KR101596441B1 - Compositions for automobile undercoating - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for oil-based undercoating of automobiles which is applied to the lower part of a vehicle body by means of rust prevention of automobiles. The composition for automotive undercoating of the present invention is excellent in workability due to no occurrence of fogging phenomenon and spalling phenomenon, and is excellent in acid resistance, basic resistance, heat resistance, impact resistance and adhesion, Can be usefully used for improvement.

Description

Compositions for automobile undercoating < RTI ID = 0.0 >

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for oil-based undercoating of automobiles which is applied to the lower part of a vehicle body by means of rust prevention of automobiles.

The lower part of the vehicle is coated with calcium chloride on the road when snow comes in winter. It is exposed to summer rain, salt water in the beach, and is exposed to shocks caused by stones scattered by the tires when they hit the bottom of the car.

In order to prevent damage caused by such corrosion and impact to the under vehicle, the vehicle body is undercoated with a PVC type vibration damping material at the time of shipment. However, the range of application is very limited and PVC resin is used as the basic composition. Structure. Dehydrochlorination reaction takes place at a high temperature of usually 180 ° C or higher, and hydrogen and chlorine combine to cause pyrolysis which generates HCl. Therefore, there is a further need for an underbody coating other than the PVC type for preventing corrosion and impact at the lower portion of the vehicle.

These undercoating agents can be largely divided into oil-based and water-based coatings. Depending on the type and composition ratio of the raw materials used, inorganic fillers precipitate and are not properly sprayed. Over time, the coating may break or break. In addition, when the undercoating agent is applied, the solvent and a part of the raw material are scattered to the work site, and the performance and the workability are greatly different.

The undercoating agent using asphalt as a main ingredient has a strong smell due to the use of BTX solvent and has a problem of polluting the workplace due to the blowing in the air of the solvent or asphalt, and the workability is lowered due to the late drying speed of the asphalt. Also, there is a problem that the coating film is melted due to the asphalt component at a high temperature, so that the undercoating agent becomes sticky or partly broken during the summer. Among the undercoating materials using asphalt as the main material, the chemical resistance is weak and the coating film may be peeled off or cracked, and it is vulnerable to impact.

An undercoating agent using an acrylic emulsion resin as a binder has strong fragrance due to the use of BTX solvent and has a problem that adhesiveness is significantly lower than that of a solvent resin. When the undercoating agent becomes too hard after being completely dried, There is a problem that when the scattered stones hit the floor of the car, the coating breaks.

Numerous papers and patent documents are referenced and cited throughout this specification. The disclosures of the cited papers and patent documents are incorporated herein by reference in their entirety to better understand the state of the art to which the present invention pertains and the content of the present invention.

The present inventors have made efforts to solve the above problems. In particular, when the undercoating liquid containing an acrylic emulsion resin and an asphalt is sprayed, a mist, a blowing phenomenon, and a solvent odor are improved We have made efforts to develop an undercoating agent with excellent workability. As a result, an undercoating agent containing a diene rubber, a petroleum resin, an inorganic filler, a dispersant and a solvent has been developed, and it has been found that not only the occurrence of haze phenomenon and yarn breakage but also the odor is small and the drying time is fast, And exhibits excellent physical properties in terms of basicity, heat resistance, impact resistance and adhesiveness, thereby completing the present invention.

Accordingly, an object of the present invention is to provide a composition for automotive undercoating.

Other objects and advantages of the present invention will become more apparent from the following detailed description of the invention, claims and drawings.

According to one aspect of the present invention, there is provided a composition for automotive undercoat comprising:

Diene rubber and petroleum resin;

Inorganic filler;

Dispersing agent; And

solvent.

