JP2014210900A - Plastisol composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plastisol composition which forms a coating film having high chipping resistance and a high vibration damping property.SOLUTION: In one embodiment, there is provided the plastisol composition which contains at least a thermoplastic resin, a plasticizer, filler, an adhesion imparting agent, and which uses, as a first component of the plasticizer, an aromatic ester having a phenyl group and/or a sulfone group including an alkyl benzyl phthalate and/or a phenyl alkylsulfonate and which uses, as a second component of the plasticizer, a dialkyl phthalate of an aromatic ester having no phenyl group nor sulfone group. In another embodiment, there is provided the plastisol composition in which the above first component is an alkyl benzyl phthalate and/or a phenyl alkylsulfonate and, the second component is a dialkyl phthalate and, as the above thermoplastic resin, an acrylic resin and/or a vinyl chloride-based resin are used.

Description

The present invention relates to a coating material applied to, for example, automobiles, and particularly to automobiles. In addition to chipping resistance, the present invention has effective vibration damping properties in the outside air temperature region where the automobiles travel. The present invention relates to a plastisol composition that can be used for an undercoat to be applied to a floor under such as a floor portion or a wheel house portion, and can also be used for a floor upper or side surface.

For example, a part of a tool structure or a housing thereof, a mechanical structure and the housing thereof, a structure (engine, electric motor, transformer, etc.) including parts that are technically movable and a housing thereof, a structure such as an automobile Elastic structures such as (vehicle body surfaces, sound absorbing walls, etc.) are usually exposed to vibrations, and those vibrations that are movable and structurally propagate through the skeleton and air. Therefore, in general, a material having damping properties is applied to the structure in which those vibrations are expressed in order to suppress the vibrations.

In automobiles, vibrations generated from the engine, vibrations received from the road surface during travel, etc. are propagated to the vehicle body via the structure and air, so vibration suppression paints and asphalt are used for the purpose of suppressing vibration and improving quietness. Generally, a material having vibration damping properties, such as a sheet-shaped vibration damping material (asphalt sheet) mainly composed of, is applied to the floor upper.

On the other hand, in floor unders of automobiles, wheel houses, etc., the chipping phenomenon that the coating film is peeled off due to the collision of pebbles and gravel that the tire jumps up when the car is running, In order to prevent the chipping phenomenon by protecting the vehicle body from rock jumping, sand jumping, etc., chipping-resistant paint is applied as an undercoat.

  As such a chipping-resistant paint for undercoat, for example, as shown in Patent Document 1, for undercoat containing acrylic polymer fine particles, plasticizer, filler, block type urethane resin, curing agent and foaming agent An acrylic sol is disclosed.

JP 2001-329208 A

By the way, in recent years, there has been a demand for weight reduction of automobiles mainly for the purpose of improving the fuel efficiency of automobiles with the ultimate goal of suppressing global warming and protecting the global environment.
Here, in conventional anti-chipping paints for undercoats such as Patent Document 1, the paint distribution is usually used to form a paint film with an emphasis on anti-chipping properties. The coating film formed after heating and drying has relatively strong coating film properties and is effective for chipping resistance, but is not very effective for suppressing vibrations and is effective in the outside air temperature range where the car runs. It did not have a good damping performance.
In other words, in the structure of conventional automobiles, the material applied to the floor upper is mainly responsible for effective vibration damping, and separately from this, chipping resistance is applied to the floor underside of automobiles such as the under floor and wheel house parts. As a result, the weight ratio of materials occupying secondary materials such as vibration damping materials and chipping-resistant materials in the entire automobile has increased. It was.
For this reason, it has not been possible to cope with the recent trend of lighter automobiles.

Then, this invention is made | formed in view of the said situation, and provides the plastisol composition which can form a coating film with high chipping resistance and vibration damping property.

The plastisol composition of the invention of claim 1 is a plastisol composition comprising at least a thermoplastic resin, a plasticizer, a filler, and an adhesion-imparting agent, wherein the plasticizer includes a phenyl group and / or a sulfone group. A first component of an aromatic ester having a phenotype and a second component of an aromatic ester not having a phenyl group and a sulfone group are used in combination.

Here, the “thermoplastic resin” is a resin that is polymerized by heating, such as acrylic resin (including methacrylic resin), vinyl chloride resin, polyethylene, polypropylene, vinylidene chloride resin, polystyrene resin, polyvinyl acetate. Polytetrafluoroethylene, ABS (acrylonitrile-butadiene-styrene) resin, AS (acrylonitrile-styrene) resin, etc. can be used, and these can be used alone or in combination of two or more. .

The “plasticizer” plasticizes the thermoplastic resin to improve workability and flexibility. In the present invention, the plasticizer is an aromatic ester having a phenyl group and / or a sulfone group. In combination with the second component of the aromatic ester having no phenyl group and sulfone group, the thermoplastic resin is plasticized to improve the workability and flexibility of the plastisol composition, and to suppress vibrations. It was possible to promote sex.
Here, as the aromatic ester having a phenyl group and / or a sulfone group as the first component, benzylbutyl phthalate (butylbenzyl phthalate: BBP), octylbenzyl phthalate (octylbenzyl phthalate: OBP), benzyl phthalate Examples include alkyl benzyl phthalates such as isononyl (isononyl benzyl phthalate), dimethyl cyclohexyl phthalate (dimethyl cyclohexyl phthalate: DMCHP), phthalic acid polyesters, non-phthalic acid ester alkyl sulfonic acid phenyl esters, benzoic acid esters, etc. These can be used singly or in combination of two or more. In particular, alkyl benzyl phthalate and / or alkyl sulfonic acid phenyl ester are considered in view of good uniform dispersibility, low cost due to easy availability, low environmental impact, easy handling, etc. Is preferred.
The aromatic ester having no phenyl group and sulfone group as the second component includes diisononyl phthalate (diisononyl phthalate: DINP), dioctyl phthalate (dioctyl phthalate: DOP), dimethyl phthalate (dimethyl phthalate: DMP), phthalate Diethyl phthalate (diethyl phthalate: DEP), dibutyl phthalate (dibutyl phthalate: DBP), diheptyl phthalate (diheptyl phthalate: DHP), dinonyl phthalate (dinonyl phthalate: DNP), didecyl phthalate (didecyl phthalate: DDP) ), Dinormal octyl phthalate (dinormal octyl phthalate: DnOP), diisodecyl phthalate (diisodecyl phthalate: DIDP), bis-2-ethylhexyl phthalate (bis-2-ethyl phthalate: D) HP) and other dialkyl phthalates and trimellitic acid esters such as trimellitic acid tris (trioctyl trimellitate: TOTM), trioctyl linoleate (TOTN), triisooctyl trimellitate, triisodecyl trimellitate, etc. These may be used alone or in combination of two or more. In particular, dialkyl phthalate is preferable in view of good uniform dispersibility, easy cost, low cost, no environmental burden, ease of handling, and the like.

