JP2002121477A - Sound-proof coating composition for vehicle and sound- proof coating structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound-proof coating composition which is used for vehicles, can reduce the damage of a vehicle coating due to the splashing of stones on the travel of the vehicle similarly to the cases of conventional coating compositions, further gives an excellent finished appearance, reduces sound due to the strike of the stone on the travel, and does not give unpleasantness to a crew, and to provide a sound-proof coating structure. SOLUTION: This sound-proof coating composition for vehicles, characterized by comprising (A) 100 pts.wt. of an acrylic polyol, (B) 60 to 300 pts.wt. of an isocyanate compound, (C) 100 to 700 pts.wt. of an inorganic filler, and (D) 3.0 to 50 pts.wt. of an additive. The sound-proof coated structure for vehicles, characterized by laminating a 0.1 to 1.0 mm-thick coating film comprising the sound-proof coating composition to an electrodeposition-coated site on the under- floor side of an automotive body or on the outside face of a side sill portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soundproof paint composition and a soundproof paint structure for a vehicle, and more particularly, to a rock jump on a lower surface of a floor of a vehicle body and an outer surface of a side sill portion when the vehicle is running. The present invention relates to a soundproof paint composition for vehicles and a soundproof paint structure for vehicles, which are useful for reducing sounds such as abnormal noise, noise, and noise due to (chipping).

[0002]

2. Description of the Related Art Conventionally, as a polyester undercoat, for example, "Tocalic # 8505" manufactured by Tokyo Chemical Paint Co., Ltd. and "Sundyne" manufactured by Asahi Rubber Co., Ltd. # 2196 "and the like, which are used as shown in FIGS. FIG. 1 is a side view showing an example of an automobile, and reference numerals indicate outer side surfaces of a side sill portion. FIG.
1 is an enlarged cross-sectional view showing a coating configuration on the outside of the side sill portion in a cross-sectional view taken in the direction of the arrow in FIG. 1, the reference numeral denotes a body panel, and denotes an electrodeposition coating. The coating is formed into a coating film through a baking process. Reference numeral denotes an undercoat which is usually applied with a thickness of 50 to 200 μm for the purpose of reducing paint damage caused by bouncing stones during running of the vehicle. Furthermore, is a middle coat or a top coat, and is formed into a coating film through a baking process. For the same purpose as above, for example, "Tokasol # 900" manufactured by Tokyo Chemical Co., Ltd. is also used as a polyvinyl-based undercoat.

[0003]

However, such an undercoat which has been conventionally used can reduce the paint damage caused by the bouncing stones during running of the vehicle, but does not reduce the sound caused by the bouncing stones on the vehicle body. Because of this, the noise caused by the rock hit during driving was loud, giving the occupants discomfort. As a countermeasure against this, the conventional paints
Attempts have been made to reduce the sound due to stone jumps by applying a thick coating by using a single coat, or by using a coating composition for thick coating, and in any case, it is possible to reduce the sound due to stone jumps on the vehicle body However, there is a problem that productivity is greatly reduced by coating twice, and finish appearance is deteriorated by coating thickly.

The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to reduce paint damage caused by rock jumps during vehicle running as in the prior art, and to further improve the finish. An object of the present invention is to provide a soundproof paint composition and a soundproof paint structure for a vehicle which are excellent in appearance and generate little noise due to rock contact during running, and do not cause discomfort to occupants.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, the use of a specific isocyanate compound, acrylic polyol, or the like at a predetermined compounding ratio has led to the achievement of the above object. They have found that this can be achieved and have completed the present invention.

That is, the soundproof coating composition for vehicles of the present invention comprises:
(A) 100 parts by weight of acrylic polyol, (B)
60 to 300 parts by weight of an isocyanate compound, (C) 100 to 700 parts by weight of an inorganic filler, and (D) an additive of 3.0 to 300 parts by weight.
It is characterized by containing 50 parts by weight.

Further, another soundproof coating composition for a vehicle according to the present invention comprises: (A) 100 parts by weight of an acrylic polyol,
(B) 60 to 300 parts by weight of an isocyanate compound,
It is characterized by being obtained by blending (C) 100 to 700 parts by weight of an inorganic filler and (D) 3.0 to 50 parts by weight of an additive.

Further, the preferred form of the soundproof coating composition for vehicles according to the present invention is (B) hexamethylene diisocyanate as an isocyanate compound, (C) a mixture of calcium carbonate, talc and calcium silicate as an inorganic filler,
(D) Dibutyltin dilaurate is selected as an additive.

