JP6629809B2 - Laminated glass mounting structure - Google Patents

Description

  The present invention relates to a laminated glass mounting structure used for a windshield of an automobile and the like.

  In recent years, from the viewpoint of improving fuel efficiency of automobiles, it is required to reduce the weight of glass such as a windshield to be mounted, and accordingly, development of glass having a small thickness has been promoted. However, when the thickness is reduced, the sound insulation performance is reduced, so that sound outside the vehicle flows into the vehicle, and there is a problem that the environment inside the vehicle is deteriorated. In order to solve this, for example, Patent Literature 1 describes a laminated glass for an automobile that maintains sound insulation performance at a predetermined frequency while reducing the areal density. This laminated glass has a resin intermediate film disposed between a pair of glass plates.

JP 2002-326847 A

  By the way, in the laminated glass as disclosed in Patent Document 1, a reduction in sound insulation performance can be prevented to some extent by reducing the thickness. Is more likely to occur. In order to solve this problem, a method is considered in which only the glass plate on the inside of the vehicle is made thinner while the thickness of the glass on the outside of the vehicle is made equal to the conventional one, thereby reducing the surface density as a whole. With respect to this point, the present inventors have studied as follows.

  First, when the thickness of the glass on the inside and the outside of the vehicle are different from each other, the present inventors have a frequency range of 2000 to 5000 Hz that is easier for humans to hear as compared to the case of the same thickness as shown in FIG. It has been found that the sound insulation performance is reduced. FIG. 3 is a graph showing the result of simulating the relationship between frequency and sound transmission loss (STL). In this graph, a laminated glass constituted by two glass plates having a thickness of 1.5 mm (hereinafter, referred to as a first laminated glass) and glass plates having different thicknesses of 2.0 mm and 1.0 mm were used. A laminated glass (hereinafter, referred to as a second laminated glass) is displayed. In each of the laminated glasses, a resin interlayer is disposed between two glass plates. According to this graph, it can be seen that the sound transmission loss of the second laminated glass is lower than that of the first laminated glass in the frequency range of 3000 to 5000 Hz. That is, it was found that the use of glass plates having different thicknesses deteriorates the sound insulation performance in the frequency range of 2000 to 5000 Hz that is easy for humans to hear.

  As described above, when glasses having different thicknesses are combined, a problem that the sound transmission loss is reduced occurs although the weight can be reduced. In particular, there is a problem that the sound insulation performance in a frequency range of 2000 to 5000 Hz that is easy for humans to hear is reduced, and the environment inside the vehicle is deteriorated. Such a problem is a problem that can occur not only in automobile glass but also in general for laminated glass that requires light weight and sound insulation.

  The present invention has been made in order to solve the above-mentioned problem, and an object of the present invention is to provide a laminated glass mounting structure that achieves both light weight and sound insulation.

  The mounting structure for a laminated glass according to the present invention includes a laminated glass, and a mounting portion capable of mounting the laminated glass such that a mounting angle from a vertical direction at a lower end of the laminated glass is 45 degrees or less, The laminated glass includes an outer glass plate, an inner glass plate arranged to face the outer glass plate, and an intermediate film sandwiched between the outer glass plate and the inner glass plate, and the thickness of the inner glass plate is reduced. 0.6 to 1.8 mm, the intermediate film is composed of a plurality of layers including at least a core layer, and the Young's modulus of the core layer is 1 to 20 MPa at a frequency of 100 Hz and a temperature of 20 ° C. , Lower than the Young's modulus of the other layers. Such a mounting structure is, for example, an automobile, a building, or the like, and the mounting portion is a frame on which a laminated glass is mounted. Further, the laminated glass can be attached to the attachment portion by a known method.

  The laminated glass according to the present invention includes an outer glass plate, an inner glass plate facing the outer glass plate, and an intermediate film sandwiched between the outer glass plate and the inner glass plate, and the inner glass plate. Is 0.6 to 1.8 mm, and the intermediate film is constituted by a plurality of layers including at least a core layer, and sets a straight line connecting the center of the upper side and the center of the lower side of the inner glass plate. When the core layer is curved so that the maximum distance between the straight line and the inner glass plate is larger than 30 mm, the Young's modulus of the core layer is 1 to 20 MPa at 100 Hz and 20 ° C. Lower than the Young's modulus of the layer.

  Further, the laminated glass according to the present invention is disposed between the outer glass plate, the outer glass plate, and the inner glass plate having a smaller thickness than the outer glass plate, and is sandwiched between the outer glass plate and the inner glass plate. And an intermediate film, wherein the thickness of the inner glass plate is 0.6 to 1.8 mm, the intermediate film is constituted by a plurality of layers including at least a core layer, and the Young's modulus of the core layer is , 100 Hz and 20 ° C., 1 to 20 MPa, which is lower than the Young's modulus of the other layers.