The “filler” is usually added to increase the amount of the plastisol composition and to give an appropriate strength to the formed coating film. For example, calcium carbonate, magnesium carbonate, barium sulfate, etc. Alkaline earth metal carbonates and sulfates, mica, mica, graphite, talc, clay, glass flakes (glass beads), leechite, kaolinite, wollastonite (acicular calcium metasilicate), silica Diatomaceous earth, gypsum, cement, converter slag, shirasu, zeolite, cellulose powder, powdered rubber and the like can be used, and these can be used alone or in combination of two or more.
Among them, scaly fillers such as mica (mica), graphite, talc (talc), clay, glass flakes (glass beads), leechite, kaolinite, and acicular fillers such as wollastonite (acicular calcium metasilicate) Damping fillers such as porous fillers such as calcium carbonate and silica are preferred.

Furthermore, the “adhesion imparting agent” is for improving the adhesion (adhesion) of the coating film to be formed to the object to be coated. For example, blocked isocyanate, polyamide, epoxy resin, polyamine, polyol, etc. These can be used, and these can be used alone or in combination of two or more. In particular, blocked isocyanates and polyamides have excellent adhesion to cationic electrodeposition coating surfaces, and epoxy resins have excellent adhesion improvements to oil-surface steel plates to which rust preventive oil and the like have adhered. Since it has an effect, it is preferable.

In the plasticizer of the plastisol composition of the invention of claim 2, the aromatic ester of the first component is alkylbenzyl phthalate and / or phenylsulfonic acid phenyl ester, and the aromatic ester of the second component is dialkyl phthalate. There is something.

Here, examples of the alkyl benzyl phthalate include benzyl butyl phthalate (butyl benzyl phthalate: BBP), octyl benzyl phthalate (octyl benzyl phthalate: OBP), and benzyl isononyl phthalate (isononyl benzyl phthalate). Is mentioned.
Further, as the alkylsulfonic acid phenyl ester, for example, mezamol (LANXESS Co., Ltd .; Mesamoll is a trademark) can be used.
Furthermore, as the dialkyl phthalate, for example, diisononyl phthalate (diisononyl phthalate: DINP), dioctyl phthalate (dioctyl phthalate: DOP), dimethyl phthalate (dimethyl phthalate: DMP), diethyl phthalate (diethyl phthalate: DEP), Dibutyl phthalate (dibutyl phthalate: DBP), diheptyl phthalate (diheptyl phthalate: DHP), dinonyl phthalate (dinonyl phthalate: DNP), didecyl phthalate (didecyl phthalate: DDP), di-normal octyl phthalate (di-octyl) Normal octyl phthalate (DnOP), diisodecyl phthalate (diisodecyl phthalate: DIDP), bis-2-ethylhexyl phthalate (bis-2-ethyl phthalate: DEHP), and the like.

The thermoplastic resin of the plastisol composition of the invention of claim 3 uses an acrylic resin and / or a vinyl chloride resin.

As used herein, “acrylic resin” broadly includes acrylic resin and methacrylic resin, and means a single polymer or copolymer of a monomer selected from acrylic acid alkyl ester, methacrylic acid alkyl ester, and the like. Specific examples of these monomers include methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, and isobutyl methacrylate. As such, various monomers can be used.

“Vinyl chloride resin” refers to a homopolymer of vinyl chloride, a copolymer with vinyl acetate, etc., and a mixture thereof. As vinyl monomers, vinyl acetate, propionic acid are used. Vinyl esters such as vinyl and vinyl stearate, vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether, maleic esters such as diethyl maleate, fumaric esters such as dibutyl fumarate, methyl acrylate, ethyl acrylate, 2 -Hydroxy of acrylic acid or methacrylic acid such as acrylic acid or methacrylic acid alkyl esters such as ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, etc. Alkyl esters, N- methylolacrylamide, N- methylolmethacrylamide, N- hydroxyethyl acrylamide, hydroxyalkyl amides of acrylic acid or methacrylic acid such as N- dihydroxyethyl methacrylamide, acrylonitrile, vinylidene chloride and the like.

The adhesiveness imparting agent of the plastisol composition of the invention of claim 4 uses one or more of blocked isocyanate, polyamide and epoxy resin.

Here, “block isocyanate” is a compound in which an isocyanate group of an isocyanate compound, which is a compound having an isocyanate group (—N═C═O), is inactivated by blocking with a compound having active hydrogen. Under certain conditions, this block is removed and the isocyanate group reacts with a compound having a hydroxyl group. The isocyanate compounds include aliphatic diisocyanates such as hexamethylene diisocyanate (HDI), aromatic diisocyanates such as tolylene diisocyanate (TDI), alicyclic diisocyanates such as isophorone diisocyanate and hydrogenated MDI, or these diisocyanates. Adducts, burettes, isocyanurates, adducts with polyhydric alcohols such as ethylene glycol and trimethylolpropane, and urethane prepolymers. However, among these, a block urethane prepolymer obtained by blocking a urethane prepolymer is generally most suitably used as an adhesiveness imparting agent.

“Polyamide” is a polyamide compound containing an active amino group and is generally obtained by reacting an aliphatic diamine such as hexamethylene diamine or a polyamine such as aromatic diamine with a polybasic acid. A typical example of such a polyamide is a reaction product of a polymerized fatty acid such as dimer acid or trimer acid obtained by thermal polymerization of an unsaturated fatty acid such as linoleic acid and a polyamine.

Further, the “epoxy resin” may be any one containing two or more epoxy groups in the molecule, for example, bisphenol A diglycidyl ether type epoxy resin, novolak type epoxy resin, alicyclic epoxy resin, glycidyl. An ester type epoxy resin, a linear aliphatic epoxy resin, etc. are mentioned. Moreover, this epoxy resin can also be of various modified types modified with rubber such as NBR in order to impart flexibility.

  The plastisol composition according to the invention of claim 1 is a plastisol composition comprising at least a thermoplastic resin, a plasticizer, a filler, and an adhesion imparting agent, wherein the plasticizer is a phenyl group and / or a sulfone group. A first component of an aromatic ester having a phenotype and a second component of an aromatic ester not having a phenyl group and a sulfone group are used in combination.

