JPH08245940A - Moisture-curing type one pack elastic liquid polyurethane adhesive - Google Patents

Abstract

PURPOSE: To obtain a moisture-curing type one pack elastic adhesive comprising an NCO-terminated urethane prepolymer, an oxazolidine ring-containing compound, and a bis(morpholinoethyl)ether compound, expressing a strong adhesive force at an early time, long in the pot life, and expressing a low viscous liquid property in spite of no solvent. CONSTITUTION: This adhesive comprises (A) 100 pts.wt. of an isocyanate group- terminated urethane polymer produced from a polyol (preferably a condensation type polyester polyol produced by the condensation reaction of a polyhydric alcohol with a polybasic carboxylic acid, a hydroxy group-terminated polybutadiene, or a rosin-modified polyol having a rosin skeleton in the molecule), (B) 0.1-30 pts.wt. of a compound having two or more oxazolidine rings in the molecule, and (C) 0.1-10 pts.wt. of a bis(morpholinoethyl)ether compound.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polyurethane adhesive. More specifically, the present invention exhibits a strong adhesive force at an early stage, has a long holding time, and finally has a function of shifting from adhesive to adhesive, and exhibits a low-viscosity liquid property while being solvent-free. The present invention relates to a one-component elastic moisture-curable urethane adhesive.

[0002]

2. Description of the Related Art Conventional solvent-based urethane adhesives are used to dilute a solid or viscous starch syrup-like resin with an organic solvent in order to give initial tackiness, and to dilute the adhesive before the bonding work. The initial tack was imparted by volatilizing the organic solvent. On the other hand, a solventless urethane adhesive needs to be led to a low-molecular-weight prepolymer in order to be liquid at room temperature, but the low-molecular-weight prepolymer inherently has a very weak initial tack. It was impossible to give an excellent initial tack when the organic solvent of the solvent-based urethane resin was volatilized. For this reason, a solventless urethane adhesive is formed into a solid or viscous starch syrup at room temperature, and is heated to melt during the bonding work to be turned into a liquid, which is then cooled to provide initial tackiness. However, there is an adverse effect that heating promotes a complicated process of heating and melting and volatilization of harmful unreacted monomers by heating, and the present situation is that the characteristic of no solvent is significantly reduced.

Isocyanate-terminated urethane prepolymers (hereinafter simply referred to as "prepolymers") are prepared by various methods in which amine-based catalysts (including block-type amine-based catalysts) are used to accelerate or adjust the reaction with water in the atmosphere. Attempts have also been made to produce a one-part moisture-curing urethane-based adhesive containing as a main component. However, these methods
The purpose was to provide a rapid curing rate based on the adjustment of the reaction with water, and to maintain long-term stability under the trade-off with the curing rate even if a catalyst was added internally. . Therefore, when various amine-based catalysts (including block-type amine-based catalysts) currently on the market are mixed with the prepolymer, the curing speed can be adjusted and the one-component stability can be maintained for a considerably long time. However, it is not possible to develop a high degree of initial adhesion in a short time and maintain the adhesion for a long time.

In general, an adhesive which exhibits rapid curing has a short storage period after compounding with a catalyst and is rapidly led to a gel so that the initial tackiness is poor and the tackiness does not last, and can be used under very limited conditions. It's just a thing. On the other hand, an adhesive containing a catalyst such as an amine catalyst or a block-type amine catalyst has a very slow initial onset time of only a few hours, and its adhesive strength gradually increases. It is difficult to say that it is very practical because it cannot obtain a good temporary adhesion state and must continue the press work for a long time, so that only inefficient working conditions can be obtained.

[0005]

Means for Solving the Problems The present inventors have developed, in a solventless one-component moisture-curable urethane adhesive, early development of a high degree of initial tackiness observed in solvent-based urethane adhesives. Even if the material is strong and repulsive for a long time, it can be easily temporary bonded and work easily, and moreover, a highly reliable adhesive that does not cause the rheological defects of the pressure sensitive adhesive after a certain time has elapsed is possible. We have earnestly conducted research to provide adhesives based on the new concept. As a result, (A) an isocyanate-terminated urethane prepolymer composed of polyol and polyisocyanate,
Only a urethane resin composition obtained by blending (B) a compound having two or more oxazolidine rings in the molecule and (C) bis (morpholinoethyl) ethers has an extremely high initial adhesion in a short time of about several minutes. It has been found that it can be applied, and that it can be applied for several hours and, after a few days, it can be applied with highly reliable adhesive physical properties, and the present invention has been completed here.

That is, the present invention provides (A) an isocyanate-terminated urethane prepolymer composed of a polyol and polyisocyanate, (B) a compound having two or more oxazolidine rings in the molecule, and (C) bis (morpholinoethyl) ether. The present invention relates to a one-component elastic moisture-curable liquid urethane adhesive containing a class of compounds.

