JP2003340913A - Molded ceiling for car and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To continuously, directly and integrally foam a surface material and hard urethane foam for a molded ceiling to provide the molded ceiling for a car without cutting out a foam ceiling from the hard urethane block foam for a ceiling, for a preliminarily manufactured molding ceiling and subsequently bonding the surface material to the foam ceiling using an adhesive. <P>SOLUTION: A plurality of surface materials are continuously delivered, and an open-cell hard urethane reaction solution is continuously supplied to the gaps between the surface materials in a sandwich state to coat the surface materials to form a polyurethane molded ceiling sheet to mold the same under heating and pressure into a ceiling shape. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a molded automobile ceiling having a surface material on the lower surface. More specifically, the present invention relates to a manufacturing method for continuously integrating a surface material and an open-cell rigid polyurethane foam reaction liquid.

[0002]

2. Description of the Related Art In recent years, the ceiling for automobiles is changing from a suspended ceiling to a molded ceiling, and in particular, it is changing to an integral type of a surface material and polyurethane foam having open-cell rigid. Molded ceilings of this type have a sandwich structure of facing material open cell rigid polyurethane foam-facing material. This type of polyurethane foam molded ceiling is a continuous foam rigid polyurethane foam cut out from a block foam-shaped continuous foam rigid polyurethane foam plate and a surface material after being integrated into a sandwich using an adhesive,
It manufactures molded ceilings for automobiles by hot press molding.
Since the open cell rigid polyurethane foam plate removes the skin from the block foam, the yield is about 50% and the cost is increased, and since the surface material and the foam body are bonded together, the productivity is low and the cost is increased. .
In addition, there is an environmental problem that the residual material from 50% yield becomes industrial waste.

[0003]

The object of the present invention is to continuously produce a polyurethane foam plate and a surface without cutting the polyurethane foam plate from the block foam and without adhering the surface material and the polyurethane foam plate with an adhesive. It is to provide a molded ceiling for an automobile that integrates materials. Another object is to eliminate the waste generated when cutting the polyurethane foam plate from the block foam. Another object is to eliminate the adhesive and the number of steps for adhering the cut polyurethane foam plate to the surface material.

[0004]

According to the present invention, a plurality of surface materials are continuously drawn out, and one or more surface materials that have been drawn out have a density of 15 to 50 kg / m ³ of open-cell rigid polyurethane foam reaction liquid ( Hereinafter referred to as urethane reaction liquid)
After coating, the remaining surface material is integrated with the urethane reaction liquid surface coated and sandwiched. Next, by foaming and curing, and continuously or discontinuously performing hot press molding at 70 ° C. or higher, the desired molded ceiling for automobiles can be continuously manufactured. Further, as another manufacturing method for solving the problem, a urethane foam reaction liquid having a density of 15 to 50 kg / m ³ is filled between a plurality of surface materials and integrated in a sandwich form, followed by foaming and curing, followed by continuous formation. The intended polyurethane molded ceiling for automobiles can be continuously produced by heating the steel sheet at 70 ° C. or more in a non-continuous manner.

Here, the rigid polyurethane foam used in the present invention needs to be an open cell rather than a closed cell. The open cell rate is preferably 70% or more, more preferably 90% (according to ASTM D2856-70).
The above is good. When the open cell ratio is 70% or less, it is necessary to increase the pressing pressure in the process of hot press molding into a ceiling shape, which is not preferable because large equipment is prepared. There is also a problem that the noise absorption performance is deteriorated and the noise outside the vehicle enters the inside of the vehicle. Further, the open cell rigid polyurethane foam density is preferably 15 to 50 kg / m ³ ,
If it is less than kg / m ³ , the rigidity of the ceiling material after molding is low, and the initial shape cannot be maintained for a long time. Again 5
If it is 0 kg / m ³ or more, it is not preferable because it has rigidity but its weight becomes heavy and the heat insulation performance for preventing heat from flowing in from the side of the automobile ceiling plate is deteriorated.