  In the laminated glass or the mounting structure described above, the thickness of the inner glass plate can be 0.8 to 1.6 mm.

  In the laminated glass or the mounting structure described above, the thickness of the inner glass plate can be 1.0 to 1.4 mm.

  In the laminated glass or the mounting structure described above, the thickness of the inner glass plate can be 0.8 to 1.3 mm.

  In the laminated glass or the mounting structure described above, the thickness of the core layer can be 0.1 to 2.0 mm.

  In the laminated glass or the mounting structure described above, the thickness of the outer glass plate can be 1.8 to 5.0 mm.

  In the laminated glass or the mounting structure described above, the Young's modulus of the core layer can be 1 to 16 MPa at a frequency of 100 Hz and a temperature of 20 ° C.

  In the laminated glass or the mounting structure described above, the tan δ of the intermediate film can be 0.5 to 3.0 at a frequency of 100 Hz and a temperature of 20 ° C.

  In the laminated glass or the mounting structure described above, the tan δ of the core layer can be 0.5 to 3.0 at a frequency of 100 Hz and a temperature of 20 ° C.

  In the above-mentioned laminated glass or mounting structure, the intermediate film has at least one outer layer in contact with the core layer, and at a frequency of 100 Hz and a temperature of 20 ° C., the tan δ of the outer layer is changed to the tan δ of the core layer. And smaller.

  In the laminated glass or the mounting structure described above, when a straight line connecting the center of the upper side and the center of the lower side of the inner glass plate is set, the maximum distance between the straight line and the inner glass plate is larger than 30 mm. The laminated glass may be curved.

  ADVANTAGE OF THE INVENTION According to this invention, the mounting structure of laminated glass which can achieve both weight reduction and sound insulation can be provided.

It is a sectional view showing one embodiment of a laminated glass concerning the present invention. It is the front view (a) and sectional view (b) which show the amount of doubling of curved laminated glass. It is a graph which shows the relationship between the general frequency and sound transmission loss of a curved glass plate and a planar glass plate. It is a schematic plan view which shows the measurement position of the thickness of a laminated glass. It is an example of an image used for measurement of a core layer. It is the schematic which shows the attachment method of a laminated glass. It is a graph which shows the relationship between the frequency and the sound transmission loss when the thickness of the veneer glass is changed. It is a graph which shows the result of evaluation of an outside glass plate. It is a model figure of the simulation for outputting a sound transmission loss. 4 is a graph showing a result of evaluation on a Young's modulus of a core layer. 4 is a graph showing the results of evaluation on the thickness of a core layer. It is a graph which shows the result of evaluation about the attachment angle of laminated glass. It is a graph which shows the result of evaluation regarding Young's modulus of an outer layer. It is a graph which shows the result of evaluation regarding Young's modulus of an outer layer. It is a graph which shows the relationship between the frequency and sound transmission loss in the conventional laminated glass.

  Hereinafter, an embodiment of a laminated glass according to the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of the laminated glass according to the present embodiment. As shown in the figure, the laminated glass according to the present embodiment includes an outer glass plate 1, an inner glass plate 2, and an intermediate film 3 sandwiched between these glasses. The outer glass 1 is a glass plate arranged on the side that is easily affected by disturbance, and the inner glass 2 is a glass plate arranged on the opposite side. Therefore, for example, when this laminated glass is used as a window glass of an automobile, the glass plate on the outside of the vehicle becomes the outer glass plate, and when it is used as a building material, the side facing the outside becomes the outer glass plate. However, depending on possible disturbances, the arrangement may be reversed. Hereinafter, each member will be described.

<1. Outer glass plate and inner glass plate>
As the outer glass plate 1 and the inner glass plate 2, known glass plates can be used, and they can be formed of heat ray absorbing glass, general clear glass or green glass, or UV green glass. However, when this laminated glass is used for a window glass of an automobile, it is necessary to realize visible light transmittance in accordance with safety standards of a country where the automobile is used. For example, the required solar absorptance can be ensured by the outer glass plate 1 and the visible light transmittance can be adjusted by the inner glass plate 2 to satisfy the safety standard. Hereinafter, an example of the composition of the clear glass and an example of the composition of the heat ray absorbing glass will be described.

(Clear glass)
SiO ₂ : 70 to 73% by mass
Al ₂ O ₃ : 0.6 to 2.4 mass%
CaO: 7 to 12% by mass
MgO: 1.0 to 4.5 mass%
R ₂ O: 13 to 15% by mass (R is an alkali metal)
Fe total iron oxide in terms of _{2 O 3 (T-Fe 2} O 3): 0.08~0.14 wt%

(Heat absorbing glass)
The composition of the heat-absorbing glass, for example, based on the composition of the clear glass, the proportion of the total iron oxide in terms of _{Fe 2 O 3 (T-Fe} 2 O 3) and 0.4 to 1.3 wt%, CeO ₂ is 0 to 2% by mass, the ratio of TiO ₂ is 0 to 0.5% by mass, and the skeleton components (mainly SiO ₂ and Al ₂ O ₃ ) of the glass are T-Fe ₂ O ₃ and CeO. ₂ and TiO ₂ can be reduced in composition.