Only when the above-mentioned components (A), (B) and (C) are blended, the foaming at the time of thick coating, which is recognized in general urethane adhesives, is reduced, and the coating amount of the adhesive, Adhesion work can be performed freely without any restrictions on usage conditions. Furthermore, when the transition from tackiness to adhesion occurs, not only self-crosslinking due to water but also the reaction between the isocyanate group and the imino group and hydroxyl group generated by the opening of the oxazolidine ring give the polymer physical properties with high elasticity, resulting in elastic adhesion. The function of the agent can also be imparted.

In the present invention, the compound having two or more oxazolidine rings in the molecule which is used as the component (B) is a latent catalyst which decomposes with a ketimine type, aldimine type or enamine type compound by water to give an active hydrogen compound. As well known compound (JP-A-7-10
949, etc.). However, when the component (B) is blended into the prepolymer alone, the storage stability is good,
Although the amount of foaming is small, the onset of initial adhesion is very slow, and the adhesion is weak so that the adhesive state required for temporary adhesion cannot be obtained at all.

The bis (morpholinoethyl) ethers used as the component (C) are general amine-based catalysts and are commonly used in the production of urethane foams, etc., and are commonly called foam-type urethane-based catalysts. (JP-A-2-308
885, JP-A-4-239582, and JP-A-5-
No. 117619). However, when the component (C) is blended into the prepolymer alone, the initial tackiness is developed in a short time, but since the gelation proceeds rapidly from that state, the tackiness retention time is extremely short, and the foam-type catalyst Because of this, foaming is large.

However, when the above-mentioned components (B) and (C) are blended with the prepolymer, not only the time required for developing the initial tackiness due to the component (C) is further shortened but also the initial tackiness itself is enhanced. To be done. Moreover, since the excellent adhesive state is maintained for several hours, it is possible to secure a long bonding time. Moreover, in a state in which the foaming by the component (C) is extremely suppressed, the adhesive steadily shifts to adhesive with excellent elasticity and high reliability.

In the present invention, the isocyanate-terminated urethane prepolymer used as the component (A) is composed of a polyol and a polyisocyanate.

As the polyol of the present invention, conventionally known ones can be widely used as long as they are polyhydric alcohols having two or more hydroxyl groups at the molecular ends. Specifically, when classifying by chemical bond in the molecule such as polyether polyol and polyester polyol, the following polyols can be exemplified.

That is, as the polyether polyol having an ether bond in the molecule, polyoxyalkylene diols (specifically, polyoxyethylene glycol, polyoxypropylene glycol, polyoxybutylene glycol and the like and copolymers thereof), Polyoxyalkylene polyols such as polyoxyalkylene triols (specifically, those obtained by addition-polymerizing ethylene oxide, propylene oxide, butylene oxide, styrene oxide, etc. with glycerin, trimethylol propane, etc.), other bisphenols, sugars, amines, etc. Starting materials include ethylene oxide or propylene oxide-added diols, polyether polyols, and polyoxytetramethyl glycol obtained by ring-opening polymerization of tetrahydrofuran. Rukoto can.

As the polyester polyol having an ester bond in the molecule, conventionally known compounds can be widely used as long as they are compounds having an ester bond as a repeating unit and having a hydroxyl group at the terminal. Specifically, a condensation-type polyester polyol obtained by dehydration condensation of a polycarboxylic acid (mainly adipic acid or phthalic acid) and a polyhydric alcohol (specifically glycol, triol, etc.); ε-
Lactone-based polyester polyol obtained by ring-opening polymerization of caprolactone; polycarbonate diol obtained by phosgenation of polyol or transesterification reaction with diphenylene carbonate; polyester polyol by polyaddition reaction of polycarboxylic acid anhydride and diepoxide; A urethane-modified polyester polyol in which a urethane group or the like is introduced can be given.

Polyols other than those mentioned above include hydroxyl-terminated polybutadiene (1,2-adduct, 1,4-adduct), so-called rosin-modified polyol having a rosin skeleton in the molecule, polyol having an amine structure in the molecule, So-called silicon-based diols in which carbinol is introduced into both ends of polysiloxane called carbinol-modified silicone oil, so-called acrylic polyols having acrylic acid ester (including methacrylic acid ester) as a skeleton, and skeleton of fluororesin ( For example, a so-called fluororesin polyol having a hydroxyl group at the end of (copolymer resin of ethylene difluoride and acrylic) can be exemplified.

In the present invention, these polyols may be used alone or in combination of two or more.

Among these polyols, polyoxyalkylene diols and polyoxyalkylene triols are preferably used because of their low viscosity and easy liquefaction, and diethylene glycol and hexyl glycol among polyester polyols are provided because they impart excellent adhesiveness. ,
Condensed polyester polyols obtained by the condensation reaction of polyhydric alcohols such as neopentyl glycol and polycarboxylic acids such as adipic acid, sebacic acid, isophthalic acid and trimellitic acid, hydroxyl-terminated polybutadiene (among others, 1,2- It is preferable to use an adduct) and a rosin-modified polyol having a rosin skeleton in the molecule.

