JP7409217B2 - Adhesive set, structure and manufacturing method thereof - Google Patents

Description

TECHNICAL FIELD The present disclosure relates to adhesive sets and structures and methods of manufacturing the same.

Steel plates are generally used for interior and exterior parts such as automobile bodies, front doors, rear doors, back doors, front bumpers, rear bumpers, locker moldings, etc., but in order to meet recent demands for improved fuel efficiency, there is a need for lighter weight. It is being For this reason, plastic materials such as polypropylene are increasingly being used as interior and exterior parts of automobiles instead of steel plates. Note that since plastic materials such as polypropylene have lower strength than steel plates, it is common to add talc, glass filler, etc. to improve the strength.

Urethane adhesive compositions have been proposed as adhesives between automobile parts made of plastics such as polypropylene. The urethane adhesive composition uses a one-component curing adhesive called a moisture curing type that cures due to moisture in the air, and an adhesive set consisting of a main agent and a curing agent. Two-component curing adhesives that are mixed with a curing agent are known. In a two-component curable urethane adhesive composition, a crosslinking reaction between the isocyanate group (NCO group) component contained in the base agent and the hydroxy group (OH group) contained in the curing agent progresses and cures. Among these, from the viewpoint of workability in the adhesion process, it is possible to secure a sufficient pot life (pot life, the time until the paint starts to harden due to chemical reaction, etc. in multi-component paints) and to enable quick curing. There is a tendency to prefer two-component curing adhesives.

In general, polypropylene base materials have low surface polarity and are difficult to adhere to, so in order to facilitate adhesion, a surface treatment is performed to introduce polar groups into the surface of the base material. Examples of the surface treatment include corona treatment, flame treatment, plasma treatment, and the like. Furthermore, since it is difficult to directly apply a urethane adhesive composition to bond surface-treated polypropylene base materials, each polypropylene base material is pretreated with a primer before applying the urethane adhesive composition. It is common to apply a composition. However, in recent years, from the viewpoint of process simplification and work environment improvement, urethane adhesive compositions have been required to have improved adhesion without primer treatment (i.e., non-primer adhesion). .

For example, Patent Document 1 discloses a two-component curable urethane adhesive composition in which a base agent containing a urethane prepolymer and an isocyanate silane compound and a curing agent containing polybutadiene diol are mixed during operation. There is.

Japanese Patent Application Publication No. 2014-077094

However, conventional two-part curable urethane adhesive compositions do not have sufficient non-primer adhesive properties, and there is still room for improvement.

Therefore, the main object of the present disclosure is to provide an adhesive set that allows the preparation of an adhesive composition that exhibits excellent non-primer adhesion.

One aspect of the present disclosure relates to adhesive sets. The adhesive set includes a base agent and a curing agent. The main ingredient contains a urethane prepolymer and a silane coupling agent having an alicyclic epoxy group. The curing agent contains a polyol. Adhesive compositions prepared using such adhesive sets can exhibit excellent non-primer adhesion.

Another aspect of the present disclosure relates to a structure. The structure includes a first base material, a second base material, and an adhesive layer that adheres the first base material and the second base material to each other. The adhesive layer contains a cured product of an adhesive composition containing a main agent and a curing agent in the adhesive set described above.

Another aspect of the present disclosure relates to a method of manufacturing a structure. The method for manufacturing the structure includes a step of bonding a first base material and a second base material together via an adhesive composition containing a base agent and a curing agent.

According to the present disclosure, an adhesive set is provided that makes it possible to prepare an adhesive composition that exhibits excellent non-primer adhesion. Adhesive compositions prepared from the adhesive set of one aspect of the present disclosure can also exhibit excellent heat resistance and hot water resistance. Further, according to the present disclosure, a structure using such an adhesive set and a manufacturing method thereof are provided.

