JPS62158770A - Pressure-sensitive adhesive - Google Patents

Abstract

PURPOSE:To obtain a pressure-sensitive adhesive which has excellent adhesiveness, blocking resistance, abrasion resistance, heat resistance, etc. and is suitable for sticking of, e.g., a letter form sealed by folding in three, by incorporating a trackifier and a silica gel in specified weight ratios into an SBR latex. CONSTITUTION:50-200pts.wt. trackifier (e.g., a rosin or a polyterpene resin) is added to 100pts.wt. SBR latex to improve the adhesive power and the long- term stability thereof, to which 5-40pts.wt. fine powder of silica gel is added to improve the blocking resistance, abrasion resistance, etc., thus giving an objective pressure-sensitive adhesive. As the silica gel, a fine powder having an average particle diameter of about 1-10mum is preferable. If necessary a dispersing agent, a wetting agent, a thickening agent, an anti-foaming agent, etc., can also be added to the SBR latex in addition to the tackifier and silica gel.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is characterized in that a predetermined portion of a printing form such as paper or a form on which information is printed is coated in advance.
This is a pressure-sensitive adhesive for binding printed forms together by applying pressure, which is the adhesive condition for post-adhesives. It is used as an adhesive for pasting together cards, etc., or as an adhesive for binding booklets, etc.

[Prior art and its problems] Conventionally, natural rubber, synthetic rubber,
There were some whose main ingredients were synthetic resins, etc., and they were selected and used depending on the purpose.

In recent years, many printers called non-impact printers have begun to be used, and printers that use electrophotographic recording methods, which are a type of non-impact printer, fix toner by heat and pressure bonding, so thermoplastic C1L is a pressure-sensitive adhesive whose main components are synthetic rubber or synthetic resin, and the adhesive softens inside the printer, causing problems such as the softened adhesive adhering to the printer, which is an inconvenience.

In addition, pressure-sensitive adhesives whose main ingredient is natural rubber are inconvenient, as the surface strength of the 1a adhesive is low, leading to accidents such as adhesive adhesion inside the printer and damage to the printer. .

Furthermore, when the above-mentioned conventional pressure-sensitive adhesives are applied to printing frames, they are not satisfactory in adhesion, heat resistance, blocking resistance, and storage stability.

[Means for Solving the Problems] As a result of extensive research, the present inventor improved the adhesive strength by adding a tackifier to SBR latex,
Furthermore, silica gel fine powder is added to improve blocking resistance.
The inventors have discovered that an excellent pressure-sensitive adhesive can be obtained by improving abrasion resistance and heat resistance, and have completed the present invention.

In the present invention, 50 to 200 parts by weight, preferably 100 to 150 parts by weight of tackifier to 100 parts by weight of SBR latex.
It was found that the adhesive strength of the mounting part improved dramatically when the heavy hanging part was added, and the long-term stability of the adhesive strength also improved. Further, 5 to 40 parts by weight, preferably 5 to 40 parts by weight, of fine silica gel powder with an average particle size of 20 μm or less, preferably 1 to 10 μm, more preferably 2 to 6 μm, is added to 200 parts by weight of the mixed solution of S B 11 latex and tackifier. By adding 15 to 30 parts by weight, adhesive strength,
We were able to obtain a pressure-sensitive adhesive that dramatically improved heat resistance, abrasion resistance, blocking resistance, and storage stability, and had superior performance compared to conventional pressure-sensitive adhesives.

The SBR latex and silica gel according to the present invention are
As described in the examples, various styrene ratios and particle sizes can be applied, especially those with an average particle size of 1 to 1.
Products containing 15 to 301 t parts of silica gel of 0μ per 100 parts weight of SBR latex have particularly excellent adhesive properties and are suitable for use in mailing envelopes, postcards, and various cards, and are suitable for use in other applications. The pressure-sensitive adhesives described in the examples can also be used advantageously depending on the application, such as adhesion and binding of paper and forms.

