JP2005162976A - Resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a resin composition having an excellent adhesion and containing water, which has an excellent storage stability and can give a good working environment and undergo a uniform curing reaction even at an ordinary temperature when vaporizing the water content, and to prepare a coating film which is excellent in adhesion and heat resistance and has hydrophilicity. <P>SOLUTION: This resin composition contains a silane coupling agent which has a 1-5C alkoxy group and amino group, a polyester which has as the constitutional component a polyethylene glycol and an acid value of 3-100 KOHmg/g, and water. The coating film is formed by curing the above resin composition. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a room temperature curable resin composition containing water. Furthermore, this invention relates to the hydrophilic coating film formed with the said resin composition.

Does not contain organic solvents, does not generate irritants such as formaldehyde during curing, and has a good working environment, as a vehicle for paints, inks, coating materials, adhesives, etc., or a processing agent for fibers, films, and paper products As a resin composition useful for such as, a self-dispersing water-based polyester (see Patent Document 1) and a thermosetting resin composition containing a curing agent such as an organic peroxide (see Patent Document 2) have been proposed. ing. However, the curing of these resin compositions requires heating, requires heat source equipment, and cannot be cured at any place. Therefore, when a peroxide having a low half-life temperature is used to lower the curing temperature, the storage stability of the resin composition is deteriorated.
JP-A-5-295100 JP 2000-264938

  The present invention provides a water-containing resin composition that has excellent storage stability, has a good working environment, and can easily cause a uniform curing reaction even at room temperature by evaporating water, and has excellent adhesion. The purpose is to provide. Furthermore, an object of this invention is to provide the coating film which is excellent in adhesiveness and heat resistance, and has hydrophilic property.

That is, the gist of the present invention is as follows.
[1] A resin composition comprising a silane coupling agent having an alkoxy group having 1 to 5 carbon atoms and an amino group, a polyester having an acid value of 3 to 100 KOHmg / g containing polyethylene glycol as a constituent, and water. And [2] a coating film obtained by curing the resin composition according to [1].

  The resin composition containing water of the present invention has excellent storage stability, good working environment, and easily causes a uniform curing reaction even at room temperature by evaporating water, and has excellent adhesion and heat resistance. In order to produce a coating film having hydrophilicity, by using such a resin composition, the surface of the coating is desired to be hydrophilic, such as paints, inks, coating materials, adhesives, etc., or processing agents for fibers, films and paper products. Can be suitably used.

  As described above, the resin composition of the present invention includes a silane coupling agent having an alkoxy group having 1 to 5 carbon atoms and an amino group, a polyester having polyethylene glycol as a constituent component and an acid value of 3 to 100 KOHmg / g, In addition, by using such a resin composition, a uniform curing reaction easily occurs even at room temperature, and excellent adhesion to a uniform coating film or various members. The effect of bringing about it, and also the hydrophilicity of the coating film surface are expressed.

Among them, in the resin composition of the present invention, by using the specific silane coupling agent and the specific polyester in combination, not only the polyester and the silane coupling agent react at the time of curing, but also the silane coupling agent. Since it itself undergoes hydrolysis and self-condensation reactions, or reacts with functional groups on the substrate surface such as fibers and aggregates, it improves the adhesion between the resin component and / or various substrates, or increases the coating strength. And improve the properties of the composite material.
In addition, about the alkoxysilanes which do not have an amino group conventionally used as a coupling agent, as shown in the comparative example mentioned later, it is inferior to adhesiveness and normal temperature sclerosis | hardenability.

  The silane coupling agent used in the present invention has an alkoxy group having 1 to 5 carbon atoms, and from the viewpoint of excellent adhesion and room temperature curability, the following formula (1):

(In the formula, R ¹ is an alkylene group having 2 to 5 carbon atoms (preferably 3 carbon atoms), R ² may be the same or different and preferably 1 to 5 carbon atoms (preferably 1 to 2 carbon atoms, particularly 1). Or an alkoxy group having 1 to 5 carbon atoms (preferably 1 to 2 carbon atoms, particularly 1), provided that at least one of R ² is an alkoxy group (preferably a di- or trialkoxy group). is there.)
It is preferable to have a structural unit represented by the following formula (2):

(In the formula, R ¹ and R ² are the same as described above. R ³ represents an alkylene group having 2 to 5 carbon atoms (preferably 2 carbon atoms).)
It is more preferable to have a structural unit represented by the formula (3):

(Wherein R ^{1 to} R ³ are the same as described above. R ⁴ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms (preferably a hydrogen atom) which may have a hydroxyl group).
Is particularly preferred.