  The outer glass plate 1 mainly needs to have durability and impact resistance against external obstacles. For example, when this laminated glass is used as a windshield of an automobile, the outer glass plate 1 has an impact resistance to flying objects such as pebbles. is necessary. From this viewpoint, the thickness of the outer glass plate 1 is preferably 1.8 mm or more, 1.9 mm or more, 2.0 mm or more, 2.1 mm or more, and 2.2 mm or more. On the other hand, the upper limit of the thickness of the outer glass is preferably in the order of 5.0 mm or less, 4.0 mm or less, 3.1 mm or less, 2.5 mm or less, 2.4 mm or less. Among these, it is preferable that it is larger than 2.1 mm and 2.5 mm or less, especially 2.2 mm or more and 2.4 mm or less.

  On the other hand, the thickness of the inner glass plate 2 needs to be smaller than that of the outer glass plate 1 in order to reduce the weight of the laminated glass. Specifically, as described later, it is preferable to be in a range of 1.2 mm ± 0.6 mm, which is susceptible to a frequency range of 2000 to 5000 Hz, which is a frequency range of a sound that is easy for a human to hear. Specifically, the thickness of the inner glass plate 2 is preferably in the order of 0.6 mm or more, 0.8 mm or more, 1.0 mm or more, and 1.3 mm or more. On the other hand, the upper limit of the thickness of the inner glass plate 2 is preferably 1.8 mm or less, 1.6 mm or less, 1.4 mm or less, 1.3 mm or less, and less than 1.1 mm. Among them, for example, the thickness is preferably 0.6 mm or more and less than 1.1 mm.

  Further, the shapes of the outer glass plate 1 and the inner glass plate 2 according to the present embodiment may be any of a planar shape and a curved shape. However, the curved shape of the STL is lower than that of the curved shape. It is considered that the STL value is lower in the curved shape than in the planar shape, because the effect of the resonance mode is larger in the curved shape.

  Further, when the glass has a curved shape, it is said that the sound insulation performance is reduced as the amount of doubling increases. The doubling amount is an amount indicating the bending of the glass plate. For example, as shown in FIG. 2, when a straight line L connecting the center of the upper side and the center of the lower side of the glass plate is set, The largest one of the distances is defined as the amount of doubling.

  FIG. 3 is a graph showing a result of simulating a relationship between a general frequency and an STL of a curved glass plate and a planar glass plate. According to FIG. 3, the curved glass plate has no large difference in STL when the amount of doubling is in the range of 30 to 38 mm, but the STL decreases in the frequency range of 4000 Hz or less compared to the flat glass plate. You can see that. Therefore, when producing a curved glass plate, the smaller the amount of doubling, the better. For example, when the amount of doubling exceeds 30 mm, as described later, the Young's modulus of the core layer of the intermediate film is set to 20 MPa (frequency (100 Hz, temperature 20 ° C.) or less.

  Here, an example of a method of measuring the thickness when the glass plate is curved will be described. First, as shown in FIG. 4, the measurement positions are two upper and lower positions on a center line S extending vertically in the center of the glass plate in the left-right direction. The measuring instrument is not particularly limited, but for example, a thickness gauge such as SM-112 manufactured by Teclock Corporation can be used. At the time of measurement, the glass plate is placed so that the curved surface of the glass plate rests on a flat surface, and the thickness is measured by holding the end of the glass plate with the thickness gauge. Note that, even when the glass plate is flat, the measurement can be performed in the same manner as when the glass plate is curved.

<2. Interlayer>
The intermediate film 3 is formed of a plurality of layers. As an example, as shown in FIG. 1, the intermediate film 3 can be formed of three layers in which a soft core layer 31 is sandwiched by a harder outer layer 32. . However, the present invention is not limited to this configuration, and may be formed of a plurality of layers having the soft core layer 31. For example, two layers including the core layer 31 (one core layer and one outer layer), or an odd number of five or more layers (one core layer and the outer layer) Can be formed of four layers) or an even number of layers including the core layer 31 inside (one core layer and the other layers are outer layers).

  The core layer 31 is softer than the outer layer 32. In this regard, a material can be selected based on Young's modulus. Specifically, at a frequency of 100 Hz and a temperature of 20 degrees, the pressure is preferably 1 to 20 MPa, more preferably 1 to 16 MPa. Further, the pressure is preferably 1 to 10 MPa. As a measurement method, for example, frequency dispersion measurement can be performed with a strain amount of 0.05% using a solid viscoelasticity measuring device DMA 50 manufactured by Metravib. Hereinafter, in this specification, the Young's modulus is a value measured by the above method unless otherwise specified. However, when the frequency is 200 Hz or less, the measured value is used, but when the frequency is higher than 200 Hz, the calculated value based on the measured value is used. The calculated value is based on a master curve calculated from the measured value by using the WLF method.

