JP2021004272A - Seal material - Google Patents

Abstract

To provide a seal material which has good followability and high adhesive force to a rough concrete surface.SOLUTION: Provided is a seal material 1 comprising: a substrate 3 formed of a foamed body and a first adhesive layer 5 arranged on at least one surface side of the substrate. The adhesive layer 5 comprises an adhesive containing as a raw material a raw material composition containing a urethane prepolymer, a polythiol, a compound containing a plurality of photoreactive functional groups, and a tackifier. The urethane prepolymer contains as raw materials a polyol, a polyisocyanate, a monool not containing a photoreactive functional group, and a monool containing a photoreactive functional group.SELECTED DRAWING: Figure 1

Description

The present invention relates to a sealing material.

A sealing material in which an adhesive layer is provided on a base material made of a foam is known. This sealing material is attached to concrete and used for the purpose of stopping water, for example, at a civil engineering work site.
By the way, as the adhesive material for concrete, rubber-based or acrylic-based adhesive materials are mainly used (see, for example, Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 8-3-19462 JP-A-2002-363529

However, since concrete has irregularities on its surface and concrete dust and dust are scattered, the conventional sealing material using an adhesive material does not always have sufficient followability to a rough surface, and these The adhesive strength of the sealing material is not always sufficient, and a new sealing material has been eagerly desired.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a sealing material having good followability to a rough surface of concrete and high adhesive strength. The present invention can be realized as the following forms.

[1] A base material made of foam and
A sealing material (adhesive sealing material) including an adhesive layer provided on at least one side of the base material.
The pressure-sensitive adhesive layer comprises a pressure-sensitive adhesive made from a raw material composition containing a urethane prepolymer, a polythiol, a compound containing a plurality of photoreactive functional groups, and a pressure-sensitive adhesive.
The urethane prepolymer contains a polyol, a polyisocyanate, a monool containing no photoreactive functional group, and a monool containing a photoreactive functional group as raw materials.
A sealing material characterized by that.

[2] The ratio of the equivalent number (c) of the thiol group contained in the polythiol to the equivalent number (d) of the double bond of the total photoreactive functional group contained in the urethane prepolymer and the compound {( The sealing material according to [1], wherein c) / (d)} is 0.7 to 2.5.

[3] The ratio {(a) / (b)} of the equivalent number (a) of the photoreactive functional group existing at the end of the urethane prepolymer to the equivalent number (b) of the photonon-reactive functional group is 0. .4 to 2.5,
The total double bond amount (mol / kg) per unit mass representing the double bond amount of all the photoreactive functional groups contained in the urethane prepolymer and the compound is 0.1 to 0.5. ,
The sealing material according to [1] or [2], wherein the compounding amount of the compound is 0.3 parts by mass or more with respect to 100 parts by mass of the urethane prepolymer.

[4] The item according to any one of [1] to [3], wherein the blending amount of the tackifier is 5 to 30 parts by mass with respect to 100 parts by mass of the urethane prepolymer. Sealing material.

[5] The sealing material according to any one of [1] to [4], wherein the foam has a skin layer on its surface.

[6] The foam has a density of 20 to 200 kg / m ³ .
The sealing material according to any one of [1] to [5], which has a 25% compressive hardness of 30 to 350 kPa.

[7] The second pressure-sensitive adhesive layer and the support are arranged in order from the base material side between the base material and the pressure-sensitive adhesive layer [1] to [6]. The sealing material according to any one item.

The sealing material of the present invention has good followability to the rough surface of concrete and has high adhesive force to concrete.

It is sectional drawing which shows typically the structure of an example of a sealing material. It is sectional drawing which shows typically the structure of an example of the sealing material of another form. It is a schematic diagram which shows the structure of the urethane compound contained in a urethane prepolymer. It is a schematic diagram which shows the measuring method in the concrete peel strength measurement. It is a schematic diagram which shows the measuring method in heat resistance holding power measurement.

Hereinafter, the present invention will be described in detail. Unless otherwise specified, the notation indicating the range "x to y" shall include x and y in the range.

1. 1. Sealing material 1
As shown in FIG. 1, the sealing material (adhesive sealing material) 1 includes a base material 3 made of a foam and a pressure-sensitive adhesive layer 5 provided on at least one side of the base material 3 (hereinafter, “first pressure-sensitive adhesive”). (Also referred to as layer 5). The sealing material 1 may be provided with the first pressure-sensitive adhesive layer 5 on both surfaces of the base material 3.
Further, as shown in FIG. 2, the sealing material 1 is formed between the base material 3 and the first pressure-sensitive adhesive layer 5, in order from the base material 3 side, the second pressure-sensitive adhesive layer 7 and the film-like support 9. May be arranged.
In FIGS. 1 and 2, reference numeral 2 indicates concrete which is a typical adherend (adhesive body).
The material of the second pressure-sensitive adhesive layer 7 is not particularly limited, but the material of the second pressure-sensitive adhesive layer 7 is preferably the same as that of the first pressure-sensitive adhesive layer 5 from the viewpoint of simplifying the configuration. The material of the film-like support 9 (thin-film support) is not particularly limited, and for example, a thin film-like paper, a known resin film (PET film, OPP film, etc.), or a resin foam sheet may be used. it can.
The thickness (total thickness) of the sealing material 1 is not particularly limited.
The thickness of the base material 3 is not particularly limited. The thickness of the base material 3 is preferably 3 mm or more, more preferably 5 mm or more, from the viewpoint of rough surface followability (seal) with the base material. On the other hand, the thickness of the base material 3 is preferably 200 mm or less, more preferably 150 mm or less, from the viewpoint of the concrete injection thickness of the concrete structure. From these viewpoints, the thickness of the base material 3 is preferably 3 mm to 200 mm, more preferably 5 mm to 150 mm.
The thickness of the first pressure-sensitive adhesive layer 5 is not particularly limited. The thickness of the first pressure-sensitive adhesive layer 5 is preferably 10 μm or more, and more preferably 30 μm or more, from the viewpoint of ensuring the peel strength while sufficiently providing the rough surface followability to concrete. On the other hand, although the adhesive strength does not change so much even if the thickness of the first pressure-sensitive adhesive layer 5 is increased, 500 μm or less is preferable, and 300 μm or less is preferable from the viewpoint of suppressing the bulk of the first pressure-sensitive adhesive layer 5 and the manufacturing cost. Is more preferable. From these viewpoints, the thickness of the first pressure-sensitive adhesive layer 5 is preferably 10 μm to 500 μm, more preferably 30 μm to 300 μm.
The thickness of the second pressure-sensitive adhesive layer 7 is not particularly limited, and can be, for example, 10 μm to 500 μm.
The thickness of the film-shaped support 9 is not particularly limited, and can be, for example, 10 μm to 200 μm.

