JP5493239B2 - Aqueous resin dispersion and method for producing the same - Google Patents

Description

  The present invention relates to an aqueous dispersion containing a propylene polymer and a method for producing the same.

  Propylene polymers such as propylene polymers and propylene-α-olefin copolymers are inexpensive and used in a wide range of fields because of their excellent mechanical properties, heat resistance, chemical resistance, and water resistance. Has been. However, such a propylene polymer generally has a low polarity because it does not have a polar group in the molecule, and it is difficult to paint or adhere to it. For this reason, various methods such as chemically treating the surface of a molded product of a propylene-based polymer with a chemical or the like, and oxidizing the surface of the molded product by a method such as corona discharge treatment, plasma treatment, or flame treatment are attempted. It has been. However, in these methods, not only a special apparatus is required but also the effect of improving paintability and adhesiveness is not always sufficient.

  Therefore, as a device for imparting good paintability and adhesiveness to the propylene polymer by a relatively simple method, so-called chlorinated polypropylene, acid-modified propylene-α-olefin copolymer, and further acid-modified chlorinated polypropylene are used. Has been developed. Such a modified propylene polymer is applied as a surface treatment agent, an adhesive, a paint or the like to the surface of a molded body such as polypropylene. The modified propylene polymer is usually applied in the form of a solution of an organic solvent or a dispersion in water, but in recent years, an aqueous dispersion has come to be preferably used from the viewpoint of safety and hygiene and environmental pollution. Yes.

  For example, an aqueous resin in which acid-modified chlorinated polypropylene is made aqueous using a surfactant and a basic substance (Patent Document 1) or an aqueous resin in which acid-modified polyolefin is made aqueous using a surfactant and a basic substance (Patent Documents 2 and 3). However, in these methods, it is necessary to add a large amount of a surfactant in order to reduce the dispersed particle size. As a result, there is a problem that paints using such an aqueous dispersion have poor water resistance and chemical resistance. there were. Further, the surfactant may bleed out to the painted surface after coating, resulting in poor appearance, and further improvement has been desired.

  In recent years, lowering of the drying temperature and baking temperature of the coating film has been desired due to environmental load and energy problems. In organic solvent-based coating agents, high-crystalline and low-crystalline polyolefin modified products are used so that high adhesion can be obtained even when low-temperature baking at about 60 to 80 ° C. is performed on polyolefin-based resin substrates. A coating agent contained at a specific ratio has been proposed (Patent Documents 4 and 5).

However, water-based coating agents use water-based resins, so there is a problem of poor drying properties compared to organic solvent-based coating agents. Propylene-based polymers generally have a high melting point, so film-forming properties at low temperature baking are sufficient. However, it was difficult to achieve high adhesion by low temperature baking. For this reason, there has been a demand for an aqueous resin dispersion that exhibits high adhesion to a polyolefin substrate under low temperature drying and baking conditions similar to those of organic solvent-based coating agents.
JP-A-3-182534 Japanese Patent Laid-Open No. 6-256592 JP 2004-002842 A JP 7-331159 A JP 2006-104430 A

  The present invention provides an aqueous resin dispersion that is excellent in drying property at low temperature baking, film formability, adhesion to a propylene-based polymer substrate, and useful as an adhesive, primer, paint, ink, etc. for an olefin-based polymer. The manufacturing method is provided.

As a result of intensive studies to achieve the above object, the present inventors have found that a specific low melting point and low molecular weight propylene-based polymer modified with an unsaturated organic acid derivative, and also modified with an unsaturated organic acid derivative. It was found that the aqueous resin dispersion combined with a specific high melting point and high molecular weight propylene-based polymer had specific excellent properties, and the present invention was achieved.
That is, the present invention provides an aqueous resin dispersion in which a modified propylene polymer obtained by modifying the following propylene polymers (A1) and (A2) with an unsaturated organic acid derivative is dispersed in water. The saturated organic acid derivative is at least one selected from the group consisting of an unsaturated carboxylic acid and an unsaturated dicarboxylic anhydride, and is modified with the unsaturated organic acid derivative (A1) and / or ( The present invention relates to an aqueous resin dispersion, wherein A2) is bonded to a polyether resin having a polyalkylene structure.
(A1): Propylene polymer having no melting point or a melting point of less than 75 ° C. and a weight average molecular weight of 10,000 to 100,000
(A2): a propylene polymer having a melting point of 70 ° C. or higher and lower than 120 ° C., a weight average molecular weight of 100,000 to 500,000, and 1.5 times or more of the weight average molecular weight of (A1).

The present invention also relates to an aqueous resin dispersion containing the polymers (A1) and (A2) at (A1) :( A2) = 10: 90 to 90:10 (weight ratio).
The present invention also relates to an aqueous resin dispersion in which the polymers (A1) and (A2) are mixed and then modified with an unsaturated organic acid derivative.
The present invention also relates to an aqueous resin dispersion in which the polymers (A1) and (A2) are each modified after being modified with an unsaturated organic acid derivative.
The present invention also relates to an aqueous resin dispersion obtained by graft-bonding the polyether resin to the polymer (A1) and / or (A2).

Furthermore, the present invention provides a method for producing the aqueous resin dispersion, wherein the propylene polymers (A1) and (A2) are mixed, then modified with an unsaturated organic acid derivative, and a polyether resin is bonded thereto. , then a process for producing an aqueous resin dispersion, which comprises dispersing in water.
Furthermore, the present invention provides a method for producing the aqueous resin dispersion, wherein the propylene polymers (A1) and (A2) are each modified after being modified with an unsaturated organic acid derivative, and a polyether resin is bonded thereto. , then a process for producing an aqueous resin dispersion, which comprises dispersing in water.

  The aqueous resin dispersion of the present invention has an advantage that it is excellent in drying property and film forming property at low temperature baking. The resulting film shows good adhesion to polyolefin substrates, especially propylene polymer substrates, and is also formed on difficult-to-adhere substrates such as untreated polypropylene, which are usually difficult to paint or bond. Yes. This film is further excellent in solvent resistance (oil resistance, GH resistance), chemical resistance, water resistance, and moisture resistance. Further, when the polymer of the present invention is used in combination with other resins to form a composite aqueous resin dispersion, the physical property values derived from other resins are improved, specifically, the strength, water resistance, weather resistance, Rubability, solvent resistance, etc. can be improved.

Therefore, the aqueous resin dispersion of the present invention is extremely useful as an adhesive, a surface treatment agent, a coating agent, a paint, an ink and the like for a crystalline polyolefin-based substrate.
Since the coating agent using the aqueous resin dispersion of the present invention has characteristics comparable to those of an organic solvent-based coating agent, it can be used for applications that have been conventionally applied as a solution of an organic solvent, and is preferable in terms of safety and hygiene. Further, since it is not an organic solvent solution, VOC (volatile organic chemical substance) emission can be reduced, which is preferable from the environmental viewpoint. Furthermore, an aqueous resin dispersion having excellent properties can be obtained without substantially containing chlorine. When chlorine is not included, there are no problems such as dioxin and toxicity, which is very preferable in terms of environment.

  Among these, if the propylene polymer of the preferred embodiment of the present invention described later is used, a modified propylene polymer having excellent water dispersibility can be obtained, so that the dispersed particle size is fine and stable. There is an advantage that a dispersed aqueous resin dispersion can be obtained. And since it can disperse | distribute without adding surfactant substantially, there exists an advantage which can suppress the bleed-out by the surfactant which was a problem conventionally, and the coated article of the outstanding external appearance is obtained.

Further, according to the method for producing an aqueous resin dispersion of the present invention, an excellent aqueous resin dispersion exhibiting excellent dryness and film formability at low temperature baking and good adhesion to a propylene-based polymer substrate is obtained. It can be easily obtained.
In the present invention, it is not always essential to exhibit all the effects, and it is only necessary to have one or more of the effects described above.

The aqueous resin dispersion of the present invention is characterized in that a modified propylene polymer obtained by modifying the following propylene polymers (A1) and (A2) with an unsaturated organic acid derivative is dispersed in water. .
(A1): Propylene polymer having no melting point or a melting point of less than 75 ° C. and a weight average molecular weight of 10,000 to 100,000 (A2): melting point of 70 ° C. or more and less than 120 ° C., weight Propylene polymer having an average molecular weight of 100,000 to 500,000 and not less than 1.5 times the weight average molecular weight of (A1) That is, a low melting point and low molecular weight propylene polymer (A1) is not used. Dispersed in water are a modified propylene polymer modified with a saturated organic acid derivative and a modified propylene polymer obtained by modifying a high melting point and high molecular weight propylene polymer (A2) with an unsaturated organic acid derivative. Being done. In the present invention, the term “dispersion” is a concept including a state in which dispersed particles are extremely small and dispersed in a single molecule, and a state that can be said to be substantially dissolved.

  The reason why an excellent aqueous resin dispersion can be obtained by the combined use of the polymers (A1) and (A2) is not necessarily clear, but by including a low melting point and low molecular weight propylene polymer (A1), at a relatively low temperature. It is considered that the resin particles are easily melted, and the resin particles are melted at a low drying temperature and a low baking temperature to form a film, thereby improving the adhesion to the polyolefin-based substrate. And it is thought that the high melting point and high molecular weight propylene polymer (A2) increases the strength of the coating film and contributes to cohesion, water resistance, solvent resistance and the like.

The propylene polymer (A1) of the present invention has no melting point or a melting point of less than 75 ° C. Necessary for improving adhesion in low-temperature baking. Preferably, there is no melting point or the melting point is less than 70 ° C. Although there is no lower limit of the melting point, it is usually preferably 50 ° C. or higher.
In the present invention, the melting point of the propylene polymer is determined by the following method using a thermal analysis system (DSC-7) manufactured by PerkinElmer. A sample (about 5 to 10 mg) was melted at 160 ° C. for 3 minutes, cooled to −20 ° C. at a rate of 10 ° C./minute, held at −20 ° C. for 2 minutes, and then increased to 160 ° C. at 10 ° C./minute. The melting curve was obtained by heating, and the peak top temperature of the main endothermic peak in the final temperature rising stage was determined as the melting point. In the present invention, “no melting point” refers to a state in which no clear endothermic peak having an endothermic amount of 0.5 J / g or more is observed in the range of 0 ° C. to 160 ° C. by the above measurement method.

  The weight average molecular weight of the propylene polymer (A1) of the present invention is 10,000 to 100,000. In order to improve the adhesiveness in low temperature baking, it is necessary to make it 100,000 or less. A preferable upper limit is 80,000, more preferably 70,000, and still more preferably 60,000. On the other hand, in order to keep the coating film strength strong and increase the adhesive strength, it is necessary to set it to 10,000 or more. A preferred lower limit is 20,000, more preferably 30,000. The weight average molecular weight in the present invention is a value measured by GPC (Gel Permeation Chromatography) and converted with a calibration curve of each propylene polymer. And can be carried out by a conventionally known method.

In general, the molecular weight is lowered by the modification with the unsaturated organic acid derivative as compared with that before the modification, but the weight average molecular weight after the modification of the unsaturated organic acid derivative of the propylene polymer (A1) is also preferably within the above range. .
The propylene polymer (A2) of the present invention has a melting point of 70 ° C. or higher and lower than 120 ° C. In order to increase the strength of the coating film and to have high water resistance, solvent resistance, etc., it is necessary to set it at 70 ° C. or higher. Preferably, the melting point is higher than that of the polymer (A1). More preferably, the lower limit is 75 ° C. On the other hand, in order to perform baking at low temperature, it is necessary to set it to less than 120 degreeC. A preferable upper limit is less than 110 ° C, more preferably less than 100 ° C, and still more preferably less than 90 ° C.