The polyisocyanate used in the present invention is a compound having two or more isocyanate groups in one molecule, a so-called polyfunctional isocyanate compound. As such a polyfunctional isocyanate compound, conventionally known compounds can be widely used, and examples thereof include 2,4-toluene diisocyanate (hereinafter referred to as "2,4-TDI") and 2,6-toluene diisocyanate (hereinafter referred to as "2,6- TDI "), an isomer mixture of 2,4-TDI and 2,6-TDI, 4,4'-diphenylmethane diisocyanate (hereinafter referred to as"4,4'-MDI"),2,4'-diphenylmethanediphenyldiisocyanate (Hereinafter "2,4 '
-MDI "), 4,4'-MDI and 2,4'-M
Isomeric mixture with DI (trade name: luplanate MI, manufactured by BSF Japan), carbodiimide-modified MD
I, polymethylene polyphenyl polyisocyanate (hereinafter referred to as "polymeric MDI"), hexamethylene diisocyanate (hereinafter referred to as "HMDI"), xylene diisocyanate (hereinafter referred to as "XDI"), metaxylene diisocyanate, 1,5-naphthalene diisocyanate, hydrogen MDI, hydrogenated TDI, hydrogenated XDI,
Isocyanate compounds such as isophorone diisocyanate; Buret polyisocyanate compounds such as Sumidule N (Sumitomo Bayer Urethane Co.); Desmodur IL, HL (Bayer AG), Coronate EH
(Manufactured by Nippon Polyurethane Industry Co., Ltd.) and other polyisocyanate compounds having an isocyanate ring; and adduct polyisocyanate compounds such as Sumidule L (manufactured by Sumitomo Bayer Urethane Co.) and Coronate HL (manufactured by Nippon Polyurethane Industry Co., Ltd.). it can.

In the present invention, these polyisocyanates may be used alone or in admixture of two or more.

In these polyisocyanates, fast curing,
4,4 ', which has excellent retention of strong adhesion and long-term adhesion
Aromatic polyisocyanates such as -MDI, a mixture of 4,4'-MDI and 2,4'-MDI, 2,4-TDI, a mixture of 2,6-TDI and its isomers, and a polymeric MDI are preferable.

The prepolymer composed of polyol and polyisocyanate is obtained by reacting one or more kinds of the above polyols with one or more kinds of excess polyisocyanates.

There is no particular limitation in synthesizing the prepolymer, and it may be produced by a conventionally known method. The excess polyisocyanate means that the isocyanate equivalent is in excess of the OH group equivalent of the polyol, and the equivalent relationship can be expressed by the NCO / OH ratio. That is, theoretically, when the NCO / OH ratio is 1 or more, isocyanate terminals can be obtained, but since the present invention is characterized in that it is liquid, the NCO / OH ratio is usually preferably 1.5 or more. The upper limit of the NCO / OH ratio is not particularly limited, but an NCO / OH ratio of 10.0 or less is more preferable.
In particular, in order to obtain a liquid and low-viscosity prepolymer, it is necessary to consider the type of the polyol, the number of functional groups, the molecular weight, etc.
It is particularly preferable to adjust the CO / OH ratio to about 2.0 to 10.0. Although the polymerization temperature and the polymerization time are not particularly limited, it is usually preferable that the polyol and the polyisocyanate are mixed under a nitrogen stream and then reacted at 60 to 100 ° C. for 3 to 8 hours. Before the reaction, during the reaction, and after the completion of the reaction, an appropriate amount of organometallic salt-based urethane polymerization catalyst, stabilizer, moisture promoter, polymerization regulator, etc. may be added at any time.

The compound having two or more oxazolidine rings in the molecule used as the component (B) in the present invention has a structural formula

[0024]

Embedded image

[In the formula, R ¹ represents a hydrogen atom, a C ₁ -C ₆ alkyl group or a phenyl group. ] It is a compound which has a functional group represented by this.

The compound having two or more oxazolidine rings in the molecule is, for example, a method of using an excess amount of a hydroxy compound having an oxazolidine ring and adding it to a polyisocyanate such as diisocyanate, or a polycarboxylic acid such as dicarboxylic acid. Can be produced by a condensation reaction method or the like, but is not limited to these methods. In short, it does not matter if two or more oxazolidine rings are present in the molecule.

The oxazolidine ring of the above compound is hydrolyzed by water to form an amine polyol and an aldehyde as shown by the following formula.

[0028]

Embedded image

In the present invention, as the component (B), which has an excellent interaction with the component (C), has a strong effect of developing an early initial tack, and can retain adhesion for a long time, the following structural formula

[0030]

Embedded image

[Wherein R ¹ is the same as above. ] It is preferable to use bis (N-ethyl-2-alkyl-1,3-oxazolidine) carbonate represented by Among such bis (N-ethyl-2-alkyl-1,3-oxazolidine) carbonates, the compound in which R ¹ is an isopropyl group is particularly preferable because it is further excellent in the interaction with the component (C).

The bis (morpholinoethyl) ethers used as the component (C) in the present invention are those represented by the general formula

[0033]

[Chemical 4]

[Wherein R ² is a C ₁ -C ₃ alkyl group,
n shows the integer of 0-4. ] It is a compound represented by these.