  Examples of the silane coupling agent include N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl). -Γ-aminopropylmethyldiethoxysilane, N-β- (aminoethyl) -γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-amino Examples thereof include propyltrimethoxysilane, and those having a di- or trialkoxysilyl group are particularly preferable. These can be easily obtained from Shin-Etsu Chemical Co., Ltd. These silane coupling agents can be used alone or in admixture of two or more.

  The polyester contained in the resin composition of the present invention can be cured by the presence of the silane coupling agent as long as it has an acid value of 3 to 100 KOHmg / g containing polyethylene glycol as a constituent component.

  If the acid value of this polyester is less than 3 KOHmg / g, the reaction point with the silane coupling agent tends to decrease and the heat resistance tends to decrease, and if it exceeds 100 KOHmg / g, the silane coupling agent for reaction If the amount is less than the required amount, the heat resistance tends to decrease, such being undesirable. The acid value of the polyester is preferably 10 to 70 KOHmg / g, more preferably 15 to 50 KOHmg / g, from the viewpoint of excellent adhesion, water emulsification and curability. The acid value is measured according to JIS K 0070.

  The polyester may be modified with an amide bond, a urethane bond, an epoxy bond or the like, but is preferably not modified. Even those obtained by transesterification of a high molecular weight polyester such as polyethylene terephthalate with a carboxylic acid can be used as long as the acid value is within the above range. However, what transesterified the high molecular weight polyester with alcohol is not preferable because the acid value is less than 3 KOHmg / g.

  The softening point of the polyester is 0 to 100 ° C., preferably 20 to 90 ° C., from the viewpoint of bond strength. The number average molecular weight is preferably 1000 to 30,000, more preferably 2000 to 10,000.

  The polyester used in the present invention contains polyethylene glycol as an essential component as a constituent monomer, and the average molecular weight of polyethylene glycol is preferably 800 to 6000, more preferably 1000 to 6000. From the viewpoint of hydrophilicity, the amount of polyethylene glycol is preferably 5 to 35% by weight, more preferably 10 to 35% by weight, of all monomers constituting the polyester.

  The polyester used in the present invention can be produced by polycondensing an acid component and a polyol component listed below as constituent monomers.

  Examples of the acid component include maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, dimer acid, alkenyl (carbon number 4 to 20) succinic acid, and cyclohexanedicarboxylic acid. , Divalent carboxylic acids such as naphthalenedicarboxylic acid, and trivalent carboxylic acids such as 1,2,4-benzenetricarboxylic acid, acid anhydrides thereof, and lower alkyl (carbon number 1 to 4) esters. These can be used alone or in admixture of two or more.

  On the other hand, as the polyol component, in addition to essential polyethylene glycol, preferably ethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol, glycerin, pentaerythritol, trimethylolpropane, sorbitol, 1,6- Aliphatic polyols having 2 to 10 carbon atoms such as hexanediol or aromatic polyols such as bisphenol A and hydrogenated bisphenol A and their alkylene (2 to 3 carbon) oxide adducts (addition moles: 2 to 20 moles) ). In particular, an alkylene oxide adduct of bisphenol A is preferable from the viewpoint of heat resistance, and it is preferably contained in an amount of 50 to 100 mol%, more preferably 80 to 100 mol%, in an alcohol component other than polyethylene glycol.

  Polycondensation of a polyol component and an acid component can be performed by a known method, for example, by reacting a polyol component containing polyethylene glycol and an acid component at a temperature of 180 to 250 ° C. in an inert gas atmosphere. The end point thereof may be determined by tracking the acid value, the softening point, etc., which are molecular weight indicators.

  The molar ratio between the polyol component and the acid component may be appropriately determined depending on the acid value, softening point, number average molecular weight, and the like of the polyester obtained. Component: acid component).

