JP6527791B2 - Method of manufacturing exterior soundproofing material for vehicle - Google Patents

Description

  The present invention relates to an automobile exterior material. In particular, the present invention relates to automobile exterior materials such as fender liners, engine undercovers, etc., such as fender liners capable of alleviating collision noises such as sand and pebbles that the tire jumps up, and easily adhering ice being separated The present invention relates to a method of manufacturing an exterior soundproofing material for a vehicle.

  As an exterior soundproofing material for vehicles, one provided with a non-woven fabric in which many short fibers are intertwined with each other is known. The exterior soundproofing material for vehicles made of non-woven fabric has impact resistance and sound absorbing properties, but the sound insulation performance is low because the innumerable gaps formed between the intertwined fibers absorb the impact due to the collision of foreign matter. Soundproofing performance is not enough. Furthermore, since the water adhering to the exterior soundproofing material for a vehicle penetrates to the inside, when the water is frozen, there is a problem that the ice grows to the inside and becomes difficult to separate.

  For that purpose, for example, in Patent Document 1, the under protector as a sound absorbing material for automobile exterior is provided with a non-woven fabric that exhibits high sound absorbing performance. This non-woven fabric is formed by press-forming a sheet-like non-woven fabric in which main fibers and binder fibers having a melting point lower than that of the main fibers are entangled. Furthermore, the surface of the non-woven fabric is coated with a water-resistant film. The water-resistant film is adhered to the lower surface of the non-woven fabric in a state of being fused with the binder fiber by being press-formed in a state of being in close contact with the surface of the sheet-like non-woven fabric at the time of forming the non-woven fabric.

  It is also known to produce water-resistant thin films on the surface of nonwovens by other methods. For example, in Patent Document 2, as a sound absorbing material in a high temperature atmosphere such as an engine cover sound absorbing material or an engine under cover, it is made of a non-woven fabric formed by laminating a ventilation control layer of polyester fiber and a sound absorbing layer of polyester fiber. Thus, the surface of the ventilation control layer is made to be a thin film processing by heating and pressing. Specifically, the ventilation control layer and the sound absorbing layer are laminated and integrated by a needle punch, and the united one is passed between the metal heating roller and the rubber roller so as to thin the surface of the ventilation control layer. ing.

  Moreover, in patent document 3, it is a nonwoven fabric sound absorbing material which consists of a matrix fiber of PET and a heat-fusion fiber of PET of a core-sheath structure as an interior material of a car, and the surface becomes a film by heat treatment. In the manufacturing method, one side of the non-woven fabric composed of matrix fibers and heat fusion fibers is pressed with a heating roller or a heating plate to form a thin film.

JP 2002-348767 A JP, 2009-249803, A JP, 2000-199161, A

  In patent document 1, only a water-resistant film is accumulated on one surface of a sheet-like nonwoven fabric, and deformation resistance runs short. In addition, since water adhering to the surface not provided with the water resistant film penetrates to the inside, when the water is frozen, there is also a problem that ice grows up to the inside and it becomes difficult to peel off. Furthermore, since the water resistant film is fused and bonded to the binder fiber by press forming in a state where the water resistant film is overlapped on the surface of the sheet-like non-woven fabric, the water resistant film is It is necessary to have a melting point higher than that of the binder resin, resulting in limitations on the selection of water-resistant film materials.

  In Patent Document 2, the ventilation control layer and the sound absorbing layer pass the polyester copolymer fiber (melting point 130 ° C.) between the metal heating roller (heating temperature 160 ° C., roller pressure 170 kg / cm) and the rubber roller, and the ventilation control layer. A thin film is formed on the surface of the non-woven fabric sheet, but since the non-woven fabric sheet is heated again to 200 ° C. in order to form the three-dimensional shape of the vehicle exterior material, the intentionally formed thin film is broken and eliminated.

  In Patent Document 3, since a thin film is formed by pressing one side of the non-woven fabric composed of the matrix fiber and the heat-fusion fiber with a heating roller or a heating plate, a flat non-woven sheet can be obtained. However, forming the three-dimensional shape of the vehicle exterior material is not disclosed.

  The present invention has been made in view of such problems existing in the prior art, and is configured so that it can be easily formed into a three-dimensional shape of a vehicle exterior soundproofing material, and an anti-icing property And providing a vehicle exterior soundproofing material capable of exhibiting high soundproofing performance.

  In the present invention, a thin film capable of achieving water repellency and anti-icing properties is formed on the surface of the non-woven fabric, and this thin film can be molded into a predetermined shape while remaining, and a vehicle exterior soundproofing material excellent in deformation resistance is obtained. I was able to

Specifically, the invention according to claim 1 is a method of manufacturing a vehicle exterior soundproofing material, comprising: a base material layer having a sound absorbing action; and a reinforcing layer integrally provided on both sides of the base material layer ,
The material of the base layer is a sheet-like base nonwoven fabric in which a first fiber made of polypropylene resin fiber and a second fiber made of binder fiber having a melting point lower than that of the polypropylene resin are entangled.
The material of the two reinforcing layers is made of the same sheet-like reinforcing non-woven fabric in which first fibers made of polypropylene resin fibers and second fibers made of binder fibers having a melting point lower than that of the polypropylene resin are entangled. ,
The nonwoven fabric for the base material has a high basis weight as compared to each reinforcing nonwoven fabric,
The non-woven fabric for a substrate is a non-woven fabric containing a smaller amount of the first fibers and a larger amount of the second fibers as compared to the reinforcing non-woven fabrics,
Producing a sheet material of a three-layer structure in which the reinforcing non-woven fabric is laminated on both sides of the base non-woven fabric,
The sheet material is heated and pressed with a press die consisting of a heated flat plate-shaped heat plate, and the reinforcing sheet in contact with the heat plate. Producing a flat plate-like member formed by respectively forming a reinforcing film on the outer surface of the non-woven fabric,
While being heated by the heat plate, the flat plate member is cooled while being pressurized by a cooling mold, and a molded article of a predetermined three-dimensional shape is left while leaving the reinforcing film on the outer surface of both reinforcing layers. Molding.

