deep drawing.

  Furthermore, when there is a roof window or the like, an interior material sheet that can be easily peeled can be provided.

The interior material sheet of the present invention is an interior material sheet interposed between the skin layer and the base resin layer, and the interior material sheet has fibers on at least one side of a paper layer containing liquid retaining fibers. The paper layer and the fiber layer are integrated, and the air permeability of the interior material sheet in JIS L1096 6.27.1 A method (Fragile method) is 10 cm ³ / cm ² · s. It is a range of 150 cm ³ / cm ² · s or less.

Since the interior material sheet of the present invention is composed of a fiber layer and a paper layer containing liquid retaining fibers, the fiber layer can be deep drawn while maintaining strength, and the paper layer containing liquid retaining fibers is resin molded. It becomes a structure in which the molten resin and monomer at the time hardly penetrate. The fiber layer and the paper layer are integrated, and an air permeability in the JIS L1096 6.27.1 A method (Fragile method) of the interior material sheet is 10 cm ³ / cm ² · s or more and 150 cm ³ / cm ^2. -Since it is in the range of s or less, the basis weight is light and the penetration of the resin can be stopped. In addition, a fiber layer that has been entangled with water in advance and entangled and integrated with a paper layer containing liquid-retaining fibers can be peeled off between the two layers.

  The interior material sheet of the present invention is interposed between the skin layer and the base resin layer, and is composed of a fiber layer and a paper layer containing liquid retaining fibers. The skin layer refers to, for example, a skin, a material obtained by backing a resin film or a nonwoven fabric on the skin, a material obtained by integrating a skin and a cushion layer, and the like. The base resin layer refers to, for example, an adhesive, a curable liquid resin, a thermoplastic resin, and the like. For the fiber layer, for example, a single fiber card web of synthetic fibers is used. For example, tissue paper or crepe paper is used as the paper layer containing the liquid retaining fiber. The fiber layer and the paper layer are integrated. The integration method is not particularly limited, and examples thereof include thermocompression bonding using an embossing roll, ultrasonic bonding, and bonding using a resin such as powder. In particular, the integration by the hydroentanglement method is advantageous in that it has moderate elongation because it is partially entangled and integrated in the machine direction (row direction).

  In order to partially entangle and integrate in the row direction, for example, pressurized water is jetted in the row direction to perform water flow entanglement processing. The distance between the rows is preferably about 0.4 to 5 mm. The water pressure in the hydroentanglement treatment is preferably in the range of 1 to 10 MPa. By this hydroentanglement process, hydroentanglement traces with a width of 0.6 mm or less are formed in a streak pattern in the length direction (MD direction) of the paper layer. In this hydroentanglement trace, low fiber accumulation regions and high fiber accumulation regions alternately exist in the adjacent portions. Such a low fiber accumulation region can be formed by applying a columnar water flow to the paper layer surface. Here, the low fiber accumulation region refers to a portion where the paper layer is thinned or broken by hydroentanglement, and refers to a portion where the amount of accumulated fibers per unit area is small. The high fiber accumulation region refers to a portion where the amount of accumulated fibers per unit area is large compared to the low fiber accumulation region, and is defined by the relative relationship between the two regions. The amount of accumulated fibers can be determined from the number of constituent fibers. Further, by visual observation, the low fiber accumulation region and the high fiber accumulation region may be easily grasped from the difference in the transparency of the paper layer. The width of the low fiber accumulation region is preferably 0.6 mm or less. If it is wider than 0.6 mm, the base resin may ooze out from there. More preferably, it is 0.5 mm or less, Most preferably, it is 0.3 mm or less. Especially, the fiber layer entangled with the paper layer after hydroentanglement in advance has sufficient non-woven strength as a sheet for interior materials at the time of preliminary entanglement. Water pressure can be reduced, and the fiber layer is dense due to pre-entanglement, so even if the water pressure is the same when entangled with the paper layer, the paper layer breaks (scatters) This is preferable because the width is reduced and the width of the low fiber accumulation region can be reduced. The width of the low fiber accumulation region is calculated by an arbitrary average value of five points in the low fiber accumulation region with a small amount of paper layer fibers within the range of 2 mm in length and 2.5 mm in the scanning electron micrograph. A more preferable range of the water pressure is 2 to 8 MPa. If the pressure is lower than 1 MPa, the fiber entanglement is weak, and the nonwoven fabric may be broken at a low elongation. If the pressure is higher than 10 MPa, the paper layer is greatly broken and the air permeability may be increased.