Embodiments of the present disclosure will be described below. However, the present disclosure is not limited to the following embodiments. Note that in this specification, a numerical range indicated using "~" indicates a range that includes the numerical values written before and after "~" as the minimum value and maximum value, respectively. Furthermore, in the numerical ranges described stepwise in this specification, the upper limit or lower limit of the numerical range of one step may be replaced with the upper limit or lower limit of the numerical range of another step. Further, in the numerical ranges described in this specification, the upper limit or lower limit of the numerical range may be replaced with the value shown in the Examples.

[Adhesive set]
An adhesive set in one embodiment includes a base agent and a curing agent. In the adhesive set of the present embodiment, an adhesive composition (a two-component curable urethane adhesive composition) can be prepared by mixing a base agent and a curing agent. The adhesive composition (two-component curable urethane adhesive composition) cures over time (forms a cured product of the adhesive composition) and can act as an adhesive layer for bonding substrates together.

(A) The main component contains (a) a urethane prepolymer and (b) a silane coupling agent having an alicyclic epoxy group. (A) The main ingredient may further contain (c) a polyisocyanate oligomer having a molecular weight of 1000 or less. (B) The curing agent contains (d) a polyol. At least one of (A) the base agent and (B) the curing agent may further contain any one of (e) curing catalyst, (f) carbon black, (g) filler, or (h) plasticizer. . Each component will be explained below.

(a) Urethane prepolymer Component (a) is a reaction product of (a-1) a compound having two or more active hydrogen groups and (a-2) a polyisocyanate compound having two or more isocyanate groups. Component (a) is preferably a urethane prepolymer having isocyanate groups (as end groups). By reacting such component (a) such that the number of isocyanate groups becomes excessive, a urethane prepolymer having isocyanate groups as terminal groups can be obtained. Note that by using two or more kinds of components (a-1) and/or (a-2), a plurality of components (a), which are reaction products, can exist. Examples of the active hydrogen group include a hydroxy group (OH group), a carboxyl group (COOH group), an amino group (NH ₂ group), and a mercapto group (SH group). As component (a), the reaction product of component (a-1) and component (a-2) may be isolated and used, or the product reacted in the reaction system may be used as it is without isolation. good.

Component (a-1) may be a polyol that is a compound having two or more hydroxy groups (OH groups), for example, it may be a polyether polyol. Examples of polyether polyols include, but are not limited to, polyethylene glycol (PEG), polypropylene glycol (PPG), ethylene oxide/propylene oxide copolymer, polytetramethylene ether glycol (PTMEG), sorbitol polyols, and the like. . One type of polyether polyol may be used alone, or two or more types may be used in combination. Among these, the polyether polyol may be, for example, polypropylene glycol (PPG).

The number average molecular weight of component (a-1) may be 20,000 or less, 18,000 or less, 15,000 or less, or 12,000 or less. When the number average molecular weight of component (a-1) is 20,000 or less, the number of crosslinking points increases and mechanical properties during curing tend to improve. The number average molecular weight of component (a-1) is not particularly limited, but may be, for example, 1000 or more.

In this specification, the "number average molecular weight" is calculated using gel permeation chromatography (GPC) using a standard polystyrene calibration curve.
The GPC measurement conditions are, for example, as follows.
Measuring instrument: ACQUITY UPLC APC system (manufactured by Waters)
Column: APC XT-900, APC XT-200, APC XT-125, APC XT-45 (manufactured by Waters)
Carrier: Tetrahydrofuran (THF)
Detector: Differential refractive index detector Sample: 0.5% by mass THF solution Calibration curve: Polystyrene

Component (a-2) is, for example, an aromatic polyisocyanate in which an isocyanate group is bonded to an aromatic hydrocarbon, an alicyclic polyisocyanate in which an isocyanate group is bonded to an alicyclic hydrocarbon, or an isocyanate group. Examples include aliphatic polyisocyanates bonded to aliphatic hydrocarbons. Component (a-2) may be used alone or in combination of two or more. Among these, component (a-2) may be an aromatic polyisocyanate, for example diphenylmethane diisocyanate. Examples of diphenylmethane diisocyanate include 4,4'-diphenylmethane diisocyanate (4,4'-MDI) and 2,4'-diphenylmethane diisocyanate (2,4'-MDI).

