JP2940718B2 - Rigid structure for vehicle panels - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention is, floor panel of a vehicle or the like, dash panel, wheel house, the ceiling panel or the like (hereinafter
Below, it is described as "vehicle panel". )
More specifically, the rigid structure used has good workability, is excellent in rigidity over a wide temperature range, and completely follows an uneven panel plate by heating, and each constituent layer is integrated. Vehicle panel suitable for manufacturing a panel structure
The present invention relates to a rigid structure for use .

[0002]

2. Description of the Related Art It is desired to improve the quality of a wide substrate surface such as a vehicle panel by increasing rigidity from the viewpoint of vibration control or improvement of firmness. This will be described in more detail. 2. Description of the Related Art In automobiles, reduction in weight is desired from the viewpoint of environmental protection such as carbon dioxide emission regulation and resource protection. In this regard, measures have been taken to reduce the thickness of the material, reduce the number of structural members, and the like. However, reducing the weight by such a method reduces the strength. Due to the decrease in strength, the rigidity of the surface becomes insufficient, and problems such as insufficient rigidity as a member occur.
In order to solve this problem, Japanese Utility Model Laid-Open No. 55-101659
In Japanese Patent Application Laid-Open Publication No. H11-264, a method using a door panel reinforcing material is proposed. However, this method has a problem that not only sufficient rigidity cannot be obtained, but also a large amount of work for manual attachment, resulting in extremely difficult workability.

[0003] Under such circumstances, the present inventors have made a composition comprising a vinyl chloride resin for a paste , a plasticizer, a foaming agent, etc., contain a liquid epoxy resin and a heat-activated curing agent, and applied it as a plastisol. Then, this is attached to a necessary part as a semi-gelling sheet, and a rigid resin sheet is placed thereon , and a method of heating and foaming is proposed (Japanese Patent Application No. 2-75494). Has gained structure. ADVANTAGE OF THE INVENTION According to this invention, while attaching operation | movement became easy, the rigidity was high and the vehicle panel with firm feeling came to be obtained.

[0004]

However, since the method contains a vinyl chloride resin in the composition, thermal decomposition of the resin occurs at a high temperature such as an electrodeposition coating step in an automobile production line. There was a problem that there was a possibility. Under such circumstances, the present invention can provide a vehicle panel that is lightweight and imparts high rigidity, has good heat resistance, and has a composition that can withstand, for example, an electrodeposition coating process. It is an object to provide a rigid structure for use.

[0005]

According to the present invention, a synthetic tree is provided.
Upper layer sheet (2) made of a fat sheet and foamable thermosetting resin
Of a two-layer structure consisting of a lower sheet (1) consisting of
A layer member, the lower layer sheet, (A) in a molecule 1
100 parts by weight of an epoxy resin having at least two epoxy groups, (B) 0.5 parts by weight of a co-reactive curing agent for an epoxy resin
Beyond less than 20 parts by weight, (C) decomposition gas generation temperature 1
20 parts by weight exceeding 0.5 parts by weight of blowing agent at 00 to 220 ° C
Less than 5 parts by weight , (D) more than 0.05 parts by weight of surfactant
Less than an amount unit, and (E) is insoluble in room temperature the epoxy resin, and a rubber elastic body miscible dispersion with the epoxy resin at a temperature of 80 to 150 ° C., or room temperature free of halogen is insoluble in the epoxy resin Average particle size 150μm
By containing at least one selected from the following powdery thermoplastic resins in an amount of more than 10 parts by weight and less than 200 parts by weight and heating at a temperature not higher than the decomposition gas generation temperature of the foaming agent (C): That it is a semi-gelled sheet
A rigid structure for a vehicle panel is provided.

[0006] Various path of the vehicle the structure according to the present invention
A vehicle panel that can improve rigidity in a range where the weight increase of the vehicle is small by being fused and integrated with the flannel plate.
Etc. can be manufactured . In addition, this type of structure
Is an uneven panel due to heat treatment in the drying process such as painting.
With close contact to Le plate, each of the reaction, foaming, it is necessary to fuse completes, yet but in which less material decrease in the physical properties required as the preferred properties even at relatively high temperatures, the according to the present invention The structure correctly meets these requirements.

