JPH0245586A - Resin composition for pressure sensitive adhesive - Google Patents

Abstract

PURPOSE:To obtain the title composition having good adhesion to nonpolar material to be bonded, balance of adhesion-cohesion and low-temperature adhesive by blending an aqueous dispersing element of copolymer having low styrene content with an aqueous dispersing element of copolymer having high styrene content at a specific ratio. CONSTITUTION:The aimed composition obtained by blending (A) an aqueous dispersing element of copolymer having low styrene content and obtained by copolymerizing (i) <10wt.% styrene with (ii) 40-90wt.% butadiene and (iii) 5-55wt.% butyl acrylate and/or 2-ethylhexyl acrylate as main components with (B) an aqueous dispersing element of copolymer having high styrene content and obtained by copolymerizing (i) 31-65wt.% styrene, (ii) 5-39wt.% butadiene and (iii) 5-30wt.% butyl acrylate and/or 2-ethylhexyl acrylate as main components at solid weight ratio of component A/component B of 95/5-5/95.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides adhesive and adhesive strength for non-inserted bamboo and incense bodies.
Pressure sensitive 1 with excellent cohesive force balance and low temperature adhesion. i.Regarding a durable resin composition. For more details,
7v rt suitable for paper labels, packaging T-bucks, cellophane/'-bucks, 7single labels, various slips, etc.
If: Regarding a resin silk composition for stone preparation.

(Conventional technique 1fi) Pressure-sensitive welding 4 conventionally used for paper labels, packaging j-busses, etc.
As the resin for the agent, solvent-type acrylic resin, soubrene-butadiene rubber, natural rubber, etc. are used in combination with a C-stone imparting agent as required.

However, due to the use of solvents, the use of solvent-based base resins is decreasing year by year due to pollution regulations, fire and explosion risks, health and safety issues, etc., and a shift is being made to aqueous dispersion-based base resins.

As such an aqueous dispersion type base resin, an aqueous dispersion of an acrylic co-market resin containing acrylic acid ester as a main component is used in a wide range of applications, but the disadvantages of this acrylic resin include: The adhesion of the monopolar adherend I\ is insufficient, and the balance between adhesion (tack) and cohesive force (holding force) is low. The disadvantage is that the holding force at high temperatures is low, and conversely, increasing the holding power at high temperatures lowers the low temperature tack.

Another drawback is that it is relatively expensive.

In terms of cost, it is advantageous to use an aqueous dispersion of sobren-butadiene as a base resin for adhesives. A pressure-sensitive adhesive emulsion comprising an aqueous emulsion of a water-based emulsion of a combination of a small silyl-sulfur-butadiene rubber and a tackifying resin is disclosed.

In this case, soubrene-butadiene copolymer 11i
In Germany, there is a problem with sticky bamboo, and in order to improve this drawback, it is necessary to add a large amount of adhesive (NI 9). Although this improves the adhesive strength, ,
Since the molecular weight of the adhesion agent (=J) is low, if it is used for polyr6, it will cause a decrease in cohesive force.

Furthermore, in order to produce the above-mentioned aqueous dispersion of the pressure-sensitive adhesive, in addition to the production of the aqueous dispersion of the base resin, the tackifier, which is generally solid at room temperature, must be emulsified to form an aqueous dispersion. This method requires several steps and is disadvantageous in terms of cost.

In addition, in this process, in order to stabilize the emulsion of the adhesive (45 agent) as an aqueous dispersion (2, 4 surfactants are required), it often has a low tack/adhesive force and a low water resistance. He became a 11j prisoner.

In some cases, a method is used in which the tackifier dissolved in the solvent is emulsified using a surfactant. -5 problems.

Due to the above-mentioned drawbacks, the actual situation is that the use of aqueous dispersions of sobren-butadiene T copolymer rubber is limited.

On the other hand, JP-A-57-57707, JP-A-56-1
Publication No. 45.909 discloses a pressure-sensitive adhesive using an aqueous dispersion of synthetic rubber as a base resin without using a tackifier.

These methods are characterized in that, in addition to soubrene and butadiylene, acrylic esters, particularly bubbly acrylate and 2-ethyl acrylate, are co-contained with A-sil in a specific composition range as a base resin.