Further, the soundproof coating structure for a vehicle according to the present invention has a film thickness of 0.1 to 1.
It is characterized in that a coating film of 0 mm is laminated on a portion to be coated of a vehicle.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The soundproof coating composition for vehicles of the present invention will be described in detail below. In addition, in this specification, "%" shows a mass percentage unless otherwise specified. As described above, the soundproofing coating composition for vehicles of the present invention comprises, as essential components, four components (raw components) of (A) an acrylic polyol, (B) an isocyanate compound, (C) an inorganic filler, and (D) an additive. I do.

First, the acrylic polyol as the component (A) is not particularly limited, but an acrylic polyol having 15 to 150, preferably 20 to 80, hydroxyl groups in one molecule is used. This coating composition employs a urethane-based material in order to have a sound-reducing characteristic and to maintain the chipping resistance, which is the original purpose of the undercoat, in order to sufficiently cause the urethane reaction to generate this. Requires 15 or more hydroxyl groups in one molecule of acrylic polyol. When the number of hydroxyl groups is less than 15, the reaction becomes insufficient and the soundproofing performance and the chipping resistance cannot be maintained. Further, if the amount of the reaction component is small, the connection of the coating material itself is weak and the coating film becomes brittle, which may cause cracks and poor adhesion during drying. On the other hand, as the number of hydroxyl groups increases, the amount of the isocyanate compound added must be increased. However, when the number of hydroxyl groups exceeds 150, a part of the isocyanate compound mixed in a large amount reacts with moisture in the outside air to form urea bond. Is formed, and a high hardness coating film is formed, and the chipping resistance may be reduced.

As a method for producing an acrylic polyol,
Examples thereof include a method of copolymerizing an appropriate amount of hydroxyalkyl methacrylate with a polymerizable monomer such as methacrylate. Specifically, in addition to acrylamide and styrene ethyl acrylate, in combination with acrylic acid ester, methacrylic acid ester, vinyl ketone, acrylonitrile, etc., solution polymerization is usually performed in an atmosphere of an inert gas such as nitrogen or carbon dioxide gas. It is manufactured by

The isocyanate compound (B) is an organic compound having two or more isocyanate groups in one molecule, which is used as a curing agent for the coating composition of the present invention. Is a compound having an isocyanate group reactive to a hydroxyl group of an acrylic polyol. Examples of such isocyanate compounds include:
Examples thereof include ordinary aromatic and aliphatic ones.For example, tolylene diisocyanate, hexamethylene diisocyanate, 4,4-diphenylmethane diisocyanate, liquid-modified diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate, xylyl diisocyanate, cyclohexyl diisocyanate, Cyclohexane phenylenediisocyanate, naphthalene-
1,5-diisocyanate, isopropylbenzene-
Examples include 2,4-diisocyanate, and addition products of polypropylene glycol and tolylene diisocyanate. In the present invention, these isocyanate compounds may be used alone or in combination of two or more.

The compounding amount of the (B) isocyanate compound is as follows:
(A) 60 to 3 parts by weight per 100 parts by weight of acrylic polyol
The amount is preferably 00 parts by weight, and more preferably 70 to 200 parts by weight. When the (B) isocyanate compound is less than 60 parts by weight, the curing is poor due to insufficient reaction,
Chipping sound performance and chipping resistance are not sufficient. On the other hand, if it exceeds 300 parts by weight, the curing is accelerated too much, so that the effect of reducing the chipping noise cannot be obtained.
This leads to a decrease in adhesion to the substrate (part to be coated).

The blocking agent for the isocyanate includes malonic diester as an active methylene compound,
Acetoacetate and acetylacetone, acetoxime, ketoxime, methylethylketoxime and butanone oxime as oxime compounds, phenol and cresol as phenol compounds, 2-methylimidazole as imidazole compounds, etc. Two or more of them can be appropriately mixed and used. In addition, paint baking temperature is set to 100 to 14
When the temperature is set to 0 ° C., it is preferable to use an active methylene compound and an oxime compound, particularly, ethyl acetoacetate and methyl ethyl ketoxime. The amount of the blocking agent added is 0.1 equivalent or more and less than 1.5 equivalents, preferably 0.3 to 0.5 equivalents, based on the isocyanate groups in the isocyanate compound.