Hereinafter, each constituent layer according to the present invention will be described. The lower layer sheet (1) used in the present invention imparts a function as a spacer. Preferred properties of the spacer in a vehicle panel are light weight, high rigidity, and little change in physical properties due to temperature change. And is adhered and fixed to the uneven panel plate in the coating and drying process.
In this step, there is a high magnification foaming action. Take
A composition for imparting a function as a spacer (hereinafter, referred to as a “spacer”)
Pacer composition " . )) , The epoxy resin used as the component (A) is a liquid epoxy resin containing one or more epoxy groups in the molecule, such as bisphenol A , bisphenol F or resorcinol. Glycidyl ether , polyglycidyl ether of phenol novolak resin or cresol novolak resin, glycidyl ether of hydrogenated bisphenol A , glycidylamine type , linear aliphatic epoxide type , phthalic acid , glycidyl ether of hexahydrophthalic acid or tetrahydrophthalic acid For example, the preferred epoxy equivalent is 100 to 30.
0. These epoxy resins may be used alone or in combination of two or more. In order to impart toughness to the obtained foam, ethylene oxide or propylene oxide-added phenolic epoxy resin is used. And a flexible epoxy resin such as a dimer acid type epoxy resin or an epoxy-modified NBR.

In the above spacer composition , a co-reactive curing agent for an epoxy resin is used as the component (B).
The curing agent preferably has an exothermic peak temperature in the range of 100 to 200 ° C. in combination with the epoxy resin,
Such as, for example, dicyandiamide ,
4,4, '-diaminodiphenylsulfone , 2-n-
Imidazole derivatives such as heptadecyl imidazole, isophthalic dihydrazide, N, N-dialkylthiourea derivatives, acid anhydrides such as tetrahydrophthalic anhydride, isophorone diamine, m-phenylenediamine;
N-aminoethylpiperazine , fluoboric acid complex compound, trisdimethylaminomethylphenol and the like can be mentioned. One of these curing agents may be used,
Two or more kinds may be used in combination, and the amount added is more than 0.5 part by weight and less than 20 parts by weight per 100 parts by weight of the epoxy resin of the component (A). If the amount is less than 0.5 part by weight, the curing is insufficient and the rigidity of the foam is insufficient. If it exceeds 20 parts by weight, the rigidity of the foam is not improved for the amount, which is economically disadvantageous. Becomes The curing temperature here refers to a temperature of a medium at which heat generated by curing when a mixture of an epoxy resin and a curing agent at room temperature is heated by an oil bath, a heater, or the like has a peak. Further, the preferable combination and amount of the epoxy resin and the curing agent according to the heating conditions can be easily determined by conducting a test in advance. In the present invention, together with the curing agent of the component (B), if necessary, a curing accelerator such as an alcohol-based , phenol-based , mercaptan-based , dimethylurea-based , aliphatic-based , imidazole-based , monuron , or chlorotoluene may be used . Etc. can be used.

In the spacer composition, a foaming agent having a decomposition gas generation temperature of 100 to 220 ° C. is used as the component (C). Such foaming agents include organic foaming agents ,
Inorganic foaming agents , high temperature expansion type capsules and the like can be used. If the decomposition gas generation temperature is 100 ° C. or lower, foaming starts during processing of a semi-gelled sheet described later, or resin is insufficiently melted during foaming in a heating furnace to cause outgassing, and the foaming ratio is large. Or it is difficult to obtain a uniform foam. Further, when the temperature exceeds 220 ° C., the processing temperature of the composition becomes high, and the resin is deteriorated, so that it is difficult to obtain a foam of good quality. Such organic foaming agents include, for example, azodicarbonamide , p-
Toluenesulfonylhydrazide , dinitrosopentamethylenetetramine , 4,4′-oxybisbenzenesulfonylhydrazide and the like can be mentioned. The decomposition temperature of these organic blowing agents can be easily adjusted by adding urea , a zinc compound, a lead compound, and the like. Also,
Examples of the inorganic foaming agent include sodium hydrogencarbonate and potassium borohydride , and examples of the high-temperature expansion type microcapsules include those obtained by encapsulating a low-boiling hydrocarbon with a vinylidene chloride resin.