Due to the presence of the low fiber accumulation region, the integrated nonwoven fabric has an appropriate stretchability (flexibility), and the followability of the (R) portion at the time of molding processing is improved, and the molding processability is improved. It becomes a good non-woven fabric. Although the barrier property varies depending on the width of the low fiber accumulation region, in order to have a preferable barrier property, the air permeability in JIS L1096 6.27.1 A method (Fragile method) is 10 cm ³ / cm ² · s or more and 150 cm. ^It is good to set it as the range below ³ / cm < ² > * s.

  In the above, the paper layer containing the liquid retaining fiber preferably contains cellulosic fibers such as pulp and rayon, more preferably 30% by mass or more, and further preferably 50% by mass or more. The mass ratio of the fiber layer to the paper layer is preferably in the range of fiber layer: paper layer = 1: 1.5 to 5: 1, and more preferably in the range of fiber layer: paper layer = 1: 1 to 5: 1. preferable.

  The fiber layer and the paper layer are integrated by hydroentanglement, but can be peeled off from both layers.

The paper layer containing the liquid retaining fiber has a dense fiber structure and excellent resin barrier properties. Further, even if the resin penetrates, the density is high, so that it diffuses and absorbs quickly and does not ooze out to the other surface. The material is not particularly limited as long as it has a dense structure, but paper obtained by a wet papermaking method is preferable because of its high density. Liquid-retaining fibers have the function of holding liquids such as adhesives and molten resins in the fibers themselves, natural fibers such as cotton, recycled fibers such as rayon and cupra, solvent-spun cellulose fibers, It includes at least one kind of fibers such as hydrophilic fibers such as pulp and synthetic fibers such as polyester, nylon and acrylic fibers. Of these, cellulosic fibers are preferred. When cellulosic fibers are included, when an adhesive resin having a low viscosity is used, the resin is quickly absorbed and diffused, and there is no possibility that the resin will ooze out locally. In addition, even when the amount of resin is large, the holding ability is high, so there is no need to increase the basis weight and the weight can be reduced, which is preferable as a barrier material. In particular, cellulose pulp paper having a low air permeability is preferable because it has excellent resin barrier properties. Basis weight is preferably from ^{10~50g / m 2, 20~40g / m} 2 is more preferable. If it is lower than 10 g / m ² , the function as a barrier layer may be insufficient, and if it is higher than 50 g / m ^2, hydroentanglement with the fiber layer may be insufficient. In the case other than pulp paper, the fineness of the fiber is preferably 0.7 to 3.3 dtex, more preferably 0.7 to 2.2 dtex. If it is thinner than 0.7 dtex, the processability is deteriorated, and if it is thicker than 3.3 dtex, the denseness is deteriorated. The air permeability is more preferably 5 to 90 cm ³ / cm ² · s in the JlSL-1096 6.27.1 A method. In addition, the interior material sheet of the present invention has a dense structure in which the paper layer containing the liquid retaining fibers absorbs and diffuses the resin quickly, and there is no risk of the resin oozing out locally, and there are many resins. However, since the holding ability is high, the method of using the paper layer so as to be in contact with and integrated with the base resin layer side is particularly preferable when used as a part of the interior material.

The fiber layer also has a resin barrier function, but this function largely depends on the basis weight. The main function of this layer is the extensibility (flexibility) of the nonwoven fabric. When performing complex molding processing, it is necessary to have moderate stretchability (flexibility) to follow the bent (R) part, and if there is no stretchability (flexibility), it becomes a habit. Or the nonwoven fabric may be destroyed and the resin may ooze out. The material is not particularly limited. Considering the temperature of the molding resin, acrylic fiber, polyester fiber, nylon fiber, and the like are preferable in terms of a high melting point. In particular, polyester fibers are more preferred because of their high extensibility (flexibility). The fiber structure is not particularly limited, and may be a single component fiber, or a core-sheath composite fiber or split fiber. Basis weight of the fiber layer, 30~90g / m ² is preferred.

More preferably, it is 30-80 g / m < ² >, Most preferably, it is 40-70 g / m < ² >. If it is lower than 30 g / m ² , the formation becomes worse and the resin may ooze out. The fineness of the single fiber is preferably in the range of 0.7 to 6.6 dtex. More preferably, it is 0.9 to 3.3 dtex. If it is thinner than 0.7 dtex, the processability is deteriorated. If it is thicker than 6.6 dtex, the entanglement of the fibers is deteriorated, and the nonwoven fabric may be broken at a low elongation. The production method of the fiber layer is not particularly limited as long as it does not break at low elongation. Parallel card method, semi-random card method, cross-laid method, airlaid method, spunbond method, melt blow method, flash spinning method, etc. May be obtained by at least one method obtained from the above, but those obtained by at least one method of a parallel card method, a semi-random card method, a cross-laid method, and an airlaid method are preferred.