[Problems to be solved by the invention]

The above method has the advantage of being more expensive than a pressure-sensitive adhesive using a water 4++ dispersion of acrylic resin as the base material (though it has the advantage that the balance between adhesive strength and cohesive strength is higher). is not improved.

Furthermore, there is a problem with the quality of coating T1P on labels, webs, etc.

That is, since it does not contain a sticky adhesive (generally a resin with a high softening point of 70 to 130°C) and has a soft rubber component as its main component, it is a pressure-sensitive adhesive whose base resin is an aqueous dispersion of the above-mentioned synthetic rubber. The so-called ``glue cutting'' is poor, and when applying it to labels, tapes, etc., and processing it in the punching T, die cut 1~, and slitter IW processes after it has dried, the pressure-sensitive adhesive is often cut off by the cutting blade, Otherwise, it may adhere to the cup 1 surface, contaminating it, or cause problems with the tongue, where the label cannot be peeled off as per the pattern.

The purpose of the present invention is to solve the above-mentioned problems and to provide a book with appetizers! The amount of filler compounded is greatly reduced or not required at all, it has high viscosity and adhesion to non-polar adherends, has an excellent balance of cohesive force with a thickness of 10,000 yen, is excellent for low-temperature sticky green bamboo, and has a 1r (Means for Solving the Problems) The present invention solves the above problems. In order to do so, we conducted a Q study. As a result, we have developed a pressure-sensitive adhesive that has excellent adhesion properties by mixing a butadiene copolymer with a low styrene content and a butane copolymer with a high styrene content. The present invention was completed based on the discovery that a resin composition for use in coatings can be obtained and, more surprisingly, the processability after coating is improved with this 62-coat system.

That is, the present invention provides (△) less than 1% by weight of styrene, 710~
90% by weight, butyl acrylate and/or 2-ethylhexyl acrylic liquor 5~□55+E fit% as one component and C copolymerized low-styrene-containing 4 with an aqueous dispersion of the polymer (B) styrene 31 ~65Φ hanging%, butadiene 5-
・An aqueous dispersion of a high sulfuric acid copolymer obtained by copolymerizing 39% by weight of butyl acrylate and/' or 2-ethyl acrylate with 5 to 30% by weight of -1sil as a main component. When the solid content Φ is suspended (A>/ (B)=9515~5.7・
A resin composition for pressure-sensitive adhesives consisting of 61 parts at a ratio of '95 parts.4 The present invention will now be explained in detail.

Is the low sobren-containing jJl-polymer used in the present invention an extreme example of J1? I! ! It is a component that describes the characteristics of chōseki, which is λ・1 in 4 bodies, J, and low E chōseki properties, and soubrene content 61 is 10
It is less than weight M%. However, from the viewpoint of compatibility with the high sobren-containing ladle copolymer, it is preferably 5% by weight or more. If the amount is 10% or more, the viscosity and adhesion to non-polar adherends will decrease, and the low-temperature adhesion will also decrease.

The content of butadiene is 40-90%, preferably 5%.
It is 0 to 80% by weight. If it is less than 40% by weight, it may not exhibit sufficient adhesion when mixed with a high styrene-containing copolymer, and if it exceeds 90% by weight, the cohesive strength, especially the holding power at high temperatures, may deteriorate. The C141 content of A-sil in butyl acrylate and/↑, or 2-ethyl acrylate is 5.~55 wt ω%, preferably 15'
-45% by weight. If it is less than 1% to 5,000, sufficient slate power will be 1q/r, and if it exceeds 55%, it will be disadvantageous in terms of price.

- 10,000, the high soubrene a-right and 0 combinations used in the present invention have high cohesive force and appropriate viscosity and adhesion, and have a component that has a high cohesive force and moderate viscosity and adhesion. 6%, preferably 35 to 60φ hanging %C.

31iIi Hanging%: 1 for cocoons, sufficient cohesive force was not obtained when mixed with low Slenium ah co-aggregate, and 65
To condolence) If you exceed %, your tenacity and contact ability may decrease significantly.