In the present invention, any of the above-mentioned organic foaming agents , inorganic foaming agents , and high-temperature-expandable microcapsules can be used, but from the viewpoints of expansion ratio, economic efficiency, etc., organic foaming agents are suitable. . These foaming agents may be used alone or in combination of two or more.
The addition amount is selected in the range of more than 0.5 parts by weight and less than 15 parts by weight per 100 parts by weight of the epoxy resin (A). If the amount is less than 0.5 part by weight, the foaming becomes insufficient. If the amount exceeds 15 parts by weight, the expansion ratio is not improved in spite of the amount, and in many cases, problems such as roughening of the foamed cells occur. In order for these foam cells to obtain a dense foam having a uniform cell diameter and a rigid cell membrane, it is advantageous that the particles of the blowing agent have a small particle size, for example, 0.1 to 0. In order to obtain a foam having a cell diameter of about 0.6 mm, preferably about 0.3 mm, the particle diameter should be 20 μm or less,
Preferably, it is 10 μm or less and uniform. In the present invention, a foaming accelerator can be used, if necessary, together with the foaming agent. Examples of the foaming accelerator include calcium stearate , barium stearate , sodium and potassium compounds, and urea.

In the spacer composition, a surfactant is used as the component (D). This surfactant has a role of improving the structure of the foam cell (hereinafter, referred to as “cell structure”). The surfactant, such as sodium lauryl sulfate, alkyl sulfate ester salts such as sodium myristyl sulfate, sodium dodecyl benzene sulfonate, alkyl aryl sulfonates such as potassium dodecyl benzene sulfonate, sodium dioctyl sulfosuccinic acid, sulfosuccinic acid ester salts such as dihexyl sulfoxylate sodium succinate, ammonium lauryl acid, fatty acid salts such as potassium stearate, polyoxyethylene aryl sulfates, can be exemplified preferably anionic surfactants such as rosin acid salt. Furthermore , nonionic surfactants such as sorbitan esters such as sorbitan monooleate and polyoxyethylene sorbitan monostearate, polyoxyethylene ethers, polyoxyethylene alkyl phenyl ethers and polyoxyethylene alkyl esters And cationic surfactants such as cetylpyridinium chloride and cetyltrimethylammonium bromide. These surfactants may be used alone or in combination of two or more. The amount of addition is the same as that of the epoxy resin (A).
It is selected in a range of more than 0.05 part by weight and less than 5 parts by weight, preferably 0.2 to 3 parts by weight, per 100 parts by weight of the resin . The 0.05 parts by weight or less, not obtained serves to the cell structure favorable, even in 3 parts by weight or more, originating in the split
The stability of the foam cell is not improved, and in some cases, it may cause coloring due to decomposition during heating. As a method for adding the surfactant, in the case of a rubber elastic material or a powdery thermoplastic resin used as the component (E), it is advantageous to spray and uniformly dry-adsorb in advance and use it.

The spacer composition comprises (E) insoluble in the epoxy resin (A) at room temperature, and
A rubber elastic material miscible and dispersible with the epoxy resin at a temperature of 0 to 150 ° C. or insoluble in the epoxy resin at room temperature ;
Halogen-free powder heat with an average particle size of 150 μm or less
At least one selected from plastic resins
You. In this case, not only a solid but also a viscous liquid can be used as the rubber elastic body. On the other hand, it is necessary to use a thermoplastic resin composition having an average particle diameter of 150 μm or less as a powder. When the composition is heated to 150 ° C. or higher, the rubber elastic body or the thermoplastic resin is melted to form a homogeneous affinity with the epoxy resin (A), and the melt viscosity of the composition is maintained stably. Things are desirable. Such materials include rubber elastic materials such as chloroprene rubber , butadiene-acrylonitrile rubber , carboxyl-modified butadiene-acrylonitrile rubber , epoxy-modified butadiene-acrylonitrile rubber , butadiene rubber , isoprene rubber, ethylene-vinyl acetate copolymer, and polyphenylene. Ether , ethylene-vinyl alcohol copolymer ,
Acrylonitrile-styrene copolymer , polyamide , polyvinyl butyral , polyvinyl acetal , polymethyl methacrylate , acrylonitrile-butadiene-styrene copolymer , methyl methacrylate-butadiene-
Styrene copolymers , polystyrene and the like can be mentioned. These may be used alone or in combination of two or more. The component (E) has a function of adjusting the melt viscosity of the spacer composition and a function of improving the toughness of the obtained foam. The amount of the component (E) added is more than 10 parts by weight and not more than 200 parts by weight per 100 parts by weight of the liquid epoxy resin of the component (A).
It is chosen in the full range. Although it depends on the type of the rubber elastic body or the thermoplastic resin containing no halogen, it does not have the function of adjusting the melt viscosity or the function of improving the toughness of the foam at 10 parts by weight or less. Conversely, at 200 parts by weight or more, This also depends on the type of rubber elastic body or thermoplastic resin,
Inconvenience that the expansion ratio of the foam does not improve or the rigidity of the foam lowers occurs.