  The invention according to claim 2 is the method according to claim 1, wherein the flat plate member is cooled and formed while the flat plate member is in a state where it can be formed into a three-dimensional shape with a heated state by heating of the heat plate remaining. It is characterized in that it is cooled while being pressurized by a mold and molded into a molded article of a predetermined three-dimensional shape while leaving the reinforcing film on the outer surface of both reinforcing layers.

  The invention of claim 3 is characterized in that, in claim 1 or 2, the heat plate is heated by a heater.

  The invention of claim 4 is characterized in that, in any one of claims 1 to 3, the cooling mold is cooled by cooling water.

  The invention of claim 5 is characterized in that, in any one of claims 1 to 4, the binder fiber is a PET resin.

In the invention of claim 6, in any one of claims 1 to 5, the base material non-woven fabric has a basis weight of 400 to 800 g / m ² , and the first fiber is 20 to 40% by weight, The second fiber comprises 80 to 60% by weight, each reinforcing nonwoven fabric has a basis weight of 100 to 300 g / m ² , the first fiber is 60 to 90% by weight, and the second fiber is 40 to It is characterized in that it consists of 10% by weight.

  The invention according to claim 7 is that, in any one of claims 1 to 6, when heating and pressurizing the sheet material by sandwiching the heat plate of the press die, the heating temperature of the heat plate is 180 to 240. C., the thickness of the sheet material after pressing / the thickness before pressing = 0.9 to 0.85 times the thickness ratio, and the pressing time is 20 to 60 seconds. Do.

  In the invention of claim 8 according to any one of claims 1 to 7, the thickness of the vehicle exterior soundproofing material is 3.5 to 5.0 mm, and the thickness of the reinforcing film is 150 to 300 μm. It is characterized by

  The invention according to claim 9 is characterized in that, in any one of claims 1 to 8, the binder fiber has a core-sheath structure, the core part is a high melting point PET resin, and the sheath part is a low melting point PET resin. I assume.

  According to the first aspect of the present invention, since it can be formed into a predetermined three-dimensional shape while leaving the reinforcing film formed by heating and pressing, the formed reinforcing film can be formed while remaining without breaking. it can. By providing the same reinforcing layer on the both surfaces and providing the same reinforcing film on the outer surface, deformation resistance and rigidity are enhanced, and chipping resistance and icing resistance required as an exterior soundproofing material for a vehicle are provided and high. Soundproof performance can be demonstrated.

  According to the second aspect of the present invention, there is no need to heat the flat sheet again in order to form a three-dimensional shape, so the number of holes in which the reinforcing film once generated breaks or disappears due to reheating increases. Alternatively, problems such as an increase in fine holes can be prevented. Moreover, since there is no reheating step, the cost can be reduced.

  According to the invention of claim 3, since the heating plate is heated by the heater, the sheet material can be heated to a uniform temperature in a short time, and a reinforcing film can be formed in a short time in a portion in contact with the heating plate. It can be produced with almost uniform thickness and uniform ventilation.

  According to the invention of claim 4, since the cooling mold is cooled by the cooling water, it is easy to control the balance between the cooling rate and the three-dimensional molding shape, and the reinforcement film is left. , Can be formed into a predetermined three-dimensional shape.

  According to the fifth aspect of the present invention, since the binder fiber is a PET resin, it can be entwined with the PP resin to form an integral shape, and the vehicle exterior soundproofing material can be lightweight and excellent in sound absorption and obtained at low cost.

  According to the invention of claim 6, by specifying the weight per unit area of the nonwoven fabric for base material and the nonwoven fabric for reinforcement and the ratio of the first fiber and the second fiber, the exterior for a vehicle is excellent in sound absorption and lightweight at low cost. Soundproofing material can be easily obtained.

  According to the invention of claim 7, by setting the forming conditions when heating and heating the sheet material with a press mold, it is possible to integrally obtain a flat sheet having a three-layer structure which is uniformly bonded, as well as reinforcement. A reinforcing membrane can be reliably obtained on the outer surface of the layer at a predetermined thickness and in a predetermined vented state.

  According to the invention of claim 8, by specifying the thickness of the exterior soundproofing material for a vehicle and the thickness of the reinforcing film, it is possible to obtain a lightweight exterior soundproofing material for a vehicle which is further excellent in sound absorption and lightweight.

  According to the ninth aspect of the present invention, the reinforcing membrane can be reliably obtained at a predetermined thickness and in a predetermined ventilated state, and a film excellent in sound absorption can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS It is a principal part side view which shows the front part of the vehicle which attached the fender liner as an example of the exterior soundproof material for vehicles which concerns on Embodiment 1 of this invention. It is an II-II line expanded sectional view of Drawing 1, and shows a fender liner and its peripheral portion. In the manufacturing process of the exterior soundproofing material for vehicles of Embodiment 1, it is a figure showing typically the manufacture device which laminates a reinforcement layer on both sides of a substrate layer, and forms primary lamination sheet material A. It is the elements on larger scale sectional drawing of sheet material A of the three-layer structure obtained in FIG. It is a figure which shows the manufacturing process of the exterior soundproofing material for vehicles of Embodiment 1, (A) is a figure which shows the state which mounted the sheet material A in the flat press die, (B) is a (A). (C) is a molding die for forming the flat member B obtained in (B) into a predetermined shape using a molding die. (D) is a schematic view of a molded article C molded by the molding die of (C). It is the elements on larger scale of the molded article C obtained by (D) of FIG. It is a table | surface which shows the case where the compounding ratio of shaping | molding conditions and a composition at the time of heating and pressurizing with a press die about the Example and reference example of this invention is changed. It is a table | surface which shows the case where the weight ratio of PP resin of a base material layer and PET resin and a fabric weight are changed about the Example of this invention. It is a table | surface which shows the performance of each Example and a reference example.

  Hereinafter, embodiments of the present invention will be described in detail based on the drawings. The following description of the preferred embodiments is merely exemplary in nature.