Bis (morpholinoethyl) ethers are
It is called a foam-type amine-based catalyst that has excellent storage stability and promotes the reaction between isocyanate groups and water, which is suitable for the production of urethane foam. It has excellent storage stability as well as the production of urethane foam. It is a general urethane polymerization catalyst used in many applications such as caulking materials.

As a characteristic of its molecular structure, it is a compound in which a tertiary amine in a morpholine skeleton exists symmetrically and has a high hygroscopicity because it easily forms a hydrogen bond, and due to its high hygroscopicity, it is based on the morpholine structure. It is known that the presence of a tertiary amine enhances the absorption of moisture in the prepolymer and imparts moisture curability as efficiently as other morpholine-based urethane polymerization catalysts. However, in the compound having an oxazolidine ring and the compound in which the oxazolidine ring is opened by moisture, it is difficult to recognize an interaction involving a chemical reaction other than a hydrogen bond with the component (C).
Therefore, when both the component (B) and the component (C) are present in the urethane prepolymer having an isocyanate group, the component (C) actively absorbs moisture to accelerate the hydrolysis of the oxazolidine ring and simultaneously absorb moisture. By coexisting with the imino group and the hydroxyl group generated together with the water content, the complex action on the isocyanate group leads to the early development of a strong initial tack and a phase of maintaining the adhesive state for a long time without gelation all at once. It is presumed that the contradictory effects of the present invention are given.

In the component (C), n in the above general formula is 0, 1
Or a bis (morpholinoethyl) ether which is 2, more specifically a bis (morpholinoethyl) ether in which n = 0, bis (2,6-dimethylmorpholinoethyl) in which n = 1 and R is a methyl group. ) Ether or bis (3,5-dimethylmorpholinoethyl) ether,
It is preferable because it has an excellent interaction with the component (B). These structures are as follows:

Bis (morpholinoethyl) ether has the chemical structural formula

[0039]

Embedded image

It is represented by

Bis (2,6-dimethylmorpholinoethyl) ether has the chemical structural formula

[0042]

[Chemical 6]

It is represented by

Bis (3,5-dimethylmorpholinoethyl) ether has the chemical structural formula

[0045]

[Chemical 7]

It is represented by

The blending ratios of the component (A), the component (B) and the component (C) in the present invention are not particularly limited, but the ratio of the component (B) to 100 parts by weight of the component (B) is 0.
1 to 30 parts by weight and (C) component may be selected and blended in the range of 0.1 to 10 parts by weight. If the blending amount of the component (B) is less than 0.1 parts by weight, it tends to be difficult to maintain the tackiness for a long time, and conversely, if it exceeds 30 parts by weight, it becomes a permanent tack and adheres from the tackiness. It tends to be difficult to move to. When the amount of the component (C) is less than 0.1 parts by weight, the initial tack tends to be delayed and the tack tends to be poor. On the contrary, when it exceeds 10 parts by weight, a rapid gel is caused early. The adhesive holding time becomes short, and the foaming also becomes large, so that the storage stability tends to deteriorate.

The preferred blending ratio for obtaining the effect of the present invention is 1 to 1 of the component (B) per 100 parts by weight of the component (A).
0 parts by weight and 0.5 to 5 parts by weight of the component (C).
In this way, the adhesive of the present invention which can be transferred from tackiness to adhesion in a small foaming state through the early expression of initial tack, the strength of tackiness, and the control of the tackiness retention time has a proportion of the above-mentioned compounding ratio in a desired form. It is easily prepared by arbitrarily selecting.

Although there is no particular limitation on the timing of blending the components (B) and (C), it is usually preferable to blend the component (A) while avoiding the influence of water. The order of adding the component (B) and the component (C) is not particularly limited. Alternatively, during the reaction between the polyol and the polyisocyanate, for example, in the latter stage of the reaction,
The components (B) and (C) may be blended while avoiding the influence of water.

Thus, in the present invention, a solvent-free adhesive which is liquid and has a functional group capable of reacting with the isocyanate group due to ring opening together with moisture absorption and moisture by the additive action of the components (B) and (C) Due to the continuous action of generation and catalytic effect, strong initial adhesiveness is developed early in a state where there is little foaming, and this gives a continuous adhesive holding state that can be stuck for a long time,
It is intended to provide an adhesive having excellent long-term storage stability that shifts from tackiness to adhesion. Moreover, not only the formation of a urea bond, which is the center of the reaction with the isocyanate group due to moisture, which is often found in ordinary moisture-curable urethanes, but also the imino group and the hydroxyl group formed by the ring opening of the oxazolidine ring with the isocyanate group The urethanization reaction gives the polymer properties that are extremely elastic and can also serve as a flexible elastic adhesive.

Further, in the urethane resin composition of the present invention, various conventionally known additives such as plasticizers, high boiling point solvents, thermoplastic polymers, tackifying resins, coupling agents, antioxidants, ultraviolet absorbers, White pigments such as titanium white, various color pigments, paints, fillers such as calcium carbonate, carbon black, clay, talc, etc. can be appropriately blended according to the use and purpose.

