JPH09324162A - Acrylic emulsion composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an acrylic emulsion composition, comprising an acrylic emulsion, a specific tackifier emulsion and a specified surfactant, having excellent coating stability even by adding the tackifier for improving the tack properties thereto and useful for a coating material, an adhesive, a tacky agent, etc. SOLUTION: This acrylic emulsion composition comprises (A) an acrylic emulsion, (B) a tackifier emulsion prepared by emulsifying and dispersing (B1 ) a tackifier with (B2 ) an anionic surfactant (e.g. the one obtained by using the component B2 in an amount of 0.1-10 pts.wt. based on 100 pts.wt. solid material in the emulsion) and (C) a polyoxyethylene-based nonionic surfactant having 10-20 hydrophile-lipophile balance(HLB). The composition contains the component B in an amount of preferably 5-100 pts.wt., based on 100 pts.wt. component A and expressed in terms of the amount of the component B1 and the component C in an amount of preferably 1-15 pts.wt. based on 100 pts.wt. component B.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an acrylic emulsion composition.

[0002]

2. Description of the Related Art In recent years, acrylic adhesives have been widely used in place of natural rubber and synthetic rubber adhesives because of their excellent physical property balance and durability. Among them,
Solvent-free acrylic pressure-sensitive adhesives, especially acrylic emulsion pressure-sensitive adhesives, have been widely used in order to prevent pollution problems and environmental problems.

On the other hand, acrylic adhesives are
Addition of terpene-based, rosin-based tackifying resin,
It has been known for a long time that the adhesive property, especially the adhesiveness to an olefin-based adherend is improved. Also in acrylic emulsion pressure-sensitive adhesives, attempts have been made to improve the physical properties of the pressure-sensitive adhesive by adding the above-mentioned tackifying resin.

For example, Japanese Patent Application Laid-Open No. 63-256672 proposes a method of mixing with an acrylic emulsion, but has a problem that mechanical stability (coating stability) becomes extremely poor. It was In addition, JP-A-58-185
Japanese Patent No. 668 discloses a method in which a tackifying resin is dissolved in a monomer containing a crosslinkable monomer to carry out polymerization. However, this method has a problem that the polymerization stability becomes poor when a large amount of tackifying resin is added.

[0005]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems, and an object thereof is to add a tackifier to an acrylic emulsion in order to improve the adhesive property thereof. Mechanical stability (coating stability)
Another object of the present invention is to provide an acrylic emulsion composition having

[0006]

The acrylic emulsion composition of the present invention comprises an acrylic emulsion (A), a tackifier emulsion (B) emulsified and dispersed with an anionic surfactant, and an HLB of 10 to 20. It is characterized by comprising a polyoxyethylene nonionic surfactant (C).

The acrylic emulsion (A) used in the present invention is a (co) polymer containing a (meth) acrylic monomer as a main component, and the (meth) acrylic monomer (a) has a (meth) acrylic group in its molecule. ) Those containing an acryloyl group are preferred. Examples of such (meth) acrylic monomer (a) include methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate,
Examples thereof include isononyl acrylate, lauryl acrylate, acrylic acid, methacrylic acid, acrylamide, methacrylamide, N-isopropylacrylamide, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate and 4-hydroxybutyl acrylate.

The above acrylic emulsion (A)
May be a copolymer of the (meth) acrylic monomer (a) and another monomer (b) copolymerizable with the (meth) acrylic monomer. Examples of such other copolymerizable monomer (b) include maleic acid, itaconic acid, N-vinyl-2-pyrrolidone, N-vinylcaprolactam, styrene, vinyl acetate, and the like. They may be used, or two or more kinds may be used in combination.

The amount of the copolymerizable monomer used is
It is preferably 100 parts by weight or less with respect to 100 parts by weight of the (meth) acrylic monomer (a).

Examples of the surfactant (D) used in the acrylic emulsion (A) include anionic surfactants such as dodecylbenzene sulfonates, alkyl sulfates, polyoxyethylene alkylphenyl ether sulfonates and the like. Agents: Nonionic surfactants such as polyoxyethylene alkylphenyl ether and polyoxyethylene alkyl ether can be used.

Among the above-mentioned surfactants (D), those having a copolymerizable double bond are particularly preferable. Examples of such a surfactant include allyl group-added polyoxyethylene alkylphenyl ether sulfonic acid. Anionic surfactants such as salts and propenyl group-added polyoxyethylene alkylphenyl ether sulfonates; nonionic surfactants such as allyl group-added polyoxyethylene alkylphenyl ether and propenyl group-added polyoxyethylene alkylphenyl ether To be

The amount of the surfactant (D) used is preferably 0.1 to 5 parts by weight, more preferably 0.3 to 3 parts by weight, based on 100 parts by weight of the total amount (a + b) of the monomers.