(1) Base material 3
The material of the foam constituting the base material 3 is not particularly limited. As the material of the foam, polyurethane foam, rubber sponge, polyolefin foam (for example, polyethylene foam) and the like can be preferably mentioned.
The foam preferably has a density (JIS K7222: 2005) of 20 to 200 kg / m ³ and a 25% compression hardness (JIS K6400-2: 2004 D method) of 30 to 350 kPa. By using a foam in this range, a sufficient water-stopping function can be obtained in a water-stopping application, for example, a building civil engineering application, and a good handle-length property can be obtained because it is flexible.
Further, the foam may be provided with a skin layer on the surface thereof. The skin layer is formed into a dense film by compressing the bubbles or by reducing the bubble size, and has high smoothness and is not easily torn. Therefore, the water permeability is low, and the sealing property is improved when used for preventing water leakage of concrete.

(2) First adhesive layer 5
The first pressure-sensitive adhesive layer 5 comprises a pressure-sensitive adhesive made from a raw material composition containing a urethane prepolymer, a polythiol having a thiol group, a compound containing a plurality of photoreactive functional groups, and a pressure-sensitive adhesive. ..
The first pressure-sensitive adhesive layer 5 is characterized in that it is crosslinked and cured by an en-thiol reaction between a urethane prepolymer having a photoreactive functional group and a polythiol having a thiol group. Therefore, it can be prepared without using a solvent, and since oxygen inhibition does not occur during curing, it is not necessary to install a cover film or work in a nitrogen atmosphere when curing by light irradiation.

(2.1) Raw Material Composition (2.1.1) Urethane Prepolymer Urethane prepolymer is a polyol, a polyisocyanate, a monool containing no photoreactive functional group, and a monopolymer containing a photoreactive functional group. All is included as a raw material. That is, the urethane prepolymer is derived from a structure derived from a polyol, a structure derived from polyisocyanate, a structure derived from monool containing no photoreactive functional group, and a monool containing a photoreactive functional group. Has a structure.

In the urethane prepolymer, the following four types of urethane compounds can be produced. Therefore, the prepolymer in the present invention contains one or more of the following four types of urethane compounds. The prepolymer is, for example, a mixture containing a plurality of the following four types of urethane compounds.
[1] A urethane compound produced by a urethane reaction between a polyol, a monool containing a photoreactive functional group, and a polyisocyanate, that is, a photoreactive functional group in which all terminals present in a plurality of urethane compounds are reactive. The base urethane compound.
[2] Among the urethane compounds produced by the urethane reaction of the polyol, the monool containing no photoreactive functional group, the monool containing the photoreactive functional group, and the polyisocyanate, a plurality of urethane compounds. A urethane compound having a reactive photoreactive functional group at the end and no reactive photoreactive functional group at the remaining end (ie, having a non-reactive end).
[3] One of the urethane compounds produced by a urethane reaction between a polyol, a monool containing no photoreactive functional group, a monool containing a photoreactive functional group, and a polyisocyanate. A urethane compound having a reactive photoreactive functional group at the end and no photoreactive functional group at the remaining end (ie, having a non-reactive end).
[4] A urethane compound produced by a urethane reaction between a polyol, a monool containing no photoreactive functional group, and a polyisocyanate, that is, a urethane in which all terminals present in the urethane compound are non-reactive. Compound.
Note that FIG. 3 shows a schematic diagram of the above four types of urethane compounds. Here, reference numeral 10 is a photoreactive functional group terminal. Reference numeral 11 is a photonon-reactive functional group terminal. The curve of reference numeral 12 is a polymer main chain and a side chain.

When the urethane compounds of [1] and [2] are irradiated with light, their plurality of photoreactive functional groups are crosslinked. When the urethane compound of [3] is irradiated with light, one photoreactive functional group undergoes a cross-linking reaction with another urethane compound [1] [2] and the other [3], and the urethane compound of [3] Urethane compounds are configured as side chains of other urethane compounds. When the urethane compound of [4] is irradiated with light, it does not undergo a cross-linking reaction and remains in the composition as a sol component.

The urethane compound having a high degree of cross-linking derived from the above [1] and [2] has the characteristics of improving the cohesive force as an adhesive and increasing the shear mechanical properties (holding force and the like) and heat resistance.
Here, the holding force is the ability of the adhesive to withstand a static load in the shearing direction (sliding direction), and is an index of the creep characteristics of the adhesive. Therefore, it is used as an index of the hardness of the adhesive and the stability with respect to temperature. That is, as the holding force increases, the adhesive becomes harder (the rigidity increases) and the heat resistance (heat resistant temperature) also increases.

In order to increase the holding power, for example, it can be adjusted by increasing the internal energy of the adhesive. Specifically, a method of making the main skeleton rigid by increasing the molecular weight or increasing the degree of cross-linking is used. However, when the holding force is increased, for example, the flexibility of the adhesive is reduced, so that the rough surface followability of the adherend is lowered.
The method for measuring the holding power (heat-resistant holding power) of the pressure-sensitive adhesive can be measured by the method described later.

The urethane compound having a side chain structure derived from the above [3] has a feature that there are few cross-linking points and the flexibility of following an uneven rough surface such as a foam as an adhesive is improved.

The sol component derived from the above [4] improves the adhesiveness of the pressure-sensitive adhesive to the non-adhesive adherend. However, the sol component has a relatively low molecular weight, and if the content is too large, the cohesive force of the pressure-sensitive adhesive is lowered, and the shear mechanical properties (holding power, etc.) of the pressure-sensitive adhesive are lowered. In addition, heat resistance is also reduced.

The amounts of the urethane compounds [1] to [4] contained in the prepolymer have a trade-off relationship with each other in terms of the performance imparted to the pressure-sensitive adhesive, and the ratio is adjusted according to the use as the pressure-sensitive adhesive. be able to. That is, if the cohesive force is high due to the compound of the above [1], the shear mechanical properties and the heat resistance are improved, but it becomes too hard and the adhesiveness derived from the above [3] and the adhesiveness derived from the above [4] are derived. Rough surface followability is reduced. On the other hand, if there are many sol components derived from the above [4] and side chain structures derived from the above [3] (there are few cross-linking points), the adhesiveness and the rough surface followability are improved, but the origin is derived from the above [1]. The cohesive force is reduced and the shear mechanical properties are reduced.