[0052]

EFFECT OF THE INVENTION Since the urethane adhesive of the present invention shows a liquid state in the room temperature range, it can be easily applied, and the initial adhesiveness is given by the moisture in the air in a short time to maintain the initial adhesiveness. A new one that can be stored for a long time with a single liquid that imparts adhesiveness and fixes the adherend within a range that does not move, and then continues the room temperature crosslinking with moisture in the air to give the function of shifting from adhesive to adhesive in a low foaming state It is a concept adhesive. Moreover, the urethane-based adhesive of the present invention is a new adhesive that does not contain any organic solvent that causes various problems such as environmental pollution, health hazard to human body, safety such as fire, so-called environmental load as much as possible. It is also a proposal for a drug.

The advantages of the urethane adhesive of the present invention will be described in more detail below.

(1) The urethane-based adhesive of the present invention is a one-liquid type, solvent-free type, and shifts from adhesion to adhesion by moisture in the atmosphere in an atmosphere of 5 ° C. or higher. Therefore, compared to solvent-based urethane containing harmful organic solvent and reactive urethane hot-melt adhesive that releases harmful isocyanate by heating, it has solved various problems in safety such as environmental pollution, health hazard to human body and fire. It is possible to provide an adhesive that exerts less load on the so-called environment.

(2) The urethane adhesive of the present invention is
Not only the feature of (1), but because it is liquid and has little foaming, it can be applied easily and at the same time the amount of application can be freely selected and thick coating can be performed. Moreover, in a short time of about 10 minutes, sufficient initial adhesiveness can be developed for temporarily adhering the adherend material having resilience, and the good adhesive state can be maintained for about 90 minutes. It has the great advantage that it can. Therefore, the urethane-based adhesive of the present invention has an unprecedented convenience and can significantly improve the efficiency of the bonding work.

(3) Since the urethane-based adhesive of the present invention can be hardened in about one day from sticking to obtain a urethane polymer having a high elasticity, it has a flexible and flexible adhesive state of elastic adhesion. It is also possible to obtain.

(4) Since the urethane-based adhesive of the present invention is a one-liquid type liquid, it can be stored in a watertight or airtight container such as a commercially available cartridge type container and has excellent long-term stability. Since it has it, there is also an advantage that the inventory in the market can be taken for a long time. Therefore, it can be applied to a wide range of applications in a simple state.

[0058]

EXAMPLES The present invention will be described more in detail with reference to examples of the present invention, but the present invention is not limited to these examples. In the following, the terms “part” and “%” simply mean “part by weight” and “% by weight” unless otherwise specified.

Example 1 A polyoxypropylene triol obtained by adding propylene oxide to glycerin as a polyoxyalkylene triol was placed in a 2-liter four-neck separable flask equipped with a stirrer, a thermometer, a vacuum dehydrator and a nitrogen gas stream device. (Number average molecular weight 5000, hydroxyl value 33.5, number of hydroxyl groups per molecule 3, viscosity 500 mPa · s / 25 ° C., trade name: Polyhardener T-500, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.)
500 parts and polyoxypropylene diol as polyoxyalkylene diol (number average molecular weight 2000,
Hydroxyl value 55.8, 2 hydroxyl groups per molecule, viscosity 3
00mPa · s / 25 ° C, product name: Sumifene 360
0, manufactured by Sumitomo Bayer Urethane Co., Ltd.) was mixed in an amount of 500 parts.
This mixed polyol has a hydroxyl value of 44.7. This mixed polyol was dehydrated at 100 ° C. at 15 torr for 1 hour and then cooled to 50 ° C. to obtain 2,4-TDI as polyisocyanate (isocyanate content of 48.
139 parts of 3%, trade name: Sumijour T-100, manufactured by Sumitomo Bayer Urethane Co., Ltd. This NCO / OH
The ratio is 2.0 and the designed isocyanate content is 2.95.
%. 90% of this polyol and polyisocyanate
A prepolymer was obtained by reacting at ˜95 ° C. for 4 hours and cooling. This prepolymer has an isocyanate content of 2.9.
The viscosity was 0% and the viscosity was 7,000 mPa · s / 25 ° C. This prepolymer is referred to as "prepolymer A".

Invention 1 means bis (N-ethyl-2-isopropyl-1,3-oxazolidine) carbonate (CAS) as component (B) per 100 parts of prepolymer A.
Registration number: 145899-78-1, hereinafter referred to as "oxazolidine curing agent A"), 5 parts, and 2 parts of bis (2,6-morpholinoethyl) ether as the component (C) were mixed under a nitrogen stream and stirred for 20 minutes. And an adhesive having a viscosity of 6800 mPa · s / 25 ° C. obtained after homogeneous mixing. The viscosity at this time was defined as the initial viscosity.

Comparative Example 1 was obtained by mixing 7 parts of the bisoxazolidine curing agent as the component (B) per 100 parts of the prepolymer A and mixing the resulting mixture for 20 minutes, and then obtaining a viscosity of 6700 m.
Pa · s / 25 ° C adhesive.

Comparative Example 2 was prepared by adding 7 parts of bis (2,6-morpholinoethyl) ether as the component (C) per 100 parts of the prepolymer A, and after mixing for 20 minutes, the viscosity was 6900 mPa · s. / 25 ° C adhesive.

