JPS62295979A - Hot-melt adhesive composition - Google Patents

Abstract

PURPOSE:To obtain the title composition having excellent heat resistance, by mixing a hot-melt adhesive, a radical-polymerizable, UV-curing composition, and a specified photopolymerization initiator. CONSTITUTION:A hot-melt adhesive (A) is obtained by mixing a thermoplastic block elastomer (a) of formula I or II (wherein A is a PS block of a molecular weight of 2,000-12,500; B is a polybutadiene block, polyisoprene block or ethylene-butylene copolymer block of a molecular weight of 1,000-250,000), a synthetic rubber (b), a polyolefin (copolymer) (c), a tackifier (d), and a softening agent (e). 100pts.wt. component A is mixed with 0.1-200pts.wt. radical- polymerizable, UV-curing resin composition (B) comprising radical-reactive organic compounds (e.g., a composition comprising a polybutadiene oligomer having terminal acryloyl groups, and trimethylolpropane trimethacrylate), and 0.5-10wt% photopolymerization initiator (C) comprising a bis[alkoxysilyl)alkyl] disulfide or tetrasulfide.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention Industrial Field of Application The present invention relates to a hot-melt adhesive composition, specifically, a hot-melt adhesive containing a UV (ultraviolet) curable resin composition. The present invention relates to a composition in which bis[(alkoxyl)alkyl] disulfide, Δ, or tetrasulfide compound is blended as a compound and a photopolymerization initiator, and this is cured by UV irradiation, thereby improving the heat resistance of the composition.

Conventional technology and problems to be solved Sotome J Retouchi eJJt-@Mello l/ln11τ?
In the field of manufacturing optical discs, which is solvent-free and has fast curing properties, adhesives (abbreviated as "A") have been replaced with conventional epoxy adhesives and solvents due to their ease of use and other advantages. It is attracting attention as an alternative to mold adhesives.

However, a drawback of this HNIA is that it lacks heat resistance, and in particular, it is difficult to strike a balance between coating performance and heat resistance, which limits the scope of use of the adhesive.

The present inventors conducted extensive studies to improve thermal properties in such HMAi, and as a result 1-I to I A t. It was discovered that by blending a [(alkoxysilyl)alkyl] disulfide or tetrasulfide compound and irradiating it with UV, an adhesive film with excellent heat resistance could be formed while maintaining coating performance, and the present invention was completed. I ended up doing it.

Structure and Effects of the Invention Namely, the present invention provides a hot-melt type product comprising a radical conjugated UV curable resin composition and a bis[(alkoxysilyl)alkyl]disulfide or tetrasulfide compound in H to IA+. An adhesive composition is provided.

The present invention; this hot melt adhesive composition is based on common components for HMA. Such a base component has adhesiveness at room temperature and has the formula: % formula % [wherein A is a polystyrene block with a molecular weight of 2,000 to 12,500, and B is a polystyrene block with a molecular weight of 1,000 to 250,000].
polybutadiene block, polyisoprene block, or ethylene-butylene copolymer block] or one or more of the block-shaped thermoplastic elastomers shown in , butyl rubber, etc.),
Polyolefin or polyolefin copolymer (polyethylene, polypropylene, ethylene-vinyl acetate copolymer, etc.), tackifier (rosin resin, petroleum resin, terpene resin, phenol resin, coumaron resin, etc.), softening agent (process oil) , paraffin oil, castor oil, etc.) is preferably added.

On the other hand, the radical polymerization type UV added to this base component
The curable resin composition consists of a radically reactive organic compound.

The above-mentioned radical-reactive organic compounds include radical-reactive oligomers (such as double-terminated acryloyl polybutadiene oligomers, epoxy acrylic oligomers, urethane acrylic oligomers, polyester acrylic oligomers, alkyd acrylic oligomers, and silicone acrylic oligomers) and polymers that impart a crosslinked structure. Functional (meth)acrylic monomer [trimethylolpropane tri(meth)
Acrylate, penta-triacrylate, ethylene glyfur di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexane Shiorji (
Meta) acrylate.

Non-opentyl glycol di(meth)acrylate.

diacryloxyethyl phosphate, etc.], and this reactive diluent monomer (vinylpyrrolidone, diacryloxyethyl phosphate etc.) is essential.
-Hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, tetrahydrofurfuryl acrylate, butoxyethyl acrylate, ethyldiethylene glycol acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenoxyethyl acrylate, 2-hydroxy- 3-phenyloxypropyl acrylate, dicyclopentadiene acrylate, etc.) are added as necessary. The total amount of the radical-reactive compound used is usually 0.00 parts per 100 parts (1 part of chewing, same hereinafter) of the base component.
The amount may be selected within the range of 1 to 200 parts, preferably 5 to 100 parts.

In addition, bis[(alkoxyl 1111, S7
゛Poor 7 Le 7 Sue 11.1 Dot + Thousand 1
→Purphyto compounds can be produced by various methods.