When component (a-1) and component (a-2) are reacted to obtain component (a), if necessary, (a-3) a catalyst for forming a urethane prepolymer may be used. As component (a-3), a known catalyst that promotes the urethanization reaction or ureaization reaction, as exemplified by component (e) (curing catalyst) described below, can be used.

The content of component (a-3) can be adjusted as appropriate depending on the types of components (a-1) and (a-2). The content of component (a-3) is, for example, 0.001 to 5% by mass, 0.005 to 1% by mass, or 0. It may be .01 to 0.1% by weight.

The content of component (a) (total of component (a-1), component (a-2), and component (a-3)) is 20 to 55% by mass, based on the total amount of the main ingredient (A); It may be 25-50% by weight, or 30-45% by weight. When the content of component (a) is 20% by mass or more based on the total amount of the base resin (A), it tends to be possible to prevent a decrease in elongation during curing, and the content of component (a) However, when the amount is 55% by mass or less based on the total amount of the main component (A), it tends to be possible to prevent a decrease in non-primer adhesiveness after curing (after curing).

(b) Silane coupling agent having an alicyclic epoxy group (A) When the main component mainly contains the component (b), it is possible to prepare an adhesive composition exhibiting excellent non-primer adhesion. Become. Although the reason for such an effect is not necessarily clear, for example, the alicyclic epoxy group can react with the NCO group in the main component (A), the primary amino group generated by the decarboxylation reaction of the NCO group, etc. However, these reaction rates are sufficiently slow, and the dehydration condensation reaction between the hydrolyzable groups (alkoxy groups, etc.) in component (b) and the base material progresses, resulting in a strong bond between component (b) and the base material. This is thought to be due to the formation of strong bonds.

Component (b) may be, for example, an organosilicon compound having a hydrolyzable group and an alicyclic epoxy group in the molecule. Examples of the hydrolyzable group include an alkoxy group, and the hydrolyzable group is usually bonded to a silicon atom. The alicyclic epoxy group means a group (monovalent group) in which an unsaturated bond of an alicyclic unsaturated hydrocarbon is epoxidized. Examples of the alicyclic epoxy group include an epoxycyclohexyl group. Although the alicyclic epoxy group may be directly bonded to the silicon atom, it is preferably bonded to the silicon atom via an alkylene group such as a methylene group, ethylene group, or propylene group. Commercially available products of component (b) include, for example, Z-6043 (manufactured by Dow-Toray Industries, Inc.) and KBM-303 (manufactured by Shin-Etsu Chemical Co., Ltd.).

The content of component (b) is 0.01% by mass or more, 0.1% by mass or more, 0.2% by mass or more, or 0.3% by mass or more, based on the total amount of the main ingredient (A). Often, it may be 10% by weight or less, 5% by weight or less, 3% by weight or less, or 1% by weight or less. When the content of the component (b) is 0.01% by mass or more based on the total amount of the main ingredient (A), the adhesiveness to the substrate tends to be further improved. When the content of component (b) is 10% by mass or less based on the total amount of base resin (A), it tends to be possible to better prevent a decrease in adhesive strength due to deterioration of compatibility with other resin components. .

(c) Polyisocyanate oligomer having a molecular weight of 1000 or less When the main component (A) contains the component (c), it becomes possible to prepare an adhesive composition that exhibits excellent non-primer adhesion. The reason for this effect is not necessarily clear, but for example, by changing a part of the isocyanate group (NCO group) component contained in the main component involved in crosslinking to a low molecular weight component, the adhesive composition can be This is thought to be because it became easier to follow the unevenness of the surface. On the other hand, for example, by using a low molecular weight component as a part of the NCO group component of the main agent, the polarity of the adhesive composition and the surface of the base material becomes closer, the wettability of the adhesive composition is improved, and the base material It is also believed that this is because the NCO group component, which may form a covalent bond with the surface, becomes more easily accessible to the base material surface.