In order to obtain a coating film having both chipping resistance and vibration damping properties, the present inventors have paid attention to a plasticizer and, as a result of intensive experimental research, have found that the plasticizer of the plastisol composition has a phenyl group and / or Alternatively, by using together the first component of the aromatic ester having a sulfone group and the second component of the aromatic ester having no phenyl group and sulfone group, the thermoplastic resin is plasticized to improve the workability and flexibility of the plastisol composition. The present invention has been completed based on this finding, and it has been found that the vibration damping performance can be promoted while improving the performance.
That is, as a plasticizer, by using together the first component of an aromatic ester having a phenyl group and / or a sulfone group and the second component of an aromatic ester having no phenyl group and a sulfone group, Vibration suppression is promoted by the first component of the aromatic ester having a group and / or a sulfone group, and the plastic component of the thermoplastic resin is efficiently promoted by the second component of the aromatic ester having no phenyl group and sulfone group. When formed and coated, it is possible to form a coating film in which both chipping resistance and vibration damping properties are effectively ensured.

According to the plastisol composition of the second aspect of the invention, the aromatic ester of the first component of the plasticizer is an alkylbenzyl phthalate and / or phenylsulfonic acid phenyl ester, and the aromatic ester of the second component is an alkyl ester. Since the phthalate is used, vibration suppression is stably promoted mainly by the first component, and plasticization of the thermoplastic resin is more efficiently promoted by the second component. Therefore, in addition to the effect of the first aspect, a coating film exhibiting stable chipping resistance and vibration damping properties can be formed.

According to the plastisol composition of the invention of claim 3, the thermoplastic resin is an acrylic resin and / or a vinyl chloride resin, and the acrylic resin and the vinyl chloride resin are versatile among thermoplastic resins. It is easily available and has excellent properties in terms of adhesion, softening point, viscosity, surface hardness during drying, strength and the like, and is suitable for use as an undercoat material. Therefore, in addition to the effect of the first or second aspect, the cost can be reduced, and excellent performance such as strength can be secured in the coating film to be formed.

According to the plastisol composition of the invention of claim 4, the adhesiveness imparting agent is one using one or more of blocked isocyanate, polyamide, and epoxy resin. In addition to the effect described in any one of Items 3, the adhesion (adhesion) of the coating film to the article can be improved.
In particular, in block isocyanate and polyamide, the adhesiveness to the cationic electrodeposition coating surface can be improved, and in the epoxy resin, the adhesiveness to the oil surface steel plate to which oil or the like is adhered can be improved.

FIG. 1 is a graph showing measurement results of loss factors of plastisol compositions according to Examples 1 to 4 of the present invention in comparison with plastisol compositions of Comparative Examples 1 to 3.

Embodiments of the present invention will be described below.
A plastisol composition according to an embodiment of the present invention is a plastisol composition containing at least a thermoplastic resin, a plasticizer, a filler, and an adhesion-imparting agent, and includes a phenyl group and / or a sulfone as a plasticizer. A first component of an aromatic ester having a group and a second component of an aromatic ester not having a phenyl group and a sulfone group are used in combination.

In conventional anti-chipping coatings, diisononyl phthalate (diisononyl phthalate: DINP) or dioctyl phthalate (dioctyl phthalate) is readily available as a plasticizer and exhibits average performance such as paintability and storage stability. Dialkyl phthalates such as DOP) were most commonly used. However, when only a dialkyl phthalate, which is an aromatic ester having no phenyl group or sulfone group, is used as a plasticizer, chipping resistance is easily secured in the formed coating film, but vibration damping is expressed. It was difficult to ensure a desired vibration damping property even if a vibration damping filler was contained.
Therefore, in the present invention, the first component of the aromatic ester having a phenyl group and / or sulfone group is used in combination with the second component of the aromatic ester having no phenyl group and sulfone group, such as the above-mentioned dialkyl phthalate. The desired vibration damping can be ensured by promoting the vibration damping of the object.

Here, the inventors consider the reason why the aromatic ester having a phenyl group and the aromatic ester having a sulfone group promote vibration damping as follows.
Since aromatic electrons are delocalized by π electrons, aromatic esters having a phenyl group containing a large amount of aromatics tend to interact with the thermoplastic resin. Further, it is considered that hydrogen having high acidity contained in the aromatic ester having a phenyl group and the aromatic ester having a sulfone group is stabilized by an inducing effect. For this reason, the energy generated when an external force is applied can be stably converted into friction energy, and this effect improves vibration damping.

In addition, the present inventors have a low surface tension of dialkyl phthalate which is an aromatic ester having no phenyl group and sulfone group, which has been used as a conventional plasticizer, and has an aromatic ester having a phenyl group and a sulfone group. Since the surface tension of the aromatic ester is high, it is considered that the aromatic ester is caused by the compatibility and solubility in the thermoplastic resin due to the surface tension.
That is, the first component of an aromatic ester having a phenyl group and / or a sulfone group and the second component of an aromatic ester having no phenyl group and a sulfone group are used in combination, that is, plasticizers having different surface tensions are used in combination. Therefore, the properties of the thermoplastic resin plasticized by the plasticizer are appropriately controlled, and the chipping resistance that suppresses the properties of the thermoplastic resin well, such as pebbles etc. breaking through the coating film and damaging the coated surface. I think that it was possible to control the characteristics that balance the vibration control performance and the vibration suppression performance in the outside air temperature region where the car travels.

  Therefore, as a plasticizer, the first component of an aromatic ester having a phenyl group and / or a sulfone group and the second component of an aromatic ester having no phenyl group and a sulfone group are mainly used as a first component. The second component promotes the plasticity of the thermoplastic resin efficiently, and the plasticizing properties of the thermoplastic resin are appropriately controlled, so that the chipping resistance and the damping are improved when applied. It is possible to form and maintain a coating film in which both vibration properties are effectively secured.

  Here, as the aromatic ester having a phenyl group and / or a sulfone group as the first component, benzylbutyl phthalate (butylbenzyl phthalate: BBP), octylbenzyl phthalate (octylbenzyl phthalate: OBP), benzyl phthalate Examples include alkyl benzyl phthalates such as isononyl (isononyl benzyl phthalate), dimethyl cyclohexyl phthalate (dimethyl cyclohexyl phthalate: DMCHP), phthalic acid polyesters, non-phthalic acid ester alkyl sulfonic acid phenyl esters, benzoic acid esters, and the like. . In particular, alkyl benzyl phthalate and / or alkyl sulfonic acid phenyl ester are considered in view of good uniform dispersibility, low cost due to easy availability, low environmental impact, easy handling, etc. Is preferred.

