JP2022011881A - Method for Producing Polyisocyanate Composition - Google Patents

Abstract

To provide: a polyisocyanate composition, comprising an isocyanate group-containing polymer (A) which is a reaction product of an aromatic polyisocyanate (a1) and a polyether polyol (a2), the composition containing a reduced amount of free aromatic isocyanate monomer; and an adhesive composition comprising the composition, which contains a reduced amount of free aromatic isocyanate monomer, has excellent initial cohesive strength and adhesive strength, further contains a reduced amount of residual solvent, and has excellent slipperiness during processing.SOLUTION: Provided is a method for producing a polyisocyanate composition, comprising reacting a polyisocyanate containing an aromatic polyisocyanate (a1) and a polyol comprising the polyether polyol (a2) in a molar equivalent ratio (number of moles of isocyanate groups/number of moles of hydroxyl groups) in a range of 1.1 to 1.5.SELECTED DRAWING: None

Description

The present invention comprises a method for producing a polyisocyanate composition containing an isocyanate group-containing polymer useful for an adhesive composition used for packaging materials for foods, medical products, cosmetics, etc., and an isocyanate group-containing produced by the production method. The present invention relates to a method for producing an adhesive composition and a laminate using a polyisocyanate composition containing a polymer.

Conventionally, as a food packaging or industrial adhesive, a polyurethane-based adhesive in which a polyol component such as a polyester polyol or a polyether urethane polyol and a polyisocyanate composition are combined has been used. The polyisocyanate composition includes a polyether polyol such as polyoxypropylene glycol (PPG) or polytetramethylene ether glycol (PTMG), and 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate or tolylene diisocyanate. It is known to use a prepolymer obtained by reacting with an aromatic diisocyanate such as the above with urethane.
However, unreacted aromatic diisocyanate remains in the prepolymer, which may affect the initial cohesive force of the adhesive, hygiene during processing, generation of primary aromatic amine, residual solvent, and the like. ..

Regarding a method for reducing the residual amount of aromatic diisocyanate, for example, Patent Document 1 describes unreacted diphenylmethane diisocyanate (hereinafter referred to as MDI) from a prepolymer obtained by a urethane reaction between an aromatic diisocyanate and a polyol using a distillation method. ) Is disclosed.

Patent Document 2 describes diphenylmethane diisocyanate and a linear molecule having a weight average molecular weight (Mw) of 250 to 4,000 and two active hydrogens, and having a molar equivalent ratio (NCO: OH) of 2.5 to 10 :. It is disclosed that after the reaction in the range of 1, the free diphenylmethane diisocyanate is vacuum-distilled to 1% by mass or less.

Patent Document 3 describes that the residual amount of diisocyanate in the polyurethane prepolymer reaction product is reduced by performing distillation under a mixed solvent of a solvent having a boiling point higher than that of the residual diisocyanate and a solvent having a boiling point lower than that of the residual diisocyanate. The process of making it is disclosed.

Japanese Patent No. 381320 Japanese Unexamined Patent Publication No. 8-176252 U.S. Pat. No. 5,703,193

However, in all of Patent Documents 1 to 3, the aromatic diisocyanate remaining in the urethanization reaction is removed by using a distillation step, and the free aromatic diisocyanate (free aromatic diisocyanate) is removed in the reaction stage without going through the distillation step. Hereinafter, a method for reducing (hereinafter referred to as residual isocyanate monomer) has not yet been realized.
Therefore, an object of the present invention is a polyisocyanate containing an isocyanate group-containing polymer (A) which is a reaction product of an aromatic polyisocyanate (a1) and a polyether polyol (a2) in which free aromatic diisocyanate is reduced. The composition and the adhesive composition using the composition have reduced free aromatic diisocyanates, excellent initial cohesive strength and adhesive strength, reduced residual solvent, and excellent slipperiness during processing. And to provide a laminate.

The present invention relates to a method for producing a polyisocyanate composition containing an isocyanate group-containing polymer (A) which is a reaction product of an aromatic polyisocyanate (a1) and a polyether polyol (a2). ) And the polyol containing the polyether polyol (a2), the molar equivalent ratio of the isocyanate group in the polyisocyanate to the hydroxyl group in the polyol (the number of moles of the isocyanate group / the number of moles of the hydroxyl group) is 1. The present invention relates to a method for producing a polyisocyanate composition, which comprises reacting in the range of 1 to 1.5.

The present invention relates to a method for producing the polyisocyanate composition, wherein the aromatic polyisocyanate (a1) is diphenylmethane diisocyanate or a derivative thereof.

The present invention relates to a method for producing the polyisocyanate composition, wherein the polyether polyol (a2) is polypropylene glycol.

The present invention relates to a method for producing the above polyisocyanate composition, wherein the content of diphenylmethane diisocyanate or a derivative thereof in the polyisocyanate composition is 1% by mass or less.

The present invention relates to a method for producing an adhesive composition, which comprises a step of mixing the polyisocyanate composition produced by the above method with the polyol component (B).

The present invention relates to a method for producing the adhesive composition, wherein the adhesive composition is a laminated adhesive for forming a packaging material.

In the present invention, the adhesive composition produced by the above method is applied to a first sheet-like substrate to form an adhesive layer, and the second sheet-like substrate is superposed on the adhesive layer. The present invention relates to a method for producing a laminate, which comprises a step of curing an adhesive layer.

INDUSTRIAL APPLICABILITY According to the present invention, a polyisocyanate composition containing an isocyanate group-containing polymer (A), which is a reaction product of an aromatic polyisocyanate (a1) and a polyether polyol (a2), in which free aromatic diisocyanates are reduced, and a polyisocyanate composition. Provided are an adhesive composition and a laminate in which free aromatic diisocyanates containing the composition are reduced, initial cohesive strength and adhesive strength are excellent, residual solvent is reduced, and slipperiness during processing is excellent. be able to.