(Embodiment 1)
Embodiment 1 of the present invention will be described based on the drawings. FIG. 1 relates to a first embodiment showing an example in which a vehicle exterior soundproofing material according to the present invention is applied to a fender liner, and is a side view of an essential part showing a front part of a vehicle attached with this fender liner. FIG. 2 is an enlarged cross-sectional view taken along the line II-II in FIG. 1 and shows the fender liner and its peripheral portion. FIG. 3 is a manufacturing apparatus for forming a sheet material A having a three-layer structure by laminating reinforcing layers on both sides of a base material layer in the manufacturing process of the vehicle exterior soundproofing material of Embodiment 1 used for the fender liner of FIG. Is a figure which shows typically. FIG. 4 is a partial enlarged cross-sectional view of the sheet material A having a three-layer structure obtained in FIG. 3, and the thickness of each layer is shown exaggerating the actual thickness. FIG. 5 is a view showing the manufacturing process of the vehicle exterior soundproofing material of the first embodiment. FIG. 6 is a partially enlarged cross-sectional view of the molded article C obtained in FIG. 5, and the thickness of each layer is shown exaggerating the actual thickness.

  In the vehicle 1, tires 2 are usually disposed on the left and right of the front and the left and right of the rear, and wheel houses 3 are disposed above the tires 2 respectively. The wheel house 3 is also called a wheel house panel or a wheel housing, and constitutes a part of a vehicle body. The wheel house 3 is made of metal and is shaped to cover the upper side of the tire 2. The surface on the tire 2 side of the wheel house 3 is the outer surface of the vehicle, and the fender liner 10 is attached to the wheel house 3 so as to cover the outer surface. The fender liner 10 prevents the pody panel from being damaged by pebbles, muddy water, etc. that the tire 2 bounces off the road surface while the vehicle 1 is traveling, and reduces noise such as road noise generated by the tire 2 and the road surface. The exterior soundproofing material of the vehicle 1 is used.

  Recently, there is also known one in which the wheel house 3 is omitted and the fender liner 10 serves as a partition between the vehicle interior such as the engine room and the tire side. Although the first embodiment is described as an example in which the fender liner 10 is provided on the outside of the wheel house 3, the present invention is also applicable to the case where the wheel house 3 is omitted.

  As shown in FIGS. 1 and 2, the fender liner 10 is formed in a shape along the wheel house 3 and attached to the wheel house 3 by a fastener or the like (not shown).

  Next, an outline of the fender liner 10 of the first embodiment will be described. As shown in FIG. 2, the fender liner 10 is shaped to conform to the wheel house 3.

  As shown in FIG. 6, the molded article C, which is the fender liner 10, includes the base material layer 11 disposed in the middle, and the reinforcing layer (first reinforcing layer) 14 disposed on the tire 2 side of the base material layer 11. The reinforcing layer (second reinforcing layer) 16 disposed on the wheel house 3 side of the base layer 11 is integrally provided. Reinforcing films 15 and 17 are formed on the outer surfaces of the first reinforcing layer 14 and the second reinforcing layer 16, respectively. As shown in FIG. 2, a gap t is provided between the second reinforcing layer 16 and the wheel house 3.

  As shown in FIG. 4, the base material layer 11 has a substantially mesh shape in which a first fiber 12 made of PP resin and a binder fiber (second fiber) 13 made of a synthetic fiber to be heated and fused are entangled and fused It is configured to have a structure. The binder fiber 13 has a core-sheath structure made of polyethylene terephthalate resin (hereinafter referred to as PET resin), and the PET resin in the sheath portion is melted to melt the core portion of the binder fiber 13 and the first fibers 12. Wear it. That is, since the binder fiber 13 is configured to be fusion cured in a state in which the first fibers 12 are entangled, the fender liner 10 (the molded product C) is easily and reliably formed into a three-dimensional three-dimensional shape. In addition to being able to do this, it is possible to hold its shape reliably. Furthermore, since the binder fiber 13 is present while retaining the fiber shape as an interlacing fiber that constitutes the base material layer 11 together with the first fiber 12, more minute cells are formed inside the base material layer 11. It helps a lot. As a result, it is possible to easily form a structure (substantially network-like structure) configured to be able to enhance the sound absorption performance of the base material layer 11. In particular, the base material layer 11 exists as an aggregate of minute cells as a space surrounded by a plurality of fibers, and the sound absorption effect is mainly exhibited by the cells.

  In the base material layer 11, PP resin which is the first fiber 12 is required to be 20% by weight or more in order to improve heat resistance, but if it is too much, impact resistance and rigidity become weak and tear strength decreases. It is preferable to set it as 40 weight% or less. In addition, PET resin (second fiber) 13 which is a binder fiber needs 60% or more in order to secure board thickness and improve sound absorption and maintain tear strength and molding shape, and if it is too much, it is relatively Since the amount of the PP resin decreases and the heat resistance decreases, it is preferable to set it to 80% or less. That is, it is preferable to contain 20 to 40% by weight of PP resin, and 80 to 60% by weight of PET resin (second fiber) 13 as a binder fiber.

The weight per unit area of the base material layer 11 needs to be 400 g / m ² or more in order to secure sound absorption and shape retention of a three-dimensional shape, and when it is too high, the weight increases, and therefore 800 g / m ² or less. Is preferred. Further, in order to prevent the first reinforcement layer 14 and the second reinforcement layer 16 from invading too much, it is preferable to set it to 400 g / m ² or more. In ^particular, it is preferable to ^{500g / m 2 ~700g / m 2} .

  The fiber diameter of the first fiber 12 is preferably 4T (dtex: dtex) to 20T, particularly 6T to 17T, in order to enhance the processing stability in the manufacturing process of the fender liner 10 (the molded product C). If the fiber diameter of the first fiber 12 is less than 4 T, the strength may be reduced. On the other hand, if it exceeds 20 T, the proportion of the volume of the first fiber 12 occupying the entire base layer 11 is extremely easily increased, so that it is not possible to form a large number of cells.

  The fiber length of the first fiber 12 is preferably a short fiber in the range of 10 mm to 100 mm in order to enhance processing stability in the manufacturing process of the fender liner 10. Furthermore, since it is possible to form more minute cells, it is preferable to be configured to have mechanical crimp and the like.