Even if SBR latex is applied to paper as a pressure-sensitive adhesive and dried, the adhesives are brought into contact with each other and pressure is applied, the adhesiveness is weak, but the pressure-sensitive adhesive of the present invention contains 100 parts by weight of SDR latex. By adding 50 to 200 parts by weight of a tackifier and 5 to 40 parts by weight of silica gel, various effective performances as a pressure-sensitive adhesive can be exhibited. Moreover, as shown in FIG.
The surface of the pressure-sensitive adhesive 2 coated to a thickness of μ is formed into an uneven shape by the silica gel 3.

In addition, the tackifier used in the present invention includes rosin, modified rosin and derivatives thereof, polyterpene resin,
Included are modified terpenes, aliphatic hydrocarbon resins, cyclopentadiene resins, aromatic petroleum resins, phenolic resins, alkylphenol/acetylene resins, styrene resins, xylene resins, and coumaron indene resins.

Further, the pressure-sensitive adhesive of the present invention is made by adding a tackifier and silica gel to SBR latex, but depending on the essence, a dispersant, wetting agent, binder, antifoaming agent, etc. can also be blended.

[Example] Next, the present invention will be described in more detail with reference to Examples.

Since it is clear that widely different embodiments may be constructed without departing from the spirit and scope of the invention,
The invention is not limited to these specific embodiments except as limited in the claims below.

Note that throughout this specification, all parts refer to heavy items. Further, various performances of Examples and Comparative Examples were measured by the following method using a sheet of paper coated with a pressure-sensitive adhesive to a thickness of about 5 μm.

A sealing machine for adhesive Niprint form pressure bonding was used. The applied force is approximately 100 to 9/ci.

Peeling resistance: Peeling resistance: 11 JI test using a tensile universal tensile tester after leaving for 1 ci while applying a load of about 500 g/7 in a constant temperature bath at various temperatures from 30° to 70° C. I did it.

jfA abrasion resistance: The adhesive surface was abraded while applying a load of 9/cd to 200 to 500, and the strength of the adhesive surface was examined.

Heat resistance: 1-3 Kl/ci detention, adhesive side 20
The surface condition of the IBV agent was examined by applying heat to 0°C.

Example 1 313R latex "Crosren S^-23" (product name; manufactured by Narita Pharmaceutical Co., Ltd., styrene ratio 30%, solid content 48
%) 100 Apply tackifier [Nobuco [8J (product name: manufactured by San Nobuco Co., Ltd., ester rubber type, solid content 46%] to the severely affected area)
Add 100 ffiffi parts to prepare mixed solution A.

Furthermore, 20,25,30 parts of silica gel [Thyroid 404J (trade name; manufactured by Fuji Davison Chemical Co., Ltd., particle size 10μ) was added to 11 parts of the mixed solution Δ200tJ to prepare pressure sensitive adhesives a, b, and c, respectively. .

Example 2 SBR latex [Crossren S^-20] (product name;
Tackifier [Nobuco EB-I J (trade name; manufactured by San Nobuco Co., Ltd., aliphatic petroleum hydrocarbon resin type, solid content 46%) 1
00 parts by weight to prepare a mixed solution B. Furthermore, the mixed liquid B
Silica gel "Thyroid 404" in 1 part of 200mff
were added in an amount of 20.25.30 parts by weight to form pressure-sensitive adhesives d, e, and f, respectively.

Example 3 S[3R Latex rJsR0596J (trade name: manufactured by Nippon Synthetic Rubber Co., Ltd., solid content 50.5%) 100-layered tackifier rEBJ (trade name: manufactured by San Nobuco Co., Ltd., ester gum type, solid content 46%) Add 100 parts by weight to 1 part of the mixed solution C and 16° to 1 part of the mixed solution)
J) j ru rat i 0 it 404J wo 20.25.30
71 parts m of 1i were added to give pressure sensitive 1 & adhesive Ω, h, 1, respectively.