The surface material used in the present invention includes a surface material manufactured in advance as a completed surface material or a surface material finished as a completed surface material in the process of manufacturing a polyurethane molded ceiling. It is included in the range of. Examples of the finished surface material are glass fiber non-woven fabric, polypropylene non-woven fabric, fiber-impregnated polypropylene sheet (FRP) in which some fibers such as glass fiber or polypropylene fiber are projected, and roughened surface is added to the fiber fully-impregnated surface. Polypropylene sheet, polypropylene film surface raising sheet, polyethylene film surface raising sheet, cloth such as tricot, polyurethane film sheet, polyester film sheet, etc., but preferably glass fiber impregnated polypropylene sheet in which a part of glass fiber remains on the surface good. As an example of the surface material that will be the finished surface material in the process of manufacturing the polyurethane molded ceiling, a nonwoven fabric consisting of glass fiber and propylene fiber is continuously heated and press-molded before the application of the polyurethane reaction liquid to complete the glass fiber impregnation. There is a polypropylene sheet or the like, but the polypropylene sheet is not limited thereto.

The applied urethane reaction liquid foams to form an open-celled rigid polyurethane foam, and at the same time, adheres to the surface material to be integrated in a sandwich form. In order for the surface material to be bonded and integrated with the open-cell rigid polyurethane foam, it is preferable that the material itself has an adhesive property, such as a polyester film sheet, or that at least one surface of the surface material has a protruding surface. Particularly, in the case of a surface material sheet mainly composed of an olefin resin such as polypropylene or polyethylene, it basically does not adhere to the polyurethane resin. Therefore, it is necessary to impregnate a part of glass fibers or polypropylene fibers protruding from the surface material with the polyurethane reaction liquid, or to provide a rough surface on the surface.

In the present invention, the open-celled rigid polyurethane foam is integrated with the surface material in a sandwich form, foamed and cured, and the process proceeds to the next step. The polyurethane molded ceiling plate sandwiched by the foam-cured surface material is either continuously pressed by the hot press molding device that moves in conjunction with sandwiching in the next step or cut into a short length and moved to another step. Alternatively, they may be heat-press molded discontinuously. Specifically, it may be hot-press molded beside the production line, or may be transferred to another factory and then hot-press molded. In performing the present invention, heating press molding is performed on the shape of the ceiling, but the heating temperature is 70 ° C to 220 ° C.
The temperature range is preferably in the range of 90 ° C to 180 ° C. When the hot press molding temperature is 70 ° C. or lower, it takes several minutes to several tens of minutes for molding, and sharp molding is difficult, so that the product has low commercial value. In addition, the press mold temperature is 22
When the temperature is higher than 0 ° C, the molding time is several seconds, but the stable time width of the hot press molding is narrow, and it is not possible to stably obtain a molded ceiling having a constant shape. In the temperature range of 90 ° C. to 180 ° C., the heat press molding time can be set within the range of about 10 seconds to about 2 minutes and a product can be stably obtained.

In the present invention, the state of the urethane reaction liquid for applying the urethane reaction liquid to the surface material is not particularly limited, but the froth foaming state is preferable. The froth foaming state in the present invention refers to a state in which a part of the urethane reaction liquid is already foamed when it is applied to the surface material.