The content of butadiene is 5 to 391% by weight, and the content of butyl acrylate and/or 2-ethyl acrylate is 5 to 30% by weight, and both components are 51% by weight.
If the amount is less than 64, the compatibility may not be as high as I-minute when combined with a low styrene-containing copolymer.

If the butane content exceeds 39% by weight, sufficient cohesive force
qreji, butyl acrylate and/or acrylic liquor 2-1 1 sill is more than 30% by weight (b, sufficient cohesive force is 1'I/().

Aqueous dispersion (△) of low styrene content (1) and hess,
r-ren-containing 111, polymer water ze 1 dispersion (F3)
6 combination ratio (,1, solid content Φ1 excess ratio ′C-(△)′(11
)・9515-5/95, Ri-f, L L <
490, / 10 to 10/90 5, when the mixing ratio is over 9b, 15, the cohesive force is 1 minute or less, 1'
The holding power of high temperature C is low. Also, if it is less than :), y'95, the adhesive strength is insufficient, especially at low temperatures.

Examples of styrene, butane, butyl acrylate, and other 96 compounds that can be co-formed with (2-ethylhexyl acrylate) are: (meth)acrylic acid, ethylenically unsaturated carbon of itaconic acid γt Acid: Water M such as (meth)acrylic M2-hydro-t-ciple
IJ content hanging body (meth)acrylamide, N-mebrol (meth)acrylamide Yuki's unsaturated carbonamide and its N-
Substituted compounds: (meth)acrylonitrile containing functional groups usually used in emulsification procedures, such as glycidyl group-containing hollow bodies such as glycidyl (meth)acrylate-1, (meth)acrylonitrile etc. 21-ril l, < 4j (published hA (Thursday)
; Aromatic vinyl compounds such as α-methylstyrene and didonylbenzene; Vinyl compounds such as vinyl acetate and vinyl propionate; and butyl acrylate and acrylic compounds; Examples include (meth)acrylic acid esters other than lf2-r-Pruhexyl.

The aqueous dispersion (△) of a low styrene-containing copolymer used in the present invention (A3) and the aqueous dispersion (B) of a high 1-styrene-containing it/0 copolymer were prepared by a known emulsion polymerization method. There is no particular limitation as long as it is followed.

Examples of surfactants used in the tL reaction procedure include furkyl sulfurized nitrogen salts, alkyl benzene sulfonates,
Sial 1 Rusulfo] Haku MI sprue salt, Alt Luzif I
such as nil-1-terdisulfone MjW? Two-A bamboo surfactant, poly(A-xyethylene) full-gyl varnish, alkyl needle, and alkyl phenyl-based nonionic 1'/l active bamboo agent are used in medium or in combination of two or more. .

Examples of initiators include persulfate potassium \, persulfate 1
A redox system initiator γi in combination with a water-soluble initiator of leek 11 tongue or a reducing agent such as sulfite P/i salt is prepared.

As the molecular weight modifier, known chain transfer VJ agents such as mercaptans and Uiso halogen compounds such as tetrachloride derivatives can be used.

When used as a sweat-sensitive adhesive, the resin composition for pressure-sensitive adhesives of the present invention can be used as a thickener, antifoaming agent, i! In addition to various additives commonly used in pressure-sensitive adhesive formulations such as lubricants, anti-aging agents, and photosensitive adhesives, tackifiers, plasticizers, etc. can be added as necessary. be able to.

Examples of the tackifier include rosin type, rosin derivative type, terpene resin type, 6111181 fat type, )1nol resin type, etc., and it is usually added as an aqueous dispersion, but the amount added is determined according to the present invention. In accordance with the subject matter, it is limited to a relatively small number.

11 Specifically, the solid content and the amount of water (P1) as a tackifier per 100 parts of the composition for pressure-sensitive adhesives of the present invention are as follows.
Dispersion 40SSI is preferred.

- (Examples) Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

In addition, all parts and percentages in the actual example Il#i are based on small amounts.