In the urethane prepolymer, the ratio of the equivalent number (a) of the photoreactive functional group bonded to the terminal of the urethane compound and the equivalent number (b) of the photonon-reactive functional group contained in the urethane prepolymer {(( The a) / (b)} is preferably 0.4 to 2.5. This ratio determines the viscoelastic properties of the adhesive {the degree of cross-linking, the concentration (or density) of the side chain structure, and the amount of sol components} when the adhesive is crosslinked by light irradiation. Therefore, it affects the shear mechanical properties, rough surface followability, adhesiveness, and heat resistance of the pressure-sensitive adhesive. When this ratio is less than 0.4, a polymer having many side chain structures is formed, and the sol component is also large. Therefore, although the adhesiveness and the rough surface followability are improved, the shear mechanical properties and the heat resistance tend to be lowered. On the contrary, when this ratio exceeds 2.5, the shear mechanical properties and heat resistance tend to increase, but the adhesiveness and rough surface followability tend to decrease.

The equivalent number (a) of the photoreactive functional group can be calculated from the content of isocyanate groups contained in the urethane prepolymer after the urethane prepolymer synthesis, and the equivalent number (b) of the photonon-reactive functional group is before the synthesis. It can be the equivalent number of monool blended in.
Here, the content of isocyanate groups in the urethane prepolymer can be measured by a known method, and can be measured, for example, in accordance with JIS Z1603-1: 2007 "Polyurethane Raw Material Aromatic Isocyanate Test Method".

The weight average molecular weight of the urethane prepolymer is preferably 2500 to 25000 because it is easy to adjust the cohesive force (shear mechanical property) as the pressure-sensitive adhesive, the adhesiveness, and the rough surface followability within a preferable range. If it is smaller than 2500, the cohesive force is insufficient and the shear mechanical properties as an adhesive are lowered. On the other hand, if it is larger than 25,000, the cohesive force is too strong, and the adhesiveness and the rough surface followability are lowered.
Here, the weight average molecular weight can be measured by a known method. For example, it can be measured by using gelper emission chromatography, using tetrahydrofuran (THF) as an eluent, and detecting the differential refractive index. The weight average molecular weight can be calculated by creating a calibration curve based on the GPC measurement result of polystyrene as a standard sample and using the measurement result of the measurement sample as a polystyrene-equivalent value.

(2.1.1.1) Polypolymer The polyol contained in the raw material of the urethane prepolymer is a compound having two or more hydroxyl groups in one molecule, and is not particularly limited as long as the effect of the present invention is not impaired.
Examples of the polyol used in the present invention include polyester polyol, polycarbonate polyol, polyether polyol, polyester ether polyol and the like. The polyol may be used alone or in combination of two or more.
Since the polyol forms the skeleton of the urethane prepolymer, the influence of its structure (carbon number of the skeleton, side chain structure, etc.) on the cohesive force (shear mechanical properties), adhesiveness, and rough surface followability is taken into consideration. , Can be selected.

Examples of the polyester polyol include aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid and azelaic acid, and aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid. Acids such as hexahydrophthalic acid, hexahydroterephthalic acid and hexahydroisophthalic acid, or their acid esters or acid anhydrides, and ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,3 -Butandiol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9 Examples thereof include polyester polyols such as polypropylene glycol obtained by dehydration condensation reaction with −nonandiol and the like, or polylactone diols obtained by ring-open polymerization of lactone monomers such as ε-caprolactone and methylvalerolactone. ..

Examples of the polycarbonate polyol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexane. At least one of polyhydric alcohols such as diol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, and diethylene glycol, and diethylene carbonate, dimethyl carbonate, diethyl. Examples thereof include those obtained by reacting with carbonate and the like.

Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol and the like obtained by polymerizing cyclic ethers such as ethylene oxide, propylene oxide and tetrahydrofuran, and copolyethers thereof. It can also be obtained by polymerizing the above cyclic ether using a polyhydric alcohol such as glycerin or trimethylolethane.

Examples of the polyester ether polyol include aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid and azelaic acid, and aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid. Dicarboxylic acids such as hexahydrophthalic acid, hexahydroterephthalic acid and hexahydroisophthalic acid, or acid esters or acid anhydrides thereof, and glycols such as diethylene glycol or propylene oxide adduct, or mixtures thereof. Examples thereof are those obtained by a dehydration condensation reaction.

(2.1.1.2) Polyisocyanate Polyisocyanate is a compound having two or more isocyanate groups in one molecule, and is not particularly limited as long as it is usually used as a raw material for urethane prepolymers. .. For example, as the bifunctional polyisocyanate, 2,4-toluene diisocyanate (2,4-TDI), 2,6-toluene diisocyanate (2,6-TDI), m-phenylenediisocinate, p-phenylenediisocyanate, etc. 4,4'-Diphenylmethane diisocyanate (4,4'-MDI), 2,4'-diphenylmethane diocyanate (2,4'-MDI), 2,2'-diphenylmethane diisocyanate (2,2'-MDI), hydrogen Added MDI, xylylene diisocyanate, 3,3'-dimethyl-4,4'-biphenylenediisonate, 3,3'-dimethoxy-4,4'-biphenylenediisocyanate, polymethylenepolyphenylpolyisocyanate, 1,5- Aromatic ones such as naphthalenediocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, tetramethylxylene diisocyanate (TMXDI), cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate. , Alicyclic type such as methylcyclohexanediisocyanate, alkylene type such as butane-1,4-diisocyanate, hexamethylenediisocyanate, isopropylene diisocyanate, methylenediisocyanate, lysinediisocyanate, etc. -Methylbenzol-2,4,6-triisocyanate, 1,3,5-trimethylbenzol-2,4,6-triisocyanate, biphenyl-2,4,4'-triisocyanate, diphenylmethane-2,4,4 '-Triisocyanate, methyldiphenylmethane-4,6,4'-triisocyanate, 4,4'-dimethyldiphenylmethane-2,2', 5,5'tetraisocyanate, triphenylmethane-4,4', 4 "- Triisocyanate, polypeptide MDI, lysine ester triisocyanate, 1,3,6-hexamethylene triisocyanate, 1,6,11-undecantryisocyanate, bicycloheptane triisocyanate, 1,8-diisocyanatomethyloctane, etc. and their modifications Examples include bodies and derivatives.
The polyisocyanate exists as a sol component in the pressure-sensitive adhesive of the present invention or as a part of the skeleton of the urethane polymer. Therefore, the carbon number, straight chain, and side chain structure of the polyisocyanate can be selected in consideration of the influence on the cohesive force (shear mechanical property), adhesiveness, and rough surface followability of the pressure-sensitive adhesive according to the present invention. it can.