  The interior material sheet of the present invention is a laminate of a fiber layer and a paper layer. Even if the fiber layer and the paper layer are individually used, it is impossible to achieve both barrier properties and molding processability, and this function can be made compatible only by laminating them. The fiber layer and the paper layer are entangled and integrated in order to achieve both proper extensibility (flexibility) and resin barrier properties at the time of molding, but the fiber layer is previously hydroentangled and the liquid retaining fiber is The method of confounding and integrating with the paper layer containing is preferred, the method of hydroentangled the fiber layer in advance, superimposing the paper layer containing liquid retaining fibers on the top surface of the hydroentangled nonwoven fabric, and the method of hydroentangled from the paper layer side is the most preferable.

  If the fiber layer and the paper layer are directly laminated and bonded together, the amount of fibers falling in the paper layer is large, the air permeability increases, and the resin may ooze out. Further, since the stress in the direction perpendicular to the sheet length direction (CD direction) is insufficient with respect to the target elongation, the nonwoven fabric may be destroyed and the resin may ooze out during the molding process. In addition, when the paper layer is laminated on the lowermost surface, the amount of fibers dropped off from the paper layer is larger than when the paper layer is laminated on the middle layer or the upper surface, and the resin may ooze out.

  For this reason, the paper layer is preferably laminated on the middle layer or the upper surface (the surface in contact with the base resin layer).

As for the fabric weight of the sheet | seat for interior materials of this invention, 40-120 g / m < ² > is preferable. Moreover, since the resin barrier property is required, the air permeability of the sheet for interior material is preferably 10 to 150 cm ³ / cm ² · s in the JIS L 1096 6.27.1 A method, and 10 cm ³ / cm ² · s. More preferably, it is 100 cm ³ / cm ² · s. In addition, since extensibility (flexibility) is required at the time of molding, the stress at 10% elongation in the CD direction is 1.5 to 10 N / 50 mm in the JIS L-1096 6.12.1A method (strip method). It is preferable that it is 1.5-6N / 5cm. Furthermore, the peel strength between the fiber layer and the paper layer is preferably 10 N / 50 mm or less.

  Next, it demonstrates using drawing. 1A-B are examples of an interior material 10 for an interior ceiling of an automobile, for example, in which the interior material sheet of the present invention is used. In FIG. 1A, 1 is a skin layer on the indoor side, 1a is a skin, and 1b is a cushion layer. 2a and 2b are interior material sheets according to an embodiment of the present invention, 2a is a synthetic fiber nonwoven fabric layer, and 2b is a paper layer containing cellulose pulp. 3 is a base resin layer. The interior material 10 is formed by integrating the skin 1a, the cushion layer 1b, and the interior material sheets 2a, 2b and the base resin layer 3 by bonding with an adhesive. As another molding method, the sheets may be stacked and placed in a mold, heated and deep-drawn into a predetermined shape to be integrated. FIG. 1B is different from FIG. 1 in that a synthetic fiber nonwoven fabric layer 2 a ′ is further interposed between a paper layer 2 b containing cellulose pulp and the base resin layer 3. In the case of FIG. 1A, peeling is possible between the synthetic fiber nonwoven fabric layer 2a and the paper layer 2b containing cellulose pulp. In the case of FIG. 1B, the synthetic fiber nonwoven fabric layer 2a ′ and the paper layer 2b containing cellulose pulp Or between the paper layer 2b containing cellulose pulp and the synthetic fiber nonwoven fabric layer 2a.

  This will be described below with reference to examples. The present invention is not limited to the following examples.

(Examples 1-5, Comparative Examples 1-8)
(1) Synthetic fiber nonwoven fabric layer Polyethylene terephthalate (PET), fineness: 1.6 dtex, fiber length: 51 mm (manufactured by Toray Industries, Inc., product number T471), parallel card web, basis weight: 30 g / m ² , 40 g / m ² , 50 g / M ² was used.
(2) Paper layer Crepe paper (manufactured by Daifuji Paper Co., Ltd.), basis weight: 15 g / m ² and 22 g / m ² were used.
(3) Hydroentanglement The nozzle used has an orifice diameter of 0.12 mm. The pitch was 0.6 mm and the water pressure was 3 MPa.
(4) Drying treatment Using a hot-air penetrating cylinder dryer, the temperature was 140 ° C. and the time was 30 seconds.
(5) Water Flow Treatment Method FIG. 2A is a process diagram showing a method for producing an interior material sheet in one embodiment of the present invention. The fiber layer 2a is supplied from a fiber layer forming apparatus (card, not shown), the paper layer 2b is supplied from the supply roll 12, the both are laminated, and the metal mesh plate 16 is passed through. Then, the pressurized water 14 is sprayed from the water flow nozzle 13, the synthetic fiber nonwoven fabric layer 2 a and the paper layer 2 b are entangled and integrated, dried by a dryer 18, and then wound on a winding roll 15.