Conventional molded ceilings have a thickness of 4-6 mm. When carrying out the present invention, the polyurethane reaction liquid is applied extremely thinly in order to satisfy the density and foam thickness of the conventional foam. However, with such a coating amount, the gas required for foaming generated in the coating solution easily escapes to the outside of the system and is not utilized for foaming and is densified. Such a high-density rigid polyurethane foam is heavy and does not become an open-cell rigid urethane foam having a density of 15 to 50 kg / m ³ . In order to prevent the gas required for foaming to escape to the outside of the system even with a small coating amount, it is preferable to apply in the above-mentioned floss foaming state. The preferable froth foaming state means that it is foamed at the time of application, and the foaming rate is 5 to 80% (volume of bubble / volume of reaction solution including bubbles x 1).
00) is good. As a method for forming a floss foaming state, an organic solvent having a boiling point lower than the raw material temperature at the time of coating is mixed into the foaming machine, or a mechanical floss method in which gas is mechanically stirred and mixed in the middle of the raw material piping, or mixed into the foaming machine head. And the like. Examples of the mixed gas include CO ₂ , N ₂ , air and argon.

In the present invention, the method of applying the urethane reaction liquid to the surface material is a method of applying the urethane reaction liquid while traversing the width of the surface material while delaying the reactivity and uniformly using a reverse roll. Method of coating Method of applying uniform thickness by doctor knife method while traversing urethane reaction solution Method of applying while traversing using multiple spray guns or method of applying using coat hanger type die under specific conditions is there.

In the above-mentioned method, unlike the production of a general hard urethane board, the coating amount is very small in the present invention, so that a uniform foam height can be obtained between the portion coated by the traverse and the portion not coated. However, the thickness of the uncoated area tends to be thin. Further, in the above-mentioned method, even if the amount of catalyst is reduced, or even if a delaying catalyst is used, a low-molecular-weight polyol of rigid urethane foam is used, so that a reaction occurs at the time of mixing the polyisocyanate and a reaction occurs in the reverse roll. The liquid tends to solidify. Therefore, there are some restrictions on the raw materials used. Similar to the method described above, the reaction liquid tends to solidify on the doctor knife, and similarly, the raw materials used are partially limited. The above method does not solidify the reaction solution in the spray gun because it is immediately discharged even if the polyol-based raw material and the isocyanate-based raw material are mixed by the spray gun even if the rigid urethane foam-based low molecular weight polyol is used. . Therefore, it can be freely selected without considering the reactivity of the raw materials. However, the raw material loss tends to increase. The above-mentioned method uses a coat hanger type die under specific conditions, so even if a highly reactive polyol or polyamine compound is used, the urethane reaction solution at all points in the die is uniformly discharged in a short time. The inside of the die does not gel with the polyurethane reaction solution, and the raw materials can be freely selected.

The coat hanger type die under the specific conditions used in the present invention has a manifold opening angle of 120 to 150 degrees, and the ratio of the die volume excluding the manifold volume and the die lip volume to the manifold volume is 1: 0. .2
It is preferable to set the ratio of the die volume excluding the manifold volume to the manifold volume to be 1: 0.1 to 1: 0.7. Here, the manifold angle refers to θ in FIG. When the ratio of the die volume to the manifold excluding the manifold volume and the die lip volume in the die and the ratio of the die volume to the manifold excluding the manifold volume are outside the above range, the residence time at the center of the die is the average residence time. It reaches several times to several tens of times compared to the time,
The residence time on the side of the die reaches several times to several dozen times as long as the average residence time, and the raw material in the die is solidified. The urethane reaction solution is introduced from the raw material inlet at the center of the coat hanger die, but the manifold is designed so that the manifold cross-sectional area becomes smaller toward the die end.
By this setting, the discharge amount and the reaction solution retention time in the die are constant over the entire width of the coat hanger die.

Further, in using the present coat hanger type die under the specific conditions of the present invention, it is 3 with respect to the total raw material volume.
It is preferable to mix a gas of volume% (normal temperature, normal pressure) or more into the raw material. As a concrete mixing method, there is a method of installing a gas mixer with stirring blades between each polyurethane raw material piping line, a mixing head, or a raw material pump and a mixing head. An ultrafine cell can be obtained by mixing gas. As the type of gas, the gas used for forming the froth foaming state can be used as well.