The (co) polymerization method of the acrylic emulsion (A) is not particularly limited, but a batch (co) polymerization method, a monomer dropping (co) polymerization method, an emulsion monomer dropping (co) polymerization method and the like are adopted. It is possible.
The polymerization initiator used for the (co) polymerization is not particularly limited, and examples thereof include persulfates such as potassium persulfate and ammonium persulfate; water-soluble azo compounds such as ammonium azobiscyanovalerate; hydrogen peroxide and the like. And a reducing agent in combination with a redox polymerization initiator.

The amount of the above polymerization initiator used is preferably 0.01 to 1 part by weight, more preferably 0.02 to 0.5 part by weight, based on 100 parts by weight of the total amount (a + b) of the monomers.

The acrylic emulsion (A) contains
A chain transfer agent such as dodecyl mercaptan may be blended, and the amount thereof is preferably 0.5 part by weight or less based on 100 parts by weight of the total amount (a + b) of the monomers.

The tackifier (hereinafter referred to as TF) emulsion (B) used in the present invention is emulsified and dispersed with an anionic surfactant. The anionic surfactant is not particularly limited as long as it is used for emulsifying and dispersing a hydrophobic substance, and examples thereof include dodecylbenzene sulfonates, alkyl sulfates, and polyoxyethylene alkylphenyl ether sulfone. Examples thereof include acid salts.

The amount of the anionic surfactant used is T
0.1 to 10 parts by weight is preferable with respect to 100 parts by weight of F emulsion (B) (solid content), and more preferably 0.3.
９9 parts by weight.

The method of emulsifying and dispersing the TF emulsion (B) is not particularly limited as long as it is a commonly used method, and for example, a tackifier dissolved in water, a surfactant and a solvent is used. A method of batchwise stirring and emulsifying; a method of dissolving in a solvent and dripping and stirring water and a surfactant into a tackifier and emulsifying by phase inversion;
Examples include a method of preventing boiling of water under high pressure, emulsification using a tackifier that is heated and melted with or without addition of an organic solvent.

The above tackifier emulsion (B)
Examples of commercially available products include "Super Ester E720", "Super Ester E740" manufactured by Arakawa Chemical Co., Ltd.,
"Super Ester E730-55", "Super Ester E625", "Super Ester E650", "Tamanor E100"; Toho Chemical Co., Ltd. "QME60", "Q"
ME100 ”,“ QME120 ”,“ QME125P
"S", "Himax SD60", "Himax SD
90 "," High Mac RE 210 "," High Mac RE
230 ”,“ High Mac ME445 ”,“ High Mac M
E455 ";" Nanolet D20 "manufactured by Yasuhara Chemical Co., Ltd.
0 "," Nanolet G1250 "," Nanolet R10 "
50 ”and the like.

The above tackifier emulsion (B)
The tackifier used for, for example, gum rosin, tall oil rosin, wood rosin, polymerized rosin,
Other than rosin-based resins such as hydrogenated rosin, disproportionated rosin, rosin ester, hydrogenated rosin ester, disproportionated rosin ester, polymerized rosin ester, and rosin-modified phenolic resin,
Terpene resin, hydrogenated terpene resin, phenol resin, terpene phenol resin, hydrogenated terpene phenol resin,
Examples thereof include xylene resin, ketone resin, aliphatic petroleum resin, aromatic petroleum resin, alicyclic petroleum resin, coumarone resin, and styrene resin. These may be used alone or in combination of two or more. You may use together.

The tackifier has a softening point of 0.
℃ or above, more preferably 70 ℃ softening point
That is all. The amount of the tackifier used is preferably 5 to 100 parts by weight, more preferably 10 to 70 parts by weight, based on 100 parts by weight of the acrylic emulsion (A).

The nonionic surfactant (C) used in the present invention is HLB10-20. still,
The above HLB (Hydrophile Lipophile)
e Balance) is an ethylene oxide type and is calculated by the following formula. HLB = E / 5, where E is the weight fraction of polyoxyethylene moieties. The HLB is in the range of 0 to 20, and the smaller the value, the stronger the hydrophobicity, and the larger the value, the stronger the hydrophilicity.

Examples of commercially available nonionic surfactants (C) having the above HLB10 to 20 are those manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. (trade names: Neugen EA80, EA110, EA12).
0, EA140, EA150, EA160, EA17
0, EA190D), manufactured by Kao (trade name: Emulgen 9
06, 909, 910, PI-20T, 911, 91
3, 920, 930, 931, 935, 950, 98
5) polyoxyethylene nonylphenyl ethers such as;
Polyoxyethylene cetyl ether such as manufactured by Kao (trade name: Emulgen 210P, 220); Polyoxyethylene stearyl ether such as manufactured by Kao (trade name: Emulgen 320P); manufactured by Daiichi Kogyo Seiyaku Co., Ltd. (trade name: Neugen EA102) , EA112, EA142, EA152),
Polyoxyethylene octyl phenyl ether such as manufactured by Kao (trade name: Emulgen 810, 840S); polyoxyethylene dodecyl phenyl ether such as manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. (trade name: Neugen EA143); manufactured by Dai-ichi Kogyo Seiyaku ( Product name: Neugen EA126, EA137, EA
157, EA167, EA177, EA141) and other polyoxyethylene alkyl allyl ethers.