In the above spacer composition , (A)
It is important to balance the affinity between the epoxy resin as the component and the rubber elastic body or the thermoplastic resin as the component (E).
It is necessary to appropriately select the type , molecular weight , particle size , addition amount and the like of the components. In particular, regarding the balance of the affinity, a system in which the polymers are completely compatible with each other during melting is not preferable, and it is desirable that the polymers are in a stable dispersion-mixing state. Therefore, depending on the combination of polymers, it is desirable to adjust the affinity of the polymer tube by adding a plasticizer to increase the affinity for each other. The plasticizer also has a function of adjusting the melt viscosity. Examples of the plasticizer include phthalate esters such as dioctyl phthalate and dibutyl phthalate, phosphate esters such as tricresyl phosphate, and dioctyl adipate. Fatty acid esters, furthermore, adipic acid condensate of ethylene glycol,
Conventionally known compounds such as trimellitic acid ester, glycolic acid ester, chlorinated paraffin, and alkylbenzene can be used.

[0014]Also,Facilitates initial mixing or filling
Epoxy, if necessary, for the purpose of increasing the amount of
A diluent for resin may be added. As this diluent
Is, for example, butyl glycidyl ether,Allyl glycidi
Ruether,Phenyl glycidyl ether,Cresorg
Ricidyl ether,Glycidyl ether persatic acid
And dibutyl phthalate,Dioctyl
Phthalate,Butyl benzyl phthalate,Tricresyl
Phosphate,Acetyl tributyl citrate
Le,Aromatic process oil,Pine oil,
2,2,4-trimethyl-1,3-pentadiol iso
Non-reactive diluents such as butyrate can be mentioned.
furtherAdjustment of coating properties such as processability and viscosity, and low cost
Thixotropic as necessary for the purpose of increasing the amount to reduce
A tropic agent or a filler may be added, and
May be added. As the thixotropic agent, for example,
Silicic acid such as silicic anhydride or hydrous silicic acid, organic bentona
Bentonites such as pits, asbestos such as Silodex
And organic systems such as dibenzylidene sorbitol.
Can be As the filler, for example, calcium carbonate,
Mica,talc,Kaolin clay,Celite,Asbes
G,Perlite,Barita,silica,Quartz sand,Scaly black
lead,Dolomite limestone,plaster,Aluminum powder
I can do it.

[0015]The above spacer compositionIs the above (A),
(B),(C),Indispensable components of (D) and (E)
Prescribe the various additive components used as desired
Quantity, for example, planetary mixer,Kneader,Low
Le,Henschel mixer etc.Prepare.in this way
do itThe prepared spacer compositionIs included in it
Melt viscosity at the decomposition gas generation temperature of the blowing agent is 2.5
× 10³~ 5 × 10⁴dPa. preferably in the range of s
Good. When the melt viscosity deviates from the above range, the appearance becomes
Good, expansion ratio 5 times or more and average cell diameter 0.5 m
m or less, it is difficult to obtain a preferable foam. In addition,
ClearThe lower sheet (1) in the vehicle panel rigid structure is
Semi-gelled sheetUsed for That is,
The abovePreparedPre-compose the composition below the decomposition temperature of the blowing agent
Formed into a sheet at a temperature ofUpper sheet
(2)After laminating, the next heating step, for example, paint drying
In the process, foam at 120 ° C to 200 ° C
In addition, it is cured by the crosslinking of the epoxy resin. Or
KaruruLower sheet (1)Foaming ratio of 2 to 30 times, preferred
It is 5 to 10 times. If the expansion ratio is 2 times or less,
Although it can of course function as a pacer,
From the point of view, it is not the purpose of the present invention, but 30 times or more
If the foaming ratio is too low, the strength of the foam cell is insufficient and the vehicle is used.
Some parts may have a problem in durability. Ma
The thickness of the lower sheet (1) after foaming is 1 to 50.
mm, preferably 3 to 30 mm. 1 mm or less
In this case, it cannot function effectively as a spacer and
0 mm or more is the object of the present inventionVehicle panel applications
In the case that the space inside the car becomes narrow and it becomes impractical
In the heating process such as the drying process, uniform foaming properties are obtained.
Can not be.