Component (c) may be, for example, a multimer of polyisocyanate having two or more isocyanate groups with a molecular weight of 1000 or less, or a multimer of diisocyanate having two isocyanate groups with a molecular weight of 1000 or less. Examples of such polymers include polymers of aliphatic diisocyanates such as hexamethylene diisocyanate (HDI); polymers of aromatic diisocyanates such as diphenylmethane diisocyanate (MDI), and the like. The aliphatic diisocyanate multimer may be, for example, an aliphatic diisocyanate trimer (isocyanurate, biuret, or adduct of trimethylolpropane (TMP)). Component (c) may be used alone or in combination of two or more. The multimer of aliphatic diisocyanate may be a trimer of HDI. The aromatic diisocyanate multimer may be an MDI multimer. Component (c) may contain at least one of an aliphatic diisocyanate polymer with a molecular weight of 1,000 or less and an aromatic diisocyanate polymer with a molecular weight of 1,000 or less. It is preferable to include both the following aliphatic diisocyanate multimers and aromatic diisocyanate multimers with a molecular weight of 1000 or less.

Commercial products of aliphatic diisocyanate polymers (HDI trimers) with a molecular weight of 1000 or less include, for example, Sumidur N3300 (trade name, manufactured by Sumika Bayer Urethane Co., Ltd.) and Duranate 24A-100 (trade name, manufactured by Asahi Kasei Co., Ltd.). (manufactured by Asahi Kasei Corporation), and Duranate E402-100 (trade name, manufactured by Asahi Kasei Corporation). Examples of aromatic diisocyanate multimers (MDI multimers) with a molecular weight of 1000 or less include Millionate MR-100 (trade name, manufactured by Tosoh Corporation), Desmodur VKS20 (trade name, manufactured by Sumika Covestro Urethane Co., Ltd.) ) etc.

The molecular weight of component (c) may be an average molecular weight. The molecular weight or average molecular weight of component (c) is 1000 or less, and may be 900 or less, 800 or less, 700 or less, or 600 or less, or may be 100 or more, 200 or more, 300 or more, or 400 or more. good.

The content of component (c) may be 1 to 15% by weight, 3 to 12% by weight, or 5 to 10% by weight based on the total amount of the main ingredient (A). When the content of the component (c) is 1% by mass or more based on the total amount of the base material (A), the non-primer adhesion improves and the durability of adhesion between the base material surface and the adhesive composition decreases. tend to be preventable. When the content of the component (c) is 15% by mass or less based on the total amount of the main ingredient (A), sufficient flexibility tends to be imparted during curing.

(d) Polyol (d) Component is not particularly limited as long as it is a polyol that is a compound having two or more hydroxy groups (OH groups), but for example, the polyether polyol exemplified by component (a-1) above. It may be. The number average molecular weight of component (d) may be the same as the number average molecular weight of component (a-1). Component (d) may be used alone or in combination of two or more. Component (d) preferably contains a compound having two hydroxy groups (OH groups) and a compound having three or more hydroxy groups (OH groups), since the crosslinking reaction is likely to proceed.

The content of component (d) may be 20 to 60% by weight, 25 to 55% by weight, or 30 to 50% by weight based on the total amount of curing agent (B). When the content of component (d) is 20% by mass or more based on the total amount of curing agent (B), it tends to be possible to prevent a decrease in flexibility of the adhesive composition during curing; When the content of component d) is 60% by mass or less based on the total amount of curing agent (B), it tends to be possible to prevent a decrease in strength during curing.

(d) When the component contains a compound having two hydroxy groups (OH groups) and a compound having three or more hydroxy groups (OH groups), the content of the compound having three or more hydroxy groups (OH groups) is , may be 50% by mass or more, 60% by mass or more, or 70% by mass or more, and may be 100% by mass or less, 95% by mass or less, or 90% by mass or less, based on the total amount of component (d). .