  In this condensation polymerization, additives such as an esterification catalyst such as dibutyltin oxide and a radical polymerization inhibitor such as hydroquinone and t-butylcatechol can be appropriately used.

  The acid value, softening point and number average molecular weight of the resulting polyester can be adjusted, for example, by adjusting the type of raw material, the molar ratio of the acid component / polyol component, the reaction temperature, the reaction time, and the like. it can.

  When the polyester is an unsaturated polyester having a radically polymerizable monomer such as fumaric acid as a constituent component, a radical generator may be added to assist curing. As a method for adding the radical generator, the method described in JP-A No. 2000-264938 may be used, and if it is water-soluble, it can be added to a polyester in an aqueous dispersion as described later. Examples of radical generators include water-soluble curing agents such as hydrogen peroxide, ammonium persulfate, 2,2-azobis (2-amidinopropane) dihydrochloride, benzoyl peroxide, 2,2′-azobis-isobutyronitrile, etc. Oil-soluble curing agents and the like.

  Furthermore, curing accelerators such as aniline derivatives and sodium sulfite may be added.

  In the present invention, the form of the polyester is preferably a water emulsion or an aqueous dispersion previously neutralized with a basic compound from the viewpoint of uniform curability, and the average particle diameter is preferably 0. 0.005 to 10 μm, more preferably 0.01 to 2 μm. In addition, the said acid value is preferable also from a viewpoint of obtaining a water emulsion or a water dispersion. The average particle size is measured with a laser diffraction particle size distribution analyzer, SALD-2000J (trade name, manufactured by Shimadzu Corporation).

  The basic compound is not particularly limited as long as it can ionize the carboxyl group of polyester, but is preferably a hydroxide such as alkali metal or alkaline earth metal, ammonia and organic amines, and ammonia and organic amines. Are preferred because they cure quickly. As the organic amines, triethylamine, N, N-diethylethanolamine, N, N-dimethylethanolamine and triethanolamine are preferable from the viewpoint of the stability of the aqueous dispersion.

  The amount of the basic compound is preferably 0.8 to 1.4 equivalents relative to 1 equivalent of carboxyl groups in the polyester from the viewpoint of producing a stable aqueous emulsion or aqueous dispersion.

  Further, the production method of the water emulsion or dispersion is not particularly limited, but the method of emulsifying the polyester in hot water, the method of adding a basic compound to the emulsion, the polyester and the basic Examples thereof include a method of forcibly emulsifying the compound in water, if necessary, in the presence of a known surfactant by an emulsifier, or a method of phase inversion emulsification. In the phase inversion emulsification, it is preferable to dissolve the polyester in an organic solvent, add a basic compound and water, and, if necessary, a surfactant, and then distill the organic solvent to invert to an aqueous system. The average particle size can be appropriately adjusted by changing the molecular weight, acid value, neutralization degree, phase inversion emulsification conditions, etc. of the polyester.

  The organic solvent is preferably water-soluble and has a lower boiling point than water, such as acetone, isopropyl alcohol, methyl ethyl ketone, and THF. As the usage-amount of an organic solvent, it is preferable that it is 100-600 weight part of organic solvents with respect to 100 weight part of polyester used for a water emulsion or a water dispersion.

  The amount of water at the time of emulsification or phase inversion is preferably 100 to 1000 parts by weight with respect to 100 parts by weight of polyester. In this case, 1-20 parts by weight of a surfactant such as a higher alcohol sulfate, polyoxyethylene alkyl ether sulfate, dialkylsulfosuccinate, β-naphthalenesulfonic acid formalin condensate salt, etc. in 100 parts by weight of polyester. It may be further added to adjust the average particle size of the resin fine particles in the water emulsion or water dispersion.

  The organic solvent is preferably distilled off under reduced pressure at 25 to 70 ° C., and the content of the organic solvent is preferably adjusted to 1% by weight or less, more preferably 0.1% by weight or less. In the case of phase inversion, it is more preferable to adjust using the above basic compound or the like so that the pH of the obtained treatment liquid is 6 to 10.

  Water may be further added to the water emulsion or water dispersion obtained as described above.