  FIG. 2B is a process diagram showing a method for manufacturing a three-layer interior sheet according to another embodiment of the present invention. The paper layer 2b is supplied from the supply roll 12, the fiber layers 2a and 2a 'are supplied from a fiber layer forming device (card, not shown), the paper layer 2b is sandwiched, and the metal mesh plate is laminated in three layers. 16, the pressurized water 14 is jetted from the water flow nozzle 13 pressurized on this, the paper layer 2 b and the synthetic fiber nonwoven fabric layers 2 a and 2 a ′ on both sides thereof are entangled and integrated, and dried by the dryer 18. Winding up on a winding roll 15.

FIG. 3 is a process diagram showing a method for manufacturing an interior material sheet in still another embodiment of the present invention. A non-woven fabric that is supplied with a fiber layer 2a from a fiber layer forming device (card, not shown), sprays pressurized water 14 from a water flow nozzle 13 pressurized on a metal mesh plate 16, performs entanglement treatment, and then entangles. The paper layer 2b supplied from the supply roll 12 is overlaid on the upper surface of the paper, and the pressurized water 14 is jetted from the water nozzle 13 pressurized on the metal mesh plate 16 from the paper layer 2b side. The layers 2b are entangled and integrated, dried by a dryer 18, and then wound up on a winding roll 17. If it does in this way, a big hole will not be provided in the sheet | seat for interior materials by a water flow, and the air permeability can be made low, and the peelability between the fiber layer 2a and the paper layer 2b after interior material molding will become favorable.
(6) Physical property test The fabric weight, air permeability, peel strength, tensile strength, 10% stress and elongation of the treated product were measured.
(A) Weight per unit: According to JIS L 1096 6.12.1 A method.
(B) Air permeability: According to JIS L 1096 6.27.1 A method (Fragile method). The air permeability correlates with the permeability of the molten resin or monomer at the time of resin molding, and if it is high, it tends to ooze out.
(C) Tensile strength, 10% stress and elongation: in accordance with JIS L-1096 6.12.1 A method. Tensile strength, 10% stress, and elongation are related to deep drawability, and good formability is obtained in an appropriate range.
(D) Peel strength: The sample was cut to a length of 15 cm in length and 5 cm in width, and a cloth adhesive tape (No. 750, manufactured by Nitto Denko Corporation) was attached to the paper layer side, and the load was 250 g from the cloth adhesive tape side. After reciprocating the roller so as to be 1 cm / cm, the paper layer and the fiber layer of the sample are peeled 5 cm in the vertical direction and attached to Tensilon (UCT-IT Orientec Co., Ltd.) with a grip width of 2.5 cm. The 6-point average value of the maximum 3 points and the minimum 3 points when peeling 5 cm at a head speed of 100 mm / min is defined as the peel strength. The peel strength indicates the peelability of the sheet for interior material after molding.

  The above conditions are shown in Table 1, and the results are shown in Table 2.

  In Table 2, MD indicates the length direction (winding direction) of the interior material sheet, and CD indicates the width direction.

  The surface photograph (magnification 50) observed from the crepe paper side of the sheet for interior material obtained in Example 1 is shown in FIG. 4, and the surface observed from the crepe paper side of the sheet for interior material obtained in Example 2 A photograph (magnification 50) is shown in FIG.

  As is clear from Table 2, Examples 1 to 5 all showed preferable air permeability, 10% stress and elongation. This makes it difficult for the molten resin and monomers to penetrate during resin molding, deep drawing is possible, and it can be peeled off between the fiber layer and the paper layer containing liquid-retaining fibers except for Example 5. Met.

  On the other hand, Comparative Example 1 had high air permeability and was easily penetrated by the molten resin or monomer at the time of resin molding, and could not be peeled off between the fiber layer and the paper layer containing liquid retaining fibers.

  In Comparative Example 2, the air permeability was high and the molten resin or monomer during resin molding was easy to penetrate.

  The comparative example 3 showed the comparison with Example 3, and the air permeability was high and the molten resin and monomer at the time of resin molding were easy to osmose | permeate.