(e) Curing catalyst As component (e), for example, a known catalyst that promotes urethanization reaction or urea formation reaction can be used. Examples of the component (e) include tin-based catalysts and amine-based catalysts. Examples of the tin-based catalyst include dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin didecanate, dioctyltin didecanate, tin 2-ethylhexanoate, and the like. Examples of the amine catalyst include triethylenediamine, bis(dimethylaminoethyl)ether, di(N,N-dimethylaminoethyl)amine, and 1-isobutyl-2-methylimidazole. Component (e) can be appropriately selected depending on the desired curing speed.

The content of component (e) is 0.01 to 5% by mass, 0.1 to 3% by mass, or 0.2 to 1% by mass based on the total amount of (A) main agent and (B) curing agent. It's good. When the content of component (e) is 0.01% by mass or more based on the total amount of the (A) base agent and (B) curing agent, the curing reaction of the adhesive composition tends to be more fully promoted. It is in. If the content of component (e) is 5% by mass or less based on the total amount of (A) main agent and (B) curing agent, it tends to ensure a more sufficient pot life of the adhesive composition. .

(f) Carbon black The component (f) may have an average particle size (D50: particle size at 50% value of a volume particle size distribution curve) of 20 to 40 nm or 25 to 35 nm. By setting the average particle size of component (f) within the above range, the viscosity of the adhesive composition and the dispersibility of component (f) can be adjusted to a more appropriate range, and the workability and strength of the adhesive composition can be improved. There is a tendency to improve. Note that the average particle diameter (D50) of carbon black can be measured by a laser diffraction light scattering method using, for example, "Model LS-230" manufactured by Beckman Coulter.

Commercial products of component (f) include, for example, Monarch 460 (manufactured by Cabot Corporation), Asahi Carbon 70 (manufactured by Asahi Carbon Corporation), Seast 3 (manufactured by Tokai Carbon Corporation), Mitsubishi Carbon 32 (manufactured by Mitsubishi Chemical Corporation). ), Niteron 200 (manufactured by Shin Nikka Carbon Co., Ltd.), and the like.

The content of component (f) may be 5 to 40% by mass or 10 to 30% by mass based on the total amount of (A) the main agent and (B) the curing agent. When the content of component (f) is 5% by mass or more based on the total amount of the (A) main ingredient and (B) curing agent, the strength upon curing tends to improve. When the content of component (f) is 40% by mass or less based on the total amount of (A) main ingredient and (B) curing agent, the dispersibility is further improved, so the strength during curing tends to be maintained. It is in.

(g) Filler (g) Ingredients include kaolin, talc, silica, titanium oxide, calcium carbonate, bentonite, mica, sericite, glass flakes, glass fiber, graphite, magnesium hydroxide, aluminum hydroxide, antimony trioxide. , barium sulfate, zinc borate, alumina, magnesia, wollastonite, xonotrite, whiskers, and the like. Note that the component (f) above is not included in the component (g).

The content of component (g) may be 5 to 40% by mass or 10 to 30% by mass, based on the total amount of (A) main agent and (B) curing agent.

(h) Plasticizer (h) Components include, for example, phthalate ester compounds, alkyl sulfonate ester compounds, adipic ester compounds, and the like. Specific examples of phthalate ester compounds include dioctyl phthalate (DOP), dibutyl phthalate (DBP), diisononyl phthalate (DINP), diisodecyl phthalate (DIDP), butylbenzyl phthalate (BBP), etc. .

The content of component (h) may be 5 to 40% by mass or 10 to 30% by mass, based on the total amount of (A) main agent and (B) curing agent.

At least one of (A) the main agent and (B) the curing agent includes, in addition to the above components (e) to (h), an ultraviolet absorber, a dehydrating agent, a pigment, a dye, an anti-aging agent, an antioxidant, and an antistatic agent. The composition may further contain additives, flame retardants, adhesion agents, dispersants, solvents, and the like.