(2.1.1.3) Monool without Photoreactive Functional Group Monool is a compound having one hydroxyl group in one molecule, and the monool does not contain a photoreactive functional group. It means that the oar is a monool formed only of photonon-reactive functional groups. The monool is not particularly limited as long as it can be bonded to a polyisocyanate group. For example, linear, branched or cyclic monohydric alcohols (methanol, ethanol, propanol, butanol, isobutyl alcohol, tert-butyl alcohol, pentanol, isopentyl alcohol, neopentyl alcohol, hexanol, 2-methyl-1-pentanol). , Octanol, 2-ethyl-1-hexanol, 3,5,5-trimethyl-1-hexanol, decanol, undecanol, 1-dodecanol, isooctadecanol, octadecenol, docosanol, 14-methylhexadecanol, cyclohexanol, Methylcyclohexanol, 2-ethylhexyl glycol, etc.) and the like. In addition, glycol ethers, for example, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether and the like can be mentioned.

Here, the photoreactive functional group is a functional group that can be crosslinked by irradiation with X-ray, electron beam, ultraviolet rays, visible light or the like, that is, a functional group having multiple bonds, for example, an alkenyl group or an alkynyl group. Examples thereof include a vinyl group, an acrylic group, a methacrylate group and an allyl group. The monool does not contain these photoreactive functional groups.

Since the monool does not contain a photoreactive functional group, it does not participate in the cross-linking reaction when irradiated with light, and exists as a sol component in the pressure-sensitive adhesive layer of the present invention or as a side chain of a urethane polymer. Therefore, the carbon number, straight chain, and side chain structure of the monool can be selected in consideration of the influence on the cohesive force (shear mechanical property), adhesiveness, and rough surface followability of the pressure-sensitive adhesive according to the present invention. it can.

(2.1.1.4) Monool Containing Photoreactive Functional Group Monool is a compound having one hydroxyl group in one molecule, and monool is said to contain a photoreactive functional group. , A monool containing at least one photoreactive functional group. The monool is not particularly limited as long as it can be bonded to a polyisocyanate group. For example, monools having an allyl ether group such as allyl ether glycol and hydroxyethyl allyl ether; monools having a vinyl ether group such as 2-hydroxyethyl vinyl ether, diethylene glycol monovinyl ether and 4-hydroxybutyl vinyl ether; hydroxyethyl acrylate and hydroxypropyl. Examples thereof include monool having a (meth) acrylic group such as acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, and 2-hydroxypropyl methacrylate.

Here, the photoreactive functional group is a functional group that can be crosslinked by irradiation with X-ray, electron beam, ultraviolet rays, visible light or the like, that is, a functional group having multiple bonds, for example, an alkenyl group or an alkynyl group. Examples thereof include a vinyl group, an acrylic group, a methacrylate group and an allyl group. When the monool contains a plurality of photoreactive functional groups, the plurality of photoreactive functional groups can be mixed and used.

Since the monool contains a photoreactive functional group, it participates in a cross-linking reaction when irradiated with light, and exists as a main skeleton or a side chain of the urethane polymer in the pressure-sensitive adhesive of the present invention. Therefore, the carbon number, straight chain, and side chain structure of the monool are considered to affect the cohesive force (shear mechanical property), adhesiveness, and rough surface followability of the first pressure-sensitive adhesive layer 5 according to the present invention. You can choose.

(2.1.1.5) Catalyst In the synthesis of the urethane prepolymer, a reaction catalyst may be added in order to accelerate the reaction or increase the reaction rate. Here, the reaction catalyst is not particularly limited, and examples thereof include known catalysts such as tin-based catalysts, lead-based catalysts, other metal catalysts, amine-based catalysts, other acidic catalysts, and basic catalysts. Be done. One or more of these catalysts can be used.

(2.1.2) Polythiol Polythiol is a compound having two or more thiol groups in one molecule, and is not particularly limited as long as it does not inhibit the effect of the present invention.
Examples of the polythiol that undergoes an en-thiol reaction with the urethane prepolymer obtained by the above compound include an ester of a mercaptocarboxylic acid and a polyhydric alcohol, an aliphatic polythiol, and an aromatic polythiol. Examples of the aliphatic polythiol and the aromatic polythiol include ethanedithiol, propanedithiol, hexamethylenedithiol, decamethylenedithiol, tolylen-2,4-dithiol, and xylenedithiol.

In the ester of mercaptocarboxylic acid and polyhydric alcohol, mercaptocarboxylic acid includes thioglycolic acid, mercaptopropionic acid and the like, and polyhydric alcohols include ethylene glycol, propylene glycol, 1,4-butanediol, 1 , 6-Hexanediol, glycerin, trimethylolpropane, pentaerythritol, sorbitol and the like. Among these, esters of mercaptocarboxylic acid and polyhydric alcohol are preferable in terms of low odor, and specifically, for example, trimethylolpropane tris (3-mercaptopropionate) and pentaerythritol tetrakis (3). -Mercaptopropionate), tetraethylene glycol bis (3-mercaptopropionate), dipentaerythritol hexa (3-mercaptopropionate). It is possible to use one or a combination of two or more of these various polythiols as a raw material for the en-thiol reaction with the urethane prepolymer.

By mixing polythiol with the urethane prepolymer and subjecting them to a polymerization reaction (en-thiol reaction), an en-thiol-based pressure-sensitive adhesive composition having high flexibility can be obtained. Here, the polymerization reaction may be a photopolymerization reaction or a thermal polymerization reaction. In the case of the photopolymerization reaction, after mixing the above-mentioned polythiol and the urethane prepolymer, light (ultraviolet rays, etc.) By irradiating with, the en-thiol reaction is promoted. The reaction mechanism of the thermal polymerization reaction is the same as that of the photopolymerization reaction, and the only difference is whether the radicals are generated by light or heat. Here, since the photopolymerization reaction proceeds faster than the thermal polymerization reaction, it is preferable to use the photopolymerization reaction in the method for producing the pressure-sensitive adhesive composition according to the present invention.