  Comparative Example 4 shows a comparison with Example 1 and has a high air permeability and allows easy penetration of the molten resin and monomer during resin molding, and is difficult to peel between the fiber layer and the paper layer containing liquid retaining fibers. Met.

  The comparative example 5 showed the comparison with Example 2, and the air permeability was high and the molten resin and monomer at the time of resin molding were easy to osmose | permeate.

  Since the paper layer was not used for the comparative example 6, the air permeability was high and the molten resin and monomer at the time of resin molding permeate | transmitted easily, and it was not able to peel.

  Since Comparative Example 7 did not use a fiber layer, the tensile strength, 10% stress and elongation were low, deep drawing could not be performed, and peeling was not possible. In addition, although injection of pressurized water was tried, it scattered and the shape of the crepe paper was not maintained.

  In Comparative Example 8, although the air permeability was low, deep drawing could not be performed due to high 10% stress and low elongation.

  As described above, the sheet for interior material of each example of the present invention is a laminate of a paper layer and a fiber layer containing liquid retaining fibers, and prevents exudation of resin such as adhesive and resin. Since it also has extensibility (flexibility), the nonwoven fabric is stretched moderately without being broken in the CD direction, and complicated molding such as deep drawing can be easily performed.

FIG. 1A is a cross-sectional view of an automotive interior material as a two-layer interior material sheet according to an embodiment of the present invention. FIG. 1B is a cross-sectional view of an automotive interior material that is a three-layer interior material sheet according to an embodiment of the present invention. FIG. 2A is a process diagram showing a method for producing a two-layer interior material sheet in one embodiment of the present invention. FIG. 2B is a process diagram illustrating a method for producing a three-layer interior material sheet according to another embodiment of the present invention. FIG. 3 is a process diagram showing a method for producing a two-layer interior material sheet in still another embodiment of the present invention. FIG. 4 is a surface photograph (magnification 50) observed from the crepe paper side of the interior material sheet obtained in Example 1 of the present invention. FIG. 5 is a surface photograph (magnification 50) observed from the crepe paper side of the interior material sheet obtained in Example 2 of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Skin layer 1a Skin 1b Cushion layer 2a, 2a 'Synthetic fiber nonwoven fabric layer 2b of interior sheet Paper layer 3 containing cellulose pulp of interior sheet Base resin layer 10, 20 Interior material 12 Supply roll 13 Water nozzle 14 Pressurized water 15, 17 Winding roll 16 Metal mesh plate 18 Dryer

Claims (11)

An interior material sheet interposed between the skin layer and the base resin layer,
The interior material sheet has a fiber layer laminated on at least one side of a paper layer containing liquid retaining fibers, and the paper layer and the fiber layer are integrated,
The interior material sheet has an air permeability in the range of 10 cm ³ / cm ² · s to 150 cm ³ / cm ² · s in JIS L1096 6.27.1 A method (Fragile method). Sheet.   The interior material sheet according to claim 1, wherein the liquid retaining fiber is a cellulosic fiber.   The interior material sheet according to claim 1, wherein the liquid retaining fiber is cellulose pulp.   The interior material sheet according to claim 1, wherein the fiber layer and the paper layer are overlapped and hydroentangled.   The interior material sheet according to claim 4, wherein the fiber layer is entangled with water in advance and entangled with a paper layer containing liquid retaining fibers.   6. The interior material according to claim 4, wherein the fiber layer is hydroentangled in advance, a paper layer containing liquid retaining fibers is superimposed on an upper surface of the obtained hydroentangled nonwoven fabric, and hydroentangled from the paper layer side. Sheet.   7. The interior material according to claim 4, wherein the fiber layer and the paper layer are overlapped and hydroentangled, and a streaky hydroentanglement trace is present in a length direction of the paper layer. Sheet.   10% stress in a direction perpendicular to the length direction of the sheet in JIS L-1096 6.12.1 A method (strip method) of the sheet for interior material is in a range of 1.5 to 10 N / 50 mm. Item 12. The sheet for interior material according to Item 1. 2. The interior according to claim 1, wherein the interior material sheet has an air permeability in a range of 10 cm ³ / cm ² · s to 100 cm ³ / cm ² · s in JIS L1096 6.27.1 A method (Fragile method). Material sheet.   The interior material sheet according to claim 1, wherein the sheet can be peeled between the fiber layer and the paper layer, and the peel strength is 10 N / 50 mm or less. The sheet for interior materials is interposed between the skin layer and the base resin layer, and the paper layer containing the liquid retaining fiber is in contact with and integrated with the base resin layer surface. Interior material according to crab.

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