In following the present invention, an open cell rigid polyurethane foam compounding formulation will be described. The preferred polyisocyanate used in the process of the present invention is a mixture of diphenylmethane diisocyanate and polyphenylpolymethylene polyisocyanate (generally crude MD).
(I) is good. However, the polyisocyanate is not limited to this. As the polyol used in the method of the present invention, there are polyether polyols having an OH value of 25 to 600 for producing a flexible or rigid polyurethane foam, or polyester polyols having an OH value of 56 to 500. As the low molecular weight cross-linking agent, ethylene glycol, propylene glycol, diethylene glycol, glycerin, 1,4 butanediol, triethanolamine, diethanolamine, etc. are used, and they are appropriately selected and used according to the desired physical properties of the foam. N-hexane, cyclohexane, and H ₂ which are commonly used as a foaming agent
Any blowing agent such as O or CO ₂ can be used, but water is preferable as an environmental measure. Water as a foaming agent is usually used in an amount of about 3 to 6% by weight based on all raw materials.

The polyurethane foam of the present invention is mainly composed of open cells. As a method for forming open cells, a known method may be used, for example, as an open cell agent, a liquid hydrocarbon such as polybutene, polybutadiene, polyisoprene, or a crosslinking agent such as low molecular weight glycerin, or 70 to 100% by weight of ethylene oxide graft. There are many methods such as low molecular weight polyol, but the method is not particularly limited. Published patents relating to the open-cell rigid polyurethane foam include JP-A-58-69219 and JP-A-4-3.
51621, JP-A-61-151222, JP-A-51-152
69596, JP-A-49-105899, JP-A-63-
89517, JP-A-57-212219, JP-A-51-
93995, JP-A-63-92630, JP-A-4-21.
1416 etc.

The silicon bubble stabilizer used in the present invention may be a generally used polydimethylsiloxane-polyoxyalkylene copolymer, which may be appropriately selected and used. As the catalyst used in the present invention, N, N'-trimethyl-N'-hydroxyethylenediamine, N, N, N ', N'tetramethylhexanediamine, N, N, N', N ", N, which are generally used, are used. A tertiary amine such as pentamethyldiethylenetriamine and an organic metal catalyst such as dibutyltin dilaurate are used, but a tertiary amine catalyst is preferable. In the present invention, other additives generally used in polyurethane foams can also be used, and flame retardants, inorganic fillers, pigments, antioxidants, ultraviolet absorbers and the like are used.

[0018]

Embodiments of the invention will be described with reference to the drawings, but the invention is not limited to the embodiments. Figure 1
FIG. 3 is a partially cutaway perspective view of a coat hanger type die used in the present invention. 2 is a partially cutaway plan view of the coat hanger die of FIG. FIG. 3 is a sectional view taken along the line AA ′ of FIG. In the main coat hanger type die 1 composed of two die-constituting plates 1a and 1b, a urethane reaction liquid in which a polyol component and a polyisocyanate component are mixed is introduced from a raw material inlet 3 and flows through a groove of a manifold 2 to form a manifold. Reach the edge. During this time, the urethane reaction liquid in the manifold partially flows out from the die land gap 10 to the die land 6. Reference numeral 4 denotes a pressure adjusting groove, which is not necessary for uniformizing the urethane reaction liquid whose amount and residence time are made uniform by the manifold 2 and the die land 6 in the width direction. The urethane reaction liquid that has passed through the pressure adjusting groove 4 reaches the die lip 8 and is then discharged from the die lip outlet 7 to be applied on the surface material with a uniform thickness. In the coat hanger type die of the present invention, the discharge amount and the residence time from the raw material introduction port to the die lip outlet 7 are basically uniform over the entire width of the die, but the die lip gap adjustment is performed to further improve the quantitative uniformity. Bolt 5 is attached for fine adjustment.