  On the other hand, the Young's modulus of the outer layer 32 is not particularly limited and may be larger than that of the core layer. For example, at a frequency of 100 Hz and a temperature of 20 degrees, the order is preferably 560 MPa or more, 650 MPa or more, 1300 MPa or more, and 1764 MPa or more. On the other hand, the upper limit of the Young's modulus of the outer layer 32 is not particularly limited, but can be set, for example, from the viewpoint of workability. For example, it is empirically known that when the pressure is 1750 MPa or more, workability, particularly cutting becomes difficult. When a pair of outer layers 32 sandwiching the core layer 31 is provided, it is preferable that the Young's modulus of the outer layer 32 on the outer glass plate 1 side be larger than the Young's modulus of the outer layer 32 on the inner glass plate 2 side. As a result, the resistance to breakage against external force from outside the vehicle or outdoors is improved.

  The tan δ of the core layer 31 of the intermediate film 3 is preferably 0.5 to 3.0, more preferably 0.7 to 2.0, and more preferably 1.0 to 2.0 at a frequency of 100 Hz and a temperature of 20 degrees. Particularly preferred is 1.5. When tan δ is within the above range, sound is easily absorbed, and sound insulation performance is improved. However, if it is larger than 3.0, the intermediate film 3 becomes too soft and difficult to handle, which is not preferable. On the other hand, if it is smaller than 0.5, the impact resistance is lowered, which is not preferable.

  On the other hand, the tan δ of the outer layer may be a value smaller than that of the core layer 31, and for example, can be determined between 0.1 and 3.0 at a frequency of 100 Hz and a temperature of 20 degrees.

  Further, the material constituting each of the layers 31 and 32 is not particularly limited, but it is necessary that at least the material has a Young's modulus within the above range. For example, the outer layer 32 can be made of polyvinyl butyral resin (PVB). Polyvinyl butyral resin is preferable because it has excellent adhesion to glass plates and penetration resistance. On the other hand, the core layer 31 can be made of an ethylene vinyl acetate resin (EVA) or a polyvinyl acetal resin softer than the polyvinyl butyral resin constituting the outer layer. By sandwiching the soft core layer therebetween, the sound insulation performance can be greatly improved while maintaining the same adhesiveness and penetration resistance as a single-layer resin interlayer.

  Generally, the hardness of the polyvinyl acetal resin is controlled by (a) the degree of polymerization of the starting polyvinyl alcohol, (b) the degree of acetalization, (c) the type of plasticizer, and (d) the proportion of the plasticizer added. Can be. Therefore, by appropriately adjusting at least one selected from these conditions, even with the same polyvinyl butyral resin, the hard polyvinyl butyral resin used for the outer layer and the soft polyvinyl butyral resin used for the core layer It can be made separately. Furthermore, the hardness of the polyvinyl acetal resin can also be controlled by the type of aldehyde used for acetalization, co-acetalization with a plurality of types of aldehydes, or pure acetalization with a single type of aldehyde. Although it cannot be said unconditionally, the polyvinyl acetal resin obtained by using an aldehyde having a large number of carbon atoms tends to be softer. Therefore, for example, when the outer layer is made of polyvinyl butyral resin, the core layer has an aldehyde having 5 or more carbon atoms (for example, n-hexyl aldehyde, 2-ethylbutyraldehyde, n-heptyl aldehyde, n- (Octyl aldehyde)) with polyvinyl alcohol. In addition, when a predetermined Young's modulus is obtained, it is not limited to the above resin and the like.

  Further, the total thickness of the intermediate film 3 is not particularly limited, but is preferably 0.3 to 6.0 mm, more preferably 0.5 to 4.0 mm, and more preferably 0.6 to 2.0 mm. It is particularly preferred that there is. On the other hand, the thickness of the core layer 31 is preferably from 0.1 to 2.0 mm, and more preferably from 0.1 to 0.6 mm. If the thickness is smaller than 0.1 mm, the influence of the soft core layer 31 is less likely to occur, and if the thickness is larger than 2.0 mm or 0.6 mm, the total thickness increases and the cost increases. On the other hand, the thickness of the outer layer 32 is not particularly limited, but is preferably, for example, 0.1 to 2.0 mm, and more preferably 0.1 to 1.0 mm. In addition, the total thickness of the intermediate film 3 may be fixed, and the thickness of the core layer 31 may be adjusted.

  The thickness of the core layer 31 can be measured, for example, as follows. First, the cross section of the laminated glass is magnified and displayed 175 times by a microscope (for example, VH-5500 manufactured by Keyence Corporation). Then, the thickness of the core layer 31 is visually identified and measured. At this time, in order to eliminate visual variations, the number of measurements is set to five, and the average value is set as the thickness of the core layer 31. For example, an enlarged photograph of the laminated glass as shown in FIG. 5 is taken, and the thickness is measured by specifying the core layer in the photograph.