Further, by using a polythiol having a number of functional groups (thiol groups) of 2 (bifunctional thiol) and a polythiol having a functional group (thiol group) of 2 or more (thiol having trifunctionality or higher) in combination, an enzyme having even higher flexibility -It becomes possible to obtain a thiol-based adhesive composition. Specifically, the average number of functional groups of thiols that react with the urethane prepolymer, that is, the average number of functional groups of thiols of polythiol having two thiol groups and polythiol having three or more thiol groups is set to 2. When the content is 5.5 or more, an en-thiol-based pressure-sensitive adhesive composition having high flexibility can be obtained.

(2.1.3) Compound (resin) having a plurality of photoreactive functional groups
The compound (resin) having a plurality of photoreactive functional groups is a compound having two or more photoreactive functional groups in one molecule, and more preferably three or more. The two or more photoreactive functional groups may all be the same functional group or may contain different functional groups. These photoreactive functional groups are crosslinked with urethane prepolymer and / or polythiol by a crosslinking reaction by light irradiation.

The urethane prepolymer according to the present invention contains a large amount of sol components and further contains a large amount of side chain structures. In this case, the cohesive force as an adhesive after the crosslinking reaction is low, and therefore the shear mechanical properties are low. In the present invention, the degree of cross-linking of the pressure-sensitive adhesive can be increased by adding the compound (resin) to increase the cross-linking points, and the pressure-sensitive adhesive can be made suitable as a pressure-sensitive adhesive. Here, in the present specification, the compound (resin) having a plurality of photoreactive functional groups includes a monomer, a multimer, and a polymer.

The weight average molecular weight of the compound (resin) having a plurality of photoreactive functional groups is not particularly limited, but is preferably smaller than the weight average molecular weight of the urethane prepolymer. As the molecular weight decreases, the concentration of the photoreactive functional group with respect to the molecular weight of the compound (resin) having a plurality of photoreactive functional groups increases, and the concentration of the cross-linking point in the molecular structure as a pressure-sensitive adhesive can be increased. it can. Therefore, the smaller the molecular weight of the compound (resin) having a plurality of photoreactive functional groups, the more rigid the structure after cross-linking can be, and the more suitable the shear mechanical properties as an adhesive are. Can be. From this point of view, a monomer is preferable, and an acrylic monomer is more preferable.

Here, the photoreactive functional group is a functional group that can be crosslinked by irradiation with X-ray, electron beam, ultraviolet rays, visible light or the like, that is, a functional group having multiple bonds, for example, an alkenyl group or an alkynyl group. Examples thereof include a vinyl group, an acrylic group, a methacrylate group and an allyl group.

The compound (resin) having a plurality of photoreactive functional groups is not particularly limited as long as it has a plurality of photoreactive functional groups. Examples thereof include acrylic resin, urethane resin, ethylene-vinyl acetate resin, vinyl chloride resin, vinyl acetate resin, styrene resin, vinyl alcohol resin, vinyl pyrrolidone resin, vinyl butyral resin, methacrylate resin and allyl ether resin. Further, a plurality of the resins can be mixed and used.

(2.1.4) Adhesive-imparting agent The adhesive-imparting agent is not particularly limited as long as it exhibits adhesiveness by a plasticizing action in a polymer material, and is, for example, a rosin-based resin or a terpene-based resin. , Alicyclic petroleum resin, alicyclic petroleum resin, aromatic petroleum resin, chromalon inden resin, styrene resin, phenol resin, xylene resin and the like can be added. The blending amount of the tackifier can be 5 to 30 parts by mass with respect to 100 parts by mass of the urethane prepolymer.

(2.1.5) Other Additives As other additives, in order to effectively carry out the polymerization reaction between the urethane prepolymer and the compound (resin) having a plurality of photoreactive functional groups and the thiol group. The pressure-sensitive adhesive composition of the present invention may contain a photopolymerization initiator. Examples of the photopolymerization initiator used in the case of the photopolymerization reaction include acetophenone-based, benzophenone-based, and thioxanthone-based compounds. Examples of the acetophenone system include 2,2-dimethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 4- (1-t-butyldioxy-1-methylethyl) acetophenone, and 2-methyl-1- [4-]. (Methylthio) phenyl] -2-morpholino-propane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, diethoxyacetophenone, 2-hydroxy-2-methyl- 1-Phenylpropan-1-one, benzyldimethylketal, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexylphenylketone, 2-hydroxy-2-methyl-1 -[4- (1-Methylvinyl) phenyl] propanone oligomer and the like can be mentioned.

Examples of the benzophenone system include 4- (1-t-butyldioxy-1-methylethyl) benzophenone, 3,3', 4,4'-tetrakis (t-butyldioxycarbonyl) benzophenone, and methyl o-benzoyl benzoate. , 4-Phenylbenzophenone, 4-benzoyl-4'-methyl-diphenylsulfide, 3,3', 4,4'-tetra (t-butylperoxylcarbonyl) benzophenone, 2,4,6-trimethylbenzophenone, 4- Examples thereof include benzoyl-N, N-dimethyl-N- [2- (1-oxo-2-propenyloxy) ethyl] benzenemethanamineium bromide, and (4-benzoylbenzyl) trimethylammonium chloride. Examples of the thioxanthone system include 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, and 2,4-dichloro. Examples thereof include thioxanthone, 1-chloro-4-propoxythioxanthone, 2- (3-dimethylamino-2-hydroxy) -3,4-dimethyl-9H-thioxanthone-9-omethanechloride.

Further, the raw material composition of the present invention may contain various additives in addition to the above-mentioned components, if necessary, as long as the effects of the present invention are not impaired. Examples of the additive include a filler, a plasticizer, a pigment, a dye, an antioxidant, an antioxidant, an antistatic agent, a flame retardant, an antibacterial agent, a light stabilizer, a stabilizer, a dispersant and the like.

2. 2. Production of Sealing Material 1 (1) Formulation of Raw Material for Adhesive The preferable composition of each raw material will be described in detail below.
The compounding amount of the polyol in the synthesis of the urethane prepolymer is 100 parts by mass.
The monool is the equivalent number (a) of the photoreactive functional group bonded to the terminal of the urethane compound and the equivalent number (b) of the photonon-reactive functional group contained in the urethane prepolymer mixture described above. It can be blended so that the ratio {(a) / (b)} is 0.4 to 2.5.