  The binder fiber 13 is a main fiber constituting the base layer 11 together with the first fiber 12, and is constituted by a soluble polymer alone having a melting point lower than that of the first fiber 12 or a core-sheath structure having a soluble polymer as a sheath. Is preferred. As this binder fiber 13, since a large number of cells can be easily formed inside the base layer 11, a synthetic fiber consisting of a soluble polymer simple substance that can be easily formed thinner than a composite fiber is suitably used. In particular, low melting point PET fibers having a melting point of 100 ° C. to 130 ° C. are most preferably used because they have good moldability and are easily available and inexpensive. In particular, the sheath portion is a low melting point PET fiber having a melting point of 100 ° C. to 130 ° C., and the core portion does not have to have a melting point lower than that of the first fiber 12. It is preferable to have the above melting point, and it is preferable to use a high melting point PET fiber having a melting point of around 250 ° C. Furthermore, this PET fiber also has the advantage of being excellent in recyclability.

  The fiber diameter of the binder fiber 13 is preferably 4T to 20T, and more preferably 6T to 17T, in order to enhance the processing stability in the manufacturing process of the fender liner 10 (the molded article C). If the fiber diameter of the binder fiber 13 is less than 4 T, the strength may be reduced. In addition, there is a possibility that the shape as a fiber can not be retained by melting at the time of press molding, and it can not contribute to the formation of a cell. On the other hand, if it exceeds 20 T, the ratio of the volume of the binder fiber 13 occupying in the entire base layer 11 can be extremely easily increased, so that many cells can not be formed.

  Moreover, as a fiber length of this binder fiber 13, in order to improve the process stability in the manufacturing process of the fender liner 10, it is preferable that it is a short fiber of the range of 10 mm-100 mm. Furthermore, since it is possible to form more minute cells, it is preferable to be configured to have mechanical crimp and the like.

  The first reinforcing layer 14 and the second reinforcing layer 16 allow the fender liner 10 to be easily formed into a three-dimensional shape and to be excellent in deformation resistance after forming and to have high sound absorption performance for the fender liner 10 (formed product C) And excellent anti-icing properties. Then, the first reinforcing layer 14 absorbs the road noise at the time of traveling and repellents the rain water and mud water scattered from the road surface by the tire 2 to prevent the outer surface of the fender liner 10 from being soiled. And prevent water absorption and icing. The second reinforcing layer 16 is required to improve the sound absorption performance as well as not to absorb the existing water due to the fact that the fender liner 10 wraps around to the wheel house side (the opposite side to the road surface side), etc. It is required. Therefore, the second reinforcing layer 16 also prevents moisture from being absorbed into the fender liner 10 by preventing moisture from being absorbed, thereby preventing the water, such as rain water and mud water, from flowing around the back side of the fender liner 10 from entering the fender liner 10. Can be prevented. At the same time, it is possible to absorb road noise during traveling and to be excellent in formability. Reinforcing films 15 and 17 are formed on the outside of the first and second reinforcing layers 14 and 16, respectively.

  If the first reinforcing layer 14 and the second reinforcing layer 16, and the reinforcing film 15 and the reinforcing film 17 are non-air-permeable film layers, both sides of the substrate layer 11 will be covered with the non-air-permeable layer. The sound absorption by the membrane vibration results in the deterioration of the sound absorption in the high frequency region. On the other hand, in the present embodiment, both the first reinforcing layer 14 and the second reinforcing layer 16 adopt PP resin and PET resin to make the same material as the base material layer 11 and breathable, and the first reinforcing layer 14 · By forming the air-permeable reinforcing film 15 · reinforcing film 17 from the first reinforcing layer 14 · second reinforcing layer 16 on the outside of the second reinforcing layer 16, the deterioration of the sound absorption is prevented Not only that, but the air flow resistance value is increased, and the sound absorption performance is improved in almost the entire area. Both are made of PP resin and PET resin, and by sandwiching the base material layer 11 in which the ratio of PP resin and PET resin is different between the first reinforcing layer 14 and the second reinforcing layer 16 in the same ratio of PP resin and PET resin. Because it is sandwiched by the same material, it is difficult to warp, and a three-phase structure with stable density can be obtained in any part, so it exerts the sound absorption effect by the synergetic effect of three phases as well as the low to middle sound region by membrane vibration. The sound absorption in the high frequency range is expected to be improved.

  The first reinforcing layer 14 is configured to have a substantially network structure in which a first fiber 18 made of a PP resin and a second fiber 19 made of a synthetic fiber to be heated and fused are entangled and fused. . The second fiber 19 has a core-sheath structure of a PET resin, and the PET resin in the sheath portion melts and fuses in a state in which the core portion of the second fiber 19 and the first fibers 18 are entangled.

  In the reinforcing layers 14 and 16, the PP resin which is the first fiber 18 is required to be 60% by weight or more in order to maintain the heat resistance, and if it is too much, it becomes a film, the sound absorption deteriorates and the tearing strength decreases. And 90% by weight or less. Also, in order to form a reinforcing film on the outer surface and enhance chipping resistance and icing releasability, the above-mentioned 60 wt% or more is necessary. In addition, PET resin is required to maintain its forming shape and 10% by weight or more in order to secure bending rigidity, and if it is too much, relatively less PP resin will be contained. Since it can not be formed and the rigidity tends to be insufficient, the content is preferably 40% by weight or less. That is, it is preferable to contain 60 to 90% by weight of the PP resin which is the first fiber 18 and 40 to 10% by weight of the PET resin (second fiber) 19 which is the binder fiber.

  The first reinforcing layer 14 and the second reinforcing layer 16 are the same reinforcing layer, and in the following description, the first reinforcing layer 14 will be described, but the same can be said for the second reinforcing layer 16. The description of the reinforcing layer 16 is omitted.

The basis weight of the first reinforcing layer ^{14, 100g / m 2 ~300g /} m 2, preferably from ^{150g / m 2 ~200g / m 2} . If it is less than 100 g / m ² , the layer of the first reinforcing layer 14 will be insufficient, and a partial thin portion may be formed, and in some cases, there is a high possibility that a portion without the breathable reinforcing membrane 15 may be present. On the other hand, if it exceeds 300 g / m ² , the sound absorption effect is likely to be impaired.

  The fiber diameter of the first fiber 18 is preferably 2T (dtex: dtex) to 10T, particularly 4T to 8T, in order to enhance processing stability in the manufacturing process of the fender liner 10. If the fiber diameter of the first fiber 18 is less than 2T, the strength may be reduced. Conversely, if it exceeds 10 T, the proportion of the volume of the first fiber 12 in the entire first reinforcing layer 14 is extremely easily increased, and it is not possible to form a large number of cells.