  The aromatic ester having no phenyl group or sulfone group as the second component includes diisononyl phthalate (diisononyl phthalate: DINP), dioctyl phthalate (dioctyl phthalate: DOP), dimethyl phthalate (dimethyl phthalate: DMP). , Diethyl phthalate (diethyl phthalate: DEP), dibutyl phthalate (dibutyl phthalate: DBP), diheptyl phthalate (diheptyl phthalate: DHP), dinonyl phthalate (dinonyl phthalate: DNP), didecyl phthalate (didecyl phthalate) : DDP), dinormal octyl phthalate (dinormal octyl phthalate: DnOP), diisodecyl phthalate (diisodecyl phthalate: DIDP), bis-2-ethylhexyl phthalate (bis-2-ethylphthalate) : DiHP phthalate such as DEHP) and trimellitic acid such as trimellitic acid tris (trioctyl trimellitate: TOTM), trioctyl linoleate (TOTN), triisooctyl trimellitate, triisodecyl trimellitate Examples include esters. In particular, dialkyl phthalates are preferable in view of good uniform dispersibility, ease of acquisition, cost reduction, environmental impact, ease of handling, and the like. Among dialkyl phthalates, phthalates are preferable. Diisononyl acid (DINP) and dioctyl phthalate (DOP) are preferred.

  Next, the blending amount of the plasticizer in the embodiment of the present invention is the total amount of the second component of the aromatic ester having no phenyl group and sulfone group and the aromatic ester having a phenyl group and / or sulfone group in the entire plasticizer. The weight ratio of the first component is in the range of 30/70 to 70/30, preferably in the range of 40/60 to 60/40. This is because if the blending amount of the first component of the aromatic ester having a phenyl group and a sulfone group is too large, the storage stability of the plastisol composition is difficult to obtain, and if it is too small, the desired vibration damping property is difficult to obtain.

  Further, examples of the thermoplastic resin blended in the plastisol composition according to the present embodiment include acrylic resins (including methacrylic resins), vinyl chloride resins, polyethylene, polypropylene, vinylidene chloride resins, polystyrene resins, poly Vinyl acetate, polytetrafluoroethylene, ABS (acrylonitrile-butadiene-styrene) resin, AS (acrylonitrile-styrene) resin and the like are used. Above all, acrylic resin and vinyl chloride resin are versatile and easy to obtain, so it is possible to reduce costs, and various properties such as adhesion, softening point, viscosity, dry surface hardness, and strength. It is suitable for use as an undercoat material or the like.

In particular, when an acrylic resin is used as the thermoplastic resin, a plastisol composition (acrylic sol) that does not generate hydrogen chloride gas or dioxin during incineration can be obtained.
As the “acrylic resin”, for example, a single polymer or copolymer of a monomer selected from acrylic acid alkyl ester, methacrylic acid alkyl ester, and the like can be used. As these monomers, specifically, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, and the like are used.

  The acrylic resin is preferably core-shell type acrylic polymer fine particles composed of a core portion and a shell portion. When the acrylic polymer fine particle is a core-shell type, the storage stability of the prepared plastisol composition (acrylic sol) is improved, the viscosity increases during coating, and after polymerization by heating after coating (after heat curing) ) Bleeding can be suppressed. Further, when the acrylic polymer fine particles are of a core-shell type, it is preferable that the core portion is composed of a plasticizer affinity polymer and the shell portion is composed of a plasticizer non-affinity polymer. The polymer in the shell part, which is poorly compatible with the plasticizer, covers the core part that is compatible, thereby suppressing the increase in viscosity of the plastisol composition (acrylic sol) during storage and further improving the storage stability. Can do.

In addition, since the polymer of the shell portion exhibits compatibility with the plasticizer by heating to an appropriate temperature, there is no possibility of generating bleed after heat curing after coating. Incidentally, the core component is preferably composed of at least one methacrylate selected from, for example, n-butyl methacrylate, isobutyl methacrylate, ethyl methacrylate, or the like, or a copolymer thereof, and in particular, imparts flexibility to the coating film. In view of the above, it is more preferable to mainly use a copolymer of butyl methacrylate and isobutyl methacrylate. Thus, by making a core component highly compatible with a plasticizer, generation | occurrence | production of the bleeding after heat-hardening can be suppressed. The component of the shell part is preferably composed of at least one methacrylate selected from methyl methacrylate, benzyl methacrylate, styrene and the like, or a copolymer thereof. Thus, by making a shell component low compatibility with a plasticizer, the viscosity rise of the plastisol composition (acrylic sol) in storage can be suppressed and storage stability can be improved. In particular, from the viewpoint of further improving the storage stability, it is preferable that the component of the shell portion is mainly composed of methyl methacrylate.
Furthermore, the molecular weight of the acrylic resin is preferably 100,000 to several million in terms of weight average molecular weight from the viewpoints of chipping resistance, storage stability, etc., and the particle diameter is diffusion to the plasticizer. From the viewpoint of stability and storage stability, it is preferable to use one having a median diameter in the range of 0.1 μm to 10 μm.

By the way, according to definitions of terms in the text and explanation of JIS Z 8901 “Test Powder and Test Particles”, the median diameter is the number (or mass) larger than a certain particle diameter in the particle size distribution of the powder. ) is the particle diameter when occupying 50% of its Zenkonatai (diameter), i.e., a particle size of oversized 50%, usually expressed as the median diameter or 50% particle size and good D _50. By definition, the size of the particle group is expressed by the average particle diameter and the median diameter, but here, it is a value measured by the display of the product description and the laser diffraction / scattering method.
The “median diameter measured by the laser diffraction / scattering method” is a particle whose cumulative weight part is 50% in the particle size distribution obtained by the laser diffraction / scattering method using a laser diffraction particle size distribution measuring apparatus. This refers to the diameter (D ₅₀ ).
The above numerical values are not strict, but are approximate, and are naturally approximate values including errors due to measurement and the like, and do not deny errors of several percent. From the viewpoint of this error, further, from the viewpoint of diffusibility into the plasticizer and storage stability, the difference from the average particle diameter is very small, and it can be considered that the average particle diameter is equal to the median diameter.

Further, when a vinyl chloride resin is used as the thermoplastic resin, a plastisol composition having a flexible coating film and excellent durability can be obtained. Furthermore, the vinyl chloride resin has an advantage that it has good long-term storage stability at room temperature and is easy to use.
As the “vinyl chloride resin”, a vinyl chloride homopolymer (polyvinyl chloride) or a copolymer, that is, a copolymer of vinyl chloride and another vinyl monomer can be used. Examples of the vinyl monomers include vinyl esters such as vinyl acetate, vinyl propionate and vinyl stearate, vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether, maleates such as diethyl maleate, and dibutyl fumarate. Such as fumaric acid esters, acrylic acid such as methyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate or alkyl methacrylates, acrylic such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, etc. Hydroxyalkyl esters of acid or methacrylic acid, N-methylol acrylamide, N-methylol methacrylamide, N-hydroxyethyl acrylate De, hydroxyalkylamides of acrylic acid or methacrylic acid such as N- dihydroxyethyl methacrylamide, acrylonitrile, vinylidene chloride and the like. Among these, as the monomer copolymerized with vinyl chloride, vinyl acetate is the most common, and the adhesiveness of the coating film and the swelling gelation property with respect to the plasticizer are good.
The average polymerization degree of the vinyl chloride resin is preferably in the range of 500 to 2500 from the viewpoint of physical properties such as chipping resistance, and the median diameter thereof is 5 μm or less, preferably 3 μm or less. More preferably, it is 1.5 μm or less. When a large particle having a median diameter exceeding 5 μm is used, chipping resistance may be lowered.

