JP4594506B2 - Method for manufacturing damping material - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a vibration damping material that reuses paint candy.
[0002]
[Prior art]
When manufacturing automobiles, uncoated paint, so-called paint soot, is discharged. That is, when the automobile body is painted, the paint is sprayed from the coating device toward the automobile body, but this paint has a portion that drops without being applied to the automobile body. Usually, since the coating of the paint on the automobile body is repeated a plurality of times, the amount of paint soot is considerable.
[0003]
The treatment of paint candy is generally outsourced to a waste disposal contractor. However, entrusting the processing of the paint cake to a contractor has a problem that the waste disposal cost increases.
[0004]
Therefore, it is recalled that the paint cake is incinerated. However, in this treatment method, since the main component of the paint cake is a thermosetting resin, CO, CO ₂ , and in some cases, a chlorinated organic gas is generated during incineration. For this reason, it is hard to say that this is an environmentally preferable treatment method.
[0005]
In order to solve such problems, it is currently attempted to reuse the paint bowl. For example, it has been proposed to use a material obtained by drying the paint cake as a raw material for a vibration damping sheet for an automobile body. In this case, since the paint cake is not incinerated, CO, CO ₂ , chlorinated organic gas, etc. are not generated. Moreover, since the paint cake can be processed without entrusting a contractor, the waste processing cost is not increased.
[0006]
A vibration damping sheet for an automobile body is joined to a member constituting the automobile body, such as a floor panel, by thermal welding or the like. And when a motor vehicle drive | works, it suppresses that a vibration and noise are transmitted from the outer side of a motor vehicle body to the inside of a vehicle.
[0007]
Such a vibration damping sheet is usually composed of an asphalt material as a main component and further blended with a pigment or the like as necessary.
[0008]
[Problems to be solved by the invention]
By the way, the above-described method for reusing a coating cake has a drawback that an organic compound odor such as a thinner odor is emitted from the vibration damping sheet because the coating cake is added to the vibration damping sheet. Moreover, when this vibration damping sheet is thermally welded to an automobile body, foaming occurs because hydrogen atoms, nitrogen atoms, oxygen atoms, etc. are dissociated from the thermosetting resin, which is the main component of the paint soot, to generate gas. As a result, so-called swelling occurs in the vibration damping sheet.
[0009]
In order to solve this kind of drawback, Japanese Patent Application Laid-Open No. 10-43711 proposes a method for treating paint waste (paint soot) in which the paint soot is heat treated and pulverized and then reheated. . However, in this treatment method, organic compound components such as thinner are only volatilized and removed from the paint soot, so that the vibration damping sheet is swollen when the vibration damping sheet is thermally welded to the automobile body. There is a problem that it cannot be avoided reliably.
[0010]
In addition, in this case, if the heat treatment is performed twice with one heat treatment apparatus, the processing efficiency of the paint cake is lowered. On the other hand, if two heat treatment apparatuses are installed in order to treat the paint cake efficiently, a large capital investment is required, resulting in a disadvantage that the processing cost of the paint cake increases.
[0011]
The present invention has been made to solve the various problems described above, and even when the paint cake is reused as a raw material, the organic compound odor emitted when bonded to an automobile body or the like is remarkably reduced. In addition, an object of the present invention is to provide a method for manufacturing a vibration damping material in which the occurrence of swelling is significantly suppressed.
[0012]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the present invention provides a vibration damping material that suppresses transmission of vibration, wherein the carbon material produced by carbonization of the paint cake contains at least an asphalt material. It is characterized by being added to.
[0013]
In this vibration damping material, a carbon material obtained by carbonizing the paint cake is carbonized as part of the raw material. That is, since the paint bowl is reused, resource saving can be achieved. Further, when carbonizing the paint cake by carbonization, generation of CO, CO ₂ , chlorinated organic gas, etc. is remarkably suppressed. For this reason, environmental protection can also be achieved.
[0014]
In addition, since the paint soot is completely carbonized, it is possible to avoid the generation of an organic compound odor and to avoid the occurrence of swelling when the vibration damping material is joined to the workpiece.
[0015]
In addition, the carbon material is a porous body having a large specific surface area with a large volume of open pores. For this reason, this vibration damping material exhibits deodorizing ability.
[0016]
As a suitable example of such a damping material, a damping sheet joined to a member constituting an automobile body can be exemplified.
[0017]
Furthermore, the present invention provides a carbonization step for producing a carbon material by carbonizing a paint cake by carbonization, a mixing step of adding the carbon material to a composition containing at least an asphalt material, and molding the mixture. And a molding step.
[0018]
A carbon material can be obtained in a high yield by carbonizing the paint cake. In this case, since the heat treatment of the paint cake is performed in a state where air or the like is shut off, it is possible to prevent the generated carbon material from reacting with oxygen or the like to generate CO or CO _2. .