  The fiber length of the first fiber 18 is preferably a short fiber in the range of 10 mm to 100 mm in order to enhance the processing stability in the manufacturing process of the fender liner 10. Furthermore, since it is possible to form more minute cells, it is preferable to be configured to have mechanical crimp and the like.

  The second fiber 19 is a main fiber constituting the first reinforcing layer 14 together with the first fiber 18, and a soluble polymer alone having a melting point lower than that of the first fiber 18, or a core sheath having a soluble polymer as a sheath part It is preferable that it is comprised by the structure. As this second fiber 19, a synthetic fiber made of a soluble polymer simple substance that can be easily formed thinner than a composite fiber is preferable because a large number of cells can be easily formed inside the first reinforcing layer 14. In particular, PET fibers having a melting point of 100 ° C. to 130 ° C. for the sheath portion are most preferably used because they have good moldability and are easily available and inexpensive. In particular, when the melting point of the sheath portion is too high, the fluidity is insufficient when heating and press-molding, and the first reinforcing layer 14 can not follow the forming direction of the base layer 11, and the formability is deteriorated. On the contrary, if the melting point is too low, it may melt too much and penetrate into the base material layer 11 to increase the possibility of the formation of large holes in the first reinforcing layer 14, so a melting point of 100 ° C. to 130 ° C. may be obtained. preferable. The core portion need not have a melting point lower than that of the first fiber 18, but rather preferably has a melting point equal to or higher than that of the first fiber 18, and has a melting point of 180 ° C to 250 ° C. It is preferable to set it as PET fiber of melting | fusing point. Furthermore, this PET fiber also has the advantage of being excellent in recyclability.

  The fiber diameter of the second fiber 19 is preferably 2T to 10T, particularly 4T to 8T, in order to enhance the processing stability in the manufacturing process of the fender liner 10. If the fiber diameter of the second fiber 19 is less than 2T, the strength may be reduced. In addition, there is a possibility that the shape as a fiber can not be retained by melting at the time of press molding, and it can not contribute to the formation of a cell. On the other hand, if it exceeds 10 T, even if the second fiber 19 melts at the time of press molding, there is a possibility that the melt portion and the melt portion will not be continuously connected, resulting in no reinforcement film. Therefore, it is preferable to set it as the said range.

  The fiber length of the second fiber 19 is preferably a short fiber in the range of 10 mm to 100 mm in order to enhance the processing stability in the manufacturing process of the fender liner 10. Furthermore, since it is possible to form more minute cells, it is preferable to be configured to have mechanical crimp and the like.

The basis weight of the second reinforcing layer ^{19, 100g / m 2 ~300g /} m 2, preferably from ^{150g / m 2 ~200g / m 2} . If it is less than 100 g / m ² , the layer of the first reinforcing layer 14 will be insufficient, and a partial thin portion may be formed, and in some cases, there is a high possibility that a portion without the breathable reinforcing membrane 15 may be present. On the other hand, if it exceeds 250 g / m ² , the sound absorption effect is likely to be impaired.

  The manufacturing method of the sheet | seat material A of the exterior soundproof material for vehicles is demonstrated based on FIG.3 and FIG.4. First, the base nonwoven fabric A1 and the reinforcing nonwoven fabrics A2 and A2 are prepared. The base nonwoven fabric A1 forms a dry nonwoven fabric for the base sheet into a sheet shape using the first fibers 12 and the second fibers 13, and then the fibers 12, 13 in the nonwoven fabric are needle punched (not shown) ) And entangle each other according to. The reinforcing nonwoven fabrics A2 and A2 are also produced in the same manner as the substrate nonwoven fabric A1. That is, after both of the reinforcing nonwoven fabrics A2 and A2 form the dry nonwoven fabric for the reinforcing sheet into a sheet using the first fibers 18 and the second fibers 19, the fibers 18 and 19 in the nonwoven fabrics can be They are entangled and entangled with each other by a needle punch (not shown) to produce reinforcing nonwoven fabrics A2 and A2.

  Next, as shown in FIG. 3, the reinforcing nonwoven fabric A2, the base nonwoven fabric A1, and the reinforcing nonwoven fabric A2 are carried to the manufacturing apparatus 30. In the manufacturing apparatus 30, the base nonwoven fabric A1 is conveyed between the rollers 32a and 32a by the rollers 31a and 31a. The reinforcing non-woven fabrics A2 and A2 are respectively conveyed between the rollers 32a and 32a by the rollers 31b. The reinforcing non-woven fabric A2, the base non-woven fabric A1, and the reinforcing non-woven fabric A2 are stacked in three layers between the rollers 32a and 32a, entangled and entangled with each other by a needle punch (not shown). Material A (see FIG. 4) is produced. As a result, a sheet material A having a three-layer structure as shown in FIG. 4 is generated.

  Next, the sheet material A of the three-layer structure obtained in FIG. 4 is placed on a press die 50, as shown in FIG. 5 (A). The press die 50 includes an upper die 51 and a lower die 52. The upper mold 51 and the lower mold 52 both have the heating coils 53 and 54 inside, and the mold surfaces in contact with the outer surfaces of both reinforcing non-woven sheets of the sheet material A are, for example, flat plate heated to 200 ° C. It consists of a heat plate 55,55. As shown in FIG. 5B, the upper die 51 of the flat press die is lowered and pressurized to, for example, a die clearance of 5.1 mm, and held for 30 seconds, for example. The sheet material A is held in a heated and pressurized state by the press die 50 to integrate the sheet material A and to reinforce the outer surfaces A21 of the reinforcing non-woven fabrics A2 in contact with the heat plates 55, 55 respectively. , 17 are produced to produce a flat plate-like member B.

  Then, while the flat plate member B is in a preheating state by heating by the heat plates 55, 55, the flat plate member B is cooled while being pressurized by the cooling forming die 70, as shown in FIG. The reinforcement films 15 and 17 are left on the outer surface of the reinforcement layers 14 and 16 to form a molded article C having a predetermined three-dimensional shape. As a result, as shown in FIG. 5D, a three-dimensionally shaped molded article C is obtained. An enlarged cross-sectional view of this molded article C is shown in FIG. The first reinforcing layer 14 and the second reinforcing layer 16 are integrally laminated on both sides of the base material layer 11 with the reinforcing films 15 and 17 remaining on the outer surfaces of both the reinforcing layers 14 and 16, respectively. Reinforcing films 15 and 17 remain on the outer surfaces of the 14 and the second reinforcing layer 16.