Further, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. (trade names: Neugen ET100E, ET120E, ET140E, ET1
50E, ET180E), polyoxyethylene oleyl ether such as those manufactured by Kao (trade names: Emulgen 408, 409P, 420, 430); manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. (trade names: Neugen ET102, ET143, ET160, E).
T170, ET190), manufactured by Kao (trade name: Emulgen 106, 108, 109P, 120, 123P, 14
7, 707, 709) and the like; polyoxyethylene lauryl ether; manufactured by Kao Corporation (trade name: Emulgen 705, 70)
7, 709) and other polyoxyethylene higher alcohol ethers; manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. (trade name: Aqualon RN1)
0, RN20, RN30, RN40) and other propenyl group-added polyoxyethylene nonyl phenyl ethers; Asahi Denka Co., Ltd. (Adecaria Soap NE10, NE20, NE3)
Examples thereof include allyl group-added polyoxyethylene nonylphenyl ethers such as 0).

In addition, manufactured by Kao (trade name: Leo Doll T
Polyoxyethylene sorbitan monolaurate such as W-L120 and TW-L160; polyoxyethylene sorbitan monopalmitate such as manufactured by Kao Corporation (trade name: Leodol TW-P120); manufactured by Kao Corporation (trade name: Leodol TW- S120) and other polyoxyethylene sorbitan monostearate ;; manufactured by Kao (trade name: Rheodor TW
-S320) and other polyoxyethylene sorbitan tristearate; manufactured by Kao Corporation (trade name: Rheodor TW-O1)
20, TW-O106) and other polyoxyethylene sorbitan monooleate; manufactured by Kao (trade name: Rheodor T
Polyoxyethylene sorbitan trioleate such as W-O320); manufactured by Kao Corporation (trade name: Rheodor Super T)
Polyoxyethylene sorbitan monolaurate such as W-L120); manufactured by Kao Corporation (trade name: Rheodor Super T)
W-S120) and other polyoxyethylene sorbitan monostearate; and polyoxyethylene sorbitan monooleate such as those manufactured by Kao (trade name: Rheodor Super TW-O120).

The above nonionic surfactant (C) may be used alone or in combination of two or more kinds. Among the above nonionic surfactants, polyoxyethylene alkylphenyl ether is particularly preferable.

The amount of the nonionic surfactant (C) used is preferably 1 to 15 parts by weight, more preferably 3 parts by weight, relative to 100 parts by weight of the tackifier emulsion (B).
10 to 10 parts by weight.

The acrylic emulsion composition of the present invention is obtained by adding a polyoxyethylene-based nonionic surfactant (C) to a tackifier emulsion (B) emulsified and dispersed with an anionic surfactant, and then adding an acrylic-based emulsion composition. It can be obtained by adding and stirring the emulsion (A), but if necessary, a viscosity modifier, a cross-linking agent, an antioxidant, a light stabilizer, a dye / pigment, a preservative and the like may be added.

Examples of the viscosity modifier include polyacrylic acid salts and water-soluble urethane resins, and the amount thereof is preferably 2 parts by weight or less with respect to 100 parts by weight of the acrylic emulsion (A).

Examples of the cross-linking agent include aziridine-based, block- and self-emulsifying isocyanate-based, carbodiimide-based, and metal-based crosslinking agents, and the amount thereof is 100 parts by weight of the acrylic emulsion (A). On the other hand, it is preferably 30 parts by weight or less. As the addition method, (A) and (B) are used when the acrylic emulsion composition is prepared.
And component (C), or may be added to the acrylic emulsion composition after preparation.

The acrylic emulsion composition obtained in the present invention is preferably used for applications such as paints, adhesives, pressure-sensitive adhesives and sealing materials. Examples of the use of the pressure-sensitive adhesive include pressure-sensitive adhesive tapes, pressure-sensitive adhesive sheets, labels and double-sided pressure-sensitive adhesive tapes. Examples of base materials used for adhesive tapes, adhesive sheets, labels, and double-sided adhesive tapes include resin films such as polyethylene terephthalate and biaxially oriented polypropylene; foams such as polyurethane, polyethylene, rubber; paper, woven cloth, non-woven cloth. And so on.