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of a method for manufacturing a vibration damping material according to the present invention will be described in detail with reference to the accompanying drawings.
[0020]
First, FIG. 1 shows a schematic overall perspective view of a floor panel constituting an automobile. A propeller shaft housing portion 12 and a front wheel drive shaft housing portion 14 are provided on the left side of the floor panel 10 in FIG. 1. The propeller shaft housing portion 12 and the front wheel drive shaft housing portion 14 provide first to first drive shaft housing portions 14. Four sections 16a to 16d are formed. Among these, a driver's seat (not shown) is arranged on the first and second compartments 16a and 16b, while a passenger seat (not shown) is arranged on the third and fourth compartments 16c and 16d. The Further, on the right side of the floor panel 10 in FIG. 1, a rear seat placing portion 18, a tire house 20, and a spare tire accommodating portion 22 are provided.
[0021]
And the vibration and noise which arise when a car runs are in front of propeller shaft accommodating part 12, the 1st-4th division 16a-16d, rear seat mounting part 18, and spare tire accommodating part 22, respectively. A vibration damping sheet 24 for suppressing transmission to the inside of the vehicle is joined. That is, the vibration damping sheet 24 also functions as a damping material.
[0022]
The vibration damping sheet 24 includes an asphalt material and a carbon material 26 whose schematic cross section is shown in FIG. Among these, the asphalt material is the main component of the vibration damping sheet 24.
[0023]
The carbon material 26 is produced by carbonization of the paint soot discharged in the automobile body painting process. In this case, the main component of the paint cake is a thermosetting resin such as an acrylic resin, a polyester resin, a polyurethane resin, a melamine resin, a urea resin, or a benzoguanamine resin. A carbon material 26 is obtained by dissociating hydrogen atoms, nitrogen atoms, and the like.
[0024]
The vibration damping sheet 24 can be manufactured as follows.
[0025]
First, in the carbonization step, the carbon material 26 is generated by carbonization of the paint cake. In this case, the carbonization step includes a first pulverization step S1, a dehydration step S2, a heat treatment step S3, and a second pulverization step S4, as shown in the flowchart of FIG.
[0026]
Specifically, in the first pulverization step S1, as shown in FIG. 4, the paint cake 27 discharged in the automobile body painting step is pulverized by a pulverizer 28 to obtain a lump having an average diameter of about 5 mm. That is, after the paint cake 27 stored in the container 30 is put into the hopper 32, it is conveyed to the pulverizer 28 by the conveyor 34 facing the bottom of the hopper 32. The paint cake 27 is roughly pulverized in the pulverizer 28. The paint bowl 27 may contain an organic solvent such as thinner, a color pigment, an extender pigment, a dispersant, an ultraviolet absorber, a diluent, and moisture.
[0027]
The coarsely pulverized paint cake 27 is continuously discharged by a conveyor 36 and conveyed to a dehydrator 38.
[0028]
Next, in the dehydration step S <b> 2, the paint basket 27 is dehydrated by the dehydrator 38. This dehydration is preferably carried out until the water content of the paint bowl 27 becomes 40% or less. When the water content is higher than 40%, it takes a long time to evaporate the water when the paint cake 27 is heat-treated in the heat treatment step S3, so that the carbonization efficiency of the paint cake 27 is lowered. Because.
[0029]
The dehydrated paint bowl 27 is fed by a conveyor 40 to a heat treatment apparatus 42 whose interior has been previously raised to a certain temperature. The heat treatment apparatus 42 is sealed so that an oxidizing gas such as air does not enter the heat treatment apparatus 42.
[0030]
In the heat treatment step S3, the paint cake 27 is carbonized in the heat treatment apparatus 42. The temperature at this time is preferably 350 to 550 ° C. If the temperature is lower than 350 ° C., the reaction rate of the paint cake 27 decreases, so the yield of the carbon material 26 decreases. When the temperature is higher than 550 ° C., when the air is mixed in the heat treatment apparatus 42, the carbon material 26 is oxidized by oxygen in the air to generate CO and CO ₂ . A more preferable temperature is 400 to 500 ° C.
[0031]
The heat treatment apparatus 42 has a pair of screw conveyors 44a and 44b arranged in parallel with each other, and includes a heat source 46 below. The paint cake 27 that has undergone the dehydration step S2 is put into the hopper 47 of the heat treatment device 42 and is heat-treated by the heat source 46 while being conveyed by the screw conveyors 44a and 44b.
[0032]
By this heat treatment, an organic solvent such as moisture and thinner is evaporated from the paint bowl 27, and the thermosetting resin remains as a residue. Finally, the thermosetting resin is carbonized to generate an aggregate 48 of the carbon material 26. That is, since there is no oxidizing gas, the thermosetting resin is carbonized by dry distillation up to the carbon material 26 under the heating action of the heat source 46 without generating CO, CO ₂ or the like. As a result, the carbon material 26 is produced with a high yield. Further, the pigment contained in the paint bowl 27 changes to an inorganic compound.