  The details of the molding process will be described below. In the press molding process, since the lower mold 52 and the upper mold 51 are heated at 200 ° C., the first reinforcing layer 14 and the second reinforcing layer 16 are heated and the base layer 11 is also heated. At this time, this heating temperature is performed at a temperature equal to or higher than the melting point of the soluble polymer alone constituting the binder fibers 13 and 18. The melting points of the binder fiber 13 of the base layer 11 and the second fibers 19 of the reinforcing layers 14 and 17 are the same as the first fibers of the first fiber 12, the first reinforcing layer 14 and the second reinforcing layer 16 of the base layer 11. Since the melting point is lower than the melting point of 18, the binder fibers 13 and 19 are melted and the flowability is high at the time of heating, and both are closely adhered. And all of the melted first reinforcing layer 14 and second reinforcing layer 16 do not penetrate into the base layer 11, leaving the first reinforcing layer 14 and the second reinforcing layer 16; 2) The cell size and basis weight of the base material layer 11 are set so that the reinforcement films 15 and 17 are obtained on the outside of the reinforcement layer 16, and the clearance of the heating press die (that is, the pressing thickness) Pressure temperature and pressure time are also set.

  In addition, when heating and pressurizing by sandwiching the heat plates 55, 55, the heating temperature of the sheet is 180 to 240 ° C., the thickness after pressurization / the thickness before pressurization is 0.87 to 0.960.85 to It is preferable to pressurize to a ratio of 0.90 and to heat the press time for 20 to 60 seconds.

  If the heating temperature is too low with respect to these ranges, the flowability of the first reinforcing layer 14 and the second reinforcing layer 16 will be insufficient and it will be easy to peel off from the base material layer 11. Many binder fibers 19 may be dissolved in the direction of the first reinforcing layer 14 and the second reinforcing layer 16, and the first reinforcing layer 14 and the second reinforcing layer 16 may easily permeate into the base layer 11. If the time is too short, the flowability of the first reinforcing layer 14 and the second reinforcing layer 16 will be insufficient, and the reinforcing membranes 15 and 17 will not be generated easily. There is not much change even if the time is extended, but it is better not to make it so long in terms of productivity and cost. If the mold clearance is too wide, the formation of the reinforcing film of the first reinforcing layer 14 and the second reinforcing layer 16 and the substrate 11 is insufficient, and if it is too narrow, the substrate layer 11 is compressed too much and the vents on the surface are There is a high possibility that the sound absorption property is deteriorated due to crushing, and the air flow resistance of the reinforcing layers 14 and 17 also tends to be high. Therefore, it is preferable to use the above numerical values.

  In addition, since the boundary part of the base material layer 11 and the 1st reinforcement layer 14 and the 2nd reinforcement layer 16 can not be distinguished clearly after shaping | molding, the thickness after shaping | molding is the base material layer 11 and the 1st reinforcement layer 14 It is difficult to explain as the second reinforcing layer 16. Therefore, the thickness after shaping | molding demonstrates the preferable range with the thickness as a vehicle exterior soundproofing material, and the thickness of reinforcement film 15,17.

  The thickness (after molding) of the vehicle exterior soundproofing material is preferably 2 mm to 7 mm, more preferably 3 mm to 5 mm. When the thickness of the vehicle exterior soundproofing material is less than 2 mm, sufficient rigidity retention and shape retention of the fender liner 10 can not be obtained. In addition, a large number of cells can not be formed, and a sufficient sound absorption effect can not be exhibited. On the other hand, if it exceeds 7 mm, the weight reduction of the fender liner 10 can not be achieved and the cost increases.

  The thickness of the reinforcing films 15 and 17 is preferably 100 μm to 300 μm, and more preferably 150 μm to 250 μm. In the case of less than 100 μm, the reinforcing membranes 15 and 17 are very likely to be broken. Conversely, if it exceeds 300 μm, high film vibration absorption can not be induced, and the sound absorption effect of the road noise may be impaired. Therefore, it is preferable to set it as the said range.

  In particular, the PET resin of the base material layer 11, the first reinforcing layer 14 and the second reinforcing layer 16 is fluidized or partially melted to form a base material by appropriately setting and forming heating conditions and pressure conditions. While it will soak into the side and is firmly adhered to the base material layer 11 and the temperature of the outside of the first reinforcing layer 14 and the second reinforcing layer 16 becomes the highest temperature, this part of the PET resin melts well The pressure is applied to form a film as the reinforcing layers 15 and 17.

  The effects exerted by the present embodiment will be described below.

  The fender liner 10 is configured such that rainwater and muddy water are less likely to infiltrate into the base material layer 11 by the reinforcement film 15 of the first reinforcement layer 14 and the reinforcement film 17 of the second reinforcement layer 16. Even if rain water or muddy water that tire 2 scatters is designed to be water repellent even if it comes in contact with fender liner 10, it is effective to prevent icing and to make the outer surface of fender liner 10 dirty by dirt and dust etc. Suppressed. Furthermore, since the reinforcing film 15 of the first reinforcing layer 14 and the reinforcing film 17 of the second reinforcing layer 16 are formed as the air-permeable reinforcing film, the sound absorbing action is not hindered.

  At the same time, the properties such as tensile strength, flexural strength, elastic gradient, etc. of the fender liner 10 are improved by the first reinforcing layer 14 and the second reinforcing layer 16 and the reinforcing films 15 and 17, so that the shape retention after molding is excellent. . Therefore, even when the fender liner 10 is provided with a passage for air such as cooling air, the fender liner 10 has excellent shape maintenance, which can be coped with. In addition, when the improvement of the characteristics is not required, the weight of the base layer 11 can be reduced.

  In the above embodiment, the sheet material of the three-layer structure in which the reinforcing non-woven fabric is laminated on both sides of the non-woven fabric for the base material is prepared in advance by needle punching or the like. Alternatively, the reinforcing non-woven fabric, the base non-woven fabric, and the reinforcing non-woven fabric may be stacked with a press die and integrated with this press die.