The time of onset of initial tack of these three adhesives,
The initial adhesive strength, the possible bonding time, the adhesive properties and the storage stability were evaluated by the following methods.

Initial Adhesion Development Time: The initial adhesion development time was measured by coating each of the above adhesives on a glass plate at 20 ° C. and a relative humidity of 60%, and then a polyethylene film (width: 25 mm) at regular intervals. ) Was pasted and immediately subjected to a 90 ° peel test (peel rate: 100 mm / min), and the point at which the peel strength exceeded 5.0 N / 25 mm width was defined as the initial expression time.

Initial adhesion strength: Measured according to the above 90 ° peeling test, and the strength showed the maximum value within the possible bonding time.

Bondable time: The time at which the adhesive did not transfer to the bonded polyethylene film was defined as the bondable time.

Adhesion strength: 0.2 mm thick coated steel plate / cover (each width: 25 mm) was used as an adherend, and after adhesion, 20
90 ° peeling test (peeling speed: 5 mm / min and 100
mm / min) and the adhesive strength was measured.

Storage stability: Various adhesives enclosed in a glass bottle were stored in an oven at 50 ° C. for 30 days and then stored at 25.
The temperature was adjusted to ° C and the viscosity was measured. The viscosity at this time was defined as the post-acceleration viscosity. Using the post-acceleration viscosity and the initial viscosity, the viscosity increase rate was determined according to the following formula, and was defined as the storage stability. Those having a viscosity increase rate of more than 40% were considered to be not practical.

[0069]

[Equation 1]

The results are shown in Table 1 below.

[0071]

[Table 1]

As is clear from Table 1, the adhesive of the present invention (Invention 1) has a faster initial tack development time, a higher initial tack strength level, and a higher tack level. The strength can be maintained for a long time. Further, the adhesive of the present invention (Invention 1) has a long sticking holding time and a long sticking time because it maintains good wetting. Furthermore, the adhesive of the present invention (Invention 1) was transferred from an adhesive state to an adhesive state in only one day, the polymer physical properties were not sticky as in Comparative Example 1, and the evaluation of the adhesive physical properties in which the peeling speed was changed was as follows. No change in the adhesive strength as shown in Comparative Example 2 was observed at any of the low speed and the high speed, and the adhesive strength was moderate and the adhesive properties were excellent. In addition, the adhesive of the present invention (Invention 1) was also excellent in the storage stability test.

Example 2 The present invention 1 was processed in the same manner as in Example 1 except that the blending amounts of the components (B) and (C) were changed as shown in Table 2.
~ Each adhesive of the present invention 7 was obtained.

The onset time of the initial adhesion of these seven adhesives,
The initial adhesive strength, the sticking time, the adhesive physical properties and the storage stability were evaluated in the same manner as in Example 1. The results are also shown in Table 2.

[0075]

[Table 2]

As is clear from Table 2, the adhesives of the present invention (Invention 1 to Invention 7) develop initial adhesiveness in a short time in any case, have excellent adhesive strength, and have a possible bonding time. It was sufficient and showed good adhesive properties. Among these, the present invention 1 to the present invention 4 were particularly excellent.

Example 3 In the same apparatus as in Example 1, polyoxypropylene diol (number average molecular weight 2) was used as polyoxyalkylene diol.
000, hydroxyl value 55.8, number of hydroxyl groups per molecule 2, viscosity 300 mPa · s / 25 ° C., trade name: Sumiphen 3600, manufactured by Sumitomo Bayer Urethane Co., Ltd. 1000 parts, and 15 Torr (torr) at 100 ° C. After dehydration for 1 hour, the mixture was cooled to 50 ° C., and an isomer mixture of 4,4′-MDI and 2,4′-MDI as a polyisocyanate (isocyanate content 33.5%, trade name: luplanate MI, BIA) 47.8 made by SFF Japan)
Parts. This NCO / OH ratio was 3.83, and the designed isocyanate content was 8.0%. This polyol and polyisocyanate were reacted at 90 to 95 ° C. for 4 hours and cooled to obtain a prepolymer. This prepolymer has an isocyanate content of 7.80% and a viscosity of 3000 mP.
It was a · s / 25 ° C. This prepolymer is referred to as "prepolymer B".

Invention 8 means that, per 100 parts of prepolymer B, 7 parts of oxazolidine curing agent A as component (B),
An adhesive having a viscosity of 2500 mPa · s / 25 ° C., obtained by blending 2 parts of bis (2,6-morpholinoethyl) ether as the component (C) under a nitrogen stream, stirring for 20 minutes, and homogeneously mixing.