  The content of the polyester in the water emulsion or water dispersion is preferably 10 to 60% by weight, more preferably 20 to 50% by weight, and the water content is preferably 40 to 90% by weight, more Preferably it is 50 to 80% by weight.

  In the present invention, the resin composition of the present invention that reacts and cures at room temperature by evaporation of moisture can be obtained by using polyester as a water emulsion or water dispersion and combining it with the silane coupling agent. When the silane coupling agent is mixed with the water emulsion or water dispersion, in addition to direct mixing, the silane coupling agent may be mixed with the water emulsion or water dispersion after adding the silane coupling agent to various substrates. Good.

  Among them, the weight ratio of the water emulsion of the polyester or the water dispersion / the silane coupling agent in the resin composition of the present invention is 70/30 to 99.9 / 0.1 in terms of strength and curing time. 80/20 to 99/1 are more preferable.

  10-60 weight% is preferable and, as for content of polyester in the resin composition of this invention, 20-50 weight% is more preferable. The content of the silane coupling agent is preferably 0.1 to 30% by weight, and more preferably 1 to 20% by weight. The water content is preferably 39.9 to 89.9% by weight, more preferably 49 to 79% by weight.

  In the resin composition of the present invention, a known catalyst such as dibutyltin dilaurate or stannous octoate may be used in order to promote hydrolysis and self-condensation reaction of the silane coupling agent.

  In addition to the above components, the resin composition of the present invention includes various known additives such as ultraviolet absorbers such as benzotriazole and benzophenone, antifungal agents such as chloromethylphenol, chelating agents such as EDTA, Known fillers such as sulfites, calcium carbonate, and talc, known plasticizers such as diallyl phthalate, pigments, dyes, oxygen absorbers, and the like may be blended within a range that does not impair the desired effects of the present invention. The polyester may be added internally.

  In the resin composition of the present invention, all of the above components or appropriately selected components can be mixed in advance to prepare a preparation, or they can be mixed immediately before use to prepare a preparation. .

  The resin composition of the present invention is excellent in safety and can generate a uniform curing reaction by evaporation of water even at room temperature, and has excellent adhesion to various substrates. It can be suitably used as a vehicle for materials, adhesives and the like, or as a processing agent for fibers, films and paper products.

  Among them, a coating film obtained by curing the resin composition of the present invention by a known method, for example, by evaporating moisture at room temperature, is excellent in adhesion, heat resistance and hydrophilicity, and is preferable. The curing method is not particularly limited as long as it can evaporate water at room temperature.

Resin production example 1
Preparation of polyester water emulsion 3500 g of bisphenol A propylene oxide adduct (average number of moles added: 2.2 mol), 1150 g of fumaric acid, 1170 g of polyethylene glycol (average molecular weight 1000), 0.3 g of hydroquinone and 8.4 g of dibutyltin oxide The reaction was performed at 160 ° C. for 4 hours under a nitrogen stream. Then, after heating up to 210 degreeC, it was made to react at a normal pressure for 4 hours. The obtained polyester was a solid having an acid value of 19.0 KOH mg / g, a hydroxyl value of 50.4 KOH mg / g, a softening point of 48 ° C., and a number average molecular weight of 1820. Next, this polyester heated to 100 ° C. is added to water previously heated to 70 ° C. so as to have a solid content of 30%, stirred at 70 ° C. for 1 hour, and cooled to obtain a polyester water emulsion. Got. This is designated as polyester (A). The softening point was measured by ASTM E26-51T ring and ball softening point measurement method. The acid value and hydroxyl value were measured by the method of JIS K0070. The molecular weight was measured by GPC at 40 ° C., flowing chloroform as an eluent at a flow rate of 1 ml / min, and injecting 100 μl of a chloroform solution having a sample concentration of 0.5% by weight. Standard sample: monodisperse polyethylene. Analysis column: GMHLX + G3000HXL (manufactured by Tosoh Corporation).