Example 4 SBR latex "JsII 05GIJ (product name: manufactured by Japan Synthetic Rubber Co., Ltd., styrene ratio 24.5%, solid content 69%)" tooLfM811 and tackifier "Pentalint 1" (product name: manufactured by Rika Vercules Co., Ltd., water Added rosin pentaerythritol ester) dispersion 100f
Add p-hang part to make a mixed liquid. Further, the 8 mixture D2
00 parts by weight of silica gel JSI PERNAT 22SJ
(Product name: Nippon Aerosil Co., Ltd., particle size: 5μ, 20.
25. Add 30 overlapping parts to pressure sensitive adhesive j, respectively,
It was set as I.

Example 5 Part of SBR Latex R JSR0561J 100 heavy suspension tackifier [Foral 105J (trade name; hydrogenated rosin pentaerythritol ester type, manufactured by Rika Herkikores Co., Ltd.) dispersion ioo@a was added to prepare a mixed solution E. Add silica gel R 5I to the mixture E 200
20, 25, and 30 parts of PERNAT 22SJ were added to form pressure sensitive adhesives m, n, and o, respectively.

Comparative Example 1 Tackifier [
Hytanol 1501 J (product name; manufactured by Hitachi Chemical Co., Ltd.)
Tripartite was added, and 10 parts by weight of casein were added to prepare a pressure-sensitive adhesive p.

Comparative Example 2 Pressure-sensitive adhesives q, r, and s were prepared in the same manner as in Example 1 except that the tackifier "Nobuco EB J" was not used.
And so.

Comparative Example 3 A pressure-sensitive adhesive t was prepared in the same manner as in Example 1, except that 3.5 parts by weight of silica gel "Syroid 404" was added.

Comparative Example 4 Pressure-sensitive adhesive U was prepared in the same manner as in Example 1, except that Silica Gel R Thyroid 404J was added to the hanging portion of 43.5Φ.

Pressure sensitive adhesives a to 0 of the present invention prepared in Examples 1 to 5 above
Table 1 shows the test results of the adhesiveness, blocking resistance, heat resistance, and abrasion resistance of the pressure sensitive adhesives PU prepared in Comparative Examples 1 to 4.

[Effects of the Invention] As is clear from Death 1 to Conclusion, the pressure-sensitive adhesive of the present invention has excellent performance in all items of adhesiveness, blocking resistance, heat resistance, and abrasion resistance. It is something.

Therefore, the sensitive adhesive of the present invention can be applied to a three-fold envelope form 4 shown in FIG. 2, which is a type of printing form.
It is particularly effective to apply the pressure-sensitive adhesive 2 of the present invention to a thickness of about 3 to 6 μm in advance on the adhesive part of the double-ply letter form 5 shown in FIG. 3
In addition to the printing form shown in the figure, it can be applied in advance to printing forms such as tri-fold i>j tl form, postcard form, various notification forms, binding form, J: and window-perforated tri-fold 14 store form. It is effective for use as a

[Brief explanation of drawings]

Figure 1 is an explanatory diagram showing the state in which the pressure-sensitive adhesive of the present invention is applied onto a printing form. Figure 2 is an explanatory diagram showing the pressure-sensitive adhesive of the present invention applied to a tri-fold envelope form, which is a type of printing form. FIG. 3 is an explanatory diagram showing the state in which the pressure-sensitive adhesive of the present invention is applied to a form for double-ply envelopes, which is a type of form for printing. 1... Printing foam 2... Pressure sensitive adhesive 3... Silica gel 4...
・Form 5 for tri-fold envelopes...Form 6 for double-layer injection...Perforation for folding 7...Sewing machine for cutting 1
8... Perforation for opening patent applicant Totsuban Mu 7 Co., Ltd. [Figure 1 Figure 2

Claims (1)

[Claims] SBR latex 100 parts by weight, tackifier 50-20
0 parts by weight and 5 to 40 parts by weight of silica gel.