  The weight average molecular weight of the propylene polymer (A2) of the present invention is 100,000 to 500,000. In order to increase the strength of the coating film and to have high water resistance, solvent resistance, etc., it is necessary to set it to 100,000 or more. A preferred lower limit is 120,000, more preferably 150,000. On the other hand, in order to perform baking at low temperature, it is necessary to make it 500,000 or less. A preferred upper limit is 400,000, more preferably 300,000.

  The weight average molecular weight Mw2 of (A2) is 1.5 times or more the weight average molecular weight Mw1 of (A1). In order to obtain a coating film having high strength and high adhesive strength and solvent resistance, the ratio (Mw2 / Mw1) of the weight average molecular weight of both needs to be 1.5 times or more. Preferably it is 2 times or more, more preferably 3 times or more. There is no particular upper limit value for (Mw2 / Mw1), but it is preferably 20 times, more preferably 15 times. The smaller the upper limit value, the easier the drying and baking at a lower temperature.

  The weight average molecular weight after modification with the unsaturated organic acid derivative of the propylene-based polymer (A2) may be somewhat lower than before modification. Usually, it is 50,000 or more, preferably 60,000 or more, more preferably 80,000 or more, and further preferably 100,000 or more. However, it is usually 250,000 or less, preferably 200,000 or less, more preferably 150,000 or less.

  When the polymers (A1) and (A2) are mixed and then modified with an unsaturated organic acid derivative, the weight average molecular weight of the resulting modified propylene polymer mixture may be 30,000 or more. preferable. More preferably, it is 50,000 or more. The larger the lower limit value, the stronger the coating film strength, and the higher the adhesive strength. However, it is preferably 150,000 or less, more preferably 120,000 or less, and still more preferably 100,000 or less. The smaller the upper limit value, the easier the drying and baking at a lower temperature.

When modification is carried out after mixing, the molecular weight distribution of the resulting modified propylene polymer mixture does not necessarily show a bimodal shape with two peaks in the high molecular weight region and the low molecular weight region, and separation is not possible. The peak may have an insufficient shoulder peak. When the molecular weights of (A1) and (A2) are close to each other, only one peak may be observed.
On the other hand, when the polymers (A1) and (A2) are each modified with an unsaturated organic acid derivative and then mixed, the high molecular weight range, which is the sum of the molecular weight distributions of the above (A1) and (A2), is generally low. It shows a bimodal shape with two peaks in the molecular weight range.

  The combined ratio of the polymers (A1) and (A2) is preferably in the range of (A1) :( A2) = 10: 90 to 90:10 by weight ratio. The total amount of the polymers (A1) and (A2) is 100 parts by weight, the amount of the polymer (A1) is 10 parts by weight or more and 90 parts by weight or less, and the amount of the polymer (A2) is 10 parts by weight. The amount is 90 parts by weight or less. In order to increase the adhesion to the substrate during low-temperature baking, it is preferable that the amount of the polymer (A1) is large. More preferably, the amount of the polymer (A1) is 30 parts by weight or more, and more preferably 50 parts by weight or more. On the other hand, in order to improve the strength, water resistance, weather resistance, abrasion resistance, solvent resistance, and blocking resistance of the coating film, it is preferable to reduce the amount of the polymer (A1). More preferably, the amount of the polymer (A1) is 85 parts by weight or less, and more preferably 80 parts by weight or less.

  In the present invention, the form is not particularly limited as long as the polymers (A1) and (A2) are modified with an unsaturated organic acid derivative and uniformly dispersed in water. For example, there is a method in which the polymers (A1) and (A2) are mixed and then modified with an unsaturated organic acid derivative. In this case, an aqueous resin dispersion in which particles in which the polymers (A1) and (A2) are mixed in the same particle is dispersed in water is obtained. The polymers (A1) and (A2) may be synthesized and then modified by mixing by melt kneading and the like, and emulsified and dispersed in water.

Alternatively, there is also a method in which the polymers (A1) and (A2) are each modified with an unsaturated organic acid derivative and then mixed. The particles made of the polymer (A1) and the particles made of (A2) are separately formed to obtain an aqueous resin dispersion dispersed in water.
The purpose, cost, etc. may be selected according to need, but it is usually simpler to mix the polymers (A1) and (A2) and then modify with an unsaturated organic acid derivative, The dispersed particle size tends to be slightly smaller.

The polymer (A1) and / or (A2) is preferably further bonded to the hydrophilic polymer (B) after being modified with the unsaturated organic acid derivative. Since the hydrophilicity of the polymer is increased, there is an advantage that an aqueous resin dispersion having a finer particle diameter can be obtained. The bonding form is not particularly limited, but is preferably a graft bond.
This will be described in more detail below.

[1] Propylene-based polymer Propylene-based polymers (A1) and (A2) may be basically the same except for the molecular weight and melting point, and both will be described below.
Various known propylene polymers can be used as the propylene polymer, and are not particularly limited. For example, propylene homopolymer, propylene and other comonomers such as ethylene, butene-1, pentene-1, A copolymer with at least one selected from α-olefin comonomers having 2 or more carbon atoms such as hexene-1, heptene-1, octene-1, cyclopentene, cyclohexene, and norbornene can be used. The α-olefin comonomer is preferably an α-olefin comonomer having 2 to 8 carbon atoms, and more preferably an α-olefin comonomer having 2 to 6 carbon atoms.

  A copolymer of propylene and a comonomer such as vinyl acetate, acrylic acid ester, or methacrylic acid ester can also be used. In addition, when only calling it a copolymer, it may be a random copolymer or a block copolymer. Furthermore, a chlorinated propylene polymer obtained by chlorinating these propylene polymers can also be used. The chlorination degree of the chlorinated propylene polymer is usually 5% by weight or more, preferably 10% by weight or more, and the chlorination degree is usually 50% by weight or less, preferably 30% by weight or less. However, the most preferable form is that the propylene skeleton is substantially free of chlorine in terms of environmental load and adhesion to the polyolefin substrate.

  Specifically, for example, polypropylene, ethylene-propylene copolymer, propylene-butene copolymer, ethylene-propylene-butene copolymer, propylene-hexene copolymer, chlorinated polypropylene, chlorinated ethylene-propylene copolymer And a chlorinated propylene-butene copolymer. Preferably, it is a propylene homopolymer or a copolymer of propylene and another α-olefin, and these may be chlorinated. More preferably, propylene homopolymer, ethylene-propylene copolymer, propylene-butene copolymer, ethylene-propylene-butene copolymer, chlorinated polypropylene, chlorinated ethylene-propylene copolymer, or chlorinated propylene- It is a butene copolymer. More preferred are propylene homopolymer, ethylene-propylene copolymer, and propylene-butene copolymer. The propylene content of the propylene-based polymer is preferably 50 mol% or more, more preferably 60 mol% or more, and further preferably 70 mol% or more. Usually, the higher the propylene content, the higher the adhesion to the propylene-based polymer substrate.

These may be used individually by 1 type and may be used in combination of 2 or more type.
The propylene polymer may be linear or branched.
One of the most preferable forms of the propylene homopolymer or copolymer is that having an isotactic structure in whole or in part as stereoregularity. For example, not only ordinary isotactic polypropylene but also isotactic block polypropylene, stereo block polypropylene, etc., as described in JP-A No. 2003-231714 and US Pat. No. 4,522,982, can be used. .

Preferably, the propylene polymer (A1) is a stereoblock polypropylene homopolymer or copolymer having an isotactic block and an atactic block. Most preferred is a stereoblock polypropylene polymer having an isotactic block and an atactic block.
More preferably, in ¹³ C-NMR, a peak derived from the carbon atom of the methyl group of the propylene unit chain part consisting of a head-to-tail bond is observed, and the peak of the peak attributed to the pentad represented by mmmm is observed. When the chemical shift is 21.8 ppm, the ratio (S ₁ / S) of the peak area S ₁ having 21.8 ppm as the peak top to the total peak area S appearing from 19.8 ppm to 22.1 ppm is 20 % To 70%. A preferable value of the lower limit is 30%, more preferably 35%. A preferable value of the upper limit is 65%, more preferably 60%, and more preferably 55%. There is a tendency that the degree of stickiness becomes smaller as the value is lower than the lower limit, and the degree of crystallinity becomes lower and the preparation of the aqueous resin dispersion tends to become easier as the value is lower than the upper limit.

More preferably, 4 + 2S ₁ / S ₂ > 5, where S ₂ is an area of a peak (mmmmr) having a peak top of 21.5 to 21.7 ppm. As a method for measuring the pentad ratio, the method described in JP-A-2003-231714 can be used.
About the manufacturing method of the propylene-type polymer of this invention, if the polymer which satisfy | fills the requirements of this invention can be manufactured, it will not specifically limit, Any manufacturing method may be sufficient. For example, radical polymerization, cationic polymerization, anionic polymerization, coordination polymerization and the like may be mentioned, and each may be living polymerization.

In the case of coordination polymerization, for example, a method of polymerizing with a Ziegler-Natta catalyst or a method of polymerizing with a single site catalyst or a Kaminsky catalyst can be mentioned. A preferable production method includes a production method using a single site catalyst. This is because the molecular weight distribution and stereoregularity distribution of single-site catalysts are generally sharp due to the ligand design. As the single-site catalyst, for example, a metallocene catalyst or a Brookhart catalyst can be used, but it is preferable to use a metallocene catalyst from the viewpoint of narrow molecular weight distribution and easy control of stereoregularity distribution. C ₁ symmetric type metallocene catalyst, C ₂ symmetric, C _2V symmetric, C _S symmetric like, it may be selected preferred catalyst in accordance with the stereoregularity of polymerized propylene polymer. Preferably, a C ₁ symmetric type or C ₂ symmetric type metallocene catalyst can be used.

  The polymerization may be any polymerization form such as solution polymerization, slurry polymerization, bulk polymerization, and gas phase polymerization. In the case of solution polymerization or slurry polymerization, examples of the solvent include aromatic hydrocarbons such as toluene and xylene, aliphatic hydrocarbons such as hexane, heptane, octane and decane, and alicyclic aliphatics such as cyclohexane and methylcyclohexane. Hydrocarbons, halogenated hydrocarbons such as methylene chloride, carbon tetrachloride, chlorobenzene, esters such as methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, Examples thereof include alcohols such as methanol, ethanol, n-propanol, isopropanol and n-butanol, ethers such as dibutyl ether and tetrahydrofuran, and polar solvents such as dimethylformamide and dimethyl sulfoxide. Of these, aromatic hydrocarbons, aliphatic hydrocarbons, and alicyclic hydrocarbons are preferable, and toluene, xylene, hexane, heptane, cyclopentane, and cyclohexane are more preferable. These may be used individually by 1 type and may be used in combination of 2 or more type.