The upper layer sheet (2) in the present invention is elastic.
A panel made of a rigid synthetic resin sheet, having a high elastic modulus, excellent durability, light weight, and unevenness due to heating in the coating and drying process for this type of vehicle.
It is necessary to consider the applicability to the vehicle panel such as the ability to follow the board and the required quality. As a desirable material satisfying such conditions, a thermoplastic resin sheet containing a tackifier resin such as a rosin resin , a terpene resin , an aliphatic petroleum resin , an alkylphenol-acetylene resin , a xylene resin , and a cumarone indene resin. And the like. Also,
Rubber such as tadiene rubber and styrene-butadiene rubber
Prepared by adding a large amount of vulcanizing agent to this as a base polymer
Of high hardness obtained by vulcanizing a cured thermoset plastic sheet
Vulcanized molded sheets and the like can also be used. Also, upper sheet
Although the thickness of (2) is not particularly limited, the thickness of the sheet formed on the panel plate of the vehicle is usually about 0.5 to 3 mm from the same viewpoint as the lower sheet (1). Used in. Uses rigid structure for vehicle panel of the present invention
The method of manufacturing vehicle panels by
(1) and each layer of the upper sheet (2) are individually
Placed on a metal plate and laminated, and heated ( paint
The flannel plate / lower layer sheet (1) / upper layer sheet (2)) may be fused and integrated with each other and foamed, and at the same time, may follow irregularities of a panel plate or the like, or may have two layers each. May be fused to the panel plate in a heating step such as a coating and drying step, and may be caused to follow foaming and irregularities of the panel plate.

[0017]

The rigid structure for a vehicle panel according to the present invention.
Is placed on a panel plate such as a vehicle ceiling panel or a door panel , and the lower sheet is foamed by heating .
Between the upper sheet (2) and the lower sheet (1) and the lower sheet
It is possible to firmly fix the space between the panel (1) and the panel plate and follow the uneven shape of the panel plate . Such a structure
Are the structures with a good spacer features thermostable a rigid with a dense cell structure of the expansion ratio in the lower layer sheet (1), the vehicle panel not only exhibits high stiffness over a wide temperature range The structure imparts rigidity and has excellent heat insulating properties.

[0018]

The present invention will be described below with reference to examples and comparative examples. The materials used for the test and the test method are as follows. I. Test material Vibrating substrate: 0.8 mm thick steel sheet Lower layer sheet (1) (spacer sheet) After mixing the epoxy resin composition with the compounding ratio shown in the following Table 20 using a Hobart mixer for 20 minutes, a predetermined sheet was formed on release paper. Was applied. This was heated at 120 ° C. for 100 seconds to produce a semi-gelled sheet.

[0019]

[Table 1]

The upper layer sheet (2) Table melt 2 in a thermoplastic composition compounding ratio shown in an autoclave and heated to 200 ° C., were mixed, and the resulting mixture was adjusted to a predetermined by hot pressing thickness . (Material code -F)

[0021]

[Table 2]

A thermosetting composition having a compounding ratio shown in Table 3 was kneaded with a roll and formed into a sheet having a predetermined thickness.

[0023]

[Table 3]

II. Test method Each of the lower sheet (1) and the upper sheet (2) was 15 ×
A structure was prepared in combination with a steel plate having a thickness of 300 mm and a thickness of 0.8 mm, and the rigidity ratio of each structure was measured at 20 , 40 , and 60 ° C. Lamination and foaming of each layer were performed by placing each layer on a steel plate and then performing a heat treatment in an oven at 150 ° C. for 30 minutes. The rigidity ratio was calculated from the moving frequency of the resonance point of the mechanical impedance by the following equation 1, and the rigidity ratio at 200 Hz was determined by interpolation. The measurement frequency is 1 to
1000 Hz.