When mixing the (A) base resin and (B) curing agent, the equivalent ratio (mole ratio) of the isocyanate group (NCO) in the (A) base resin to the hydroxyl group (OH) in the (B) hardener (NCO group/OH) The group) may be, for example, from 1.0 to 5.0. When the equivalence ratio (NCO group/OH group) is 1.0 or more, sufficient non-primer adhesiveness can be obtained because the proportion of unreacted polyol is reduced when the main agent and curing agent are mixed. There is a tendency. When the equivalence ratio (NCO group/OH group) is 5.0 or less, the presence ratio of isocyanate and prepolymer will be in an appropriate range when the base resin and curing agent are mixed, so that they will not interact with moisture in the air. The reaction rate can be suppressed and sufficient curability tends to be obtained. Note that the isocyanate groups in the main agent (A) are mainly derived from the components (a) and (b), and the hydroxy groups in the curing agent (B) are mainly derived from the component (d).

In the adhesive set of the present embodiment, an adhesive composition (a two-component curable urethane adhesive composition) can be prepared by mixing (A) the main ingredient and (B) the curing agent. The temperature and time for mixing the (A) base agent and (B) curing agent may be, for example, 10 to 35° C. and 1 to 60 minutes.

The method of mixing (A) the main agent and (B) curing agent is not particularly limited, and for example, it may be a method of mixing by hand painting using a normal caulking gun, and a method of mixing by hand painting using a normal caulking gun may be used. A method of mixing using a mechanical rotary mixer, a static mixer, etc. using a combination of a pump (for example, a gear pump, a plunger pump, etc.) and a throttle valve may also be used.

The prepared adhesive composition (two-component curable urethane adhesive composition) can be cured (cured) to form a cured product, which acts as an adhesive layer for bonding substrates together. It is possible. The conditions for curing the adhesive composition (curing conditions) may be, for example, 10 to 35° C., 30 to 60% RH (relative humidity), and 2 to 7 days.

The structure of one embodiment includes a first base material, a second base material, and an adhesive layer that adheres the first base material and the second base material to each other. The adhesive layer contains a cured product of an adhesive composition containing a main agent and a curing agent in the adhesive set described above. Examples of structures include vehicle back doors, trunk lids, windshields, spoilers, and the like.

At least one of the first substrate and the second substrate may be a polypropylene (PP) substrate, and both the first substrate and the second substrate may be a polypropylene (PP) substrate. You can. Examples of base materials other than polypropylene (PP) base materials include polyvinyl chloride, acrylonitrile/butadiene/styrene copolymer (ABS), polycarbonate (PC), polyamide (PA), poly(methyl methacrylate (PMMA)), polyester, Plastic base materials such as epoxy resin, polyurethane (PUR), polyoxymethylene (POM), polyethylene (PE), ethylene/propylene copolymer (EPM), ethylene/propylene/diene polymer (EPDM), carbon fiber reinforced plastic (CFRP) , fiber-reinforced plastic base materials such as glass fiber reinforced plastic (GFRP), resin compound base materials such as sheet molding compound (SMC), etc. When the structure is a vehicle back door, the first base material is The inner panel may be made of a polypropylene base material, and the second base material may be an outer panel made of a base material other than the propylene base material.

A method for manufacturing a structure according to one embodiment includes a step of bonding a first base material and a second base material together via an adhesive composition containing a base material and a curing agent. The temperature and time when mixing the (A) main ingredient and (B) curing agent in the adhesive set, the conditions for curing the adhesive composition, etc. are the same as described above.

Hereinafter, the present disclosure will be described in more detail with reference to Examples. However, the present disclosure is not limited to these examples.