The present inventors have made efforts to solve the above problems. In particular, when the undercoating liquid containing an acrylic emulsion resin and an asphalt is sprayed, a mist, a blowing phenomenon, and a solvent odor are improved We have made efforts to develop an undercoating agent with excellent workability. As a result, an undercoating agent containing a diene rubber, a petroleum resin, an inorganic filler, a dispersant and a solvent has been developed, and it has been found that not only the occurrence of haze phenomenon and yarn breakage but also the odor is small and the drying time is fast, It is confirmed that the copolymer exhibits excellent physical properties in terms of basicity, heat resistance, impact resistance and adhesiveness.

The diene-based rubber means a synthetic rubber produced by using a diene-based compound such as butadiene, isoprene, chloroprene, etc. as a main unit. In some cases, such diene rubbers may contain natural rubbers, and these rubbers have a carbon-carbon double bond in the main chain and thus can be vulcanized.

According to the present invention, the diene-based rubber provides an elastic force and protects the lower portion of the vehicle from an impact generated when a small stone scattered by a tire during a vehicle running hits the bottom of the vehicle.

According to one embodiment of the present invention, the diene rubber is selected from the group consisting of SBR (styrene butadiene rubber), NBR (nitrile butadiene rubber), chloroprene rubber, isoprene rubber and butadiene rubber Is selected.

In one specific example, the diene rubber is SBR.

According to one embodiment of the present invention, the diene rubber is contained in an amount of 1-10% by weight based on the total weight of the composition. If the diene-based rubber is contained in an amount less than 1% by weight, it may be insufficient to impart an elastic force. If the diene rubber is contained in an amount exceeding 10% by weight, flowability of the undercoating damping agent may decrease, .

The petroleum resin refers to a plastic obtained by polymerizing various kinds of raw materials containing olefins or diolefins as an oil produced as a byproduct of petroleum refining process or petrochemical industry.

According to the present invention, the petroleum resin serves to enhance the adhesion of the composition for undercoating.

According to one embodiment of the present invention, the petroleum resin is selected from the group consisting of an aliphatic petroleum resin, an aromatic petroleum resin, a copolymerized petroleum resin, a coumarone indene resin and a hydrogenated dicyclopentadiene petroleum resin.

According to one embodiment of the present invention, the petroleum resin is included in an amount of 5-25% by weight based on the total weight of the composition. If the amount of the petroleum resin is less than 5% by weight, the adhesion force at the bottom of the vehicle may be reduced. If the amount of the petroleum resin is more than 25% by weight, the adherence enhancement effect may be insufficient.

According to one embodiment of the present invention, the inorganic filler is selected from the group consisting of talc, mica, calcium carbonate (CaCO ₃ ), silica, wollastonite (CaSiO ₃ ), clay, diatomaceous earth, titanium oxide and zeolite.

In one particular example, the inorganic filler is talc.

According to one embodiment of the present invention, the inorganic filler is contained in an amount of 20 to 40% by weight based on the total weight of the composition.

According to the present invention, the dispersing agent reduces the surface tension in the dispersing step to facilitate production of the product, adsorbs on the surface of most inorganic pigments and extender pigments, and is connected to each other by hydrogen bonding or the like, Can have some influence. In addition, the dispersant enables the introduction of an amine into a low molecular dispersant or the introduction of ions to one end or both ends of the pigment, thereby effectively imparting physical properties to a pigment having a charge on the surface, and a molecular weight of 500-2,000 g / mol is suitable. In the present invention, various known organic and inorganic dispersants can be used. For example, a fatty acid modified polyamide type dispersant (for example, afcona 5009) may be used.

According to one embodiment of the present invention, the dispersing agent is contained in an amount of 1-5% by weight based on the total weight of the composition.

The components described above are mixed with a solvent to prepare a composition for undercoating.

According to one embodiment of the present invention, the solvent is not a BTX solvent.

According to one embodiment of the present invention, the solvent is a naphtha solvent (solvent naphtha).

According to one embodiment of the present invention, the solvent is included in an amount of 25-50 wt% based on the total weight of the composition.