Next, examples of the inorganic filler as the component (C) include calcium carbonate, talc, diatomaceous earth, kaolin clay, calcium silicate and precipitated barium sulfate. In the present invention, these are used alone. Or arbitrarily mixed. The amount of the inorganic filler is 10 parts by weight based on 100 parts by weight of the acrylic polyol.
0 to 700 parts by weight, preferably 300 to 600 parts by weight. If the amount is less than 100 parts by weight, the tensile strength of the obtained coating film is reduced, and the corrosion resistance and the chipping noise resistance are reduced. If it exceeds 700 parts by weight, the coating film becomes brittle, and peeling due to chipping increases. In addition, the paintability is deteriorated, resulting in poor appearance after painting.

Further, the additive as the component (D) is used as a reaction catalyst between an acrylic polyol and a curing agent, that is, an isocyanate compound. Specifically, dibutyltin dilaurate or dioctyltin dilaurate and a mixture of both are used. A mixture is used. The amount of the additive is 3.0 to 50 parts by weight, preferably 10 to 30 parts by weight, based on 100 parts by weight of the acrylic polyol. 3.
If the amount is less than 0 parts by weight, the effect as a reaction catalyst cannot be exerted, resulting in poor coating film curing and no chipping noise reduction effect. On the other hand, if it exceeds 50 parts by weight, the curing of the coating film is accelerated too much, and the toughness of the coating film deteriorates. In addition, dripping occurs at the time of application, and fire that generates bubbles and the like at the time of baking is caused.

As described above, the coating composition of the present invention comprises the above four components as essential components, but includes a coloring pigment for coloring, an antioxidant for improving weather resistance, a surfactant for defoaming, Further, other additives such as a dispersant for adjusting the dispersibility and viscosity of the coating material can be appropriately blended. The four components are raw material components (initial components), and the coating composition of the present invention contains the four components at the time of production or immediately thereafter, but these components are consumed and disappear over time. And so on. In particular, when the component (D) is allowed to coexist, the urethane reaction between the component (A) and the component (B) may proceed, and in this case, other components such as a urethane-based material may be mixed.

Next, the soundproof coating structure for a vehicle according to the present invention will be described in detail. As mentioned above, this soundproof paint structure
The film thickness of the above-described vehicle soundproof coating composition is 0.1 to 1.
A coating film having a thickness of 0 mm is laminated on a portion to be coated of a vehicle.
In other words, the soundproof coating structure of the present invention is formed by coating the above-mentioned coating composition on a portion to be coated of a vehicle in a range of a coating film thickness of 0.1 to 1.0 mm and heat-curing.

Here, the part to be coated on the vehicle is not particularly limited. However, considering the chipping resistance and chipping noise performance of the soundproofing coating composition of the present invention, the underside of the floor of an automobile body or the like can be used. It is preferable to be an electrodeposition coating portion on the outer surface of the side sill portion (see FIGS. 1 and 2). The coating thickness is in the range of 0.1 to 1.0 mm as described above, but is preferably in the range of 0.3 to 0.4 mm. If the coating film thickness is less than 0.1 mm, the soundproofing and chipping resistance will be insufficient, and if it exceeds 1.0 mm, sagging will occur and the weight will increase.

The method of coating the part to be coated is not particularly limited, and examples thereof include application using a brush or the like, immersion in a coating composition liquid, and spray coating using a spray or the like. In addition, heat curing can be appropriately changed depending on the type and the amount of various components used,
Typically, it is preferably performed at 100 to 140 ° C. 1
If the temperature is lower than 00 ° C., the reaction becomes insufficient and sufficient performance cannot be obtained. If the temperature exceeds 140 ° C., the coating becomes brittle and the peeling due to chipping increases.

In the coating structure of the present invention, a coating film of the present coating composition may be formed on the electrodeposition coating portion, and the intermediate coating or top coating may be further applied on the coating film. Examples of such an intermediate coating include coating by a commonly used automotive intermediate coating.

[0023]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

(Example 1) Dainippon Ink Co., Ltd. having 50 hydroxyl groups as the main component (A) acrylic polyol
100 parts by weight of BU-955 (trade name, manufactured by Dainippon Ink Co., Ltd., trade name: D)
B-980K) in an amount of 60 parts by weight. The mixed resin solution was heated to 35 ° C., and (C) 50 parts by weight of calcium carbonate, 25 parts by weight of talc, and 25 parts by weight of calcium silicate were blended as inorganic fillers in a total amount of 100 parts by weight. The mixture was stirred and mixed with a stirrer for 30 minutes. Next, two-pass dispersion was carried out by a roll disperser so that the particle diameter became 30 μm or less, to obtain a paste. This paste was mixed with 3 parts by weight of dibutyltin terephthalate as an additive (D), and further added with butyldiglycol acetate 7
60 parts by weight of a mixed organic solvent consisting of 0% and 30% petroleum naphtha was added. Further, the paste solution was stirred and mixed by a disper stirrer for 1 hour, and then subjected to a defoaming treatment in a vacuum state to obtain a soundproof coating composition for vehicles of this example.