Example 4 In the same apparatus as in Example 1, polyoxypropylene diol (number average molecular weight 2
000, hydroxyl value 55.8, number of hydroxyl groups per molecule 2, viscosity 300 mPa · s / 25 ° C., trade name: Sumifene 3600, manufactured by Sumitomo Bayer Urethane Co., Ltd. 600 parts, hydroxyl-terminated polybutadiene (number average molecular weight 2000, hydroxyl value) 56.0, 2 hydroxyl groups per molecule, viscosity 120
00 mPa · s / 25 ° C., trade name: G-2000, manufactured by Nippon Soda Co., Ltd., 200 parts, and rosin-modified polyol (number average molecular weight 2800, hydroxyl value 54.2, number of hydroxyl groups per molecule 2, viscosity 300 mPa · s / 25 ° C, trade name: K
E615-3, manufactured by Arakawa Chemical Co., Ltd.) was mixed in an amount of 200 parts. The hydroxyl value of this mixed polyol (this mixed polyol is referred to as “mixed polyol a”) was 55.5. This mixed polyol a was added to 15 Torr at 100 ° C.
After dehydration for 1 hour at r), the mixture was cooled to 50 ° C., and 2,4-TDI (isocyanate content rate 48.3%, trade name: Sumidule T-100, manufactured by Sumitomo Bayer Urethane Co.) was used as a polyisocyanate. 2 parts were compounded. This NC
The O / OH ratio is 2.0, and the designed isocyanate content is 3.54%. The mixed polyol a and polyisocyanate are reacted at 90 to 95 ° C. for 4 hours and cooled,
A prepolymer was obtained. This prepolymer has an isocyanate content of 3.45% and a viscosity of 27500 mPa · s / 25.
° C. This prepolymer is referred to as "prepolymer C".

Invention 9 means 1 part of oxazolidine curing agent A as component (B) per 100 parts of prepolymer C,
As a component (C), 2 parts of bis (2,6-morpholinoethyl) ether was blended under a nitrogen stream and stirred for 20 minutes to obtain a homogenous mixture. The viscosity was 25,000 mPa · s / 25 ° C.
Is an adhesive.

Example 5 The same apparatus as in Example 1 was charged with 1000 parts of mixed polyol a, dehydrated at 100 ° C. for 15 hours at 15 torr, and then cooled to 50 ° C. to obtain 4,4 as polyisocyanate. An isomer mixture of'-MDI and 2,4'-MDI (isocyanate content 33.5%, trade name: luplanate MI, manufactured by BSF Japan) was 53.3.
Parts. This NCO / OH ratio is 4.4, and the isocyanate content is 8.01% by design. This mixed polyol a and polyisocyanate were reacted at 90 to 95 ° C. for 4 hours and cooled to obtain a prepolymer. This prepolymer has an isocyanate content of 7.91% and a viscosity of 150.
It was 00 mPa · s / 25 ° C. This prepolymer is referred to as "prepolymer D".

The present invention 10 means that the oxazolidine curing agent A 5 is used as the component (B) per 100 parts of the prepolymer D.
Parts, and 2 parts of bis (2,6-morpholinoethyl) ether as the component (C) were blended under a nitrogen stream and stirred for 20 minutes to obtain a homogeneous mixture, a viscosity of 15000 mPa · s /
It is an adhesive at 25 ° C.

The three types of adhesives obtained in the above Examples 3 to 5 (Invention 8, Invention 9, and Invention 10) exhibited initial tackiness, initial tack strength, laminating time, adhesive physical properties, and The storage stability was evaluated as in Example 1. The results are shown in Table 3.
Shown in

[0084]

[Table 3]

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[Procedure amendment]

[Submission date] July 13, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

That is, as the polyether polyol having an ether bond in the molecule, polyoxyalkylene diols (specifically, polyoxyethylene glycol, polyoxypropylene glycol, polyoxybutylene glycol and the like and copolymers thereof), Polyoxyalkylene polyols such as polyoxyalkylene triols (specifically, those obtained by addition-polymerizing ethylene oxide, propylene oxide, butylene oxide, styrene oxide, etc. with glycerin, trimethylol propane, etc.), other bisphenols, sugars, amines, etc. diols obtained by adding ethylene oxide or propylene oxide as starting material, polyether polyol, polyoxyethylene tetra methylate obtained by ring-opening polymerization of tetrahydrofuran
And glycol.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction content]

The polyisocyanate used in the present invention is a compound having two or more isocyanate groups in one molecule, a so-called polyfunctional isocyanate compound. As such a polyfunctional isocyanate compound, conventionally known compounds can be widely used, and examples thereof include 2,4-toluene diisocyanate (hereinafter referred to as "2,4-TDI") and 2,6-toluene diisocyanate (hereinafter referred to as "2,6- TDI "), an isomer mixture of 2,4-TDI and 2,6-TDI, 4,4'-diphenylmethane diisocyanate (hereinafter referred to as"4,4'-MDI"),2,4'-diphenyl./> Rumeta Nji isocyanate (hereinafter referred to as "2,4'-MDI"
), An isomer mixture of 4,4′-MDI and 2,4′-MDI (trade name: Luplanate MI, manufactured by BSF Japan), carbodiimide-modified MDI, polymethylene polyphenyl polyisocyanate (hereinafter “polymeric MDI”). , Hexamethylene diisocyanate (hereinafter referred to as “HMDI”), xylene diisocyanate (hereinafter referred to as “XDI”), metaxylene diisocyanate, 1,5-naphthalene diisocyanate, hydrogenated MDI, hydrogenated TDI, hydrogenated XDI, isophorone diisocyanate, etc. Isocyanate compounds; Burette polyisocyanate compounds such as Sumidule N (Sumitomo Bayer Urethane Co.); Desmodur IL, HL
(Made by Bayer AG), polyisocyanate compounds having an isocyanate ring such as Coronate EH (made by Nippon Polyurethane Industry Co., Ltd.); Sumidule L (made by Sumitomo Bayer Urethane Co., Ltd.), Coronate HL (made by Nippon Polyurethane Industry Co., Ltd.) ) And other adduct polyisocyanate compounds.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0060