According to one embodiment of the present invention, the composition for undercoating of the present invention may further comprise a clay mineral. The clay mineral imparts an appropriate viscosity to the composition for undercoating and enables a constant thickness to be maintained upon application.

The clay minerals usable in the present invention include, for example, bentonite, zeolite, smectite, phyllosilicate, montmorillonite, saponite, bederite, nontronite, vermiculite, kaolinite and halosite.

According to one embodiment of the present invention, the clay mineral is bentonite.

According to one embodiment of the present invention, the clay mineral is included in an amount of 3-15% by weight based on the total weight of the composition. If the clay mineral is contained in an amount of less than 3% by weight, a problem may arise in the uniform thickness and storage stability of the coating film. If the clay mineral is contained in an amount exceeding 15% by weight, workability may be deteriorated.

According to one embodiment of the present invention, the composition for undercoating of the present invention may further comprise carbon black. Specifically, in the present invention, carbon black may be used to maintain the hue from moisture or dust after application.

According to one embodiment of the present invention, the carbon black is contained in an amount of 0.5-5% by weight based on the total weight of the composition. If the content of the carbon black is less than 0.5% by weight, the color may not be clear, and if it exceeds 5% by weight, the adhesion may be deteriorated.

The composition for undercoating of the present invention may further include a component for improving rust resistance in addition to the above components. Examples of the components for this purpose include borosilicates, petroleum oxide barium salts and the like. The rust-preventive-improving component may be contained in an amount of 3-10 wt% based on the total weight of the composition.

The features and advantages of the present invention are summarized as follows:

(i) The present invention relates to a vehicle undercoat which is improved in workability by using a combination of a diene rubber, a petroleum resin, an inorganic filler, a dispersant and a solvent in place of the BTX solvent, asphalt and acrylic emulsion resin used in conventional undercoating agents ≪ / RTI >

(ii) The automotive undercoating composition of the present invention has excellent workability due to no occurrence of haze phenomenon and spalling phenomenon, and is excellent in acid resistance, resistance to alkali, heat resistance, impact resistance and adhesion, It can be usefully used for improving the dustproof property and the rust prevention property.

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood by those skilled in the art that these embodiments are only for describing the present invention in more detail and that the scope of the present invention is not limited by these embodiments in accordance with the gist of the present invention .

Example

Example 1: Preparation of composition for automobile undercoating

The components and contents shown in the following Table 1 were prepared in accordance with a general undercoating agent for automobile manufacturing method. The resin (SBR and petroleum resin) was added to a certain amount of solvent, and then a dispersant (Afcona, afcona 5009) was added. Thereafter, a powder (talc) was added, the solvent was further added according to the viscosity, and the mixture was stirred at a high speed to prepare an undercoating composition.

Comparative Examples 2 and 3 correspond to undercoating agents prepared by conventional techniques, and Comparative Examples 4 to 6 correspond to commercially available products. Table 2 shows the performance evaluation test results, and Table 3 shows the workability evaluation test results.

Undercoat composition Example Comparative Example One 2 3 4 5 6 Company A (Wurst) Company B (3M) Company C (Renewal) Composition Component (% by weight) SBR 5 - - - - - Petroleum resin
(Regalite
C6100,
EASTMAN) 20 - 25 Acrylic resin - 25 - Dispersant
(Afcona 5009,
Afcona) 3 3 3 Inorganic filler 30 30 15 asphalt - - 15 Bentonite 10 10 10 Carbon black One One - Naphtha Solvent 31 - - Aromatic hydrocarbon solvent - 31 32 Sum 100 100 100