(Function) In the acrylic emulsion composition of the present invention, HLB is 10 to 2 in the tackifier emulsion (B) emulsified with the anionic surfactant.
By adding the nonionic surfactant (C) of 0, the nonionic surfactant (C) is adsorbed on the surface of the tackifier emulsion (B) particles, and acts as a protective component, and the acrylic emulsion (A) is added. It is considered that the mechanical stability does not decrease even when mixed.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[Preparation of Acrylic Emulsion (A)]
48 parts by weight of n-butyl acrylate, 48 parts by weight of 2-ethylhexyl acrylate, 4 parts by weight of acrylic acid, ammonium propoxy group-added polyoxyethylene nonylphenyl ether sulfate (Aqualon HS-10 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) 0.6 A mixture of 1 part by weight and 0.05 part by weight of dodecyl mercaptan was emulsified with 30 parts by weight of ion-exchanged water to obtain an emulsified monomer. Then, 70 parts by weight of ion-exchanged water and potassium persulfate of 0.
1 part by weight was charged, and polymerization was carried out for 4 hours under a nitrogen atmosphere at 80 ° C. while dropping the emulsified monomer. After the completion of dropping, polymerization was further performed at 80 ° C. for 3 hours to obtain an acrylic emulsion composition (solid content concentration 50% by weight).

Example 1 A non-ionic surfactant (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was stirred into 60 parts by weight of a tackifier emulsion (“Super Ester E740” manufactured by Arakawa Chemical Co., Ltd., component: disproportionated rosin ester). "Neugen EA120", component: polyoxyethylene nonylphenyl ether, HLB = 12) 1.8 parts by weight were added,
Further, 200 parts by weight of the acrylic emulsion (A) was added and stirred to obtain an acrylic emulsion composition.

Example 2 An acrylic emulsion composition was obtained in the same manner as in Example 1 except that the amount of the nonionic surfactant used was 4.8 parts by weight.

Example 3 As a nonionic surfactant, 1.8 weight parts of "Neugen EA170" (component: polyoxyethylene nonylphenyl ether, HLB = 17) manufactured by Daiichi Kogyo Seiyaku Co., Ltd. was used instead of Neugen EA120. An acrylic emulsion composition was obtained in the same manner as in Example 1 except that the parts were used.

Example 4 An acrylic emulsion composition was obtained in the same manner as in Example 3 except that the amount of the nonionic surfactant "Neugen EA170" used was 4.8 parts by weight.

(Example 5) As a nonionic surfactant, instead of Neugen EA120, "Aqualon RN20" manufactured by Daiichi Kogyo Seiyaku Co., Ltd. (component: polyoxyethylene nonylphenyl ether with a propenyl group, HLB = 1)
An acrylic emulsion composition was obtained in the same manner as in Example 1, except that 1.8 parts by weight of 5) was used.

(Example 6) An acrylic emulsion composition was obtained in the same manner as in Example 5, except that the amount of the nonionic surfactant "Aqualon RN20" used was 4.8 parts by weight.

Comparative Example 1 200 parts by weight of the acrylic emulsion (A) was added to 60 parts by weight of a tackifier emulsion ("Super Ester E740" manufactured by Arakawa Chemical Co., Inc., component: disproportionated rosin ester) while stirring. Then, an acrylic emulsion composition was obtained.

The acrylic emulsion compositions obtained in the above Examples and Comparative Examples were evaluated for mechanical stability by the following method, and the results are shown in Table 1. (Evaluation method of mechanical stability) Using a Marlon type mechanical stability tester (Kyowa Interface Science Co., Ltd., emulsion / latex mechanical stability characteristic measurement-recorder "CMS-A type"), 50 g of acrylic type 10 kg emulsion composition
After rotating for 5 minutes at a rotation speed of 1000 rpm under a pressure of / cm ² , the agglomerates in the container were filtered through a 100-mesh wire net and dried at 110 ° C. for 3 hours. The ratio to the amount was calculated by the following formula and used as an index of stability. Mechanical stability (%) = {Agglomerate dry weight (g) / [50
(G) x solid content concentration (wt%)]} x 100

The solid content is 110 ° C. when 1.5 g of the acrylic emulsion composition is placed in an aluminum cup.
After drying for 3 hours, the dry weight of the acrylic emulsion composition was measured and calculated from the following formula. Solid content concentration (wt%) = [dry weight (g) /1.5
(G)] × 100

[0044]

[Table 1]

[0045]

EFFECT OF THE INVENTION The acrylic emulsion composition of the present invention has the above-mentioned constitution. Even if a tackifier is added to the acrylic emulsion to improve the adhesive property, it has excellent mechanical stability (coating). Stability). Therefore, it can be suitably used for applications where high shearing force is applied.

Claims (1)

[Claims] 1. (A) Acrylic emulsion, (B)
An acrylic emulsion composition comprising a tackifier emulsion emulsified and dispersed with an anionic surfactant, and (C) a polyoxyethylene-based nonionic surfactant having an HLB of 10 to 20.