  The low melting point and low molecular weight propylene-based polymer (A1) of the present invention is usually an aromatic hydrocarbon-based organic solvent or a fat when using a metallocene catalyst as described in JP-A-2003-231714, for example. It can be obtained by polymerizing a monomer such as propylene in a group hydrocarbon organic solvent under high temperature conditions. On the other hand, the high melting point and high molecular weight propylene polymer (A2) is usually obtained by polymerizing a monomer such as propylene under a temperature lower than that of (A1).

[2] Modified Propylene Polymer Hereinafter, a propylene polymer modified with an unsaturated organic acid derivative is referred to as an unsaturated organic acid modified propylene polymer. An unsaturated organic acid derivative is a general term for an organic acid containing an unsaturated group, an esterified product thereof, an anhydride, or the like. The unsaturated organic acid derivative is preferably at least one selected from the group consisting of unsaturated carboxylic acids, dicarboxylic anhydrides, and dicarboxylic anhydride monoesters. It is preferable because it is highly reactive, has many unsaturated compounds having these groups, and can be easily copolymerized or graft-reacted to a propylene-based polymer, and can easily bind to a hydrophilic polymer described later. For example, (meth) acrylic acid, fumaric acid, maleic acid or its anhydride or anhydride monoester, itaconic acid or its anhydride or anhydride monoester, crotonic acid, styrenesulfonic acid and the like can be mentioned. Of these, maleic acid or its anhydride or anhydride monoester is preferred. These may be used individually by 1 type and may be used in combination of 2 or more type. (Meth) acrylic acid is a general term for acrylic acid and methacrylic acid.

The production method of the unsaturated organic acid-modified propylene polymer is not particularly limited. For example, a radically polymerizable compound having an organic acid group is graft-polymerized to a prepolymerized propylene polymer in the presence of a radical polymerization initiator. Can be obtained. In this case, a radical polymerizable unsaturated organic acid derivative is used.
The radical polymerization initiator used for the graft polymerization can be appropriately selected from ordinary radical initiators, and examples thereof include organic peroxides and azonitriles. Examples of organic peroxides include peroxyketals such as di (t-butylperoxy) cyclohexane, hydroperoxides such as cumene hydroperoxide, dialkyl peroxides such as di (t-butyl) peroxide, and benzoyl peroxide. Diacyl peroxides such as oxides and peroxyesters such as t-butylperoxyisopropyl monocarbonate can be used. Examples of the azonitrile include azobisbutyronitrile and azobisisopropylnitrile. Of these, benzoyl peroxide and t-butylperoxyisopropyl monocarbonate are particularly preferred. These may be used individually by 1 type and may be used in combination of 2 or more type.

The use ratio of the radical polymerization initiator and the graft copolymer unit is usually in the range of radical polymerization initiator: graft copolymer unit = 1: 100 to 2: 1 (molar ratio). Preferably it is the range of 1: 20-1: 1.
The production method of the unsaturated organic acid-modified propylene polymer is not particularly limited as long as a polymer satisfying the requirements of the present invention can be produced, and any production method may be used. For example, solution modification method (method of reacting by heating and stirring in a solution), melt modification method (method of reacting by melting and heating and stirring without a solvent, or method of reacting by heating and kneading with an extruder), etc. It is done. As a solvent in the case of manufacturing in a solution, the solvent quoted by the manufacturing method of a propylene polymer can be used similarly.

The reaction temperature is usually 50 ° C. or higher and 300 ° C. or lower, and preferably in the range of 80 to 230 ° C. The reaction time is usually about 1 to 20 hours in the solution modification method, and the residence time is about 10 seconds to 10 minutes in the melt modification method.
Specific examples of the unsaturated organic acid-modified propylene polymer of the present invention include a maleic anhydride-modified propylene polymer and its chlorinated product, a maleic anhydride-modified ethylene-propylene copolymer and its chlorinated product, and maleic anhydride. Acid-modified propylene-butene copolymer and its chloride, maleic anhydride-modified ethylene-propylene-butene copolymer and its chloride, acrylic acid-modified propylene polymer and its chlorinated product, acrylic acid-modified ethylene-propylene copolymer Examples thereof include a coalescence and a chlorinated product thereof, an acrylic acid-modified propylene-butene copolymer and a chloride thereof. These may be used individually by 1 type and may be used in combination of 2 or more type. Of these, maleic anhydride-modified propylene polymer, maleic anhydride-modified ethylene-propylene copolymer, and maleic anhydride-modified propylene-butene copolymer are particularly preferable.

  The amount of the unsaturated organic acid group in the unsaturated organic acid-modified propylene polymer is preferably in the range of 0.01 to 5 mmol, that is, 0.01 to 5 mmol / g per 1 g of the propylene polymer. A more preferred lower limit is 0.03 mmol / g, and even more preferably 0.05 mmol / g. A more preferred upper limit is 1 mmol / g, and even more preferably 0.5 mmol / g. The higher the lower limit value, the greater the amount of organic acid binding and the more hydrophilic the polymer tends to decrease the dispersed particle size. The lower the upper limit value, the better the adhesion to the crystalline propylene polymer that is the substrate. The water resistance of the coating film tends to increase.

  In this invention, you may have another functional group in the range which does not injure the objective of this invention. Examples of the functional group include a carboxylic acid ester group, a hydroxyl group, an amino group, an epoxy group, an amide group, an isocyanate group, and a silyl machine. The content of these functional groups is preferably 2 mmol or less per 1 g of the propylene polymer, that is, 2 mmol / g or less. A more preferred upper limit is 1 mmol / g, and even more preferably 0.5 mmol / g. In order to maintain high adhesion to the polyolefin substrate, it is preferably less than the upper limit.

  These functional groups can be obtained by modifying a monomer having a radically polymerizable unsaturated group and a functional group at the same time as the unsaturated organic acid derivative, or in a propylene polymer modified beforehand with an unsaturated organic acid derivative. It can also be obtained by further modification. Specific examples of the monomer having a radical polymerizable unsaturated group and a functional group include (meth) acrylic acid alkyl ester, (meth) acrylic acid hydroxyethyl ester, meth) acrylic acid hydroxypropyl ester, and (meth) acrylic. Examples include acid dialkylaminoethyl ester, glycidyl (meth) acrylate, and (meth) acrylamide.

[3] The hydrophilic polymer the polymer (A1) and / or (A2), after being modified by an unsaturated organic acid derivative, it is preferable to further the combined hydrophilic polymer (B). Since the hydrophilicity of the polymer is increased, there is an advantage that an aqueous resin dispersion having a finer particle diameter can be obtained. The bonding form is not particularly limited, but is preferably a graft bond.

  In the present invention, the hydrophilic polymer means a polymer having an insoluble content of 1% by weight or less when dissolved in water at 25 ° C. at a concentration of 10% by weight. The hydrophilic polymer (B) is not particularly limited as long as the effects of the present invention are not significantly impaired, and any of synthetic polymers, semi-synthetic polymers, and natural polymers can be used. The hydrophilic polymer may have a reactive group.

  Although it does not specifically limit as a synthetic polymer, For example, a poly (meth) acryl resin, polyether resin, polyvinyl alcohol resin, polyvinylpyrrolidone resin etc. can be used. Examples of natural polymers include, but are not limited to, corn starch, wheat starch, sweet potato starch, potato starch, tapioca starch, rice starch and other seaweeds, seaweed such as agar, sodium alginate, gum arabic, tragacanth gum, konjac, etc. Mucilage, animal protein such as glue, casein and gelatin, fermentation mucilage such as pullulan and dextrin, and the like can be used. The semi-synthetic polymer is not particularly limited, and for example, starch such as carboxyl starch, cationic starch, and dextrin, viscose, cellulose such as methyl cellulose, ethyl cellulose, carboxymethyl cellulose, and hydroxyethyl cellulose can be used.

  Among these, a synthetic polymer that can easily control the degree of hydrophilicity and has stable characteristics is preferable. More preferred are acrylic resins such as poly (meth) acrylic resins, polyvinyl alcohol resins, polyvinylpyrrolidone resins, and polyether resins. These may be used individually by 1 type and may be used in combination of 2 or more type. Of these, polyether resins having a polyalkylene structure with high hydrophilicity are most preferable.

  The acrylic resin that can be used in the present invention is usually obtained by polymerizing an unsaturated carboxylic acid or its ester or anhydride by radical polymerization, anionic polymerization, or cationic polymerization. The bonding method with the modified propylene polymer is not limited, but, for example, a method in which radical graft polymerization is directly performed on the modified propylene polymer, a reactive group such as a hydroxyl group, an amino group, a glycidyl group, or an (anhydrous) carboxylic acid group. And a method of reacting an acrylic resin having a modified propylene polymer.

As the unsaturated carboxylic acid or ester or anhydride thereof exhibiting hydrophilicity, preferably, (meth) acrylic acid, hydroxyethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate (dimethylaminoethyl (meth) acrylate) Quaternized compounds and (meth) acrylamide are mentioned.
In addition, a hydrophobic radical polymerizable compound (hydrophobic monomer) can be copolymerized within a range showing hydrophilicity. Examples of the copolymerizable hydrophobic monomer include a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms, an aryl group or an arylalkyl group, and a hydrocarbon group having 1 to 12 carbon atoms. Examples thereof include polymerizable vinyl monomers.

The polyvinyl alcohol resin used in the present invention is usually obtained by polymerizing vinyl acetate to obtain polyvinyl acetate and then saponifying. The saponification degree may be complete saponification or partial saponification.
The polyvinyl pyrrolidone resin used in the present invention is usually obtained by polymerizing vinyl pyrrolidone.

  The polyether resin used in the present invention is usually obtained by ring-opening polymerization of cyclic alkylene oxide or cyclic alkylene imine. The bonding method with the modified propylene polymer is not limited. For example, a method of ring-opening polymerization of cyclic alkylene oxide in the modified propylene polymer, a polyether polyol or polyether amine obtained by ring-opening polymerization, etc. And a method of reacting a hydrophilic polymer having a reactive group with a modified propylene polymer. Polyetheramine is a compound having a primary amino group as a reactive group at one or both ends of a resin having a polyether skeleton. Polyether polyol is a compound having hydroxyl groups as reactive groups at both ends of a resin having a polyether skeleton. Preferred examples of the polyalkylene oxide and polyalkyleneimine exhibiting hydrophilicity include polyethylene oxide, propylene-based polymer oxide, and polyethyleneimine.

  The hydrophilic polymer (B) used in the present invention preferably has one or more reactive groups capable of reacting with the modified propylene polymer. Examples of the reactive group include a carboxylic acid group, a dicarboxylic acid anhydride group, and a dicarboxylic acid anhydride monoester group, a hydroxyl group, an amino group, an epoxy group, and an isocyanate group, and preferably an amino group. Since the amino group is highly reactive with various reactive groups such as a carboxylic acid group, a carboxylic anhydride group, a glycidyl group, and an isocyanate group, the modified propylene polymer and the hydrophilic polymer are easily bonded. The amino group may be primary, secondary, or tertiary, but more preferably is a primary amino group.

  The number of reactive groups may be one or more, but more preferably it has only one reactive group. When there are two or more reactive groups, there is a possibility that a three-dimensional network structure will be formed upon bonding with the modified propylene polymer, resulting in gelation. However, even if it has a plurality of reactive groups, it is sufficient if only one reactive group is more reactive than the others. For example, a hydrophilic polymer having a plurality of hydroxyl groups and one amino group having a higher reactivity is a preferred example. Here, the reactivity is the reactivity with the reactive group of the modified propylene polymer.