The polyisocyanate can be blended so that the hydroxyl group equivalent is calculated from the blending amount of the polyol and monool so that all the hydroxyl groups fully react with the isocyanate group.

The compound (resin) having a plurality of photoreactive functional groups has the number of double bond equivalents of the photoreactive functional groups contained in the urethane prepolymer and the photoreaction contained in the compound (resin) per unit mass. When the total value with the double bond equivalent number of the sex functional group is 0.1 to 0.5 mol / kg and the compounding amount is 100 parts by mass of the urethane prepolymer. , 0.3 parts by mass or more can be blended. Here, when the photoreactive functional group contains a triple bond, the number of triple bonds is doubled and added. When this blending amount is less than 0.1 mol / kg, the degree of cross-linking due to the en-thiol reaction is low, and the shear mechanical properties and heat resistance of the pressure-sensitive adhesive are lowered. Further, when this ratio exceeds 0.5 mol / kg, the adhesiveness as an adhesive and the rough surface followability are lowered. Further, when the compounding amount of the compound (resin) is less than 0.3 parts by mass, the degree of cross-linking becomes small, and the shear mechanical properties and heat resistance deteriorate. The upper limit of the blending amount of the compound (resin) is not particularly limited, but is usually 6.0 parts by mass.

The polythiol is blended so that the thiol-ene (thiol group / double bond) ratio is 0.7 to 2.5 with respect to the double bond equivalent number of the photoreactive functional group. If this ratio is less than 0.7, the degree of cross-linking is small, so the shear mechanical properties and heat resistance are lowered, and if this ratio is larger than 2.5, the degree of cross-linking is too large. Therefore, the adhesiveness and the rough surface followability are reduced.
In addition, this requirement is a double of the equivalent number (c) of thiol groups contained in polythiol and the total photoreactive functional groups contained in the urethane prepolymer and the compound (resin) having a plurality of photoreactive functional groups. It is synonymous with the ratio {(c) / (d)} to the equivalent number (d) of the bond being 0.7 to 2.5.
The thiol-ene (double bond) ratio can also be indexed as a thiol index. The thiol index is a value obtained by multiplying the ratio of the number of moles of thiol groups in the thiol compound to the number of moles of double bond groups by 100, and is 70 to 250.

(2) Method for producing urethane prepolymer The method for producing the urethane prepolymer is not particularly limited, and a known method can be used. A suitable example thereof will be described below.
Add the amount of polyisocyanate to the container and stir in a nitrogen atmosphere. The polyol is dropped here. Here, in order to promote the reaction, a catalyst can be added as needed. The amount of the catalyst added is not particularly limited, but can be, for example, 0.01 to 5 parts by mass with respect to 100 parts by mass of polyisocyanate.
Stir for a predetermined time to complete the reaction. Here, a part of the reaction product is extracted, the isocyanate group content is measured, and it is confirmed that the reaction product is within the desired range. After confirmation, monool containing a photoreactive functional group and monool not containing a photoreactive functional group are added and reacted for a predetermined time to obtain a prepolymer.

(3) Method for Producing Raw Material Composition for Adhesive The method for producing the raw material composition for a pressure-sensitive adhesive is not particularly limited, and a known method can be used. An example thereof will be described below.
While stirring the urethane prepolymer obtained as described above, a predetermined amount of a resin having a plurality of photoreactive groups, polythiol, and a tackifier is added to prepare a raw material composition.

(4) Manufacturing Method of Sealing Material 1 The manufacturing method of the sealing material 1 is not particularly limited, and a known method can be used. An example thereof will be described below.
The raw material composition is coated on a paper pattern (arbitrary constituent requirement) to a predetermined thickness. Next, the coated raw material composition is cured by light irradiation to form the first pressure-sensitive adhesive layer 5.
The sealing material 1 shown in FIG. 1 can be manufactured by further adhering the base material 3 to the pressure-sensitive adhesive surface on the first pressure-sensitive adhesive layer 5 formed on the release paper.
Further, the sealing material 1 can also be manufactured as follows. The raw material composition is applied onto the base material 3 to a predetermined thickness. Next, the coated raw material composition is cured by light irradiation to form the first pressure-sensitive adhesive layer 5, and the sealing material 1 shown in FIG. 1 can be produced. The first pressure-sensitive adhesive layer 5 formed on the base material 3 may be further bonded with a release paper (arbitrary constituent requirement) on the pressure-sensitive adhesive surface.

The sealing material 1 shown in FIG. 2 can be manufactured, for example, as follows.
The raw material composition is applied to both sides of the film-like support 9 to a predetermined thickness. Next, the coated raw material composition is cured by light irradiation to become a first pressure-sensitive adhesive layer 5 and a second pressure-sensitive adhesive layer 7. In this way, the double-sided tape 31 in which the first pressure-sensitive adhesive layer 5 and the second pressure-sensitive adhesive layer 7 are formed on both sides of the film-like support 9 is manufactured. Then, by adhering the base material 3 to the second pressure-sensitive adhesive layer 7 of the double-sided tape 31, the sealing material 1 shown in FIG. 2 can be manufactured. The first pressure-sensitive adhesive layer 5 may be further bonded with a paper pattern (arbitrary constituent requirement) on the pressure-sensitive adhesive surface.

The method of coating the raw material composition is not particularly limited, and a known method can be used. Examples of the coating method include a comma coater, a die coater, and a gravure coater. A die coater capable of adjusting the temperature at the time of coating and adjusting the coating viscosity of the raw material composition is preferable.

The release paper is composed of a paper as a base material and a release layer formed on the surface thereof, and is easily peeled from an adhesive material (adhesive sealing material). The base material of the release paper is not limited to paper, and a known resin film can be used. For example, a PET film, an OPP film, or the like can be used. The thickness of the base material is not particularly limited, and can be, for example, 10 μm to 200 μm.
Further, the release layer can be formed by using a known release agent. For example, a silicone compound such as dimethylsiloxane can be used.

The light irradiation is carried out by irradiating light at a specific wavelength with which the photoreactive functional group reacts or a specific wavelength with which the added photopolymerization initiator acts. The amount of light irradiation can be set depending on the composition and thickness of the raw material composition, the type and amount of the photopolymerization initiator added, and the like, for example, 600 to 1800 mJ / cm ^2, and Irgacure 1173 (manufactured by BASF). ) Is used as a photopolymerization initiator, it can be cured by irradiating it with light having a wavelength of 365 nm.