Resin production example 2
Preparation of polyester water emulsion 3500 g of bisphenol A propylene oxide adduct (average number of moles added: 2.2 mol), 1700 g of terephthalic acid, 1290 g of polyethylene glycol (average molecular weight 1500) and 8.5 g of dibutyltin oxide in a nitrogen stream The reaction was carried out at 230 ° C. for 5 hours. The obtained polyester was a solid having an acid value of 23.0 KOH mg / g, a hydroxyl value of 38.5 KOH mg / g, a softening point (ring-and-ball type) of 54 ° C., and a number average molecular weight of 1850. Next, this polyester heated to 100 ° C. is added to water previously heated to 70 ° C. so as to have a solid content of 30%, stirred at 70 ° C. for 1 hour, and cooled to obtain a polyester water emulsion. Got. This is designated as polyester (B).

Resin production example 3
3500 g of bisphenol A propylene oxide adduct (average number of moles added: 2.2 mol), 1160 g of fumaric acid, 0.3 g of hydroquinone and 8.4 g of dibutyltin oxide were reacted at 160 ° C. for 4 hours in a nitrogen stream. Then, after heating up to 200 degreeC, it was made to react at normal pressure for 1 hour under the reduced pressure of 9.33 kPa. The obtained polyester was a solid having an acid value (AV) of 23.0 KOHmg / g, a hydroxyl value (OHV) of 33.7 KOHmg / g, a softening point (ring-and-ball type) of 90 ° C., and a number average molecular weight of 3300. This polyester did not dissolve in water and exhibited hydrophobicity.
300 g of this polyester and 45 g of diallyl phthalate were dissolved in 540 g of methyl ethyl ketone. Next, 12 g of N, N-dimethylethanolamine was added to neutralize, and 680 g of ion-exchanged water was added with stirring. Then, methyl ethyl ketone was distilled off at 40 ° C. under reduced pressure to adjust the water content. A dispersed water-based polyester resin (average particle size: 0.46 μm, solid content: 35% by weight) was obtained. This is designated as polyester (C).

Examples 1 and 2 and Comparative Examples 1 to 3
The polyesters (A) to (C) and the silane coupling agent were mixed in the amounts shown in Table 1 to obtain a resin composition, and the film formation time, adhesion, heat resistance and hydrophilicity were evaluated according to the following methods. .

The resin composition was coated on a polyethylene terephthalate film to a thickness of 0.01 mm using a bar coater at room temperature of 24 ° C. The time from the application to the film formation of the resin composition was confirmed by touching with a finger and measured as the film formation time.
In addition, adhesion is evaluated by peeling the film with a metal spatula, and “◎” indicates that the film cannot be peeled off even if force is applied, and “○” indicates that the film is peeled off when force is applied. The thing to be made was made into "x".
The heat resistance was evaluated by peeling a cured product immediately after leaving the polyethylene terephthalate film having a film formed in an oven at 80 ° C. for 100 hours with a spatula. "
The hydrophilicity was evaluated by placing a water drop on the cured coating film and measuring the contact angle with a digital microscope VH-6200 (trade name, manufactured by KEYENCE) after 5 seconds. ° or less was considered good.
The results of Examples 1 and 2 and Comparative Examples 1 to 3 are shown in Table 1.

  From the results of Table 1, the resin compositions of the present invention obtained in Examples 1 and 2 can be cured in a short time at room temperature compared to the resin compositions obtained in Comparative Examples 1 to 3, and the adhesion, It can be seen that both the heat resistance and the hydrophilicity after curing are good. In addition, none of the resin compositions of the present invention obtained in Examples 1 and 2 generated an irritating odor such as an aldehyde odor.

  The resin composition of the present invention can be suitably used as a vehicle for paints, inks, coating materials, adhesives and the like whose surface is desired to be hydrophilic, or as a processing agent for fibers, films and paper products.

Claims (4)

  A resin composition comprising a silane coupling agent having an alkoxy group having 1 to 5 carbon atoms and an amino group, a polyester having polyethylene glycol as a constituent component and an acid value of 3 to 100 KOHmg / g, and water. The silane coupling agent is represented by the following formula (1):

(In the formula, R ¹ represents an alkylene group having 2 to 5 carbon atoms, and R ² represents an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms, which may be the same or different. (At least one of ² is an alkoxy group)
The resin composition of Claim 1 which has a structural unit represented by these.   The resin composition according to claim 1 or 2, wherein a weight ratio of the polyester / silane coupling agent is 70/30 to 99.9 / 0.1.   The coating film formed by hardening the resin composition in any one of Claims 1-3.