[0025]

Stiffness ratio = (f ₀ / f) ² · {m ₁ + m ₂ ) / m ₁ }

Where f₀IsLower sheet (1), upper sheet
(2)One resonance frequency where is bonded to steel plate,f
Is the resonance frequency of the steel alone, m₁Is the surface of the steel sheet alone
Density, m₂IsLower sheet (1), upper sheet (2)Face
Density. In addition, the ability to follow irregular shapes is as described above.Underlayer
Seat (1),Upper sheet (2)20m each material
m, cut out to a length of 250 mm, and FIG.
(B) The height of the wave is 7.8 mm in the uneven shape shown in the side view.
Heating test in an oven on a steel plate so as to be orthogonal to the wave shape
An experiment was conducted to observe the followability. Heating conditions are bonding
It is the same as the case. Judgment is close without gap
Things are "○",Some gaps remain, but there is no problem in use
“の も の” for level,Gap remains and problems in use remainAlso
ofIndicates “×”. In addition, the uniformity of the foam cell is
By observing the “◎”,“○”,“△”,
Classification into four levels of “x” and expansion ratio
A measurement was made. According to these examples of conformability and foaming properties,
Table 4 shows the results, and Table 5 shows the results of the comparative example. Table 4
As shown in FIG.vehicle
Rigid structure for panelIs foaming,rigidity,No need to follow irregularities
While these are also good, in the comparative example shown in Table 5,
The structures of Comparative Examples 1 and 2 were remarkably inferior in foaming property,
3 and the structure are significantly less rigid.

[0027]

[Table 4]

[0028]

[Table 5]

[Brief description of the drawings]

FIG. 1 is a front view and a side view of a steel plate used for a followability test.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification symbol FI // C08L 63:00 (72) Inventor Seiki Yada 1-2-1 Yoko, Kawasaki-ku, Kawasaki-shi, Kanagawa Research of ZEON Corporation Inside the Development Center (72) Inventor Toshio Nagase 1-2-1, Yoko, Kawasaki-ku, Kawasaki-shi, Kanagawa Japan Zeon Co., Ltd. Inside the R & D Center (72) Inventor Hiroshi Kagoshima 1-chome, Yakko, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture No. 2 In the Research & Development Center of Zeon Corporation (56) References JP-A-61-154840 (JP, A) JP-A-2-248248 (JP, A) JP-A-62-231741 (JP, A) JP-A-62-251131 (JP, A) JP-A-4-73139 (JP, A) JP-A-4-73137 (JP, A) JP-B-60-26417 (JP, B2) (58) Field (Int.Cl. ⁶ , DB name) B32B 1/00-35/00 B60R 13/00-13/10 C08J 9/00-9/42

Claims (1)

(57) [Claims] (1)Synthetic resin sheetUpper layer sheet consisting of
(2) andThe lower sheet (1) made of foaming thermosetting resin
A two-layer laminate comprising:The lower layer sea
Has (A) one or more epoxy groups in one molecule
100 parts by weight of epoxy resin, (B) Kyocion for epoxy resin
Responsive curing agentMore than 0.5 parts by weight and less than 20 parts by weight,
(C) a foaming agent having a decomposition gas generation temperature of 100 to 220 ° C.
More than 0.5 parts by weight and less than 20 parts by weight, (D) surface activity
AgentMore than 0.05 parts by weight and less than 5 parts by weightAnd room (E)
Insoluble in the epoxy resin at temperature,And 80-150 ° C
Rubber elasticity miscible with the epoxy resin at temperature
Insoluble in the epoxy resin at room temperature or at room temperature
Powdered thermoplastic resin with no average particle diameter of 150 μm or less
At least one selected fromOver 10 parts by weight
Less than 200 parts by weightDecomposition of the foaming agent (C)
By heating at a temperature below the gas generation temperatureSemi gel
Rigidity for vehicle panels characterized in that it is a structured seat
Sex structure.