3. 3. Uses of the sealing material 1 The use of the sealing material 1 is not particularly limited. The sealing material 1 can be suitably used as a sealing material for concrete. The sealing material 1 can be suitably used as, for example, a sealing material for construction, a sealing material for civil engineering, a sealing material 1 between precast PC floor slabs, and a sealing material 1 for synthetic plate plates.

4. Effect of the sealing material 1 of the present embodiment The sealing material 1 of the present embodiment uses a urethane-based first adhesive layer 5 to increase the adhesive force to concrete without thickening the first adhesive layer 5. Can be secured.
Further, the sealing material 1 of the present embodiment easily follows the unevenness of concrete, and sufficient sealing property is ensured.

Examples will be shown below, and the present invention will be described in more detail. However, the present invention is not limited to this embodiment, and can be carried out in various embodiments with various modifications and improvements based on the knowledge of those skilled in the art.
1. 1. Preparation of Adhesive (1) Raw Materials The following raw materials were weighed and blended according to Tables 1 to 3.
-Polypropylene a: Polypropylene glycol Molecular weight 3000
-Polypropylene b: Polypropylene glycol Molecular weight 200
-Monool without photoreactive functional groups: Lauryl alcohol-Monool with photoreactive functional groups: Hydroxyethyl acrylate-Polyisocyanate: Tolylene diisocyanate (2,4-tolylene diisocyanate: 80%, 2,6 − Tolylene diisocyanate: 20%)
-Compound having a plurality of photoreactive functional groups (resin): Trimethylolpropane triacrylate (TMPTA: number of photoreactive functional groups 3)
・ Adhesive-imparting agent: Super Ester-A100 (manufactured by Arakawa Chemical Industry Co., Ltd.)
-Polythiol: Trimethylolpropane Tris (3-mercaptopropionate)
(TMMP: molecular weight: 399, average cardinal number 3)
Thiol index = 100
SH functional cardinal number = 3.0
-Initiator: Irgacure 1173 (manufactured by BASF)

(Various properties)
-Table 2 shows the properties of the urethane prepolymer.
-Total double bond amount per unit mass (mol / kg) representing the double bond amount of all photoreactive functional groups contained in the urethane prepolymer and the compound (resin) having a plurality of photoreactive functional groups. Was 0.252.

(2) Preparation of urethane prepolymer The blending amount of the raw material is weighed according to Table 1. A mixture of polyisocyanate was placed in a separate flask, and the mixture was stirred under a nitrogen atmosphere. The polyols a and b are added dropwise thereto. After completion of the dropping, 0.3 g of a catalyst (dibutyltin dilaurate) was added. After reacting for 3 hours, a part was sampled and the isocyanate group content was measured, and it was confirmed that the reaction was within the range for each of the following prepolymers.
The isocyanate content was measured according to a method based on JIS Z1603-1: 2007 (polyurethane raw material aromatic isocyanate test method). Next, monool was added dropwise and reacted for 2 hours. After the reaction, sample ring was performed to confirm that the isocyanate group content was 0.05% or less. When the isocyanate group content was 0.05% or less, the reaction was completed and the product was a urethane prepolymer.

(3) Method for Producing Raw Material Composition of Adhesive The raw material composition of the pressure-sensitive adhesive is a compound (resin) having a plurality of photoreactive functional groups and polythiol while stirring the weighed urethane prepolymer according to Table 3. , A predetermined amount of the tackifier was added to prepare a raw material composition.

2. 2. Preparation of Double-sided Tape 31 for Sealing Material 1 The double-sided tape 31 used for the sealing material 1 shown in FIG. 2 was produced. As shown in FIG. 2, the double-sided tape 31 has a structure in which the first pressure-sensitive adhesive layer 5 and the second pressure-sensitive adhesive layer 7 are formed on both sides of the film-like support 9.
(1) Example 1
A pressure-sensitive adhesive layer (the first pressure-sensitive adhesive layer 5 and the first pressure-sensitive adhesive layer 5 in FIG. 2) was used on both sides of the polyurethane foam (film-like support 9) shown in Table 4 using the raw material composition described in “1. The second pressure-sensitive adhesive layer 7) was formed to prepare a double-sided tape 31.
The pressure-sensitive adhesive layer was cured by light irradiation (wavelength: 365 nm, irradiation amount 800 mJ / cm ² ).
(2) Example 2
A pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer 5 and second pressure-sensitive adhesive) was used on both sides of the Japanese paper (film-like support 9) shown in Table 4 using the raw material composition described in "1. Preparation of adhesive material" above. The layer 7) was formed to prepare a double-sided tape 31.
The pressure-sensitive adhesive layer was cured by light irradiation (wavelength: 365 nm, irradiation amount 800 mJ / cm ² ).
(3) Comparative Example 1
A double-sided tape (manufactured by Ebisu Kasei Co., Ltd.) using an acrylic adhesive was used.
(4) Comparative Example 2
A double-sided tape using an acrylic adhesive (manufactured by 3M Ltd., model number: DCX1018) was used.
(5) Comparative Example 3
A double-sided tape using an acrylic adhesive (manufactured by 3M Ltd., model number: SKB-20) was used.
(6) Comparative Example 4
A double-sided tape using a rubber-based adhesive (manufactured by 3M Ltd., model number: PCD-50) was used.

2. 2. Evaluation method of double-sided tape 31 (1) Measurement of peel strength against concrete (see FIG. 4)
Double-sided tapes 31 (test samples) of Examples 1 and 2 and Comparative Examples 1 to 4 were applied to concrete 37 (adhesion) using a rubber roller having a weight of 2 kg, respectively, at 5 mm / sec. It was reciprocated once at the speed of 1 and pasted together. Then, the one left to stand for 30 minutes was used for the measurement.
The peel strength against foam was measured by performing a 180-degree peel test using a material testing machine (manufactured by A & D Co., Ltd .: Tencilon RAC-1150A). The measurement was carried out by fixing the portion 10 mm from the end of the double-sided tape 31 and the concrete 37 to the chuck portion 33 of the material testing machine and peeling it off at a tensile speed (crosshead speed) of 200 mm / min. The tensile strength at the time of peeling was defined as the peel strength. Table 4 shows the measurement results of each Example and Comparative Example.
Table 4 shows the results of evaluation of each of a plurality of types of double-sided tapes 31 having different widths.