[Preparation of base agent intermediate product]
Preminol 3012 (polyether polyol (polymer of propylene glycol using glycerin as an initiator), manufactured by Asahi Glass Co., Ltd., number average molecular weight: 12,000, Number of hydroxy groups: 3) 38.0 g, Monarch 460 (carbon black, manufactured by Cabot Corporation) 13.3 g, Iceberg (calcined kaolin, manufactured by Shiroishi Calcium Co., Ltd.) 19.0 g, and DINP (diisononyl phthalate) 22.1 g was charged and stirred at room temperature (25°C) for 60 minutes until there were no lumps of carbon black. Next, the kneading container was heated until the temperature of the contents reached 100° C., the pressure inside the kneading container was reduced to 2.7 kPa (20 mmHg) using a vacuum pump, and the contents were stirred for 1 hour. Next, the contents were cooled until the temperature reached 40°C, and 3.8 g of Millionate MT (4,4'-diphenylmethane diisocyanate, manufactured by Tosoh Corporation, NCO content: 33.6%) and Dabco T- were added to the kneading container. After adding 0.008 g of 9 (tin-based catalyst, stannous octoate (tin 2-ethylhexanoate), manufactured by Air Products and Chemical Co.), nitrogen was introduced and the contents were heated until the temperature reached 70°C. The kneading vessel was heated and the contents were stirred for 1 hour. The temperature of the contents was cooled to 40° C., and 3.8 g of Sumidur N3300 (isocyanurate of hexamethylene diisocyanate (HDI), manufactured by Sumika Bayer Urethane Co., Ltd., molecular weight: 504.6) was added. Stir for a minute. The viscous material obtained in the above steps was used as a main agent intermediate product. The viscous material is presumed to contain a urethane prepolymer, which is a reaction product of Preminol 3012 and Millionate MT.

[Preparation of curing agent intermediate product]
In a kneading container equipped with a stirrer, a nitrogen inlet pipe, a vacuum pump, and a heating/cooling device, 32.3 g of EXCENOL 837 (polypropylene glycol, manufactured by Asahi Glass Co., Ltd., number average molecular weight: 6000, number of functional groups: 3), EXCENOL 2020 (polypropylene glycol) , manufactured by Asahi Glass Co., Ltd., number average molecular weight: 2000, number of functional groups: 2) 8.1 g, EDP-1100 (ethylenediamine propylene oxide modified product, number of functional groups: 4, hydroxyl value: 214 mgKOH/g) 0.8 g, Monarch 460 (same as above), 24.2 g of Iceberg (same as above), and 17.0 g of DINP (same as above) were added, and the mixture was stirred at room temperature (25° C.) for 30 minutes until there were no lumps of carbon black. Next, the kneading container was heated until the contents reached 100° C., the pressure inside the kneading container was reduced to 2.7 kPa (20 mmHg) using a vacuum pump, and the contents were stirred for 1 hour. The temperature of the contents was cooled to 40°C, and 0.1 g of BHT (dibutylhydroxytoluene), 0.6 g of dehydrating molecular sieve 4A (dehydrating agent), and Texnol IBM-12 (amine catalyst, 1-isobutyl- 0.8 g of 2-methylimidazole (manufactured by Nippon Nyukazai Co., Ltd.) was added and stirred for 30 minutes. The viscous material obtained in the above steps was used as an intermediate curing agent.

[Preparation of adhesive set]
<Example 1>
(base agent)
Example 1 was prepared by adding 0.5 g of Z-6043 (2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, manufactured by Dow-Toray Industries, Inc.) to the above base agent intermediate product and stirring for 10 minutes. The main ingredient was obtained.
(hardening agent)
The above curing agent intermediate product was used as a curing agent in Example 1 as it was.

<Comparative example 1>
(base agent)
The above main agent intermediate product was used as the main agent in Comparative Example 1 as it was.
(hardening agent)
The above curing agent intermediate product was used as a curing agent in Comparative Example 1 as it was.

<Comparative example 2>
(base agent)
Add 0.5 g of KBE-403 (3-glycidoxypropyltriethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd., a silane coupling agent having an alicyclic epoxy group) to the above intermediate base ingredient, and stir for 10 minutes. Thus, a main ingredient of Comparative Example 2 was obtained.
(hardening agent)
The above curing agent intermediate product was used as a curing agent in Comparative Example 2 as it was.