(Production example (1) of aqueous dispersion of low styrene-containing copolymer
~(3)) 350 parts of water, 0.3 parts of dodecylbenginesulfone soda-resistant, and 6.0 parts of potassium persulfate were placed in an autoclave, and the inside of the autoclave was purged with nitrogen. 60℃ under stirring
) of the mixed upper emulsion shown in Table 1),
10% was charged and polymerization was carried out for 1.5 hours. Next, the remaining mixed monomer emulsion was added after being mixed for about 10 hours, and after polymerization for about 15 hours, it was cooled and 2.7 parts of di-L-purhydro-1-cyamine was added.

(Production example (a) of aqueous dispersion of co-(1) combination of comparative example) ([-1) + mixed E-sumer composition except that the compositions shown in Table 1 (a) to (b) were used. An aqueous dispersion of a low styrene-containing copolymer was prepared by the same person as in Preparation Examples (1) to (3).

(Preparation of aqueous dispersions of high styrene-containing copolymers IIA (
a> to (C)) Charge 365 parts of water, 0.8 parts of sodium dodecylbenzenesulfonate, 6.0 parts of itaconic acid, 30 parts of styrene, and 5.0 parts of 1M potassium peroxide in an autoclave, and z-t
- Replace the inside of the crepe with nitrogen. While stirring, the mixture was heated to 70°C and mixed for 1 hour.

Next, an emulsion of the mixed monomers shown in Table 1 was added for about 6 hours, and after stirring for about 10 hours, it was cooled and 2.7 parts of di-[delhydro-cyamine] was added.

(Production example (c) of a base dispersion of a copolymer as a comparative example) The composition shown in Table 1 (c) was used as a non-mixing composition. Preparation of dispersion
Δ Examples (a) to (C) and the same 67 people made the
lko.

(Examples 1-2) The aqueous dispersions of Production V14 (2) and (C) were combined at solid content/hair ratios of 80/20 and 70/30.

After each solution was adjusted to PL-18.5 with 8% aqueous and nitrogen water, unreacted T-cells were removed by steam stripping, and concentrated to a solid content of 50% using an evaporator.

Next, a small amount of Primal Δ5F60 (Nippon Acrylic Ne1!IJ) was added as a thickener to adjust the viscosity to about 5,000 centipoise.

This was coated on release paper (coating amount: 60 q/day) and dried at 100°C for 3 minutes (applying paper was applied to the coated surface) to form a 1118 adherent layer. A sample C was prepared by transferring it to paper.The following physical properties were measured for this test piece.

The results are shown in Table 2.

(The following 7J method was used to measure the physical properties.) 1. Adhesive Crab 1] 2.5co+ test piece was polyersin root (height 10 cm, width 4 cttr, FJ diameter 2 ays)
with a constant repulsive force (load of 2 kg).
Pass it twice) and paste it (=IL/ko.

The tensile strength when peeled at 1800°C in an atmosphere of 20°C was measured.

Pulling speed: 300 m/min2, Sticky horn (tank): Inclined pole tack (,
According to the LDo-method), the inclination angle is 30°, the approach distance is
10 Measure and indicate the maximum diameter of the sunless sphere that stopped on the pressure-sensitive adhesive layer by 1 point every 1/32 inch. (For example, 2/32 in f is 2.10
/32 inch is displayed as 10. ) Measurement is 20'CJ
-5J and O'C atmosphere.

3. Cohesive force (holding force): A test piece with a width of 2.5 mm was brought into contact with a surface-polished stainless steel plate over an area of 2.5 C shoes x 2.5 cm, and the test piece was placed under constant pressure (passed twice through a 2 kg roll). affixed with).

This is hung vertically and a load of 1 K'J is applied to the bottom end.
Leave it standing in an atmosphere of 20°C or 60°C until the load drops.
The time it took to do so was measured and expressed in minutes.

4. Processability: The pressure-sensitive adhesive layer is sandwiched between high-quality paper and release paper.Itl 5 cm? 7) When 20 test pieces were piled up and cut with a push-cut cutter, the state of healing between Test 11 (4) or the state of contamination of the blade by pressure-sensitive stone (1) was visually determined.