  The hydrophilic polymer (B) in the present invention preferably has a weight average molecular weight Mw measured by GPC and converted by a polystyrene calibration curve of 200 to 100,000. A more preferable value of the lower limit value is 300, and more preferably 500. A more preferable value of the upper limit is 50,000, and more preferably 10,000. As the Mw is higher than the lower limit value, the hydrophilicity of the graft polymer is increased and the dispersed particle size tends to be smaller and stably dispersed. As the Mw is lower than the upper limit value, the viscosity is low and the resin dispersion tends to be easily prepared. The GPC measurement is performed by a conventionally known method using a commercially available apparatus using THF or the like as a solvent.

  The amount of the hydrophilic polymer (B) to be bound to the propylene polymer is preferably in the range of 0.01 to 5 mmol, that is, 0.01 to 5 mmol / g, per 1 g of the modified propylene polymer. A more preferable lower limit is 0.05 mmol / g, and further preferably 0.1 mmol / g. A more preferred upper limit is 1 mmol / g, and even more preferably 0.5 mmol / g. The higher the lower limit value, the greater the hydrophilicity of the graft polymer and the smaller the dispersed particle size tends to be stably dispersed, and the lower the upper limit value, the greater the adhesion to the crystalline propylene polymer that is the substrate. It is in.

  The modified propylene polymer and the hydrophilic polymer (B) are a graft copolymer in which the hydrophilic polymer (B) is graft-bonded to the modified propylene polymer, at one end or both ends of the modified propylene polymer. There may be a block copolymer of a modified propylene polymer and a hydrophilic polymer (B) containing a state in which the hydrophilic polymer (B) is bonded, but a graft copolymer is preferred. There is an advantage that the content of the hydrophilic polymer (B) can be easily controlled and the content of the hydrophilic polymer (B) can be easily increased as compared with the block copolymer.

The hydrophilic polymer (B) can be bonded to the modified propylene polymer by various reaction forms. Although the form is not specifically limited, For example, it is a reaction using a radical graft reaction or a reactive group.
According to the radical graft reaction, a bond by a carbon-carbon covalent bond is formed.
The reaction using a reactive group has a reactive group in both the modified propylene polymer and the hydrophilic polymer (B) and reacts them to bond them, and a covalent bond or an ionic bond is present. It is formed. Examples of this reaction include (ring-opening) esterification reaction of (anhydrous) carboxylic acid group and hydroxyl group, ring-opening reaction of carboxylic acid group and epoxy group, ring-opening of primary or secondary amino group and epoxy group Reaction, (anhydrous) carboxylic acid group and primary or secondary amino group (ring-opening) amidation reaction or imidation reaction, carboxylic acid group and tertiary amino group quaternary ammonium reaction, carboxylic acid group and isocyanate Examples include amidation reactions of groups, urea reactions of primary or secondary amino groups and isocyanate groups, urethane reactions of hydroxy groups and isocyanate groups, and the like. Among them, the ring-opening amidation reaction or imidation reaction between a carboxylic anhydride group and a primary or secondary amino group is preferable in terms of high reactivity. Furthermore, amidation is more preferable than NH group than imidation. Since the hydrophilic group of COOH group remains in the group, it is preferable from the viewpoint of easy emulsification. The reaction rate of each reaction may be arbitrarily selected from 1 to 100%, preferably 50 to 100%, more preferably 70 to 100%. When the carboxylic acid group is a dibasic acid or an anhydride thereof, one equivalent or two equivalents may be reacted with respect to one equivalent of the dibasic acid or anhydride.

[4] Polymer (C) in which modified propylene polymer is further bonded to hydrophilic polymer (B)
As a method for producing a polymer (C) by bonding a modified propylene polymer and a hydrophilic polymer (B), a hydrophilic monomer is usually polymerized in the presence of the modified propylene polymer, and the modified propylene polymer is obtained. A method (R1) for forming a hydrophilic polymer (B) bonded to a polymer, or a method (R2) for bonding a prepolymerized hydrophilic polymer (B) to a modified propylene polymer. What is necessary is just to select suitably according to the kind and combination of a polymer and a hydrophilic polymer, the characteristic of the target polymer, etc.

[4-1] Method for producing polymer (C) (R1)
In this method, a polymer (C) obtained by polymerizing a hydrophilic monomer in the presence of a modified propylene polymer to bond the modified propylene polymer with the hydrophilic polymer (B) is obtained. As a method for polymerizing the hydrophilic monomer, for example, addition polymerization, condensation polymerization, ring-opening polymerization and the like can be used. At this time, a hydrophobic monomer may be copolymerized as long as a hydrophilic polymer can be formed after polymerization.

  Specifically, for example, there is a method in which a hydrophilic radical polymerizable unsaturated compound is polymerized in the presence of a radical polymerization initiator to form a hydrophilic polymer (B) and bonded to a modified propylene polymer. The hydrophilic radically polymerizable unsaturated compound is not particularly limited. For example, (meth) acrylic acid, hydroxyethyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, dimethylaminoethyl (meth) acrylate, ( Examples include methacrylic acid dimethylaminoethyl quaternized compounds, vinyl pyrrolidone and the like. Examples of the copolymerizable hydrophobic monomer include (meth) acrylic acid esters such as methyl (meth) acrylate and butyl (meth) acrylate, and vinyl acetate.

  Alternatively, a radical polymerizable unsaturated compound is polymerized in the presence of a radical polymerization initiator to form a polymer and bonded to a modified propylene polymer, and then the polymer is modified to be hydrophilic and a hydrophilic polymer (B ). Examples thereof include a method of polymerizing t-butyl (meth) acrylate and then hydrolyzing it under acidic conditions to modify it into poly (meth) acrylic acid, and a method of polymerizing vinyl acetate and then saponifying and modifying it into polyvinyl alcohol. Examples of the copolymerizable hydrophobic monomer include (meth) acrylic acid esters such as methyl (meth) acrylate and butyl (meth) acrylate, and vinyl acetate.

Alternatively, a hydrophilic radical polymerizable unsaturated compound, a hydrophilic ring-opening polymerization monomer, or the like is polymerized using the reactive group of the modified propylene polymer as a starting terminal, and the modified propylene polymer becomes a hydrophilic polymer (B). There is a method of obtaining a polymer (C) formed by bonding with . As the hydrophilic radical-polymerizable unsaturated compound, those described above can be used similarly. Examples of the hydrophilic ring-opening polymerization monomer include ethylene oxide, propylene oxide, and ethyleneimine. Examples of the copolymerizable hydrophobic monomer include trimethylene oxide, tetrahydrofuran, β-propiolactone, γ-butyrolactone, and ε-caprolactone. Any of these may be used alone or in combination of two or more.

The reaction method is not particularly limited as long as a polymer satisfying the requirements of the present invention can be produced, and any method may be used. For example, a solution modification method and a melt modification method are mentioned. As a solvent in the case of manufacturing in a solution, the solvent quoted in the manufacturing method of [1] propylene-type polymer can be used similarly.
The reaction temperature is usually in the range of 0 to 200 ° C, preferably in the range of 30 to 150 ° C. The reaction time is usually about 1 to 20 hours in the solution modification method, and the residence time is about 10 seconds to 10 minutes in the melt modification method.

[4-2] Method for producing polymer (C) (R2)
In this method, the previously polymerized hydrophilic polymer (B) is bonded to the modified propylene polymer. In this case, as the hydrophilic polymer (B), those mentioned in [3] can be used.
Specifically, for example, when a hydrophilic monomer is first polymerized into a hydrophilic polymer, an unsaturated double bond is left in the molecule, and then a modified propylene-based polymer using a radical polymerizable initiator is used. There is a method of graft polymerization.
There is also a method in which a hydrophilic polymer having a reactive group at the terminal is first polymerized and then bonded to a modified propylene polymer. The hydrophilic polymer having a reactive group at the terminal can be obtained by polymerizing a hydrophilic monomer using a compound having a reactive group as an initiator or a chain transfer agent. Alternatively, it can also be obtained by ring-opening polymerization of a hydrophilic ring-opening polymerization monomer such as an epoxy compound. As the hydrophilic monomer that can be used at this time, various hydrophilic monomers listed in [4-1] can be used in the same manner. Any of these may be used alone or in combination of two or more.

The reaction method is not particularly limited as long as a polymer satisfying the requirements of the present invention can be produced, and any method may be used. For example, a solution modification method and a melt modification method are mentioned. As a solvent in the case of manufacturing in a solution, the solvent quoted in the manufacturing method of [1] propylene-type polymer can be used similarly.
The reaction temperature is usually in the range of 0 to 200 ° C, preferably in the range of 30 to 150 ° C. The reaction time is usually about 1 to 20 hours in the solution modification method, and the residence time is about 10 seconds to 10 minutes in the melt modification method.

[5] Aqueous resin dispersion and production method thereof The production method of the aqueous resin dispersion of the present invention is not particularly limited. For example, the modified propylene polymer (a propylene polymer modified with the polymer (C)) is used. In some cases, a solvent other than water is added and dissolved, and then water is added to form a dispersion. After the molten polymer is melted at a temperature higher than the melting point of the modified propylene polymer, water is added to the dispersion. And the like.

  Among these, a method of adding a solvent other than water to the modified propylene-based polymer and adding water after heating and dissolving as necessary is more preferable because an aqueous dispersion having a finer particle size can be easily produced. The temperature at the time of dissolution in a solvent or at the time of addition of water is usually 30 to 150 ° C. Moreover, when dissolving once in solvents other than water, after adding water, you may distill a solvent off. The ratio of the solvent other than water in the resin dispersion is usually 40% or less. It is preferably 20% or less, more preferably 10% or less, and particularly preferably 1% or less.

  Examples of the solvent other than water used in the present method include aromatic hydrocarbons such as toluene and xylene, aliphatic hydrocarbons such as hexane, octane and decane, and alicyclic aliphatic systems such as cyclohexane and methylcyclohexane. Halogenated hydrocarbons such as hydrocarbons, methylene chloride, carbon tetrachloride, chlorobenzene, esters such as methyl acetate, ethyl acetate, propyl acetate, butyl acetate, acetone, methyl ethyl ketone, methyl propyl ketone, methyl isobutyl ketone, cyclohexanone, etc. Ketones, methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-butanol, isobutanol, t-butanol, cyclohexanol, ethylene glycol, propylene glycol, butanediol and other alcohols, dipropyl alcohol Organic solvents having two or more functional groups such as 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, 2-methoxypropanol, 2-ethoxypropanol, diacetone alcohol, etc. , Polar solvents such as dimethylformamide and dimethyl sulfoxide.

  Among them, a solvent that dissolves 1% by mass or more in water is preferable, and more preferably 5% by mass or more. For example, methyl ethyl ketone, methyl propyl ketone, cyclohexanone, n-propanol, isopropanol, n-butanol, 2-butanol. , Isobutanol, t-butanol, cyclohexanol, tetrahydrofuran, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, 2-methoxypropanol, 2-ethoxypropanol and diacetone alcohol are preferred.