[0033]
Next, the aggregate 48 of the carbon material 26 conveyed through the conveyor 50 is pulverized to a particle size according to the purpose and application by the pulverizer 52 in the second pulverization step S4, and the carbon material shown in FIG. 26 is obtained. It should be noted that the amount of the inorganic compound produced is extremely small and therefore does not affect the properties of the carbon material 26.
That is, it is not particularly necessary to separate the carbon material 26 and the inorganic compound from each other.
[0034]
Of course, the finely pulverized carbon material 26 may be classified as necessary.
[0035]
Thus, by carbonizing the paint cake 27, in other words, the carbon material 26 can be easily obtained by heat-treating the paint cake 27 in a state where the concentration of oxygen is extremely low.
[0036]
As can be understood from FIG. 2, the obtained carbon material 26 is a porous body having a large specific surface area having a large volume of open pores 56 therein.
[0037]
Next, in the mixing step, the carbon material 26 is added to a composition containing asphalt material as a main component to form a mixture (sheet body material). The addition ratio of the carbon material 26 is set within a range in which both are satisfactorily joined to each other when the damping sheet 24 described later is joined to the floor panel 10. When the addition ratio of the carbon material 26 is excessive, the vibration damping sheet 24 is not satisfactorily bonded to the floor panel 10. Specifically, it is sufficient if the ratio of the carbon material 26 in the sheet material is about 8 to 10% by weight.
[0038]
If necessary, pigments, fillers, and the like may be added to the composition to form a sheet material.
[0039]
Finally, in the forming step, the sheet material is formed into a sheet body having a predetermined thickness by a roll forming apparatus or a press forming apparatus (not shown), and then the sheet body is cut into a predetermined shape to obtain the vibration damping sheet 24. To be done.
[0040]
The vibration damping sheet 24 is joined to the front of the propeller shaft housing portion 12, the first to fourth sections 16 a to 16 d, the rear seat placement portion 18, the bottom surface of the spare tire housing portion 22, and the like by heat welding or the like. At this time, since the paint basket 27 is completely carbonized to become the carbon material 26, it is avoided that an organic compound odor is emitted from the vibration damping sheet 24. Further, since no hydrocarbon gas or CO ₂ is generated, the occurrence of foaming from the vibration damping sheet 24 is also avoided. That is, it is possible to remarkably suppress the swelling of the vibration damping sheet 24.
[0041]
In addition, the carbon material 26 is obtained by carbonizing the paint cake 27 by dry distillation. That is, since the vibration damping sheet 24 is manufactured by reusing the paint bowl 27, it is possible to save resources. Further, when carbonizing the paint tank 27, the generation of CO, CO ₂ , chlorinated organic gas, etc. is remarkably suppressed, so that the environment can be protected.
[0042]
Further, the carbon material 26 is a porous body having a large volume of open pores 56 as described above (see FIG. 2). For this reason, the carbon material 26 also functions as a deodorant.
[0043]
In other words, in the interior of an automobile that has just been completed, odorous components are emitted from the resin material, which is a constituent material of the instrument panel, and the seat cover fabric (moquette, etc.). It is collected in the pores 56. In other words, in the automobile including the floor panel 10 to which the vibration damping sheet 24 is joined, the odor component in the vehicle is adsorbed and removed by the vibration damping sheet 24. As a result, it is possible to remarkably reduce the odor in the vehicle immediately after completion.
[0044]
The deodorizing action of the vibration damping sheet 24 is sufficiently performed even when the addition ratio of the carbon material 26 is within the above-described range.
[0045]
In the above-described embodiment, the vibration damping sheet 24 joined to the floor panel 10 that is a member constituting the automobile body is exemplified as the vibration damping material, but is not particularly limited thereto. For example, it can also be used as a vibration damping material for a device such as a refrigerator that preferably performs vibration damping. Furthermore, you may make it use the damping material which concerns on this invention as a deodorizing material or a damping material.
[0046]
【Example】
A modified asphalt material, mica (silicate) as a special pigment, calcium carbonate as an extender pigment, and calcium oxide as a swelling inhibitor are mixed in a ratio of 46: 28: 8: 1.5 (weight ratio). It was set as the composition. And after mixing this composition and the carbon material 26 obtained by carbonizing the paint cake 27 in various ratios, the damping sheet 24 was obtained by shape | molding in a sheet form with a roll forming apparatus.
[0047]
Each of the obtained vibration damping sheets 24 was evaluated for dropability, adhesion, vibration damping properties, and deodorizing ability. The relationship between each of these characteristics and the addition ratio of the carbon material is shown as a graph in FIGS.