FIG. 4 is a process diagram showing a pre-process of the urethane reaction liquid introduced into the coat hanger type die of the present invention.
The tank is composed of a polyol-based raw material tank 11, a polyisocyanate-based raw material tank 12, a foaming agent and other raw material component tank 13, and an N ₂ gas tank 14 in addition.
Is installed. Polyol is a polyol tank 11
Is sent to the gas mixer 17 through the metering pump 15.
Further, the N ₂ gas is supplied from the N ₂ gas tank 14 to the gas flow meter 16
And is sent to the gas mixer 17. In the gas mixer 17, the stirring blade 21 is rotated by the motor 19, and the introduced N ₂ gas is dissolved in the polyol component in the gas mixer 17, but the undissolved N ₂ gas is fine bubbles. It becomes N ₂ gas and becomes partially foamed (floss foamed). The polyol-based component mixed with the gas is introduced into the next mixing head 18. Next, the polyisocyanate component is metered from the polyisocyanate tank 7 by the metering pump 15 and introduced into the mixing head 18. In addition, a tank 13 containing a foaming agent, a catalyst, a silicon surfactant, and the like is mixed and weighed through a pump 15 and introduced into a mixing head 18. In the mixing head 18, the stirring blade 22 is rotated by the motor 20 to uniformly mix the polyol component and other components, which are introduced into the next coat hanger die 1 and discharged from the die lip outlet 7 to be applied to the surface material. To be done. It is preferable that the discharged urethane reaction liquid is in a mechanically frothed state in which it is partially mechanically foamed.

FIG. 5 is a side view of equipment simulating the process of manufacturing a molded ceiling for an automobile using the coat hanger type die of the present invention. The urethane reaction liquid discharged from the coat hanger die 1 is continuously applied onto the lower surface material 35, and the upper surface material 32 is further stacked to form a sandwich. The urethane reaction liquid 30 is foamed in the foaming oven 26 to form a sandwich-shaped polyurethane molded ceiling plate 3
It becomes 1. The polyurethane molded ceiling plate 31 is sandwiched between the heat press molding dies 28 and 29 and continuously and consistently molded into a ceiling shape to manufacture a polyurethane molded ceiling 33 for automobiles. The polyurethane molded ceiling plate 31 is cut into a certain length with a cutter and discontinuously transferred to another process, and is similarly heat-press molded into a ceiling shape with heating dies 28 and 29. Can also be completed.

FIG. 6 is a side view of equipment simulating a process for continuously manufacturing a molded automobile ceiling by applying a urethane reaction liquid to a surface material using a spray gun. This process is the same as that of FIG. 5 except that the coat hanger die 1 of FIG.

According to the conventional method for manufacturing a ceiling material for automobiles, a polyurethane foam block is manufactured, and a polyurethane foam plate cut out at a yield of 50 to 60% from the block foam is bonded to a surface material with an adhesive. However, according to the present invention, it is possible to directly obtain the final product in a single step without a plurality of steps, and to improve the polyurethane foam yield to a high yield of 85 to 95%. It is possible to provide a method of manufacturing a molded ceiling having extremely high flexibility. At the same time, the cutting and laminating processes are deleted, and industrial waste is not generated.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a coat hanger type die of the present invention.

FIG. 2 is a partially cutaway plan view of a coat hanger type die of the present invention.

FIG. 3 A- of the coat hanger type die of FIG. 2 of the present invention
A'cross section

[Fig. 4] Process drawing of foaming machine

FIG. 5 is a side view of the equipment simulating the process of manufacturing the molded ceiling.

FIG. 6 is a side view of the equipment simulating the process of manufacturing another molded ceiling.