The obtained soundproof coating composition for vehicles was prepared by adding 20 μm
m cold rolled steel plate (SPCC plate) (300 x 300 x 0.8 m) specified in JIS G3141
m and 150 × 70 × 0.8 mm), and applied with an airless pump so that the film thickness after firing becomes 0.1 mm, 0.35 mm and 1.0 mm.
After baking for 2 minutes, baking was performed at 140 ° C. for 20 minutes to obtain coated plates having three different film thicknesses for each of the two steel plates.

(Examples 2 to 6 and Comparative Examples 1 to 6) The same operation as in Example 1 was repeated using the formulations shown in Table 1, and the soundproof paints for vehicles of Examples 2 to 6 and Comparative Examples 1 to 6 were repeated. A composition was obtained. As the inorganic filler (C) blended in Examples 2 to 6 and Comparative Examples 1 to 6, calcium carbonate: talc: calcium silicate was used in a weight ratio of 50: 2 as in Example 1.
The mixed agents contained at a ratio of 5:25 were blended at the ratios shown in Table 1, respectively. Further, the additive (D) was also used in Example 1.
The same dibutyltin terephthalate was blended in the proportions shown in Table 1. Further, as for the organic solvent, the same mixed organic solvent comprising 70% of butyl diglycol acetate and 30% of petroleum naphtha as in Example 1 was used.
Was blended in the ratio described in the above section. Further, the same operation as in Example 1 was repeated to obtain coated plates of Examples 2 to 6 and Comparative Examples 1 to 6 having three different film thicknesses, respectively.

(Comparative Example 7) Tokalic # 8505 (trade name: polyester urethane) (trade name, manufactured by Tokyo Chemical Paint Co., Ltd.) conventionally used was electrodeposited at 20 μm in the same manner as that used in Examples. JIS G painted
Cold rolled steel plate (SPCC plate) (300
× 300 × 0.8mm and 150 × 70 × 0.8mm)
On top, the coating was performed by an airless pump so that the film thickness after firing would be 0.1 mm, 0.35 mm, and 1.0 mm, and calcined at 120 ° C. for 10 minutes.
For 20 minutes to obtain coated plates having three different film thicknesses.

[0028]

[Table 1]

[Evaluation of Performance] The following evaluation tests were performed on the coated plates obtained in the above examples. Table 2 shows the obtained results.

(1) Anti-chipping sound performance The coated plate of 300 × 300 × 0.8 mm obtained in each example was fixed to a jig at an angle of 30 ° with respect to the horizontal, and just above the center of the surface of the coated plate. A 2 g steel ball was allowed to fall freely from a height of 2 m, and a sound when the steel ball collides with the painted plate was sided at a position 150 mm from the center of the back surface of the painted plate. The sidetone level of the coated plate of each example was evaluated on the following three levels. ○: not disturbing as unpleasant sound △: slightly disturbing as unpleasant sound ×: disturbing as unpleasant sound

(2) Chipping scratch resistance The coated plate of 150 × 70 × 0.8 mm obtained in each example was
SAE J400 (Test of chip Res
instance of Surface Coatin
g) by the gravureometer specified in g).
At 49 MPa, 500 g of No. 6 quarry specified in JIS A5001 (quarry for roads) was injected. This operation 5
After repeating the number of times, the situation of damage due to stone jumping (chipping) was visually evaluated. ○: scratch is not noticeable △: scratch is slightly noticeable ×: scratch is noticeable

(3) Chipping corrosion resistance The coated plate of 150 × 70 × 0.8 mm obtained in each example was
SAE J400 (Test of chip Res
instance of Surface Coatin
g) by the gravureometer specified in g).
At 49 MPa, 500 g of No. 6 quarry specified in JIS A5001 (quarry for roads) was injected. This operation 5
After repeating the test twice, a salt spray test specified in JIS Z2371 was performed for 72 hours, and the rust generation on the surface of the coated plate was visually evaluated. ：: No rust is generated △: Rust is generated a little ×: Rust is generated a lot

(Appearance of Coating) With respect to the surface of the coated plate obtained in each example, the occurrence of sagging and armpits was visually evaluated. ：: No sagging, no armpits △: Slightly sagging, no armpits ×: Many sagging, armpits

[0034]

[Table 2]

From Table 2, it can be seen that the coated plates of the examples belonging to the scope of the present invention (corresponding to the coating structure of the present invention) were superior to the coated plates of the comparative examples outside the scope of the present invention. The results show the performance, confirming the effectiveness of the present invention. At the present time, Example 2 shows the best effect from the viewpoints of chipping noise, chipping damage, corrosion resistance and appearance.