An apparatus for producing an aqueous resin dispersion by adding water after the solvent is dissolved and in a molten state is not particularly limited, and for example, a reaction kettle with a stirring device, a uniaxial or biaxial kneader, or the like can be used. The stirring speed at that time varies slightly depending on the selection of the apparatus, but is usually in the range of 10 to 1000 rpm.
In particular, since the polymer (C) to which the hydrophilic polymer is bonded is very excellent in water dispersibility, there is an advantage that the dispersed particle diameter is fine and the resin is stably dispersed. Therefore, when this is used, a coated product having an excellent appearance can be obtained.

  As for the dispersed particle diameter of the polymer (resin) in the aqueous resin dispersion, a cumulative 50% particle diameter (referred to as 50% particle diameter or 50% average particle diameter) is calculated from the smaller particle diameter in terms of volume. In general, it is 3 μm or less, preferably 1 μm or less, with a 50% particle size. According to the present invention, the 50% particle size can be 0.5 μm or less, more preferably 0.3 μm or less, and still more preferably 0.2 μm or less. Similarly, when the 90% particle diameter is determined, the 90% particle diameter can be more preferably 1 μm or less, and particularly preferably 0.5 μm or less. By reducing the dispersed particle size, the dispersion stability is improved, aggregation is unlikely to occur, and the dispersion can be more stably dispersed. Further, a reduction in the ratio of the 90% particle diameter to the 50% particle diameter means that the particle size distribution becomes narrow, and as a result, the dispersion stability is improved.

In the present invention, the term “dispersion” is a concept including a state in which dispersed particles are extremely small and dispersed in a single molecule, and a state that can be said to be substantially dissolved. Accordingly, there is no particular limitation on the lower limit value of the dispersed particle size.
The solid content of the aqueous resin dispersion of the present invention is preferably 5% by weight or more, more preferably 10% by weight or more, and further preferably 20% by weight or more. Further, it is preferably 60% by weight or less, and more preferably 50% by weight or less. The smaller the amount of solid content, the lower the viscosity, the easier it can be applied to various application methods and the higher the stability as a dispersion. However, for example, when used as a primer or an adhesive, it is preferable that the solid content is large so that a large amount of energy and time are not required for drying water after coating.

<Basic substance>
A basic substance can be added to the aqueous resin dispersion of the present invention as necessary. In particular, when the aqueous dispersion is performed without bonding a hydrophilic polymer, it is preferable to increase the hydrophilicity by neutralizing the organic acid group of the modified propylene polymer with a basic substance. Examples of basic substances include inorganic bases such as sodium hydroxide and potassium hydroxide, ammonia, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, ethanolamine, propanolamine, diethanolamine, N-methyldiethanolamine, Organic bases such as dimethylamine, diethylamine, triethylamine, tripropylamine, N, N-dimethylethanolamine, 2-dimethylamino-2-methyl-1-propanol, 2-amino-2-methyl-1-propanol, morpholine Can be mentioned. Of these, alkanolamines having a hydroxyl group and an amino group such as dimethylethanolamine and 2-methyl-2-amino-propanol are preferable. Moreover, in order to improve the water resistance of the film after coating and drying, the basic substance is preferably volatilized under drying conditions, and the boiling point is preferably 200 ° C. or lower, more preferably 150 ° C. or lower. The lower limit of the boiling point is not particularly defined, but in order to prevent volatilization during storage, the boiling point is preferably 0 ° C or higher, more preferably 50 ° C or higher.

<Surfactant>
As described above, according to the present invention, an aqueous resin dispersion can be obtained without using a surfactant, and therefore, one of the advantages is that bleed-out caused by a conventional surfactant can be suppressed. . However, for the purpose of improving the wettability to the base material to be applied, for example, a surfactant may be included as necessary depending on the application. As the surfactant, for example, a cationic surfactant, an anionic surfactant, a nonionic surfactant, an amphoteric surfactant, and the like can be used. As the surfactant, those having an alkyl group, alkenyl group, alkylaryl group or alkenylaryl group having 4 or more carbon atoms as a hydrophobic group are usually used. Preferably it is C8 or more, More preferably, it is C12 or more. However, it usually has 30 or less carbon atoms.

  Examples of the nonionic surfactant include polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene sorbitan monolaurate, and the like. Examples of the anionic surfactant include sodium dodecylbenzenesulfonate, sodium sulfosuccinate, sodium lauryl sulfate, and sodium polyoxyethylene lauryl sulfate. Examples of the cationic surfactant include stearyl trimethyl ammonium chloride, cetyl trimethyl ammonium bromide and the like. Examples of amphoteric surfactants include lauryldimethylaminoacetic acid betaine.

Moreover, what is called a reactive surfactant etc. in which said surfactant has a radically polymerizable functional group can also be used. When a reactive surfactant is used, the water resistance of a film formed using this resin dispersion can be improved. Typical commercially available reactive surfactants include Eleminol JS-2 (manufactured by Sanyo Chemical Industries) and Latemuru S-180 (manufactured by Kao).
A smaller amount of the surfactant is preferable, and the surfactant content of the aqueous resin dispersion is preferably 10 parts by mass or less with respect to 100 parts by mass of the polymer. More preferably, it is 5 mass parts or less, More preferably, it is 2 mass parts or less. Most preferably, it is substantially free of surfactant. “Substantially no surfactant” means less than 1 part by mass with respect to 100 parts by mass of the polymer.

By reducing the amount of the surfactant, there is an advantage that a bleed out that has been a problem in the past can be suppressed and a coated product having an excellent appearance can be obtained, and the present resin dispersion can be used as a coating on the outermost surface of the coating. Moreover, since the water resistance of the coating tends to decrease when a surfactant is contained, it is desirable that the amount of the surfactant is small in this respect as well.
However, since the nonionic surfactant is less likely to lower the water resistance compared to other surfactants, the nonionic surfactant may be included in a slightly larger amount. For example, when the surfactant other than the nonionic surfactant should be 5 parts by weight or less with respect to 100 parts by weight of the polymer, the nonionic surfactant may be 10 parts by weight or less.
Another advantage of the present invention is that the amount of surfactant can be reduced without using chlorinated polyolefin, and the environmental load can be reduced.

[5-1] Combined use of other resins The aqueous resin dispersion of the present invention may be added to the modified propylene-based polymer as necessary in order to impart functions other than adhesion to a polyolefin substrate. It is also possible to mix the aqueous resin. Specific examples include aqueous resins such as acrylic resins, polyester resins, polyurethane resins, and epoxy resins. The form of the aqueous resin dispersion containing these resins and the modified propylene polymer is not particularly limited. For example, there are a method of emulsifying and mixing these resins and modified propylene polymers, or a method of emulsifying these resins and modified propylene polymers after mixing.

  The resin content is preferably in the range of 90:10 to 10:90 in mass ratio of the modified propylene polymer and the other resin. That is, the total amount of the modified propylene polymer and other resins is 100 parts by mass, and the amount of the modified propylene polymer is preferably 10 parts by mass or more, and preferably 90 parts by mass or less. When the amount of the modified propylene polymer is less than 10 parts by mass, the adhesion to the polyolefin substrate tends to be insufficient. More preferably, it is 15 mass parts or more, More preferably, it is 20 mass parts or more. When the amount of the modified propylene polymer is larger than 90 parts by mass, the improvement of the strength, water resistance, weather resistance, abrasion resistance, solvent resistance and the like of the coating film due to the addition of the resin becomes insufficient. More preferably, it is 85 mass parts or less, More preferably, it is 80 mass parts or less.

(D-1) Acrylic resin The acrylic resin of the present invention is not particularly limited as long as it is a (meth) acrylic polymer, but a homopolymer or copolymer of acrylic acid and / or an ester thereof, methacrylic acid and / or Or the homopolymer or copolymer of the ester. In addition, (meth) acryl refers to acryl and / or methacryl. Specific examples of the (meth) acrylate ester include (meth) acrylate ester monomers having an alkyl group having 1 to 12 carbon atoms such as methyl (meth) acrylate, ethyl (meth) acrylate, (meth ) N-propyl acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, (meth) acrylic Hexyl acid, cyclohexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, or the like, or (Meth) acrylic acid ester having an aryl group or an aralkyl group having 6 to 12 carbon atoms, such as Meth) phenyl acrylate include benzyl (meth) acrylate and the like.

  Alternatively, (meth) acrylic acid esters having a C 1-20 alkyl group containing a hetero atom, such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, (meth) acrylic acid- 2-aminoethyl, (meth) acrylic acid glycidyl, (meth) acrylic acid-2-hydroxyethyl, (meth) acrylic acid hydroxybutyl, (meth) acrylic acid-2-methoxyethyl, (meth) acrylic acid-3- Methoxypropyl, (meth) acrylic acid and polyethylene oxide adducts, etc., (meth) acrylic acid esters having a C 1-20 alkyl group containing a fluorine atom, such as trifluoromethyl methyl (meth) acrylate , (Meth) acrylic acid 2-trifluoromethylethyl, (meth) acrylic 2 Pa - fluoroethyl ethyl and the like, (meth) acrylamide monomers such as (meth) acrylamide, and the like (meth) acrylic dimethyl amide, respectively.

(D-2) Polyurethane resin The urethane resin of the present invention is not particularly limited. For example, (i) a component containing two or more active hydrogens in average in one molecule and (ii) a polyvalent isocyanate A urethane polymer obtained by reacting a component, or an isocyanate group-containing prepolymer obtained by reacting the component (i) and the component (ii) under an isocyanate group-excess condition and a chain extender such as a diol. The urethane polymer obtained by making it react is mentioned. These urethane polymers may contain an acid component (acid residue).

The chain extension method of the isocyanate group-containing prepolymer may be a known method. For example, water, a water-soluble polyamine, glycols or the like is used as the chain extender, and the isocyanate group-containing prepolymer and the chain extender component are used. May be reacted in the presence of a catalyst as necessary.
The component containing an average of 2 or more active hydrogens in one molecule of the component (i) is not particularly limited, but preferably has a hydroxylic active hydrogen. Specific examples of such compounds include the following.

  (1) Diol compound: ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 2,3-butylene glycol, 1,4-butylene glycol, 1,5- Pentanediol, neopentyl glycol, 1,6-hexane glycol, 2,5-hexanediol, dipropylene glycol, 2,2,4-trimethyl-1,3-pentanediol, tricyclodecane dimethanol, 1,4- Cyclohexanedimethanol and the like.

  (2) Polyether diols: alkylene oxide adducts of the above diol compounds, ring-opening (co) polymers of alkylene oxides and cyclic ethers (tetrahydrofuran, etc.) such as polyethylene glycol, polypropylene glycol, ethylene glycol-propylene glycol (block) Or random) copolymer, glycol, polytetramethylene glycol, polyhexamethylene glycol, polyoctamethylene glycol, and the like.

  (3) Polyester diol: Dicarboxylic acid (anhydride) such as adipic acid, succinic acid, sebacic acid, glutaric acid, maleic acid, fumaric acid, phthalic acid, and ethylene glycol, propylene glycol as mentioned in (1) above , 1,4-butanediol, 1,6-hexanediol, 1,8-octamethylenediol, neopentylglycol and other diol compounds obtained by polycondensation under hydroxyl group-excess conditions. Specifically, ethylene glycol-adipic acid condensate, butanediol-adipine condensate, hexamethylene glycol-adipic acid condensate, ethylene glycol-propylene glycol-adipic acid condensate, or lactone is opened using glycol as an initiator. Examples thereof include polymerized polylactone diol.