(2) Heat resistance holding power measurement (see Fig. 5)
The heat-resistant holding power (mm) of the double-sided tape 31 under a high temperature condition was measured. Specifically, as shown in FIG. 5, the SUS 304 plate 41 was held so as to extend in the vertical direction. The first adhesive layer of the double-sided tape 31 was attached to the lower end of the SUS 304 plate 41 so that the adhesive area was 25 mm × 25 mm. The double-sided tape 31 and the SUS 304 plate 41 were bonded together using a crimping roller. The crimping conditions were such that the speed of the crimping roller was 5 mm / sec and the crimping roller was reciprocated once.
A PET film (not shown) having a thickness of 25 μm is attached to the surface of the double-sided tape 31 opposite to the surface on which the first adhesive layer is attached to the SUS 304 plate 41. Further, 30 minutes after the double-sided tape 31 was attached to the SUS 304 plate 41, a weight 43 of 500 g was hung from the lower end of the double-sided tape 31 and left for 60 minutes in an environment of 80 ° C. Then, the amount of deviation (mm) of the double-sided tape 31 after being left for 60 minutes was measured, and the amount of deviation was defined as the heat-resistant holding power (mm).

(3) Tack (initial adhesive strength)
The second adhesive layer 7 was attached to the aluminum plate with the first adhesive layer 5 of the double-sided tape 31 facing upward and the second adhesive layer 7 facing downward. The aluminum plate was fixed to the chuck part on the lower side of the material tester. A weight (size: bottom area 1 cm ² , weight 10 g) is adhered on the first adhesive layer 5 only by its own weight, and 3 seconds after the adhesion, the upper part of the weight is fixed to the upper chuck portion to form the first adhesive layer 5. The initial adhesive force required for peeling the pressure-sensitive adhesive layer 5 and the weight was measured. The surface of the weight was wiped clean with acetone and then adhered to the first pressure-sensitive adhesive layer 5. The measurement conditions were a tensile speed of 200 mm / min.

3. 3. Evaluation result of double-sided tape 31 (1) Result of measurement of peel strength against concrete The results are also shown in Table 4. In Table 4, "-" means that the measurement was not performed.
Examining the evaluation results of the double-sided tape 31 having a width of 25 mm and a width of 30 mm, it was confirmed that Examples 1 and 2 had higher peel strength against concrete than any of the comparative examples.

(2) Results of heat resistance holding power measurement In Comparative Example 4, the heat resistance holding power was low. It was confirmed that Examples 1 and 2 have the same heat-resistant holding power as Comparative Examples 1 to 3, and are highly practical.

(3) Tack (Initial Adhesive Strength) Measurement Results It was confirmed that Examples 1 and 2 had a tack (initial adhesive strength) equal to or higher than that of Comparative Examples 1 to 4, and were highly practical.

4. Adhesive strength of the sealing material 1 to concrete The physical properties of the double-sided tape 31 were evaluated by various measurements as described above. These physical properties mainly evaluate the physical properties of the first pressure-sensitive adhesive layer 5 of the double-sided tape 31.
By the way, the sealing material 1 of FIG. 2 is configured by attaching a double-sided tape 31 (double-sided tape composed of a film-like support 9, a first adhesive layer 5, and a second adhesive layer 7) to a base material 3. ing. The sealing material 1 is used by attaching the first pressure-sensitive adhesive layer 5 to an adherend (adhesive body). As described above, even in the sealing material 1, the first adhesive layer 5 is used for adhesion (adhesion) to the adherend (adhesive body). Therefore, in the sealing material 1, the first of the double-sided tape 31 is also used. According to the above evaluation result in which the physical properties of the pressure-sensitive adhesive layer 5 are mainly evaluated, a result that the adhesive strength to concrete is high can be obtained.

The present invention is not limited to the embodiments detailed above, and various modifications or modifications can be made within the scope of the claims of the present invention.

1 ... Sealing material 2 ... Adhesive material 3 ... Base material 5 ... Adhesive layer (first adhesive layer)
7 ... Second adhesive layer 9 ... Film-like support 10 ... Photoreactive functional group terminal 11 ... Photoreactive functional group terminal 12 ... Polymer main chain and side chain 31 ... Double-sided tape 33 ... Chuck of material testing machine Part 37 ... Concrete 41 ... SUS 304 Plate 43 ... Weight

Claims (7)

A base material made of foam and
A sealing material comprising an adhesive layer provided on at least one side of the base material.
The pressure-sensitive adhesive layer comprises a pressure-sensitive adhesive made from a raw material composition containing a urethane prepolymer, a polythiol, a compound containing a plurality of photoreactive functional groups, and a pressure-sensitive adhesive.
The urethane prepolymer contains a polyol, a polyisocyanate, a monool containing no photoreactive functional group, and a monool containing a photoreactive functional group as raw materials.
A sealing material characterized by that. The ratio {(c) / of the equivalent number (c) of the thiol group contained in the polythiol to the double bond equivalent number (d) of the total photoreactive functional group contained in the urethane prepolymer and the compound. The sealing material according to claim 1, wherein (d)} is 0.7 to 2.5. The ratio {(a) / (b)} of the equivalent number (a) of the photoreactive functional group present at the end of the urethane prepolymer to the equivalent number (b) of the photonon-reactive functional group is 0.4 to 2.5
The total double bond amount (mol / kg) per unit mass representing the double bond amount of all the photoreactive functional groups contained in the urethane prepolymer and the compound is 0.1 to 0.5. ,
The sealing material according to claim 1 or 2, wherein the compounding amount of the compound is 0.3 parts by mass or more with respect to 100 parts by mass of the urethane prepolymer. The sealing material according to any one of claims 1 to 3, wherein the blending amount of the tackifier is 5 to 30 parts by mass with respect to 100 parts by mass of the urethane prepolymer. The sealing material according to any one of claims 1 to 4, wherein the foam has a skin layer on the surface. The foam has a density of 20 to 200 kg / m ³ .
The sealing material according to any one of claims 1 to 5, wherein the 25% compressive hardness is 30 to 350 kPa. The present invention according to any one of claims 1 to 6, wherein a second pressure-sensitive adhesive layer and a support are arranged in this order from the base material side between the base material and the pressure-sensitive adhesive layer. The sealing material described.

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