  Examples of the present invention will be specifically described below. EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited by the examples.

Example 1
As the first fibers 12 of the base layer 11, fibers of PP resin having a fiber diameter of 6 T, a fiber length of 64 mm, and a melting point of 180 ° C. were used. The binder fiber 13 has a core-sheath structure in which a PET fiber having a fiber diameter of 17 T, a fiber length of 64 mm, and a melting point of 110 ° C. is used as a sheath and a fiber diameter of 17 T and a fiber length of 64 mm is obtained. 30% by weight of PP resin and 70% by weight of PET resin.

  As the first fibers 18 of the first reinforcing layer 14 and the second reinforcing layer 16, PP fibers having a fiber diameter of 6 T, a fiber length of 64 mm, and a melting point of 180 ° C. were used. The binder fiber 19 has a core-sheath structure in which a PET fiber having a fiber diameter of 6T, a fiber length of 64 mm, and a melting point of 110 ° C. is used as a sheath, and a fiber diameter of 6T and a fiber length of 51 mm and a melting point of 250 ° C. is used as a core. 70% by weight of PP resin and 30% by weight of PET resin.

The PP resin 12 and the PET resin 13 of the base material layer 11 were mixed such that the content of the PP resin was 30% by weight and that of the PET resin was 70% by weight, and they were entangled by needling to produce a nonwoven fabric for base A1. The weight per unit area of the base nonwoven fabric A1 was 700 g / m ² . The PP resin 18 and the PET resin 19 of the first reinforcing layer 14 and the second reinforcing layer 16 are mixed so that 70% by weight of the PP resin and 30% by weight of the PET resin are mixed and entangled by needling to reinforce nonwoven fabric A2 and A2 were produced. The weight per unit area of the reinforcing nonwoven fabrics A2 and A2 was 200 g / m ² . The base material non-woven fabric A1 and the reinforcing non-woven fabrics A2 and A2 are stacked to form, for example, a sheet material A having a three-layer structure joined by needle punching or the like. The thickness of the sheet material A is 5.5 mm.

  The sheet material A is placed on a flat press die. This press mold is a mold in which the heat plates 55, 55 are heated to 200.degree. The pressure is applied so that the mold clearance of the press mold is 4.8 mm, and the film is held for 30 seconds (seconds), and the reinforcing film 15 is formed on the outer surface A21 of both reinforcing non-woven fabrics A2 in contact with the heat plates 55,55. , 17 are produced to produce a flat plate-like member B.

The flat member B thus obtained is molded into a fender liner shape by the molding die of the fender liner 10. Specifically, while preheating when this flat member B is heated by a flat press die remains, it is pressurized by a molding die which is a cold die (cooling die) and a molded article is obtained. It is molded into a predetermined shape. In the fender liner 10 (molded product C) obtained after molding, the base material layer has a thickness of 4.0 mm and a basis weight of 1,100 g / m ² , and the reinforcement of the first reinforcing layer 14 and the second reinforcing layer 16 The thickness of the films 15, 17 was 250 μm.

  The thicknesses of the base material layer 11, the first reinforcing layer 14, the second reinforcing layer 16, and the reinforcing layers 15 and 17 are not constant, and thus the average thickness is taken as the whole, but the average thickness of most You may Although it is difficult to specifically compare the thickness of the first reinforcing layer 14 and the thickness of the second reinforcing layer 16 immediately before and after pressing with the mold, heating with the clearance of the mold and the press die It is predicted to be 0.96 times to 0.87 times, as predicted from the total thickness of the thicknesses of the front substrate non-woven fabric A1 and the reinforcing non-woven fabrics A2 and A2.

(Examples 2 to 6)
Examples 2 to 6 differ from Example 1 in that the heating time is 10 seconds, 20 seconds, 40 seconds, 50 seconds, and 60 seconds, and the others are the same as Example 1.

(Reference Example 1)
The first embodiment is based on the first embodiment and the heating time is substantially zero seconds.

(Examples 7 to 9)
In Examples 7 to 9, the heating temperature of the heat plate 55 of the press die is 160 ° C., 180 ° C., 220 ° C., and 240 ° C. based on Example 1, and the others are the same as Example 1. is there.

(Examples 10 to 12)
In Examples 10 to 12, based on Example 1, the mold clearance of the press mold and the mold clearance of the mold are 4.5 mm and 4.0 mm, 5.0 mm and 4.0 mm, 5.3 mm and 4 mm. The other dimensions are the same as in Example 3.

(Reference Example 2)
Reference Example 2 is based on Example 1, in which the mold clearance of the press mold and the mold clearance of the mold are 5.5 mm and 5.5 mm, that is, those which are not pressed and thinned .

(Reference Example 3)
In Reference Example 3, based on Example 1, the heating temperature of the press die is 160 ° C.

(Examples 13 to 16)
Examples 13-14 are the examples which changed the ratio of each fiber of the nonwoven fabric for base materials and the nonwoven fabric for reinforcement on the basis of Example 1. FIG. The fifteenth and sixteenth embodiments are examples in which the basis weight is changed based on the first embodiment. The molding method is the same as in Example 1.

  Comparative data of flexural rigidity, tensile strength, tear strength, durability, and air flow resistance of Examples 1 to 16 and Reference Examples 1 and 2 are shown in FIG.

Various test methods (Test method of bending stiffness)
The flexural rigidity was measured in accordance with JIS K 7171 with the size of sample S: 50 mm × 150 mm, span: 100 mm, test speed: 50 mm / min. The results of the flexural rigidity test are shown in FIG. As shown in FIG. 9, in the reference examples 1 and 2, 15N and 15N, and in the reference example 3, 17N, and in the examples 1 to 12, 17N or more. In this case, Reference Example 3 shows the same tensile strength value as that of the embodiment of the present invention, but the other performance could not satisfy the requirement.

(Test method of tensile strength)
The tensile strength was measured in accordance with JIS K 7161. The results are shown in FIG. In Examples 1 to 13 of the present invention, the tensile strength was 310 N to 370 N, and in Reference Examples 1 and 2, the tensile strength was 300 N. In Reference Example 3, the tensile strength was 320 N, which is a superior value to Example 12 of the present invention, but the other performance could not satisfy the requirement.