Furthermore, as a filler to be blended in the plastisol composition according to the present embodiment, for example, carbonates and sulfates of alkaline earth metals such as calcium carbonate, magnesium carbonate, barium sulfate, mica (mica), graphite, Talc (talc), clay, glass flakes (glass beads), leechite, kaolinite, wollastonite (acicular calcium metasilicate), silica, diatomaceous earth, gypsum, cement, converter slag, shirasu, zeolite, cellulose powder, Powder rubber, zonolite, potassium titanate, bentonite, aluminum nitride, silicon nitride, zinc white, titanium oxide, calcium oxide, alumina, zinc oxide, iron oxide, magnesium oxide, titanium oxide, magnesium hydroxide, aluminum hydroxide, calcium silicate In addition, calcium carbonate whisker (acicular carbonate Lucicium), ceramic short fiber or its whisker, rock wool short fiber, glass fiber short fiber, potassium titanate short fiber, calcium silicate short fiber, aluminum silicate, carbon fiber short fiber, aramid fiber short fiber, sepiolite and other mineral fibers Organic hollows such as plastic fillers made of fibrous fillers such as various whiskers, hollow fillers such as glass balloons, silica balloons, resin balloons, carbon inorganic hollow spheres, and organic synthetic resins such as vinylidene chloride and acrylonitrile. A metallic filler such as an aluminum filler or an aluminum filler is used, and these can be used alone or in combination of two or more.
Among these, scaly fillers such as mica (mica), graphite, talc (talc), clay, glass flakes (glass beads), leechite, and kaolinite, which effectively attenuate vibration energy, It is preferable to use a damping filler such as acicular filler such as lastite (acicular calcium metasilicate) and porous filler such as calcium carbonate and silica. All of these vibration damping fillers are easily available, inexpensive, and have good compatibility with thermoplastic resins, so that the production cost of the plastisol composition can be reduced by blending it with the plastisol composition, and good damping can be achieved. Vibration characteristics can be obtained.

That is, when scaly fillers such as mica (mica), graphite, talc (talc), clay, glass flakes (glass beads), leechite, and kaolinite are used as fillers, mechanical energy is externally applied. In addition to being able to efficiently convert to shear stress in a thin elastomer phase sandwiched between fillers, frictional motion at the interface between the elastomer and filler, shearing between layers inside the filler, friction between fillers High vibration control can be achieved by exercise or the like. This vibration damping property changes depending on the properties (shape, elastic modulus, etc.) of the flaky filler. Specifically, the higher the aspect ratio (filler average diameter / filler thickness) of the filler is, the higher the elastic modulus is. High vibration damping can be demonstrated. Among the scale-like fillers, mica (mica) has a large aspect ratio and a high elastic modulus, and can greatly improve vibration damping particularly in a high temperature region, and has excellent strength and high rigidity. Since a vibration film can be obtained, it is preferable as a filler.
“Mica” is a generic name for natural minerals that are easy to peel off in a thin layer, and has elasticity, electrical insulation, and heat resistance. There are muscovite, phlogopite and biotite due to differences in ingredients. Any of these can be used, and it is also possible to use artificial mica synthesized by melting each component with heat. Incidentally, the major producers of natural mica are India, Sri Lanka, Canada, the United States, Russia, Brazil, China, South Africa, Madagascar, etc., and they can be obtained at a very low cost.

In addition, when a needle filler such as wollastonite (acicular calcium metasilicate) is used as a filler, the vibration damping property is improved by forming a network structure by entanglement with a thermoplastic resin during baking. Furthermore, the shear strength can be improved.
Incidentally, “wollastonite” is a mineral name mainly composed of calcium silicate (CaO.SiO ₂ ). Usually, SiO ₂ is about 50% by weight or more, CaO is about 47% by weight, and other Fe ₂ O _3. , Al ₂ O _3, etc., also known as wollastonite.
Furthermore, when a porous filler such as calcium carbonate or silica is used as the filler, the vibration energy can be effectively attenuated due to the porousness. In addition, the specific gravity of the coating film can be lowered to reduce the weight of the entire coating film.
In addition, this filler is blended in the range of 50 parts by weight to 800 parts by weight with respect to 100 parts by weight of the thermoplastic resin from the viewpoints of chipping resistance, vibration damping, and coating workability. It is preferable. If the amount of the filler is too large, the flexibility, elasticity and adhesion of the coating film will be reduced, and the chipping resistance and vibration damping will be reduced. On the other hand, if the amount of the filler is too small, the cohesive force will be insufficient. Workability is reduced.

  Furthermore, as an adhesiveness imparting agent blended in the plastisol composition according to the present embodiment, block isocyanate, polyamide, epoxy resin, polyamine, polyol and the like are used. In particular, when the plastisol composition is applied after undercoating by electrodeposition coating, it is preferable to use a block isocyanate or polyamide that exhibits excellent adhesion to the cationic electrodeposition coating surface, and the combination of these is most preferable. Moreover, it is also preferable to use an epoxy resin having an excellent effect of improving the adhesion to the oil surface steel plate to which rust preventive oil or the like is adhered during processing.

  Here, the “block isocyanate” as the adhesion-imparting agent is a relatively low molecular weight polyisocyanate component such as phenol, acid amide, lactam, lower monohydric alcohol, cellosolve, caprolactam, oximes such as methyl ethyl ketone oxime (MEKO), etc. The NCO group at the end is blocked with a blocking agent, and the polyisocyanate component includes aliphatic isocyanates such as hexamethylene diisocyanate (HDI), diphenylmethane diisocyanate (MDI), tolylene diisocyanate (TDI), metaphenylene diisocyanate. , Aromatic isocyanates such as naphthylene diisocyanate and triphenylmethane triisocyanate, alicyclic diisocyanates such as isophorone diisocyanate and hydrogenated MDI, or the like Isocyanate biuret of, isocyanurate, ethylene glycol, adduct of a polyhydric alcohol such as trimethylol propane, or the like urethane prepolymer and the like.