(4) Polyether ester diol: (anhydrous) dicarboxylic acid as exemplified in the above (3), an ether group-containing diol (polyether diol or diethylene glycol of (2) above) or a mixture of this with another glycol And a product obtained by reacting an alkylene oxide in addition to, for example, a polytetramethylene glycol-adipic acid condensate.
(5) Polycarbonate diol: General formula HO—R— (O—C (O) —O—R) _x —OH (wherein R is a saturated fatty acid diol residue having 1 to 12 carbon atoms, x is a molecular weight) The compound etc. which show the number of repeating units, and are the integers of 5-50 normally.). These include a transesterification method in which a saturated aliphatic diol and a substituted carbonate (diethyl carbonate, diphenyl carbonate, etc.) are reacted under the condition that the hydroxyl group is excessive, the saturated aliphatic diol and phosgene are reacted, or as necessary. Then, it can be obtained by a method of further reacting with a saturated aliphatic diol.

The compounds as exemplified in the above (1) to (5) can be used alone or in combination of two or more.
As the polyisocyanate component (ii) to be reacted with the component (i), an aliphatic, alicyclic or aromatic compound containing an average of two or more isocyanate groups in one molecule can be used.

  The aliphatic diisocyanate compound is preferably an aliphatic diisocyanate having 1 to 12 carbon atoms, and examples thereof include hexamethylene diisocyanate and 2,2,4-trimethylhexane diisocyanate. The alicyclic diisocyanate compound is preferably an alicyclic diisocyanate having 4 to 18 carbon atoms, and examples thereof include 1,4-cyclohexane diisocyanate and methylcyclohexylene diisocyanate. Examples of the aromatic isocyanate include tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, and xylylene diisocyanate.

  In addition, those containing acid residues in the urethane-based polymer can be dispersed in water without using a surfactant or in a small amount, so that the water resistance of the coating film is improved. There is expected. The content of the acid residue is preferably in the range of 25 to 150 (mgKOH / g), preferably 30 to 100 (mgKOH / g) as the acid value of the urethane polymer. If the acid value is less than 25, the water dispersibility tends to be insufficient, and it is often necessary to use a surfactant. On the other hand, if the acid value is more than 150, the water resistance of the coating film tends to be poor.

  As a method for introducing an acid group into a urethane polymer, a conventionally used method can be used without any particular limitation. For example, dimethylolalkanoic acid is one of the glycol components described in (2) to (4) above. A method of introducing an acid group by introducing a carboxyl group into a polyether diol, a polyester diol, a polyether ester diol or the like in advance by substituting a part or all of them is preferable. Examples of the dimethylolalkanoic acid used here include dimethylolacetic acid, dimethylolpropionic acid, and dimethylolbutyric acid.

(D-3) Polyester resin The polyester resin of the present invention is not particularly limited, and examples thereof include dicarboxylic acids such as adipic acid, succinic acid, sebacic acid, glutaric acid, maleic acid, fumaric acid, and phthalic acid, and the like. / Or anhydrides thereof and diol compounds such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octamethylenediol, neopentylglycol, or ether group-containing diols (polyethylene glycol) And polypropylene glycol, polytetramethylene glycol, and the like).

Specific examples include an ethylene glycol-adipic acid condensate, a butanediol-adipine condensate, a hexamethylene glycol-succinic acid condensate, an ethylene glycol-propylene glycol-phthalic acid condensate, and a polyethylene glycol-adipic acid condensate. .
An aqueous dispersion of the polyester resin can be obtained by emulsifying these in the presence or absence of a surfactant. Although the manufacturing method is not specifically limited, it can manufacture according to the manufacturing method of the aqueous dispersion of the above-mentioned acrylic resin. Examples of commercially available products include Byronal MD-1200 and MD-1245 manufactured by Toyobo.

(D-4) Epoxy resin The epoxy resin of the present invention is not particularly limited as long as it is a polymer having one or more epoxy groups in one molecule. For example, by reacting polyhydric phenol with epichlorohydrin in the presence of alkali. Examples thereof include polyhydric glycidyl ethers of phenol that can be produced, and epoxy group-containing polymers obtained by reacting such polyhydric glycidyl ethers of phenol with the above polyhydric phenols.

  Examples of the polyhydric phenol that can be used here include bis (4-hydroxyphenyl) -2,2-propane, 4,4′-dihydroxybenzophenone, bis (4-hydroxyphenyl) -1,1-ethane, Bis (4-hydroxyphenyl) -1,1-isobutane, bis (4-hydroxy-t-butyl-phenyl) -2,2-propane, bis (2-hydroxynaphthyl) methane, 1,5-dihydroxynaphthalene, etc. Can be mentioned.

Instead of these polyhydric phenols, hydrogenated compounds obtained by adding hydrogen to part or all of the double bonds of the phenyl nucleus can also be used.
Further, as the epoxy resin, polyglycidyl ether of phenol novolac resin and polyglycidyl ether of polyhydric alcohol can also be used. Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,4-propylene glycol, 1,5-pentanediol, 1,2,6-hexanetriol, and glycerol. , Bis (4-hydroxycyclohexyl) -2,2-propane, sorbitol and the like.

An aqueous dispersion of an epoxy resin is obtained by emulsifying these in the presence or absence of a surfactant. Although the manufacturing method is not specifically limited, it can manufacture according to the manufacturing method of the aqueous dispersion of the above-mentioned acrylic resin.
As a typical product available as a commercial product, a de novolak type epoxy resin obtained by adding epichlorohydrin to a phenol novolac resin and forcibly emulsified with a surfactant (emulsifier) is a denar EM150 manufactured by Nagase Chemtech Co., Ltd. , Epiretz 6006W70, 5003W55 manufactured by Japan Epoxy Resin Co., Ltd., WEX-5100 manufactured by Toto Kasei Co., Ltd., and the like.

  Although it does not specifically limit as a polymerization method for manufacturing these aqueous resins, For example, methods, such as solution polymerization, bulk polymerization, emulsion polymerization, or suspension polymerization, can be used. In order to emulsify the resin obtained by solution polymerization and bulk polymerization into an aqueous emulsion to form an aqueous dispersion, emulsification and dispersion are performed by mechanical force such as colloid mill in the presence or absence of the solution, and then necessary. Accordingly, the residual solvent may be distilled off under reduced pressure or atmospheric pressure. If emulsion polymerization or suspension polymerization is used, the polymer can be obtained directly as an aqueous emulsion.

[5-2] Addition of pigment A pigment can be added to the aqueous resin dispersion of the present invention. An aqueous resin dispersion containing a pigment is suitable as a paint. The pigment that can be used is not particularly limited. For example, inorganic pigments such as titanium oxide, carbon black, iron oxide, chromium oxide, bitumen, bengara, yellow lead, yellow iron oxide, azo pigments, anthracene pigments, and perinone pigments. , Perylene pigments, quinacridone pigments, isoindolinone pigments, indigo pigments, organic pigments such as phthalocyanine pigments, etc .; extenders such as talc, calcium carbonate, clay, kaolin, silica, precipitated barium sulfate ; Conductive pigments such as whiskers coated with conductive carbon and antimony-doped tin oxide; non-colored or colored metallic luster such as aluminum, copper, zinc, nickel, tin, aluminum oxide, or other metals or alloys 1 type, or 2 or more types may be used in combination.

  The amount of the pigment added to the aqueous resin dispersion is preferably 10 parts by weight or more with respect to 100 parts by weight of the propylene polymer in a weight ratio. More preferably, it is 50 parts by weight or more. However, it is preferably 400 parts by weight or less, and more preferably 200 parts by weight or less. As the added amount is larger than the lower limit, the color developability and concealment tend to be higher, and as the amount is lower than the upper limit, the adhesion tends to be higher.

  At this time, a pigment dispersant may be used. For example, an aqueous acrylic resin such as Jonkrill Resin manufactured by Johnson Polymer Co., Ltd .; an acidic block copolymer such as BYK-190 manufactured by BYK Chemie Co., Ltd .; a styrene-maleic acid copolymer; manufactured by Air Products (Air Products Co., Ltd.) Examples thereof include acetylenic diol derivatives such as Surfynol T324; water-soluble carboxymethyl acetate butyrate such as CMCAB-641-0.5 manufactured by Eastman Chemical Company. By using these pigment dispersants, a stable pigment paste can be prepared.

<Other additives>
The aqueous resin dispersion of the present invention can contain various additives as required within a range that does not significantly impair the effects of the present invention. For example, various stabilizers such as ultraviolet absorbers, antioxidants, weathering stabilizers, heat resistance inhibitors; colorants such as titanium oxide and organic pigments; conductivity imparting agents such as pigments, carbon black and ferrite, dyes, pigment dispersions Various additives such as additives, leveling agents, antifoaming agents, thickeners, preservatives, fungicides, rust inhibitors and wetting agents may be used in combination.

Examples of the antifoaming agent include Surfynol 104PA and Surfynol 440 manufactured by Air Products.
To further improve the performance of various coatings such as water resistance and solvent resistance. The crosslinking agent can be added in an amount of 0.01 to 100 parts by weight with respect to 100 parts by weight of the resin in the dispersion. As the crosslinking agent, there can be used a crosslinking agent having self-crosslinking property, a compound having a plurality of functional groups that react with a carboxyl group in the molecule, a metal complex having a polyvalent coordination site, etc. Among them, an isocyanate compound, Melamine compounds, urea compounds, epoxy compounds, carbodiimide compounds, oxazoline group-containing compounds, zirconium salt compounds, silane coupling agents and the like are preferable. Moreover, you may use combining these crosslinking agents.

  When the aqueous resin dispersion of the present invention is used for applications such as primers, paints and inks, a hydrophilic organic solvent other than water may be blended for the purpose of increasing the drying speed or obtaining a good surface finish. it can. Examples of the hydrophilic organic solvent include alcohols such as methanol, ethanol and isopropyl alcohol, ketones such as acetone, glycols such as ethylene glycol and propylene glycol, and ethers thereof. In addition, organic or inorganic compounds other than those described above can be added to the resin dispersion as long as the stability of the resin dispersion is not impaired.

  The resin dispersion of the present invention can be used for primers, paints, inks, adhesives, and the like, and can be particularly useful as paints and primers. As applications, it can be used for automobile paints and primers for automobile interior and exterior, paints for home appliances such as mobile phones and personal computers, paints for building materials, and the like.

[6] Application of aqueous resin dispersion The aqueous resin dispersion of the present invention exhibits excellent adhesion to a base material such as polyolefin by low-temperature baking, and the resulting film has solvent resistance (oil resistance, GH resistance). ), Excellent in chemical resistance, water resistance and moisture resistance. The method for forming the resin layer on the substrate is not particularly limited, and a known method can be used. For example, a method of applying an aqueous resin dispersion by spray, a method of applying by a roller, or applying by a brush And a coating method using a gravure coater, bar coater, spin coater, or the like. In general, spray coating is suitable for injection moldings such as automobiles and home appliance parts, and gravure coaters, bar coaters and the like are suitable for substrates such as films and sheets.