(Test method of tear strength)
The test method of tear strength was measured in accordance with JIS K 7128. The results are shown in FIG. In Examples 1 to 12, the tear strength was 206 N or less, and in Reference Examples 1, 2 and 3, it was 270 N, 270 N, and 260 N.

(Test method of icing peel strength test)
About this test method, since it carried out by the test method currently disclosed by Unexamined-Japanese-Patent No. 2011-240821, detailed description is abbreviate | omitted.

  The icing test shows the results in FIG. In Examples 1 to 12 of the present invention, the icing peel strength was 20 N to 45 N, and in Reference Examples 1, 2, 3 50 N.

(Test method of durability)
As a test of durability, 3 kg of pebbles with an average length of 3 mm to 7 mm in length, width and depth of cube pebbles were dropped from 2 m in height, and changes in the surface were observed and dropped 50 times. The subsequent surface condition and the amount of surface depression were measured. The results are shown in FIG.

  As shown in FIG. 9, in Examples 1 to 12, the amount of depression was 0.8 mm or less, but in each of Reference Examples 1, 2, and 3, the amount of depression was 1.0 mm, and the amount of depression was large.

(How to measure air flow resistance)
Each sample S is obtained in a size of 300 mm × 300 mm. The weight of this sample is measured in the usual manner. A specific measurement method is disclosed in Japanese Patent Application Laid-Open No. 2014-000897, and thus will not be described here. In Examples 1, 4 to 11, it was 250 or more, and in Reference Examples 1, 2, 3, it was 100, 100, and 200, respectively, and the air resistance was low and the sound absorption was inferior.

(Reverberation chamber method sound absorption coefficient)
Although the test method of the sound absorption test measures the reverberation chamber method sound absorption coefficient based on ISO354 in the frequency range of 200 to 6300 Hz using a measurement apparatus manufactured by Breuer CARE, the sound absorption coefficient of Examples 1 to 12 is The experiment was omitted because it can be expected to show a relatively large sound absorption coefficient in the frequency range of 800 to 2000 Hz.

  The present invention can be advantageously applied to vehicle exterior soundproofing materials such as fender liners, mudguards, undercovers and the like.

A Sheet material A1 Non-woven fabric for base material A2 Non-woven fabric for reinforcement B Flat plate member C Molded article 10 Fender liner 11 Base material layer 12 First fiber 13 Second fiber 14 Reinforcement layer 15 Reinforcement film 16 Reinforcement layer 17 Reinforcement film 18 Reinforcement film 18 First fiber 19 second fiber 50 press mold 70 cooling mold

Claims (9)

A method of manufacturing an exterior soundproofing material for a vehicle, comprising: a base material layer having a sound absorbing action; and reinforcing layers integrally provided on both sides of the base material layer,
The material of the base layer is a sheet-like base nonwoven fabric in which a first fiber made of polypropylene resin fiber and a second fiber made of binder fiber having a melting point lower than that of the polypropylene resin are entangled.
The material of the two reinforcing layers is made of the same sheet-like reinforcing non-woven fabric in which first fibers made of polypropylene resin fibers and second fibers made of binder fibers having a melting point lower than that of the polypropylene resin are entangled. ,
The nonwoven fabric for the base material has a high basis weight as compared to each reinforcing nonwoven fabric,
The non-woven fabric for a substrate is a non-woven fabric containing a smaller amount of the first fibers and a larger amount of the second fibers as compared to the reinforcing non-woven fabrics,
Producing a sheet material of a three-layer structure in which the reinforcing non-woven fabric is laminated on both sides of the base non-woven fabric,
The sheet material is heated and pressed with a press die consisting of a heated flat plate-shaped heat plate, and the reinforcing sheet in contact with the heat plate. Producing a flat plate-like member formed by respectively forming a reinforcing film on the outer surface of the non-woven fabric,
While being heated by the heat plate, the flat plate member is cooled while being pressurized by a cooling mold, and a molded article of a predetermined three-dimensional shape is left while leaving the reinforcing film on the outer surface of both reinforcing layers. The manufacturing method of the exterior soundproofing material for vehicles characterized by shape | molding to. In claim 1,
While the heating state by heating of the heat plate remains, and while the flat member can be formed into a three-dimensional shape, the flat member is cooled while being pressurized with a cooling mold, and both reinforcing layers are formed. A method of manufacturing an exterior soundproofing material for a vehicle, comprising forming the molded article into a predetermined three-dimensional shape while leaving the reinforcing film on the outer surface of the molded article. In claim 1 or 2,
A method of manufacturing an exterior soundproofing material for a vehicle, wherein the heat plate is heated by a heater. In any one of claims 1 to 3,
A method of manufacturing an exterior soundproofing material for a vehicle, wherein the cooling mold is cooled by a cooling water. In any one of claims 1 to 4,
A method of producing an exterior soundproofing material for a vehicle, wherein the binder fiber is a PET resin. In any one of claims 1 to 5,
The non-woven fabric for a substrate has a basis weight of 400 to 800 g / m ² , and the first fiber is 20 to 40% by weight, and the second fiber is 80 to 60% by weight.
Each reinforcing nonwoven fabric has a basis weight of 100 to 300 g / m ² , and the first fiber is 60 to 90% by weight, and the second fiber is 40 to 10% by weight. How to make a soundproofing material. In any one of claims 1 to 6,
The heating temperature of the heating plate is 180 to 240 ° C., and the thickness of the sheet material after pressing / the thickness before pressing when the sheet material is sandwiched between the heating plate of the press mold and heated and pressed. The manufacturing method of the exterior soundproofing material for vehicles characterized by pressurizing to thickness ratio of = 0.9-0.85 times, and pressurizing time being 20 to 60 seconds. In any one of claims 1 to 7,
The thickness of the said vehicle exterior soundproofing material is 3.5-5.0 mm, The thickness of this reinforcement film is 150-300 micrometers, The manufacturing method of the vehicle exterior soundproofing material characterized by the above-mentioned. In any one of claims 1 to 8,
The method for producing an exterior soundproofing material for a vehicle, wherein the binder fiber has a core-sheath structure, the core portion is a high melting point PET resin, and the sheath portion is a low melting point PET resin.

Images