Among these, a block urethane prepolymer obtained by blocking a urethane prepolymer, a so-called block type urethane resin is most preferably used. Block type urethane resin uses a block type urethane resin because when the blocking agent is dissociated by heating after coating, a crosslinking reaction occurs due to intermolecular crosslinking of the urethane resin, and the urethane resin takes a network structure by the crosslinking reaction. The coating film formed in this way has good adhesion to the object to be coated and cold resistance and excellent chipping resistance.
The “block type urethane resin” includes α polyols such as polyether polyol and polyester polyol, diphenylmethane diisocyanate (MDI), tolylene diisocyanate (TDI), hexamethylene diisocyanate (HDI), and the like. A urethane resin obtained by reacting with isocyanate can be blocked using a blocking agent such as oxime or amine. As the urethane resin, it is desirable to use a urethane resin synthesized from polypropylene glycol (PPG) and tolylene diisocyanate (TDI) from the viewpoint of versatility. The blocking agent is an active hydrogen compound that binds to the isocyanate group of the urethane resin and dissociates when heated to a temperature that is stable at room temperature, such as phenols, lactams, oximes, amines, etc. However, since the dissociation temperatures of these blocking agents are different, the blocking agent is selected in consideration of the temperature at which the prepared plastisol composition is applied and heat-cured, that is, the processing temperature. It is desirable to do. In particular, when the processing temperature cannot be increased, or when it is applied to a part that is difficult to be heated to a higher temperature depending on the position relative to the heating device, such as the inside of a machine part or the floor of an automobile. The blocking agent must be dissociated at the heatable temperature. In this case, from the viewpoint of low dissociation temperature, it is desirable to use compounds of oximes and amines as blocking agents, and among them, 3,5-dimethylpyrazole is preferably used.

  “Polyamide” as an adhesion-imparting agent is obtained by reacting a polybasic acid such as an aliphatic diamine such as hexamethylene diamine or an aromatic diamine with a polybasic acid, specifically, linole. A reaction product of polymerized fatty acid such as dimer acid or trimer acid and polyamine obtained by thermally polymerizing unsaturated fatty acid such as acid and the like is used. As this kind of adhesion-imparting agent, any amino compound having active hydrogen may be used, and aliphatic diamines and the like can also be used. However, since these are volatile and toxic, the polyamide is used here. Is used.

  Furthermore, according to the combined system of blocked isocyanate and polyamide as the adhesion-imparting agent, the viscosity of the coating film of the plastisol composition is reacted by the reaction between the isocyanate component regenerated during the heat-curing after coating and the amine. Can be improved and the coating film can be provided with excellent adhesion, and the adhesion to the coating can be improved.

  Further, the “epoxy resin” as the adhesion-imparting agent may be any one as long as it contains two or more epoxy groups in the molecule, such as bisphenol A diglycidyl ether type epoxy resin, novolac type epoxy resin, fat Cyclic epoxy resins, glycidyl ester type epoxy resins, linear aliphatic epoxy resins and the like are used. Moreover, this epoxy resin can also be made into various modified types modified with rubber such as NBR in order to impart flexibility.

And the plastisol composition concerning this Embodiment is prepared by mixing and stirring these compounding components with a well-known various mixing disperser.
Specific examples of the plastisol composition mixer / disperser include planetary mixers, kneaders, attritors, glen mills, rolls, and dissolvers.

  Furthermore, the plastisol composition according to this embodiment prepared in this manner is necessary by a known coating method, that is, by applying means such as brush coating, roller coating, air spray coating, electrostatic coating, and airless spray coating. A coating film is formed by applying to any place in an arbitrary thickness and coating form and heating to a predetermined temperature using a hot air circulating drying furnace or the like. Among the above-mentioned application means, if it is intended to obtain the desired coating film thickness on the coating line side of automobile manufacture, airless spray coating that can obtain a thick film in a short time is most suitable. The coating includes improved ones such as electrostatic airless spray coating and air-assisted airless spray coating. And, in the painting line of the automobile production line, when applying to the steel sheet surface in the floor under such as the under floor part and the foil house part, the electrodeposition coating film of the steel sheet after finishing the degreasing process, the chemical conversion treatment process and the electrodeposition coating process. It can apply | coat to the surface of this by the said airless spray coating method etc. By the way, as spray application to panels such as under floor parts of automobiles, wheel houses, etc., seal spray application is performed on the panel joints for the purpose of waterproofing and dustproofing, and chipping resistance and vibration suppression are imparted to the general panel surface. There is surface spray coating performed for the purpose, and usually, seal spray coating is performed first, and then surface spray coating is performed from there. Therefore, since both layers are applied in an overlapping manner, compatibility between the two layers before drying (at the time of application) and adhesion after drying are required. For this reason, the coating agents used for seal spray coating and surface spray coating are the same system. However, since the plastisol composition of the present embodiment can be applied to both seal spray coating and surface spray coating, the storage tank, piping, coating equipment, etc. Excellent. When the plastisol composition of the present embodiment is used for both seal blowing and surface blowing, it is preferable to perform surface blowing while the seal blowing surface is in a wet state and heat cure both at the same time.

In addition, when applying for undercoats such as underfloor parts and foil houses, heat curing after applying plastisol composition is usually a drying and baking process for intermediate coating and top coating in automobile coating processes. It is recommended to be performed at the same time. For example, when coating is applied to the lower body structure of the vehicle body, the plastisol composition according to the present embodiment is applied to the object to be coated, for example, 70 to 120 ° C. or higher. After preheating and pre-curing at this temperature, it is heat-cured together with baking and curing (generally 120 to 140 ° C.) of the intermediate coating or top coating to be overcoated on the coating film.
Of course, the above-mentioned painting means can also be painted by a computer-controlled automatic painting machine or a robot painting machine.

  In the coating film formed in this way, vibration damping is promoted mainly by the aromatic ester having a phenyl group and / or a sulfone group as the first component, and has a phenyl group and a sulfone group as the second component. Since the promotion of plasticization of the thermoplastic resin is efficiently achieved by the non-aromatic ester, it has both chipping resistance and vibration suppression. Not only can it be suitably used for floor unders such as parts, wheelhouses, rocker panel parts, front parts, rear fender parts, front apron parts, etc. Tunnel upper in the center of the floor, floor uppers such as door panels, side sill parts, side surfaces such as the lower part of doors, and automobiles Also construction the sealing or the like of the steel plate joint, it is widely construction possible.

  Therefore, in the automobile, by using the plastisol composition according to the present embodiment that can form a coating film having vibration damping properties in addition to chipping resistance, the vibration damping material applied to the conventional floor upper can be obtained. This can reduce the weight of the coating film on the automobile and contribute to the weight reduction of the automobile.