  Note that the thickness of the intermediate film 3 does not need to be constant over the entire surface, and may be, for example, a wedge shape for a laminated glass used in a head-up display. In this case, the thickness of the intermediate film 3 is measured at the point where the thickness is the smallest, that is, at the lowermost side of the laminated glass. When the intermediate film 3 is wedge-shaped, the outer glass plate 1 and the inner glass plate 2 are not arranged in parallel, but such an arrangement is also included in the “opposite arrangement” of the outer glass plate and the inner glass plate in the present invention. And That is, the “facing arrangement” of the present invention includes, for example, the arrangement of the outer glass plate 1 and the inner glass plate 2 when the intermediate film 3 whose thickness increases at a rate of change of 3 mm or less per meter is used.

  The method for producing the intermediate film 3 is not particularly limited. For example, after blending a resin component such as the polyvinyl acetal resin described above, a plasticizer and other additives as necessary, and uniformly kneading, the respective layers are collectively mixed. And a method of laminating two or more resin films formed by this method by a pressing method, a laminating method, or the like. The resin film before lamination used in a method of laminating by a pressing method, a lamination method, or the like may have a single-layer structure or a multilayer structure.

<3. Manufacturing method of laminated glass>
The method for manufacturing a laminated glass according to the present embodiment is not particularly limited, and a conventionally known method for manufacturing a laminated glass can be employed. For example, first, the intermediate film 3 is sandwiched between the outer glass plate 1 and the inner glass plate 2, placed in a rubber bag, and preliminarily bonded at about 70 to 110 ° C. while suctioning under reduced pressure. Other methods can be used for the preliminary bonding. For example, the intermediate film 3 is sandwiched between the outer glass plate 1 and the inner glass plate 2 and heated at 45 to 65 ° C. in an oven. Subsequently, the laminated glass is pressed by a roll at 0.45 to 0.55 MPa. Next, the laminated glass is again heated at 80 to 105 ° C. by an oven, and then pressed again by a roll at 0.45 to 0.55 MPa. Thus, the preliminary bonding is completed.

  Next, the actual bonding is performed. The pre-bonded laminated glass is fully bonded by an autoclave at 8 to 15 atm and at 100 to 150 ° C. Specifically, the actual bonding can be performed at 145 ° C. at 14 atm. Thus, the laminated glass according to the present embodiment is manufactured.

<4. Laminated glass mounting structure>
The above-mentioned laminated glass can be attached to an attachment structure such as an automobile and a building. At this time, the laminated glass is mounted on the mounting structure via the mounting portion. The attachment portion corresponds to, for example, a frame such as a urethane frame for attaching to an automobile, an adhesive, a clamp, or the like. 6A, first, pins 50 are attached to both ends of the laminated glass 10, and an adhesive 60 is applied to a frame 70 of the automobile to be attached. . A through hole 80 into which the pin is inserted is formed in the frame. Then, as shown in FIG. 6B, the laminated glass 10 is attached to the frame 70. First, the pins 50 are inserted into the through holes 80, and the laminated glass 10 is temporarily fixed to the frame 70. At this time, since the step is formed in the pin 50, the pin 50 is inserted only halfway through the through hole 80, and thereby a gap is generated between the frame 70 and the laminated glass 10. Since the above-described adhesive 60 is applied to the gap, the laminated glass 10 and the frame 70 are fixed via the adhesive 60 as time passes.

  In the mounting of the laminated glass to the mounting structure, it is preferable that the mounting angle θ of the laminated glass 10 be 45 degrees or less from the vertical N as shown in FIG.

<5. Features>
According to the present embodiment, the following effects can be obtained by setting the Young's modulus of the core layer 31 constituting a part of the intermediate film 3 to a small value of 1 to 20 MPa at a frequency of 100 Hz and a temperature of 20 degrees. . First, if the Young's modulus of the interlayer is large, even if it is a laminated glass, the properties as a single plate become strong. Further, as shown in the following mathematical formula, generally, as the thickness and Young's modulus of glass decrease, the coincidence frequency shifts to a higher frequency side.

  Considering these, for example, if the Young's modulus of the intermediate film 3 is large, even if the total thickness of the laminated glass is 4 mm, the coincidence frequency becomes 3 to 4 kHz as in the case of a single plate having a thickness of 4 mm. However, performance deteriorates in the frequency band where it is easy to hear. On the other hand, if the Young's modulus is small, the performance of the laminated glass is the sum of the two glass plates. For example, in the case of a laminated glass composed of a 2 mm glass plate and a 1 mm glass plate, the performance tends to be the sum of the performances of the two glass plates. That is, since the thickness of each glass plate shown in FIG. 7 is smaller than 4 mm, the coincidence frequency shifts to the high frequency side, and a 2 mm glass plate has a coincidence frequency around 5000 Hz, and a 1 mm glass plate has a coincidence frequency of 8000 Hz. There is a frequency. And since the performance of the laminated glass of these 1 mm and 2 mm glass plates is the sum of them, the coincidence frequency will be between 5000 and 8000 Hz. FIG. 7 is a graph showing the result of simulating the relationship between the frequency and the STL of a single plate that is not a laminated glass.