[Correction method] Change

[Correction content]

Invention 1 means bis (N-ethyl-2-isopropyl-1,3-oxazolidine) carbonate (CAS) as component (B) per 100 parts of prepolymer A.
Registration number: 145899-78-1, hereinafter referred to as "oxazolidine curing agent A"), 5 parts, and 2 parts of bis (2,6- dimethylmorpholinoethyl ) ether as component (C) were mixed under a nitrogen stream for 20 minutes. An adhesive having a viscosity of 6800 mPa · s / 25 ° C., which was obtained after stirring and homogeneous mixing. The viscosity at this time was defined as the initial viscosity.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0062

[Correction method] Change

[Correction content]

In Comparative Example 2, 7 parts of only bis (2,6- dimethylmorpholinoethyl ) ether of the component (C) was blended per 100 parts of the prepolymer A, and the viscosity was 6900 mPa. s / 25 ° C adhesive.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0078

[Correction method] Change

[Correction content]

Invention 8 means that, per 100 parts of prepolymer B, 7 parts of oxazolidine curing agent A as component (B),
As a component (C), 2 parts of bis (2,6- dimethylmorpholinoethyl ) ether was blended under a nitrogen stream, stirred for 20 minutes, and obtained after homogeneous mixing. The viscosity was 2500 mPa · s /.
It is an adhesive at 25 ° C.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0080

[Correction method] Change

[Correction content]

Invention 9 means 1 part of oxazolidine curing agent A as component (B) per 100 parts of prepolymer C,
As a component (C), 2 parts of bis (2,6- dimethylmorpholinoethyl ) ether was blended under a nitrogen stream and stirred for 20 minutes to obtain a homogenous mixture. The viscosity was 25,000 mPa · s.
/ 25 ° C adhesive.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0082

[Correction method] Change

[Correction content]

The present invention 10 means that the oxazolidine curing agent A 5 is used as the component (B) per 100 parts of the prepolymer D.
Part, and 2 parts of bis (2,6- dimethylmorpholinoethyl ) ether as the component (C) were blended under a nitrogen stream and stirred for 20 minutes to obtain a homogeneous mixture having a viscosity of 15,000 mPas.
-S / 25 ° C adhesive.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area C08G 18/32 NDT C08G 18/32 NDT

Claims (8)

[Claims] 1. An isocyanate-terminated urethane prepolymer comprising (A) a polyol and a polyisocyanate,
A one-component elastic moisture-curable liquid urethane adhesive containing (B) a compound having two or more oxazolidine rings in the molecule and (C) bis (morpholinoethyl) ethers. 2. An isocyanate-terminated urethane prepolymer 1 comprising (A) a polyol and a polyisocyanate.
0.1 to 30 parts by weight of a compound having two or more oxazolidine rings in the molecule (B) and 0.1 to 10 parts by weight of (C) bis (morpholinoethyl) ether per 100 parts by weight. The adhesive according to claim 1, wherein 3. A condensation type polyester polyol obtained by the condensation reaction of a polyhydric alcohol and a polycarboxylic acid, wherein the polyol (A) is a hydroxyl group-terminated polybutadiene,
The adhesive according to claim 1, which is at least one selected from a rosin-modified polyol having a rosin skeleton in the molecule, a polyol having an amine structure in the molecule, and a polyoxyalkylene polyol. 4. The polyhydric alcohol constituting the condensed polyether polyol is at least one selected from polyoxyalkylene diol, polyoxyalkylene triol, diethylene glycol, hexyl glycol and neopentyl glycol, and the polyvalent carboxylic acid is The adhesive according to claim 3, which is at least one selected from adipic acid, sebacic acid, isophthalic acid, and trimellitic acid. 5. The adhesive according to claim 1, wherein the polyisocyanate as the component (A) is an aromatic polyisocyanate. 6. The aromatic polyisocyanate is 4,4′-
The at least one selected from diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, 2,4-toluene diisocyanate and 2,6-toluene diisocyanate. adhesive. 7. The adhesive according to claim 1, wherein the compound having two or more oxazolidine rings in the molecule of the component (B) is bis (N-ethyl-2-alkyl-1,3-oxazolidine) carbonate. 8. A bis (morpholinoethyl) component (C).
The adhesive according to claim 1, wherein the ethers are at least one selected from bis (morpholinoethyl) ether, bis (2,6-dimethylmorpholinoethyl) ether and bis (3,5-dimethylmorpholinoethyl) ether.