Incidentally, sheet-like damping materials such as asphalt sheets that have been installed on conventional floor uppers add weight and are difficult to attach to parts with complex shapes, and are installed for each vehicle type. It must be cut into a predetermined size and shape according to the shape of the part to be applied, or in some cases three-dimensionally molded, and moreover, it is difficult to automate the pasting work and is troublesome and enormous. It took man-hours.
On the other hand, the plastisol composition of the present embodiment is of a coating type that can form a coating film having both chipping resistance and vibration damping properties when applied, and the prepared composition has appropriate flexibility. Therefore, it can follow a part having a step and can be used in a wide range, and can be automated by a painting robot, thereby shortening the process time.

  In addition, the plastisol composition of the present embodiment includes a stabilizer, a pigment, a hygroscopic agent, a thickener, an antioxidant, an ultraviolet absorber / decomposition agent, a diluent, a curing agent, a leveling agent, and anti-sagging as necessary. Additives such as an additive, an auxiliary resin, an organic solvent, a flame retardant, a rust inhibitor, and an anti-aging agent can be added.

Examples of stabilizers include epoxy stabilizers, plastisol stabilizers such as metal soaps, inorganic acid salts, and organometallic compounds. Among these, organotin compounds such as dibutyltin dilaurate, tribasic Lead sulfate and the like are typical, and when a blocked isocyanate is used as an adhesiveness-imparting agent, these also act as a catalyst for promoting dissociation of the blocking agent during bake hardening.
Examples of pigments include colored inorganic pigments that also serve as extender pigments such as titanium oxide and carbon black, and organic pigments such as azo-based and phthalocyanine-based pigments. Examples of hygroscopic agents include calcium oxide and magnesium oxide. Examples of the thickener include organic bentonite, etc., as the antioxidant, for example, an antioxidant such as phenol and amine can be used, and as the ultraviolet absorber / decomposer, benzotriazole, etc. As the diluent, for example, solvents such as xylene and mineral terpenes can be used.

Further, the curing agent is used to cure the resin used for the adhesion imparting agent, and for example, powder amines such as hydrazide compounds, aliphatic polyamines, aromatic polyamines, etc. are used. Hydrazide compounds such as acid dihydrazide (ADH) and sebacic acid dihydrazide (SDH) can be suitably used because they are cured at a relatively low temperature and have good storage stability. Incidentally, when a block-type urethane resin is used as the adhesiveness imparting agent, the hydrazide compound promotes dissociation of the block agent bonded to the block-type urethane resin and reacts with the urethane resin. As a result, the hydrazide compound forms a urea bond with the urethane resin, and this urea bond can improve the durability of the coating film of the plastisol composition and the adhesion between the coating film and the coating object.
In addition, the leveling agent is used to improve the leveling property (smoothing property) of the coating film. For example, a silicon resin, a high viscosity type or a low viscosity type dimer acid-modified epoxy resin, etc. can be used. One anti-sagging agent is used to prevent sagging of the coating film by adjusting the viscosity (thixotropic properties) of the composition while balancing with other components, and it contains ultra-fine calcium carbonate, fine-particle silica, etc. The auxiliary resin is used to assist the purpose of improving the chipping resistance. For example, resins such as urethane resin, polybutadiene, isoprene, NBR, chloroprene and EVA can be used. The organic resin is used for viscosity adjustment for improving the coating workability, and a high boiling point organic solvent or the like can be used.

Next, examples of the plastisol composition according to the embodiment of the present invention will be specifically described.
In this embodiment, an acrylic resin or vinyl chloride (PVC) resin is used as the thermoplastic resin, and an alkylbenzyl phthalate or alkylsulfonic acid of an aromatic ester having a phenyl group and / or a sulfonic group as the first component plasticizer. A phenyl ester and a dialkyl phthalate of an aromatic ester having no phenyl group and sulfone group as a second component plasticizer were used in combination. Further, mica was used as a filler, blocked isocyanate was used as an adhesion promoter, and powdered amine was added as a curing agent.
These are blended and prepared as shown in Table 1 to prepare various plastisol compositions (Examples 1 to 4), and the plastisol compositions according to each blend are evaluated for chipping resistance and vibration damping. It was.

More specifically, in Example 1, 155 parts by weight of an acrylic resin (“DEGALAN UC508” manufactured by Kaneka Corporation) as a thermoplastic resin and butylbenzyl phthalate (BBP) as an alkylbenzyl phthalate as a first component plasticizer : Daihachi Chemical Industry Co., Ltd.) 37 parts by weight, diisononyl phthalate (DINP: Jay Plus Co., Ltd.) which is a dialkyl phthalate as the second component plasticizer, and mica 120 parts by weight as filler. Part, 50 parts by weight of a block type urethane resin as an adhesion-imparting agent, and 5 parts by weight of powdered amine as a curing agent were blended to obtain a plastisol composition according to Example 1.
In Example 2, 37 parts by weight of benzyl phthalate having 7 to 9 carbon atoms of alkyl group which is alkylbenzyl phthalate as the first component plasticizer (OBP equivalent: “Santisizer S261A” manufactured by Ferro Japan Co., Ltd.) A plastisol composition according to Example 2 was obtained in the same manner as Example 1 except that it was blended.
Example 3 is the same as Example 1 except that 37 parts by weight of alkylsulfonic acid phenyl ester (“Mezamol” manufactured by LANXESS Co., Ltd .; Mesamoll is a trademark) is blended as a plasticizer of the first component. A plastisol composition according to 3 was obtained.
In Example 4, 155 parts by weight of a vinyl chloride resin (“Luron paste” manufactured by Tosoh Corporation) as a thermoplastic resin, and an alkyl group which is alkylbenzyl phthalate as a first component plasticizer has 7 to 7 carbon atoms. Example 4 was carried out in the same manner as in Example 1, except that 24 parts by weight of 9 benzyl phthalate (equivalent to OBP) and 24 parts by weight of diisononyl phthalate (DINP) as a second component plasticizer were blended. A plastisol composition was obtained.

  Chipping resistance is obtained by dropping a nut from a predetermined height onto a specimen of a plastisol composition in which Examples 1 to 4 thus obtained are applied to an electrodeposited steel sheet with a thickness that is actually used. Sexuality was evaluated. The evaluation result is determined based on the total weight of the nuts dropped, and even if the nuts are dropped more than 30 kg, no hole reaching the electrodeposition coated steel sheet is marked as ◯.

In addition, the evaluation of vibration damping was performed by measuring the secondary resonance frequency by a cantilever beam method on a plastisol composition test specimen obtained by applying a plastisol composition to an electrodeposited steel sheet so that the surface density is 6 kg / m ^2. The loss factor at each measured temperature (−20 ° C., 0 ° C., 20 ° C., 40 ° C., 60 ° C.) that falls within the outside air temperature range where the vehicle travels was calculated by the half-width method. In Table 1 described later, a loss factor of 0.09 or more at a measurement temperature of 20 ° C. was determined to be “good”.