◎: Fairly good, 0: Good (lf △: Slightly poor, ×: Poor (Comparative Examples 1 to 2) Except for using the aqueous dispersions of Production Examples (2) and (C) alone, Sensitive adhesive test pieces were prepared and tested in the same manner as in Examples 1 and 2. The results are shown in Table 2.

(Comparative Example 3) Aqueous molecule l1 of vJ production example (2) and comparative production example (c)
Example 1 and Example 2 were carried out in the same manner as in Example 1 and 2, except that the solids were heated at a solids ratio of 70/'30;
Fish juice adhesion test 11 was created and tested.

Show the results to Person 2.

(Examples 3 to 5) Production example (1) J3J, lrl ratio in solid content of aqueous dispersion of <b>'40 /60.50 /'50.60
//10 The reaction test F was carried out in the same manner as in Examples 1 and 2, except that the mixture was mixed.
Conduct the test. The results are shown in Table 2.

(Example 6 - ε3) The aqueous dispersion of Example 6 (3) and (b) was mixed with a solid content of 1 p.
The same method as in Examples 1 and 2 was used except that the early ratio was 50150.60/40.70/30.
A pressure-sensitive stone-bamboo test was created and tested in France.

The results are shown in Table 2.

(Comparative Examples 4 and -6) Except that each of the aqueous dispersions of Production Examples (1), (3), and (b) was used alone, 7J The pressure-sensitive stone test J-, was completed in accordance with the law, and the test was conducted.

The results are shown in Table 2.1゜(Comparative Examples 7 to 8) Comparative Production Example (A) or (【'') Aqueous Dispersion and Preparation Convex w
+ < b ) with an aqueous dispersion of solid content Φ; 41 ratio (
・Except for heating at 60, /'40 or 50150,
Implementation 1+1+ A bamboo test j4 was prepared and tested using the same j) method as shown in 1-2.

The results are shown in Table 2i.

(Examples 9 to 11) The aqueous dispersions of Production Examples (2) and (a) were mixed at a solid content of Φ of 10/90.20/80.30/70. After adjusting the pI to -18 with 20% KOH, unreacted isomer was removed by steam stripping, and the mixture was concentrated to a solid content of 1) 0% using an evaporator. Dolol (aqueous dispersion of glycerin ester of hydrogenated rosin: solid content 50%, resin softening point 7
1 to 78°C (manufactured by Nika Hercules) were blended in a solid content ratio of 100/20. Except for this, a test specimen was prepared and tested in the same manner as in Examples 1 and 2.

The results are shown in Table 2.

(Comparative Examples 9-10) Using the aqueous dispersions of production VA (2) and (a), 1. , : The method was the same as the method shown in Examples 9 to 11, except for the following steps.
1. :,.

The binding is shown in Table 2.

〔Effect of the invention〕

As is clear from the Examples and Comparative Examples, a pressure-sensitive stone contact agent obtained by mixing the aqueous dispersion (Δ) 33 of the low styrene-containing copolymer of the present invention and the aqueous dispersion (B) of the high styrene-containing copolymer The resin composition for use in the present invention cannot be obtained when an aqueous dispersion of the copolymer (Δ) or (13) is used alone, or when an aqueous dispersion of a copolymer outside the composition range of the present invention is mixed. It is clear that an excellent balance of four-car cohesive strength is achieved while providing ten times higher adhesion to non-polar adherends.

The stone-sensitive stone-sensitive adhesive formulation using the resin composition for adhesives of the present invention has good processability during coating and drying, and is relatively inexpensive, so the significance of the present invention is significant. Sai.

Claims (1)

[Claims] (A) Styrene less than 10% by weight, butadiene 40-90%
% by weight, butyl acrylate and/or acrylic acid2
- An aqueous dispersion of a low styrene-containing copolymer copolymerized with 5 to 55% by weight of ethylhexyl as a main component, and (B) 31 to 65% by weight of styrene and 5 to 39% of butadiene.
% by weight, butyl acrylate and/or acrylic acid2
- an aqueous dispersion of a high styrene-containing copolymer copolymerized with 5 to 30% by weight of ethylhexyl as a main component, in a solid content weight ratio of (A)/(B) = 95/5 to 5/95; A resin composition for pressure-sensitive adhesives prepared by mixing