<Comparative example 3>
(base agent)
The main agent of Comparative Example 3 was obtained by adding 0.5 g of KBM-573 (N-phenyl-3-aminopropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.) to the intermediate main agent and stirring for 10 minutes. .
(hardening agent)
The above curing agent intermediate product was used as a curing agent in Comparative Example 3 as it was.

[Adhesiveness test]
<Preparation of test specimen>
Two base materials whose main component was polypropylene (PP) that had been subjected to flame treatment were prepared. The base resin and curing agent of Example 1 and Comparative Examples 1 and 2 were mixed at a mass ratio (approximately : curing agent=1:1). The obtained adhesive composition is applied to one base material to a thickness of 3 mm, and the adhesive composition is bonded to the surface of the other base material so that the adhesion area is 250 mm ² (25 mm x 10 mm), and pressure bonded. A laminate was obtained by this. The obtained laminate was cured at 23° C. for 72 hours to obtain a test piece in which the base materials were adhered to each other via an adhesive layer containing a cured product of the adhesive composition. In addition, in the following adhesion test, different test specimens were used for each condition.

<Adhesion test>
(Initial conditions)
The obtained test specimen was subjected to a tensile test at 23° C. in accordance with JIS K6850:1999 to determine the shear strength (breaking strength).

(High temperature (90℃) condition)
The obtained test specimen was heated at 90° C. for 1 hour and subjected to a tensile test under the same conditions as the initial conditions at 90° C. to determine the shear strength (breaking strength). In addition, under high temperature (90°C) conditions, from the perspective of eliminating the effects of board sagging, etc., we prepared a test specimen with a backing material (metal plate) attached to the opposite side of the board from the adhesive layer. was evaluated.

(High temperature (80℃) condition)
The obtained test specimen was heated at 80° C. for 1 hour and subjected to a tensile test under the same conditions as the initial conditions at 80° C. to determine the shear strength (breaking strength). Note that under high temperature (80°C) conditions, as with high temperature (90°C) conditions, a backing material (metal plate) is placed on the opposite side of the board from the adhesive layer in order to eliminate effects such as sagging of the board. A bonded test piece was prepared and evaluated in the same way.

(Heat-resistant)
The obtained test specimens were heated at 90°C for 336 hours or 90°C for 500 hours, cooled at 23°C for 1 day, and then subjected to a tensile test at 23°C under the same conditions as the initial conditions. , the shear strength (breaking strength) was determined.

(hot water resistance)
The obtained test specimens were treated by immersing them in hot water at 40°C for 336 hours or immersing them in hot water at 40°C for 500 hours, then cooled and dried at 23°C for one day, and then heated at 23°C under the same conditions as the initial conditions. A tensile test was conducted to determine the shear strength (breaking strength).

The composition of the materials is shown in Table 1, and the test results are shown in Table 2.

As shown in Table 2, the adhesive composition prepared from the adhesive set of Example 1 containing a predetermined base agent and a predetermined curing agent is different from the adhesive composition prepared from the adhesive set of Comparative Examples 1 to 3, which does not meet these requirements. It exhibited higher shear strength under each condition compared to the prepared adhesive composition. These results confirmed that the adhesive set of the present disclosure makes it possible to prepare an adhesive composition exhibiting excellent non-primer adhesion.

Claims (3)

An adhesive set including a main agent and a curing agent,
The main agent contains a urethane prepolymer and a silane coupling agent having an alicyclic epoxy group,
the curing agent contains a polyol;
adhesive set. a first base material;
a second base material;
an adhesive layer that adheres the first base material and the second base material to each other;
Equipped with
The adhesive layer contains a cured product of an adhesive composition including the base agent and the curing agent in the adhesive set according to claim 1.
Structure. A method for manufacturing the structure according to claim 2, comprising:
a step of bonding the first base material and the second base material via an adhesive composition containing the base agent and the curing agent;
Method of manufacturing the structure.