  After applying the aqueous resin dispersion, the coating film is cured according to a normal method of heating with nichrome wire, infrared rays, high frequency, etc., and a laminate having a desired coating film on the surface can be obtained. The curing conditions for the coating film are appropriately selected depending on the material and shape of the substrate, the composition of the aqueous resin dispersion used, and the like. Although there is no restriction | limiting in particular in curing temperature, Considering practicality, it is 40 degreeC or more normally, Preferably it is 50 degreeC, More preferably, it is 60 degreeC or more. However, it is usually 150 ° C. or lower, preferably 100 ° C. or lower, more preferably 80 ° C. or lower. The aqueous resin dispersion of the present invention has a high adhesive force even when applied and dried at a relatively low temperature. In particular, about 60 to 80 ° C. is suitable.

  The thickness of the propylene-based polymer layer to be laminated can be appropriately selected depending on the material and shape of the base material, the composition of the aqueous resin dispersion to be used, etc., but is usually 0.1 μm or more, preferably 1 μm or more, more preferably Is 3 μm or more. However, it is usually 500 μm or less, preferably 300 μm or less, more preferably 100 μm or less.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not restrict | limited to a following example, unless the summary is exceeded.
[Physical property measurement method and evaluation method]
(1) Physical property measurement method (1-1) Stereoregularity The stereoregularity [mmmm] of the propylene polymer is measured by ¹³ C-NMR spectrum measurement method using an NMR apparatus (manufactured by JEOL Ltd., 400 MHz). did. 350-500 mg of sample was completely dissolved in about 10 ml of a sample tube for NMR using about 2.2 ml of orthodichlorobenzene. Next, about 0.2 ml of deuterated benzene was added as a lock solvent, and the mixture was homogenized. Then, measurement was performed at 130 ° C. by a complete proton decoupling method. The measurement conditions were a flip angle of 90 ° and a pulse interval of 5T ₁ or more (T ₁ is the longest value of the spin lattice relaxation time of the methyl group). In the propylene-based polymer, since the spin lattice relaxation time of the methylene group and methine group is shorter than that of the methyl group, the recovery of the magnetization of all the carbons is 99% or more under this measurement condition. Measurement was carried out by integrating over 20 hours.

(1-2) Molecular weight First, 20 mg of a sample was collected in a 30 ml vial, and 20 g of orthodichlorobenzene containing 0.04% by weight of BHT was added as a stabilizer. After dissolving the sample using an oil bath heated to 135 ° C., it was filtered hot with a PTFE (polytetrafluoroethylene) filter having a pore diameter of 3 μm to prepare a sample solution having a polymer concentration of 0.1% by weight. Next, GPC measurement was performed by using TSKgel GM H-HT (30 cm × 4) as a column and Waters GPC150CV equipped with an RI detector. As measurement conditions, a sample solution injection amount: 500 μl, a column temperature: 135 ° C., a solvent: orthodichlorobenzene, and a flow rate: 1.0 ml / min were employed.

  When calculating the molecular weight, use a commercially available monodisperse polystyrene as a standard sample, create a calibration curve for the retention time and molecular weight from the polystyrene standard sample and the viscosity formula of the propylene polymer, and calculate the molecular weight of the propylene polymer. Was calculated. [Η] = K · Mα is used as the viscosity formula, K = 1.38E-4 and α = 0.70 for polystyrene, and K = 1.03E- for propylene-based copolymers. 4, α = 0.78 was used.

(1-3) Melting | fusing point Melting | fusing point of a propylene polymer was calculated | required with the following method using the Perkin-Elmer thermal analysis system (DSC-7). A sample (about 5 to 10 mg) was melted at 160 ° C. for 3 minutes, cooled to −20 ° C. at a rate of 10 ° C./minute, held at −20 ° C. for 2 minutes, and then increased to 160 ° C. at 10 ° C./minute. The melting curve was obtained by heating, and the peak top temperature of the main endothermic peak in the final temperature rising stage was determined as the melting point.

(1-4) Graft rate 200 mg of the polymer and 4800 mg of chloroform are put into a 10 ml sample bottle and heated at 50 ° C. for 30 minutes to be completely dissolved. Chloroform was placed in a liquid cell having a material NaCl and an optical path length of 0.5 mm as a background. Next, the dissolved polymer solution was put into a liquid cell, and an infrared absorption spectrum was measured using FT-IR460plus manufactured by JASCO Corporation at a total number of 32 times. For example, the graft ratio of maleic anhydride was calculated using a calibration curve prepared by measuring a solution of maleic anhydride in chloroform. Then, from the area of the absorption peak of the carbonyl group (maximum peak in the vicinity of 1780 cm ⁻¹ , 1750 to 1813 cm ⁻¹ ), the acid component content in the polymer is calculated based on a separately prepared calibration curve, and this is calculated as the graft ratio ( % By weight).

(1-5) Dispersion particle diameter It measured using Nikkiso Co., Ltd. Nanotrac EX-150. The density of the dispersion was 0.9 g / cm ³ , the shape was spherical, the dispersion medium was water and the measurement time was 120 seconds, and the 50% particle diameter (volume average particle diameter) and 90% particle diameter were determined.

(2) Evaluation of Aqueous Resin Dispersion (2-1) Storage Stability Evaluation Observation of appearance after storage of sample in 50 g glass sample bottle and storage at 40 ° C. for 1 month, and change in average particle diameter (aggregation) (Increase in average particle diameter).

○: No change in appearance, change in average particle size is less than 20% Δ: No major change in appearance, change in average particle size is 20% or more and less than 50% ×: Large change in appearance (3) Evaluation of aqueous resin dispersion as a primer for paints

(3-1) Initial Adhesion Test A substrate made by injection molding a 70 mm × 150 mm × 3 mm propylene-based polymer (Exxon Co., Ltd., 8224) for automobile exterior is created, and the substrate surface is wiped with isopropyl alcohol. did. The sample was spray coated so that the dry weight after coating was about 5 g / m ^2, and the test piece after coating was dried at 60 ° C. for 5 minutes in a safe ben dryer. Next, an acrylic polyol urethane paint (Letane PG80III: manufactured by Kansai Paint Co., Ltd.), in which a specified amount of curing agent was blended on this coating film and the viscosity was adjusted with a special thinner, was applied in an amount of 30 to 40 g / m ^2. And then baked in a safe ben dryer at 60 ° C. for 20 minutes.

Subsequently, the test piece was cured at 40 ° C. for 24 hours, and then allowed to stand at 23 ° C. for 24 hours.
In accordance with the cross cut test method described in JIS K5400, a 25 square (5 × 5) cross cut is applied to the test piece, and cellophane tape (Nichiban Co., Ltd.) is applied, and then 90 ° It was made to peel in the direction. Repeat three times. Initial adhesion was evaluated by the number of grids that were not peeled out of 25 grids.

(3-2) Peel peel strength test In the initial adhesion test, a two-component urethane paint for peel peel measurement was used instead of the acrylic polyol urethane paint (Letane PG80III), and the coating amount was 200 to 300 g / m ^2. A test piece was prepared in the same manner as in the initial adhesion test except that it was spray-coated on a substrate and baked in a safe bend dryer at 60 ° C. for 20 minutes.
Subsequently, the test piece was cured at 40 ° C. for 24 hours, and then allowed to stand at 23 ° C. for 24 hours.
The test piece was cut into a width of 10 mm, a 180 ° peel test was conducted at a peel rate of 50 mm / min, and the peel peel strength was measured.

(3-3) Gasohol resistance test The edge of the coated plate produced in the same manner as the initial adhesion test was cut off with a cutter, and the test piece with the painted cross-section exposed was placed between regular gasoline and ethanol kept at 20 ° C. It was immersed in a mixed liquid (volume ratio: regular gasoline / ethanol = 9/1), and the time until peeling occurred in the coating film was measured and evaluated according to the following criteria.

○: No peeling of the coating film is observed for 1 minute or more. Δ: The coating film peels in 30 seconds or more and less than 1 minute. ×: The coating film peels within 30 seconds.

(3-4) Bleed-out of surfactant As in the initial adhesion test, the coated plate produced by applying and drying the sample to the substrate was left at 40 ° C. for 3 days. The bleed-out of the surfactant on the coating film surface was evaluated.

○: No bleed-out of surfactant △: Slightly bleed-out surfactant ×: Many bleed-out surfactants, sticky when touched with a finger

(4) Evaluation of water-based resin dispersion as heat seal adhesive (4-1) Peel peel strength test A film having a thickness of 100 μm was prepared by molding homopolypropylene (manufactured by Nippon Polypro Co., Ltd., MA3U). A film obtained by adding 50 parts by weight of isopropyl alcohol to 100 parts by weight of the sample and diluting the film was coated with a bar coater (No. 16), and dried at 80 ° C. for 2 minutes. The coating amount of the propylene polymer was about 3 g / m ² . Overlay the same polypropylene film with no sample on the coating, change the heat seal setting temperature to 60 ° C, 80 ° C, 100 ° C, heat at a pressure of 2 kg / cm ² and a pressurization time of 3 seconds Sealing was performed.

  The obtained laminated film was cut into a width of 15 mm, a 180 ° (T-shaped) peel test was performed at a peel rate of 300 mm / min, and the peel peel strength was measured. The higher the peel peel strength, the higher the heat seal adhesion.

(4-2) Blocking property An uncoated polypropylene film is superposed on a film coated with a sample, and a load is applied at room temperature at a load of 0.1 kg / cm ² for 1 hour. The film was taken out and a peel test was performed by hand. The degree of blocking was evaluated according to the following criteria.

○: There is no resistance at the time of peeling, or it is peeled off lightly ×: There is considerable resistance at the time of peeling, and it is difficult to peel off or does not peel off

[Production Example 1-1: Production of propylene-based polymer]
In a 1,000 ml round bottom flask, 110 ml of demineralized water, 22.2 g of magnesium sulfate heptahydrate and 18.2 g of sulfuric acid were collected and dissolved with stirring. In this solution, 16.7 g of commercially available granulated montmorillonite was dispersed, heated to 100 ° C., and stirred for 2 hours. Then, it cooled to room temperature and filtered the obtained slurry, and collect | recovered the wet cake. The recovered cake was slurried again with 500 ml of demineralized water in a 1,000 ml round bottom flask and filtered. This operation was repeated twice. The finally obtained cake was dried at 110 ° C. overnight under a nitrogen atmosphere to obtain 13.3 g of chemically treated montmorillonite.

To 4.4 g of the obtained chemically treated montmorillonite, 20 ml of a toluene solution of triethylaluminum (0.4 mmol / ml) was added and stirred at room temperature for 1 hour. To this suspension was added 80 ml of toluene, and after stirring, the supernatant was removed. After repeating this operation twice, toluene was added to obtain a clay slurry (slurry concentration = 99 mg clay / ml).
In a separate flask, 0.2 mmol of triisobutylaluminum was collected, and 19 ml of the clay slurry obtained here and dichloro [dimethylsilylene (cyclopentadienyl) (2,4-dimethyl-4H-5,6,7,8 -Tetrahydro-1-azulenyl) Hafnium 131 mg (57 μmol) in toluene was added and stirred at room temperature for 10 minutes to obtain a catalyst slurry. (For details of the catalyst production method, see JP-A 2004-002310).