Furthermore, for comparison, various plastisol compositions according to Comparative Examples 1 to 3 were prepared, and the chipping resistance and vibration damping properties were also evaluated.
The plastisol compositions of Comparative Example 1 and Comparative Example 2 are those in which only diisononyl phthalate (DINP), which is a dialkyl phthalate, is blended in a plasticizer, and corresponds to a conventional general anti-chipping coating. Moreover, in Comparative Example 3, although the above-mentioned OBP equivalent was blended with diisononyl phthalate (DINP) and alkyl benzyl phthalate, which are dialkyl phthalates, as a plasticizer, a plastisol composition was blended without blending an adhesion-imparting agent and a curing agent. It was produced.
Table 1 shows the evaluation results of the above-mentioned blending compositions (Examples 1 to 4 and Comparative Examples 1 to 3) and their chipping resistance and vibration damping properties. In addition, FIG. 1 shows a graph of measurement results of loss factors regarding the vibration damping properties of the plastisol compositions of Examples 1 to 4 and Comparative Examples 1 to 3. In addition, the numerical value of the upper stage of Table 1 shows each compounding component of the plastisol composition of Example 1 thru | or Example 4 and Comparative Example 1 thru | or Comparative Example 3 by the weight part.

As can be seen from the results in Table 1 and FIG. 1, the plastisol compositions of Comparative Examples 1 and 2 using only a dialkyl phthalate as a plasticizer, which corresponds to a conventional anti-chiping paint, ensure chipping resistance. Although it is possible, the loss factor is small in the outside air temperature range in the range of −20 ° C. to 60 ° C. where the vehicle travels, and the vibration damping property is insufficient.
In contrast, as plasticizers, alkylbenzyl phthalate (equivalent to BBP or OBP) of an aromatic ester having a phenyl group and / or a sulfone group or an alkylsulfonic acid phenyl ester, and an aromatic ester having no phenyl group and a sulfone group In the plastisol compositions of Examples 1 to 4 which are used in combination with dialkyl phthalate (DINP), high chipping resistance is ensured, and the outside of the range of −20 ° C. to 60 ° C. where the vehicle travels is ensured. Compared with the plastisol compositions of Comparative Example 1 and Comparative Example 2 at any measured temperature in the temperature range, the loss factor is high and high vibration damping properties are exhibited. In particular, since the loss factor is 0.07 or more at a measurement temperature of 0 ° C. and the loss factor is 0.09 or more at a measurement temperature of 20 ° C., the vibration damping property is excellent in a temperature range of 0 ° C. to 20 ° C. ing.

  As described above, in the plastisol compositions of Examples 1 to 4, the results satisfying both the chipping resistance and the vibration damping property were obtained from the alkyl of an aromatic ester having a phenyl group and / or a sulfone group. By using benzyl phthalate (equivalent to BBP or OBP) or alkyl sulfonic acid phenyl ester and dialkyl phthalate (DINP) of an aromatic ester not having a phenyl group and a sulfone group, the coating film has a characteristic that exhibits appropriate strength. This is because the chipping resistance is ensured and the vibration damping characteristics are improved.

  In Comparative Example 3 in which no adhesion-imparting agent and no curing agent were blended, the alkylbenzyl phthalate (corresponding to OBP) of an aromatic ester having a phenyl group and / or a sulfone group, a phenyl group and a sulfone as a plasticizer. Although an aromatic ester dialkyl phthalate (DINP) having no group is used in combination, both the chipping resistance and the vibration damping property are not satisfied. This is because the adhesiveness-imparting agent and the curing agent are not blended, so that sufficient adhesion (adhesion) to the object to be coated was not obtained, so that the chipping resistance was not exhibited in the formed coating film. It is thought.

As described above, in the plastisol composition of this example, alkylbenzyl phthalate or alkylsulfonic acid phenyl ester as the first component of the aromatic ester having a phenyl group and / or a sulfone group in the plasticizer, the phenyl group and By using a dialkyl phthalate together with the second component of the aromatic ester having no sulfone group, the vibration damping is promoted mainly by the first component of the aromatic ester having a phenyl group and / or a sulfone group. In addition, the second component of the aromatic ester having no sulfone group efficiently promotes plasticization of the thermoplastic resin, and appropriately controls the plasticization characteristics of the thermoplastic resin to prevent chipping and vibration suppression. It is possible to form a coating film that satisfies both properties. Further, when these are used in combination, the ratio between the first component and the second component can be freely controlled. Therefore, the balance between the chipping resistance and the vibration damping property is controlled, and both can be easily adjusted.
And in addition to chipping resistance, it also has vibration damping properties, so it can reduce the vibration damping material applied to the conventional floor upper, reduce the weight of the entire automobile coating film, Can contribute to weight reduction.

In addition, in the plastisol composition of the above-described example, an example in which it is embodied as an undercoat composition used for an underfloor part of a car or a wheel house part has been described. It is not limited to an example, The kind and mixture ratio of a thermoplastic resin, a plasticizer, a filler, an adhesiveness imparting agent, and other components can be changed variously. In particular, since the first component of the aromatic ester having a phenyl group and / or sulfone group and the second component of the aromatic ester having no phenyl group and sulfone group are used in combination with the plasticizer, the first component and the second component By freely controlling the ratio of the two components, it is possible to easily adjust both chipping resistance and vibration damping.
Further, the plastisol composition of the present embodiment can be advantageously applied not only to the automobile body, but also to vehicles other than automobiles such as railways, home appliances, houses, and the like.

Furthermore, when implementing this invention, it is not limited to the said Example about the structure of another part of a plastisol composition, a component, a mixing | blending, a manufacturing method, etc.
The numerical values given in the embodiments and examples of the present invention are not all critical values, and certain numerical values indicate preferred values suitable for implementation, so the numerical values are slightly changed. However, it does not deny the implementation.

Claims (4)

A plastisol composition comprising at least a thermoplastic resin, a plasticizer, a filler, and an adhesion-imparting agent,
The plasticizer is a combination of a first component of an aromatic ester having a phenyl group and / or a sulfone group and a second component of an aromatic ester having no phenyl group and a sulfone group. A plastisol composition characterized by the above.   The plastisol composition according to claim 1, wherein the first component is alkylbenzyl phthalate and / or alkylsulfonic acid phenyl ester, and the second component is dialkyl phthalate.   The plastisol composition according to claim 1 or 2, wherein an acrylic resin and / or a vinyl chloride resin is used as the thermoplastic resin.   The plastisol composition according to any one of claims 1 to 3, wherein the adhesiveness imparting agent is one or more of blocked isocyanate, polyamide, and epoxy resin.

Images