For example, West German Patent Publication Nos. 2141159 and 214
No. 1160 describes a method for producing a mixture of tri- or tetrasulfides at the same time as producing a disulfide compound represented by the formula: %Formula % (R is alkyl having 1 to 4 carbon atoms). Also, Japanese Patent Application Laid-Open No. 50-84534 N +
Also, r-mercaptopropyltrialkoxysilane is reacted with sulfuryl chloride.

A method for obtaining disulfide compounds is described.

Furthermore, there is a method of producing a high purity disulfide compound conveniently and in high yield using mercaptoalkylalkoxysilane, sodium alcolade and iodine as reaction reagents. In the formula, λ and R2 are the same or different and are lower alkyl having 1 to 4 carbon atoms, R3 is lower alkylene having 1 to 4 carbon atoms, and n is Oll or 2.] A mercaptoalkylalkoxysilane of the formula: In the formula, R1 has the same meaning as above] By reacting with sodium alcoholade and then with iodine, bis[, where R1, R2, R3 and n have the same meaning as above] (Alkoxysilyl)alkyl]disulfide is obtained.

The amount of such a photo-initiator to be used may normally be selected within the range of 0.5 to 10% by weight based on the total amount of the radically reactive organic compound.

As described above, the hot melt adhesive composition according to the present invention comprises the above-mentioned base component 1, a radically reactive organic compound, and a bis[(alkoxysilyl)alkyl]disulfide or tetrasulfide compound as a photopolymerization initiator in a predetermined ratio. It is composed of a system in which ordinary fillers, anti-aging agents, polymerization inhibitors, etc. are added as necessary.
It is melted at a temperature of 0 to 180°C and used. In addition, the melt viscosity is generally 5000 to 2000 Ocp at 120°C.
S number is set.

The hot-melt adhesive composition of the present invention can be bonded in the following manner. First, the adhesive composition is melted and applied to the adhesive surface of the adherend to a thickness of 5 to 100 μm, and then UV irradiated for 10 to 30 seconds, and the adherend is placed on the surface to give a thickness of 0.2 μm. Press at ~2.0 KIi/m, or irradiate with UV after pressing. In this way, the heat resistance of conventional HNIA can be improved.

Next, the present invention will be explained in more detail with reference to Production Examples and Examples.

Production Example 1 Production example of bis[γ-(trimethoxysilyl)propyl]disulfide - 28% methanol solution of sodium methylate 97.6
9 (0.51 mol) was diluted with 10 ome of methanol, and to this was added γ-mercaptopropyltrimethoxysilane L.
Add oop (0.51 mol) and mix. The temperature of the liquid will rise somewhat due to the heat of mixing, but it will return to room temperature in about 30 minutes. Next, iodine 64.6P (0.51 mol) is added little by little while stirring. Heat will be generated at this time, so cool the area around the container with cold water if necessary. When the entire amount of iodine was added, the reaction solution turned brown, but when left at room temperature for 3 hours,
It becomes a pale yellow transparent liquid. This is transferred to an eggplant-shaped flask, and the methanol solvent is distilled off under reduced pressure using a rotary evaporator. White crystals and oily pale yellow liquid remain in the flask. Next, the oily liquid of 86.49 is separated by door paper to obtain a bis[γ-(trimethoxysilyl)propyl disulfide compound.

Example 1 Adhesive composition Polystyrene-polyisoprene-polystyrene block thermoplastic elastomer (manufactured by Shell Oil Co., Ltd., Cariflex TR-1107, melt viscosity (140°C): 15
10,000 cps] ---1000 parts acryloyl polybutadiene oligomer at both ends --10 parts trimethylolpropane trimethacrylate --2
Bis[γ-(trimethoxysilyl)propyl disulfide compound of Production Example 1---0.6 parts Note) Melt viscosity of the adhesive (120°C): 10000 cPs Two acrylic plates (25 x 100 x 2.5 parts) ), melt the adhesive of the above composition at 120℃ and apply it to a thickness of 15μ with a trowel, irradiate it with UV for 20 minutes, immediately put it together and press it at 0.5 to 9/crd. do. The obtained laminated board was subjected to 1 heat resistance creep test (load 15
0y, vertical fall time).

The results are shown in Table 1.

Comparative Example 1 The same procedure as in Example 1 was carried out except that UV irradiation was omitted.

Comparative Example 2 Example 1 is carried out in the same manner as in Example 1 except that Cariflex TR-1107 alone is used as the adhesive and UV irradiation is omitted.

Table 1 From the results in Table 1, Example 1 had better adhesion to the acrylic board than Comparative Examples 1 and 2.

Claims (1)

[Claims] 1. In hot melt adhesive, radical polymerization type U
V-curable resin composition and bis[(alkoxysilyl)
1. A hot-melt adhesive composition comprising a [alkyl]disulfide or tetrasulfide compound.