exam
Item Workability evaluation result standard Test Methods Example Comparative Example One 2 3 4 5 6 Texture Rubber
Texture Fla
stick
Texture Payne
The
Texture Payne
The
Texture Payne
The
Texture Payne
The
Texture - Sensibility evaluation using hands Exterior Good Good Good Good Good Good There should be no abnormality in the coating Visual evaluation smell weakness Strong Strong weakness Strong Strong Not to be disorganized Samples were taken in glass bottles and more than five panels were scented to evaluate smog
phenomenon Not occurring Occur Occur Occur Occur Occur Solvent spill should not occur The sample was injected into a 1-liter container and sprayed with a spray gun, and the degree of solvent blowing was visually evaluated by a panel of three or more persons room
Blur Not occurring Occur Occur Not occurring Occur Not occurring There should be no yarn breakage. The sample was injected into a 1-L container and sprayed with a spray gun. dry
time speed usually usually speed usually usually Drying time measurement An undercoating agent was applied to a steel sheet having a thickness of 76 mm x 157 mm in an electrodeposition coating process to a thickness of 0.5 mm and allowed to stand for 100 seconds on a sample for 5 seconds on a sample applied every 1 minute until the undercoating agent did not appear on the weight Measure the time of

- Performance evaluation result standard Test Methods Example Comparative Example One 2 3 4 5 6 Acid resistance More than
none More than
none Coat
exfoliation More than
none Coat
exfoliation More than
none Abnormally
Not to be KS M ISO
2812-1 Basicity More than
none More than
none Coat
exfoliation More than
none Coat
offshoot More than
none Abnormally
Not to be KS M ISO
2812-1 Heat resistance More than
none More than
none Coat
record,
weakening More than
none Coat
record,
weakening Coat
record,
weakening Abnormally
Not to be Judging whether the coating film was deformed after being stored in an oven at 80 ° C for 360 hours Impact resistance More than
none More than
none Coat
Breakaway More than
none More than
none Coat
Breakaway Abnormally
Not to be KS D 6711 Adhesiveness More than
none Bad More than
none More than
none More than
none More than
none Disengaged from the film
Not to ASTM D
3359

The compositions for automotive undercoats prepared in the above Examples and Comparative Examples were tested for texture, appearance, odor, haze, yarn breakage and drying time. The results are shown in Table 2, Heat resistance, impact resistance and adhesiveness were tested, and the results are shown in Table 3. < tb > < TABLE >

As a result, as shown in Table 2, the undercoating composition of the present invention was able to protect the lower portion of the vehicle from impact with an elastic rubber texture and did not give off a bad smell in the aromatic hydrocarbon solvent. Further, in the workability evaluation, there was no fogging phenomenon caused by the spraying of the solvent by spraying, and a part of the resin was not stretched like a thread (Table 2).

Further, as shown in Table 3, the composition for undercoating of the present invention had no abnormality in acid resistance, alkali resistance, heat resistance, impact resistance and adhesiveness. In Comparative Examples 3 and 5 using asphalt as the main ingredient, peeling of the coating film was observed in the acid-resistant basic evaluation, and it was confirmed that the coating film melted or weakened at 80 ° C (Table 3).

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the present invention. Accordingly, the actual scope of the present invention will be defined by the appended claims and their equivalents.

Claims (9)

Composition for automotive undercoating comprising:
(a) 1-10% by weight of a diene rubber and 5-25% by weight of a petroleum resin;
(b) 20 to 40% by weight of an inorganic filler;
(c) 1-5% by weight of a fatty acid modified polyamide as a dispersant;
(d) 25-50 wt% naphtha solvent as solvent;
(e) 3-15% by weight of clay mineral; And
(f) 0.5-5% by weight of carbon black,
The diene rubber of (a) is selected from the group consisting of SBR (styrene butadiene rubber), NBR (nitrile butadiene rubber), isoprene rubber, and butadiene rubber, the inorganic filler is selected from talc, mica (mica), calcium carbonate (CaCO _3), silica, wollastonite (CaSiO _3), clays, diatomaceous earth, the group consisting of titanium oxide and zeolites.
delete delete delete delete The method of claim 1 wherein the clay mineral is selected from the group consisting of bentonite, zeolite, smectite, phyllosilicate, montmorillonite, saponite, beellite, nontronite, vermiculite, kaolinite and halosite . delete delete delete