  Next, 11 L of toluene, 3.5 mmol of triisobutylaluminum and 2.64 L of liquid propylene were introduced into an induction stirring autoclave having an internal volume of 24 liters. The whole amount of the catalyst slurry was introduced at room temperature, the temperature was raised to 60 ° C., and the total pressure during polymerization was kept constant at 0.65 MPa, and stirring was continued for 2 hours at the same temperature. After completion of the stirring, unreacted propylene was purged to terminate the polymerization. The autoclave was opened and the whole toluene solution of the polymer was recovered, and the solvent and clay residue were removed. As a result, 11 kg of a 7.9 wt% toluene solution of a propylene polymer was obtained. The resulting propylene polymer had a weight average molecular weight Mw of 250,000 and a stereoregularity [mmmm] of 50%. The physical properties of the resulting propylene polymer are shown in Table 1.

[Production Examples 1-2 to 1-6: Production of propylene-based polymer]
A propylene-based polymer was obtained in the same manner as in Production Example 1-1 except that the total pressure and temperature during polymerization were changed to those described in Table-1. The physical properties of the resulting propylene polymer are shown in Table 1.
In addition, physical properties of commercially available propylene polymers are shown as Reference Examples 1 to 4. Reference Example 1 (Lycocene PP1502 manufactured by Clariant) is a propylene polymer produced using a metallocene catalyst. Reference Example 2 (Ubekku UT2115 manufactured by Ube Industries) is an amorphous propylene polymer. Reference Example 3 (Wintech WFX6 manufactured by Nippon Polypro Co., Ltd.) is a propylene-based polymer produced using a metallocene catalyst. Reference Example 4 (Yumex 1010 manufactured by Sanyo Chemical Industries, Ltd.) is a maleic anhydride modified product (acid value 52 mgKOH / g, 5% by weight as maleic anhydride) of a low molecular weight propylene polymer by thermal degradation.

[Production Example 2-1: Production of maleic anhydride-modified propylene polymer]
In a glass flask equipped with a reflux condenser, thermometer, and stirrer, 40 g of the propylene polymer obtained in Production Example 1-1, 160 g of the propylene polymer obtained in Production Example 1-5, and 300 g of toluene. The inside of the container was replaced with nitrogen gas, and the temperature was raised to 110 ° C. After heating, 10 g of maleic anhydride was added, 5 g of t-butyl peroxyisopropyl monocarbonate (manufactured by NOF Corporation, Perbutyl I) was added, and the reaction was continued for 7 hours at the same temperature. After completion of the reaction, the system was cooled to around room temperature, acetone was added, and the precipitated polymer was filtered off. Further, precipitation and filtration were repeated with acetone, and the finally obtained polymer was washed with acetone. The polymer obtained after washing was dried under reduced pressure to obtain a maleic anhydride-modified polymer in the form of a white powder. As a result of measuring the infrared absorption spectrum of this modified polymer, the content (graft ratio) of maleic anhydride groups was 1.1% by weight (0.11 mmol / g as maleic anhydride groups). The weight average molecular weight is 56,000, and the physical properties of the resulting maleic anhydride-modified propylene polymer are shown in Table 2.

[Production Examples 2-2 to 2-15: Production of maleic anhydride-modified propylene polymer]
In the same manner as in Production Example 2-1, except that the types and amounts of the propylene-based polymers as the components (A1) and (A2), the amounts of maleic anhydride, perbutyl I, and toluene were the conditions described in Table-2. Then, a maleic anhydride-modified propylene polymer was obtained. Table 2 shows the physical properties of the resulting maleic anhydride-modified propylene polymer.

[Example 1: Production of polyalkylene glycol-modified propylene polymer aqueous resin dispersion]
In a glass flask equipped with a reflux condenser, a thermometer and a stirrer, 100 g of maleic anhydride-modified propylene polymer obtained in Production Example 2-1 (content of maleic anhydride group: 12 mmol) and 250 g of toluene were added. The temperature was raised to 0 ° C. and completely dissolved. Next, a solution obtained by dissolving 15.0 g (15.0 mmol, corresponding to 15 parts by weight with respect to 100 parts by weight of a propylene polymer) of poly (oxyethylene / oxypropylene) block copolymer (molecular weight 1000) in 22.5 g of toluene. And reacted at 110 ° C. for 3 hours.

After cooling, toluene was distilled off under reduced pressure to obtain 113 g of a yellow polymer. As a result of infrared absorption spectrum analysis of the obtained product, the peak corresponding to maleic anhydride in the vicinity of 1784 cm ⁻¹ disappears, and the maleic anhydride-modified propylene polymer and the polyether are bonded. confirmed. A graft copolymer is formed by grafting a polyether to a maleic anhydride-modified propylene polymer.

  To 40 g of the resulting modified polymer, 160 g of tetrahydrofuran (THF) was added and completely dissolved at 65 ° C. 200 g of pure water was added dropwise at the same temperature over 1 hour to obtain a translucent pale yellow solution. This was cooled to 50 ° C., the pressure was gradually reduced from 0.03 MPa to 0.0045 MPa, and THF and water were distilled off under reduced pressure until the resin solids concentration was 21% by weight. A resin dispersion was obtained. As a result of measuring the dispersed particle size, the 50% particle size was 0.04 μm, and the 90% particle size was 0.09 μm. The physical properties of the obtained aqueous resin dispersion are shown in Table-3. The particle size was small and the storage stability was good.

  The poly (oxyethylene / oxypropylene) block copolymer used in this example has an insoluble content of 1% by weight or less when dissolved in water at 25 ° C. at a concentration of 10% by weight, and is hydrophilic. It is a polymer.

[Examples 2 to 5, Comparative Examples 1 to 7: Production of polyalkylene glycol-modified propylene polymer aqueous resin dispersion]
The same as in Example 1 except that the type and amount of the maleic anhydride-modified propylene polymer and the amount of the poly (oxyethylene / oxypropylene) block copolymer as the component (B) were the conditions shown in Table-3. Thus, an aqueous resin dispersion was obtained. The physical properties of the obtained aqueous resin dispersion are shown in Table-3.

Each of the aqueous resin dispersions of Examples 2 to 5 had a small particle size and good storage stability.
The aqueous resin dispersion of Comparative Example 6 had a remarkably large 50% particle size because the resin was agglomerated, and the 90% particle size was not measurable. In the aqueous resin dispersion of Comparative Example 7, a large amount of aggregate was observed, and the particle size was not measurable.

[Comparative Example 8: Production of maleic acid-modified propylene polymer aqueous resin dispersion with surfactant]
In a glass flask equipped with a reflux condenser, a thermometer, and a stirrer, 20 g of the maleic anhydride-modified propylene polymer obtained in Production Example 2-13 and 80 g of toluene were placed and heated to 110 ° C. to be completely dissolved. . After cooling to 50 ° C., 5 g of polyoxyethylene cetyl ether (nonionic surfactant, Emulgen 220 manufactured by Kao Corporation, HLB = 14.2) and polyoxyethylene lauryl ether (nonionic surfactant, Kao ( Emulgen 147, HLB = 16.3) 5 g was added and dissolved, and then cooled to 35 ° C.

  After 100 g of water was added and sufficiently stirred, emulsification was carried out at 21000 rpm for 3 minutes using an internal shear type emulsifier CLEARMIX CLM-0.8S (manufactured by M Technique). Subsequently, an aqueous solution obtained by diluting 2-amino-2-methyl-1-propanol with water to 10% by weight was added to the system, and the pH was adjusted to 8. The crude emulsion was gradually reduced in pressure from a temperature of 50 ° C. and a reduced pressure of 0.02 MPa to 0.0045 MPa to distill off toluene and water to obtain a milky white resin dispersion having a concentration of 25% by weight.

  As a result of measuring the dispersed particle size, the 50% particle size was 0.25 μm, and the 90% particle size was 3.1 μm. The results are shown in Table-3. Both the 50% particle size and the 90% particle size were significantly larger than those of the Examples, and the storage stability was clearly inferior.

[Examples 6 and 7, Comparative Example 9: Production of polyalkylene glycol-modified propylene polymer aqueous resin dispersion]
The same as in Example 1 except that the type and amount of the maleic anhydride-modified propylene polymer and the amount of the poly (oxyethylene / oxypropylene) block copolymer as the component (B) were the conditions shown in Table-3. Thus, an aqueous resin dispersion was obtained. The physical properties of the obtained aqueous resin dispersion are shown in Table-3.

In Examples 6 and 7, two types of propylene-based polymers modified with maleic anhydride were separately used to form an aqueous resin dispersion, but the particle size was small, the storage stability was good, and good physical properties were obtained. It has been.
The aqueous resin dispersion of Comparative Example 9 had a large amount of aggregates, and the particle size was not measurable.

[Evaluation of aqueous resin dispersion as primer for paint]
The aqueous resin dispersions of Examples 1 to 4 and Comparative Examples 1 to 5 and 8 were evaluated as paint primers. The results are shown in Table-4. The aqueous resin dispersions of Examples 1 to 4 were excellent in adhesion and solvent resistance during low-temperature baking, and no bleed-out was observed. In Comparative Examples 1 to 5 and 8, adhesion and solvent resistance were poor, and in Comparative Example 8 using a surfactant, bleeding out was observed.

[Evaluation of aqueous resin dispersion as heat seal adhesive]
The aqueous resin dispersions of Examples 2 to 7 and Comparative Examples 1 to 3 and 8 were evaluated as heat seal adhesives. The results are shown in Table-5. The aqueous resin dispersions of Examples 2 to 7 exhibited excellent adhesiveness even at a very low heat seal temperature at a heating temperature of less than 100 ° C., and no blocking occurred. In Comparative Examples 1-3 and 8, the low-temperature heat sealability was insufficient or blocking occurred.

Claims (7)

The following propylene polymers (A1) and (A2) are aqueous resin dispersions in which a modified propylene polymer obtained by modification with an unsaturated organic acid derivative is dispersed in water, wherein the unsaturated organic acid derivative is The propylene polymer (A1) and / or (A2), which is at least one selected from the group consisting of unsaturated carboxylic acids and unsaturated dicarboxylic acid anhydrides and modified with unsaturated organic acid derivatives, is a polyalkylene An aqueous resin dispersion characterized by being bonded to a polyether resin having a structure.
(A1): Propylene polymer having no melting point or a melting point of less than 75 ° C. and a weight average molecular weight of 10,000 to 100,000 (A2): melting point of 70 ° C. or more and less than 120 ° C., weight Propylene polymer having an average molecular weight of 100,000 to 500,000 and at least 1.5 times the weight average molecular weight of (A1)   The aqueous resin dispersion according to claim 1, comprising the polymers (A1) and (A2) at (A1) :( A2) = 10: 90 to 90:10 (weight ratio).   The aqueous polymer dispersion according to claim 1 or 2, wherein the polymers (A1) and (A2) are mixed and then modified with an unsaturated organic acid derivative.   The aqueous resin dispersion according to claim 1 or 2, wherein the polymers (A1) and (A2) are each modified with an unsaturated organic acid derivative and then mixed.   The aqueous resin dispersion according to any one of claims 1 to 4, wherein the polyether resin is graft-bonded to the polymer (A1) and / or (A2). A method for producing an aqueous resin dispersion according to claim 1, 2, 3 or 5,
A mixture of the propylene-based polymers (A1) and (A2), modified with an unsaturated organic acid derivative , bonded with a polyether resin, and then dispersed in water. Production method. A method for producing an aqueous resin dispersion according to claim 1, 2, 4 or 5,
An aqueous resin dispersion characterized in that the propylene polymers (A1) and (A2) are each modified with an unsaturated organic acid derivative and then mixed, to which a polyether resin is bonded, and then dispersed in water. Production method.