[0048]
In addition, as shown in FIG. 9, the drop-in property is obtained by heating the vibration damping sheet 24 under substantially the same condition as in the case of heat welding after placing the vibration damping sheet 24 on the opening end of the container 58 without looseness. In this case, as shown in FIG. 10, the distance h dropped toward the inside of the container 58 due to the extension of the central portion of the vibration damping sheet 24 was measured and evaluated. It indicates that the greater the distance h, the easier it is to deform with respect to heat, and thus the easier it is to join along the shape of the floor panel 10.
[0049]
Further, the adhesion is determined by mechanically peeling the vibration damping sheet 24 after cooling the vibration damping sheet 24 thermally welded to the workpiece (not shown) together with the workpiece, and remaining the vibration damping sheet 24 on the workpiece surface at that time. The area ratio was calculated and evaluated. It shows that it is what adhere | attaches favorably with respect to a workpiece | work (floor panel 10), so that this value is large.
[0050]
Further, the vibration damping property was evaluated by measuring the loss coefficient at 20 ° C. and 40 ° C. of each vibration damping sheet 24. The larger the loss factor, the more difficult it is to transmit vibration.
[0051]
The deodorizing ability was evaluated by housing the vibration damping sheet 24 and the general wastewater sludge in a container (not shown) capable of measuring the concentration of the odor component, and measuring the concentration of the odor component after a predetermined time has elapsed. . It shows that it is what was excellent in the deodorizing ability, so that this value is small.
[0052]
From FIG. 5 to FIG. 8, the vibration damping sheet 24 to which the carbon material is added is excellent in dropability, adhesion and vibration damping properties, and the vibration damping sheet 24 can adsorb and remove odor components of general wastewater sludge. it is obvious.
[0053]
From FIG. 6, FIG. 7 and FIG. 8, it is understood that the deodorizing ability of the vibration damping sheet 24 improves as the carbon material addition ratio increases, but the loss coefficient and adhesion at 40 ° C. tend to decrease. Is done. Therefore, it can be said that the addition ratio of the carbon material is preferably 8 to 10% by weight in order to obtain the vibration damping sheet 24 having these characteristics in a well-balanced manner.
[0054]
【The invention's effect】
As described above, according to the vibration damping material of the present invention, the carbon material obtained by carbonization of the paint cake is contained. That is, since the paint cake is reused, resource saving and environmental protection can be achieved. In addition, since the paint cake is completely carbonized, it is possible to avoid the generation of an organic compound odor from the vibration damping material and the occurrence of swelling when the vibration damping material is joined to the workpiece.
[0055]
Furthermore, since the carbon material functions as a deodorizer, the vibration damping sheet can also adsorb and remove odors in the vehicle.
[0056]
Further, according to the method for manufacturing a vibration damping material according to the present invention, the carbonized material is obtained by carbonizing the paint cake by dry distillation. That is, since the heat treatment of the paint candy is performed in a state in which air or the like is shut off, it can be avoided that the generated carbon material reacts with oxygen or the like to generate CO or CO _2. A carbon material can be obtained with a high yield.
[Brief description of the drawings]
FIG. 1 is a schematic overall perspective view of a floor panel to which a vibration damping sheet according to the present embodiment is bonded.
FIG. 2 is a schematic cross-sectional configuration diagram of a carbon material contained in the vibration damping sheet of FIG.
FIG. 3 is a flowchart of a carbonization process of the carbon material.
FIG. 4 is an overall schematic explanatory view of equipment for producing the carbon material.
FIG. 5 is a graph showing the relationship between the carbon material addition ratio and dropability in the vibration damping sheet according to the present embodiment.
FIG. 6 is a graph showing the relationship between the carbon material addition ratio and adhesion in the vibration damping sheet according to the present embodiment.
FIG. 7 is a graph showing the relationship between the carbon material addition ratio and the vibration damping property in the vibration damping sheet according to the present embodiment.
FIG. 8 is a graph showing the relationship between the carbon material addition ratio and the deodorizing ability in the vibration damping sheet according to the present embodiment.
FIG. 9 is a schematic cross-sectional view showing a state in which a damping sheet is placed on the opening end of the container.
FIG. 10 is a schematic cross-sectional view showing a state in which the vibration damping sheet is heated and stretched and falls toward the inside of the container.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Floor panel 24 ... Damping sheet 26 ... Carbon material 27 ... Paint slag 28, 52 ... Crusher 38 ... Dehydrating device 42 ... Heat processing device 46 ... Heat source 56 ... Opening hole

Claims (1)

A carbonization step in which carbon material is produced by carbonizing the paint cake by carbonization,
A mixing step of adding the carbon material to a composition containing at least an asphalt material,
A molding step of molding the mixture;
A method for producing a vibration damping material, comprising:

Images