[Explanation of symbols]

1: Coat hanger type dies 1a, 1b of the present invention: Die component plate of the liquid separator of the present invention 2: Manifold 3: Urethane reaction solution inlet 4: Pressure adjusting groove 5: Die lip gap adjusting bolt 6: Die land 7: Die lip Outlet 8: Die lip 9: Die lip gap 10: Die land gap 11: Polyol-based raw material tank 12: Polyisocyanate-based raw material tank 13: Foaming agent and other raw material component tank 14: N ₂ gas tank 15: Pump 16: Flow meter 17: Gas mixing Machine 18: Mixing head 19: Motor 20: Motor 21: Stirring blade 22: Stirring blade 23: Lower surface material feeding roll 24: Belt conveyor driving roll 25: Upper surface material feeding roll 26: Foaming oven 27: Belt conveyor belt 28: Upper surface heating press molding die 29: Lower surface heating press molding die Mold 30: Coated open-cell rigid polyurethane foam reaction liquid 31: Polyurethane molded ceiling board 32: Top surface material 33: Automotive polyurethane molded ceiling 34: Spray gun 35: Bottom surface material

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) // B29K 75:00 B29K 75:00 105: 04 105: 04 B29L 9:00 B29L 9:00 31:58 31:58 F-term (reference) 3D023 BA01 BB03 BC00 BD01 BE05 BE31 4F204 AA42 AD05 AD08 AD24 AD35 AG03 AG20 AH26 EA03 EA04 EB01 EB02 EB13 EF01 EF05 EK02 EK04 EL17 EL19 EW02 AG03 MA21 A05A0542A03A05AH20 AA42L05A0342A03AH05 4F213 AA42 AC05 AD08 AG20 AH26 WA02 WA08 WA15 WA18 WA32 WA38 WA39 WA43 WA52 WA54 WA56 WA72 WA85 WA87 WB01 WC02 WE02 WE21 WF01 WF27 WF37 WK01 WK03 WW01 WW06 WW15 WW21 WW26

Claims (9)

[Claims] 1. A plurality of surface materials are continuously delivered, and a density of 15 to 15 is provided on the surface of one or more surface materials delivered.
After coating the open cell rigid polyurethane foam reaction liquid of 50 kg / m ³ , other remaining surface materials are placed and integrated in a sandwich form, or a density of 15 to 50 kg / m ³ is provided between a plurality of surface materials. A method for producing a molded ceiling for an automobile, in which a reaction liquid containing open-celled rigid polyurethane foam is filled and integrated in a sandwich form, followed by foaming and curing, followed by continuous or discontinuous heat press molding at 70 ° C or higher. 2. The method for producing a molded ceiling for an automobile according to claim 1, wherein the open-cell rigid polyurethane foam reaction liquid is in a froth foamed state in which a part of the reaction solution is foamed. 3. The method for producing a molded ceiling for an automobile according to claim 1, wherein the method for applying the open cell rigid polyurethane foam reaction liquid to the surface material is a spray method. 4. A method of applying an open-cell rigid polyurethane foam reaction solution to the surface material uses a coat hanger type die, and further, 3% by volume (at room temperature,
The method for producing a molded ceiling for an automobile according to any one of claims 1 and 2, wherein a gas having an atmospheric pressure or higher is mixed in the raw material. 5. The manifold opening angle of the coat hanger die is 120 to 150 degrees, and the ratio of the die inner volume excluding the manifold volume and the die lip volume to the manifold volume is 1: 0.2 to 1. : 0.7, and the ratio of the die internal volume excluding the manifold volume to the manifold volume is 1: 0.1 to 1: 0.7, wherein the molded ceiling for automobiles is continuously produced. 6. The method for manufacturing a molded ceiling for an automobile according to claim 1, wherein the surface material is a sheet having protrusions on the surface. 7. The method for producing a molded ceiling for an automobile according to claim 6, wherein the sheet having the protrusions is a glass fiber-impregnated polypropylene sheet having a part of glass fibers protruding on the surface. 8. A molded ceiling for an automobile, which has surface materials on an upper surface and a lower surface of an open-cell rigid polyurethane foam, and is directly integrally molded without using an adhesive when laminating them. 9. The molded ceiling for an automobile according to claim 8, wherein the surface material is a glass fiber-impregnated polypropylene sheet.