[0036]

As described above, according to the present invention, a specific isocyanate compound, acrylic polyol, or the like is used at a predetermined compounding ratio. Provided is a soundproof paint composition for vehicles and a soundproof paint structure which reduce damage, have excellent finished appearance, generate less noise due to rock hit during running, and do not cause discomfort to occupants. That is, chipping noise due to rock jumps during running of the vehicle can be reduced, and a tough coating film with excellent scratch resistance can be obtained, so that rust generation from the scratched portion can also be reduced. Further, if the composition of the coating composition of the present invention is adopted,
The prevention of sagging and displacement during coating is improved, and a thick film coating, which could not be realized conventionally, becomes possible, and an excellent effect of improving the degree of freedom of coating can be obtained. Furthermore, since such a thick film coating is realized, it is not necessary to apply the coating twice, so that it is possible to obtain an excellent effect of reducing the productivity and improving the finished appearance of the coating.

[Brief description of the drawings]

FIG. 1 is a side view showing an example of a conventional vehicle, showing a side sill portion.

FIG. 2 is a view showing a coating configuration of a cross-section taken along arrow in FIG.

[Explanation of symbols] Side sill part Body panel Electrodeposition coating Undercoat Intermediate coating or top coating

Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) C09D 5/00 C09D 5/00 Z (72) Inventor Shin Mabuchi 1-21-23 Fuchinobe, Sagamihara-shi, Kanagawa Prefecture Tokyo Chemical Coating Co., Ltd. F term (reference) 3D023 BA02 BB29 BC01 BD04 BD09 BE04 BE31 3D114 AA17 BA01 CA10 4D075 AE03 DA06 DB02 DC12 EA05 EB22 EB38 EC13 4J038 DG191 DG261 DG271 DG281 DG301 GA03 HA286 HA376 HA08

Claims (10)

[Claims] (A) 100 parts by weight of an acrylic polyol, (B) 60 to 300 parts by weight of an isocyanate compound, (C) 100 to 700 parts by weight of an inorganic filler, and (D)
A soundproof paint composition for vehicles, comprising 3.0 to 50 parts by weight of an additive. 2. (A) 60 to 300 parts by weight of an isocyanate compound, (C) 100 to 700 parts by weight of an inorganic filler and (D) based on 100 parts by weight of an acrylic polyol.
A soundproof coating composition for vehicles, which is obtained by blending 3.0 to 50 parts by weight of an additive. 3. The method of claim 1, wherein (A) the acrylic polyol is contained in one molecule.
The soundproof coating composition for vehicles according to claim 1 or 2, wherein the composition has from 5 to 150 hydroxyl groups. 4. The isocyanate compound (B) is tolylene diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, liquid modified diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate, xylyl diisocyanate, cyclohexyl diisocyanate, cyclohexane phenylene diisocyanate, naphthalene-1,5. 4. At least one member selected from the group consisting of -diisocyanate, isopropylbenzene-2,4-diisocyanate, and polypropylene glycol and tolylene diisocyanate addition reaction product. 4. The soundproof paint composition for vehicles according to any one of the above items. 5. (C) The inorganic filler is calcium carbonate,
The vehicle sound-insulating coating composition according to any one of claims 1 to 4, wherein the composition is at least one selected from the group consisting of talc, kaolin clay, calcium silicate, and precipitated barium sulfate. object. 6. The vehicle soundproof coating composition according to claim 1, wherein (D) the additive is dibutyltin dilaurate and / or dioctyltin laurate. 7. A mixed agent of (B) hexamethylene diisocyanate as an isocyanate compound, (C) calcium carbonate, talc and calcium silicate as an inorganic filler,
(D) The soundproof coating composition for vehicles according to any one of claims 1 to 6, wherein dibutyltin dilaurate is selected as an additive. 8. A film thickness of 0.1 to 1.0 mm of the vehicle sound-insulating coating composition according to any one of claims 1 to 7.
A soundproof coating structure for a vehicle, characterized in that the coating film is laminated on a portion to be coated of the vehicle. 9. The soundproof coating structure for a vehicle according to claim 8, wherein the portion to be coated is an electrodeposition coating portion on a lower surface of a floor of a vehicle body or an outer surface of a side sill portion. 10. The vehicle soundproof coating structure according to claim 8, wherein a middle coat is applied on the coating film of the vehicle soundproof coating composition.