  Therefore, in the present embodiment, since the Young's modulus of the core layer 31 constituting a part of the intermediate film 3 is set to 1 to 20 MPa at a frequency of 100 Hz and a temperature of 20 degrees, the performance of the laminated glass is equal to that of the outer glass plate 1 and the inner glass plate. The sum with the glass plate 2 is set. Thereby, even if the thickness of the inner glass plate 2 is made as small as 0.4 to 2.0 mm, the sound insulation performance does not decrease at a frequency that is easy for humans to hear. That is, by reducing the thickness of the inner glass plate 2, the coincidence frequency shifts to the higher frequency side. Therefore, as described above, it is possible to increase the sound transmission loss reduced in the frequency range of 2000 to 5000 Hz due to the thinning of the inner glass plate 2. As a result, it is possible to reduce the weight of the laminated glass and improve the sound insulation performance in a frequency range of 2000 to 5000 Hz that is easy for humans to hear.

  Further, the present inventors have found that when the Young's modulus of the outer layer 32 of the intermediate film 3 is improved, the sound insulation performance in a frequency range of about 4000 Hz or more is improved. For example, when the outer layer 32 having a Young's modulus of 560 MPa (20 ° C., 100 Hz) is used for an outer layer having a Young's modulus of 441 MPa (20 ° C., 100 Hz), the STL becomes 0.3 dB at a frequency of 6300 Hz. Found to improve. Generally, it is said that a human can recognize a change of sound of 0.3 dB or more. Therefore, by increasing the Young's modulus, it is possible to obtain a sound insulation effect that can be recognized by a human in a high frequency range. It has been found that the higher the Young's modulus of the outer layer 32, the higher the sound insulation performance. For example, when the Young's modulus is 880 MPa (20 ° C., 100 Hz) or more, the STL is 1.0 dB or more at a frequency of 6300 Hz. It has been found that the STL is further improved when the pressure is 1300 MPa (20 ° C., 100 Hz) or more.

  On the other hand, in a low frequency range of 1000 to 3500 Hz, it is known that the STL decreases when the Young's modulus of the outer layer is improved. However, the reduction has also been found to be small.

  Hereinafter, examples of the present invention will be described. However, the present invention is not limited to the following examples.

<1. Evaluation of Outer Glass Plate Thickness>
First, the thickness of the outer glass plate was evaluated. Here, the following seven laminated glasses were prepared. Each laminated glass is composed of an outer glass plate, an inner glass plate, and an interlayer film sandwiched therebetween. In the intermediate film, the thickness of the core layer and the outer layer were 0.1 mm and 0.33 mm, respectively, and the Young's modulus was 10 MPa and 441 MPa (20 ° C., 100 Hz), respectively.

  Each of the laminated glasses was arranged at an angle of 60 degrees from the vertical, and granite having an average particle size of about 5 to 20 mm was collided with each of the laminated glasses at a speed of 64 km / h. 30 pieces of granite were made to collide with each laminated glass, and the crack occurrence rate was calculated. The result is as shown in FIG. As shown in the figure, in the laminated glasses 1 to 4 in which the thickness of the outer glass plate was 2.0 mm, the crack generation rate was 5% or less regardless of the thickness of the inner glass plate. On the other hand, in the laminated glasses 5 and 6 in which the thickness of the outer glass plate was 1.8 mm or less, the crack occurrence rate was 8% regardless of the thickness of the inner glass. Accordingly, from the viewpoint of impact resistance to flying objects, the thickness of the outer glass plate is preferably 1.8 mm or more as described above. More preferably, it is 2.0 mm or more.

<2. Evaluation of Young's Modulus of Core Layer>
As described below, laminated glasses according to Examples and Comparative Examples were prepared.

  Each glass plate was formed of the above-mentioned clear glass. The intermediate film was composed of a core layer and a pair of outer layers sandwiching the core layer. The thickness of the intermediate film was 0.76 mm, the thickness of the core layer was 0.1 mm, and the thickness of both outer layers was 0.33 mm. The Young's modulus of both outer layers was adjusted to 441 MPa (20 ° C., 100 Hz).

  About the said Example and the comparative example, the sound transmission loss was evaluated by simulation. The simulation conditions are as follows.

First, the simulation was performed using acoustic analysis software (ACTRAN, manufactured by Free Field Technology). With this software, the sound transmission loss (transmitted sound pressure level / incident sound pressure level) of the laminated glass can be calculated by solving the following wave equation using the finite element method.

Next, calculation conditions will be described.
(1) Model setting FIG. 9 shows a model of the laminated glass used in this simulation. In this model, a laminated glass laminated in the order of an outer glass plate, an intermediate film, an inner glass plate, and a urethane frame from a sound source side is defined. Here, the urethane frame is added to the model because the presence or absence of the urethane frame is considered to have a considerable effect on the calculation result of the sound transmission loss, and between the laminated glass and the windshield of the vehicle This is because it is generally considered that a urethane frame is used and adhered.
(2) Input condition 1 (dimensions, etc.)

  The dimensions of the glass plate, 800 × 500 mm, are smaller than the size used in an actual vehicle. The larger the glass size, the lower the STL value tends to be. This is because the larger the size, the larger the constrained portions and the larger the resonance mode. However, even if the glass sizes are different, the tendency of the relative value for each frequency, that is, the laminated glass made of glass plates having different thicknesses becomes worse in a predetermined frequency band as compared with the laminated glass made of glass plates having the same thickness. The trend is the same.

The random diffused sound wave shown in Table 3 is a sound wave having a predetermined frequency and transmitted to the outer glass plate at an incident angle in all directions, and is a sound source in a reverberation chamber for measuring sound transmission loss. Is assumed.
(3) Input condition 2 (physical property value)
[Young modulus and loss coefficient of core layer and both outer layers]
Different values were used for each major frequency. This is because the core layer and both outer layers are viscoelastic and the Young's modulus is strongly frequency dependent due to the viscous effect. In addition, although the temperature dependency is large, physical property values assuming constant temperature (20 ° C.) were used in this case.
The above simulation method is the same for the following items 3, 4, and 5.

  The results are as shown in the graph of FIG. According to this result, as in Examples 1 to 4, the STL value due to the different thickness can be suppressed by setting the Young's modulus of the core layer to 20 MPa (20 ° C., 100 Hz) or less. Further, by setting the Young's modulus of the core layer to 16 MPa (20 ° C., 100 Hz) or less as in Examples 2 to 4, compared to Comparative Example 1 in which both glasses have the same thickness, in a frequency range of 2000 to 5000 Hz. Sound transmission loss is high. Further, as in Examples 3 and 4, by setting the Young's modulus of the core layer to 10 MPa (20 ° C., 100 Hz) or less, compared to Comparative Example 1 in which both glasses have the same thickness, in the frequency range of 2000 to 5000 Hz. The sound transmission loss is clearly higher. Therefore, it was found that by making the inner glass plate thinner than the outer glass plate and setting the Young's modulus of the core layer to 20 MPa or less, the sound insulation performance in the 2000-5000 Hz frequency range that is easy for humans to hear is improved.

<3. Evaluation of core layer thickness>
As described below, laminated glasses according to Examples and Comparative Examples were prepared. Here, the thickness of the core layer was changed, and the sound transmission loss was calculated by the above simulation method. The intermediate film was composed of three layers, and the thicknesses of the core layer and the outer layer were changed without changing the total thickness. The Young's modulus of the core layer was 10 MPa (20 ° C., 100 Hz), and the Young's modulus of the outer layer was 441 Mpa (20 ° C., 100 Hz). The thicknesses of the outer glass plate and the inner glass plate were 2.0 mm and 1.0 mm, respectively.

  About the said Example and the comparative example, the sound transmission loss was evaluated by simulation. The results are as shown in FIG. According to the figure, it can be seen that when the thickness of the core layer is smaller than 0.1 mm, the sound transmission loss is reduced in the frequency range of 2000 to 5000 Hz. Therefore, in order to enhance the sound insulation performance in the frequency range of 2000 to 5000 Hz that is easy for humans to hear, it is preferable that the thickness of the core layer be 0.1 mm or more.

<4. Evaluation on Mounting Angle of Laminated Glass>
Subsequently, the mounting angle of the laminated glass was evaluated by a simulation in which the incident angle of sound was changed. Here, the sound transmission loss was calculated by changing the angle from the vertical to 0 to 75 degrees. Each glass plate was formed of the above-mentioned clear glass. The intermediate film was composed of a core layer and a pair of outer layers sandwiching the core layer. The thickness of the intermediate film was 0.76 mm, the thickness of the core layer was 0.1 mm, and the thickness of both outer layers was 0.33 mm. The Young's modulus of the core layer was 10 MPa (20 ° C., 100 Hz), and the Young's modulus of both outer layers was 441 MPa (20 ° C., 100 Hz). The thickness of the glass plate was 2.0 mm and 1.0 mm.

  About the said Example and the comparative example, the sound transmission loss was evaluated by the said simulation method. However, a simulation was performed by adding a mounting angle of the laminated glass as an input condition. The results are as shown in FIG. According to the figure, it can be seen that when the mounting angle exceeds 60 degrees, the sound transmission loss sharply decreases at a frequency near 3000 Hz. Therefore, in order to enhance the sound insulation performance in the frequency range of 2000 to 5000 Hz that is easy for humans to hear, it has been found that it is preferable that the mounting angle of the laminated glass from the vertical be 45 degrees or less. If the angle is 60 degrees or less, the sound insulation performance can be enhanced. In some cases, if the angle is 75 degrees or less, the sound insulation performance can be enhanced.

<5. Evaluation of Young's modulus of outer layer>
In order to evaluate the Young's modulus of the outer layer, laminated glasses according to Examples and Comparative Examples were prepared as follows. Here, while the thicknesses of the outer glass and the inner glass were kept constant, the Young's modulus of the outer layer and the core layer of the intermediate film were changed, and the sound transmission loss was calculated by the above simulation method. Each glass plate was formed of the above-mentioned clear glass, and the intermediate film was composed of a core layer and a pair of outer layers sandwiching the core layer. The thickness of the intermediate film was 0.76 mm, the thickness of the core layer was 0.1 mm, and the thickness of both outer layers was 0.33 mm.

  The results are as follows. First, FIG. 13 shows the results of Examples 13 and 14. In the evaluation of the Young's modulus of the core layer described above, it was found that when the Young's modulus was set to 20 MPa or less, the sound transmission loss was high in a frequency range of 2000 to 5000 Hz that is easy for humans to hear. On the other hand, in Examples 13 and 14, the Young's modulus of the outer layer was changed while the Young's modulus of the core layer was kept constant. As a result, as shown in FIG. 13, it was found that in Example 14 in which the outer layer had a high Young's modulus, the sound transmission loss was high in a high frequency region of 5000 Hz or more.

  In Examples 15 to 18, the Young's modulus of the core layer was further reduced, and the Young's modulus of the outer layer was increased. As shown in FIG. 14, in these examples, although the sound transmission loss in the frequency region of 2000 to 5000 Hz is higher than those in Examples 13 and 14, the higher the transmission speed in the Examples 13 and 14 is 5000 Hz or more. Sound transmission loss in the frequency domain is not high. In particular, when the Young's modulus of the outer layer exceeds 1764 MPa, the sound transmission loss in a high frequency region of 5000 Hz or more hardly increases.

Reference Signs List 1 outer glass plate 2 inner glass plate 3 interlayer film 31 core layer 32 outer layer

Claims (11)

With laminated glass,
A mounting portion to which the laminated glass can be mounted, such that a mounting angle from the vertical at the lower end of the laminated glass is 45 degrees or less,
With
The laminated glass is
An outer glass plate,
An inner glass plate disposed to face the outer glass plate,
An intermediate film sandwiched between the outer glass plate and the inner glass plate,
With
The thickness of the inner glass plate is 0.6 to 1.8 mm,
The thickness of the outer glass plate is equal to or greater than the thickness of the inner glass plate,
The intermediate film is composed of a plurality of layers including at least a core layer,
The laminated glass mounting structure, wherein the Young's modulus of the core layer is 1 to 20 MPa at a frequency of 100 Hz and a temperature of 20 ° C., and is lower than the Young's modulus of the other layers.   The laminated glass mounting structure according to claim 1, wherein the thickness of the core layer is 0.1 to 0.6 mm.   The mounting structure for laminated glass according to claim 1 or 2, wherein the thickness of the inner glass plate is 0.8 to 1.6 mm.   The mounting structure for laminated glass according to claim 1 or 2, wherein the thickness of the inner glass plate is 1.0 to 1.4 mm.   The mounting structure for laminated glass according to claim 1 or 2, wherein the thickness of the inner glass plate is 0.8 to 1.3 mm.   The mounting structure for a laminated glass according to any one of claims 1 to 5, wherein the thickness of the outer glass plate is 1.8 to 5.0 mm.   The laminated glass mounting structure according to any one of claims 1 to 6, wherein the core layer has a Young's modulus of 1 to 16 MPa at a frequency of 100 Hz and a temperature of 20 ° C.   The laminated glass mounting structure according to any one of claims 1 to 7, wherein the intermediate film has at least one outer layer having a Young's modulus of 560 MPa or more at a frequency of 100 Hz and a temperature of 20 ° C in contact with the core layer. .   The laminated glass mounting structure according to any one of claims 1 to 8, wherein tan δ of the core layer is 0.5 to 3.0 at a frequency of 100 Hz and a temperature of 20 ° C. The intermediate film has at least one outer layer in contact with the core layer,
The laminated glass mounting structure according to any one of claims 1 to 9, wherein, at a frequency of 100 Hz and a temperature of 20 ° C, tan δ of the outer layer is smaller than tan δ of the core layer. When a straight line connecting the center of the upper side and the center of the lower side of the inner glass plate is set, the laminated glass is curved such that the maximum distance between the straight line and the inner glass plate is larger than 30 mm. Item 14. A laminated glass mounting structure according to any one of Items 1 to 10.