<Polyisocyanate composition>
The present invention relates to a method for producing a polyisocyanate composition containing an isocyanate group-containing polymer (A) which is a reaction product of an aromatic polyisocyanate (a1) and a polyether polyol (a2). The molar equivalent ratio of the polyisocyanate containing (a1) and the polyol containing the polyether polyol (a2) to the isocyanate group in the polyisocyanate and the hydroxyl group in the polyol (number of moles of isocyanate group / number of moles of hydroxyl group). ) Is reacted in the range of 1.1 to 1.5. Such an isocyanate group-containing polymer (A) is suitably used as a polyisocyanate curing agent in urethane-based adhesives.
By reacting at the above molar equivalent ratio, the residual amount of free aromatic polyisocyanate (a1) (hereinafter, also referred to as residual monomer) is 1% by mass or less while suppressing gelation without requiring a distillation step. The polyisocyanate composition is obtained, and can be suitably used as a curing agent for a urethane-based adhesive composition in combination with a polyol component (main agent).
Hereinafter, the present invention will be described in detail.

[Aromatic polyisocyanate (a1)]
Examples of the aromatic polyisocyanate (a1) include aromatic diisocyanates such as diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, phenylenediocyanate, tolylene diisocyanate, and naphthalene diisocyanate; or derivatives or composites thereof.
The aromatic polyisocyanate (a1) is preferably diphenylmethane diisocyanate or a derivative thereof, for example, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, Alternatively, polymethylene polyphenyl polyisocyanate can be mentioned.
More preferably, it is 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, or polymethylenepolyphenylpolyisocyanate, and even more preferably, 4,4'-diphenylmethane diisocyanate, or 2,4'-diphenylmethane diisocyanate. Is included.
One of these aromatic polyisocyanates (a1) may be used alone, or two or more thereof may be used in combination.

[Polyether polyol (a2)]
Examples of the polyether polyol (a2) include polyether diols, polyether triols and the like, and examples thereof include oxylane compounds such as ethylene oxide, propylene oxide, butylene oxide and tetrahydrofuran, and bifunctional lows such as water, ethylene glycol and propylene glycol. Polyether diol obtained by polymerizing with a quantity polyol as an initiator; a poly obtained by polymerizing an oxylan compound such as ethylene oxide, propylene oxide, butylene oxide, or tetrahydrofuran with a low-quantity triol such as trimethylolpropane or glycerin as an initiator. Ethertriol; The above-mentioned polyether polyol may be a polyether urethane polyol further reacted with diisocyanate.
The polyether polyol (a2) is preferably a bifunctional polypropylene glycol (hereinafter, also referred to as PPG), more preferably a polypropylene glycol having a number average molecular weight of 200 to 8,000, and further preferably a number average. It is polypropylene glycol having a molecular weight of 400 to 4,000.
These polyether polyols (a2) may be used alone or in combination of two or more. From the viewpoint of the initial viscosity after mixing with the polyol component, it is preferable to use polypropylene glycol having a number average molecular weight of 200 to 1,000 and polypropylene glycol having a number average molecular weight of 1,500 to 4,000 in combination.

[Urethane reaction conditions]
In the present invention, a polyisocyanate containing an aromatic polyisocyanate (a1) and a polyol containing a polyether polyol (a2) have a molar equivalent ratio of an isocyanate group in the polyisocyanate and a hydroxyl group in the polyol (isocyanate group). It is important to react in the range of 1.1 to 1.5 (number of moles / number of moles of hydroxyl group), and by setting this range, polyisocyanate and polyol react efficiently without gelation. As a result, the residual amount of aromatic polyisocyanate (a1) can be reduced, the molecular weight and the number of urethane crosslinks are increased, and when combined with a polyol component to form a coating composition, the residual solvent is reduced, which is excellent. It can exhibit initial cohesive force, adhesive performance, and slipperiness. The molar equivalent ratio is preferably in the range of 1.1 to 1.4, more preferably in the range of 1.2 to 1.3.

The residual amount of aromatic diisocyanate (a1) such as free aromatic diisocyanate in the polyisocyanate composition of the present invention can be measured by a method known to those skilled in the art, for example, high performance liquid chromatography (HPLC). The content of the free aromatic polyisocyanate (a1) in the polyisocyanate composition is preferably 1% by mass or less, more preferably 0.5% by mass or less. Therefore, when the aromatic polyisocyanate (a1) is diphenylmethane diisocyanate or a derivative thereof, the content of diphenylmethane diisocyanate or its derivative in the polyisocyanate composition is preferably 1% by mass or less, more preferably 0. It is 5% by mass or less.

The reaction temperature of the urethane reaction is preferably in the range of 80 to 100 ° C. By setting the reaction temperature within the above range, excessive heat generation and runaway reaction can be prevented. The urethane reaction may be carried out without a solvent, or any solvent inert to the isocyanate group may be used. Further, if necessary, a catalyst for promoting the urethane reaction may be used.

The polyisocyanate may contain a polyisocyanate other than the aromatic polyisocyanate (a1), and as such a polyisocyanate, the description of the polyisocyanate in the section of the adhesive composition described later can be incorporated.

Further, the polyol may contain a polyol other than the polyether polyol (a2), and as such a polyol, the description of the polyol component (B) in the section of the adhesive composition described later can be incorporated.

The isocyanate group content in the polyisocyanate composition is preferably 1 to 10% by mass, more preferably 1 to 10% by mass, because the viscosity after blending with the polyol (B) described later is in a range suitable for coating. It is 1 to 5% by mass.
The number average molecular weight of the polyisocyanate composition is preferably 1,000 to 5,000 because the initial viscosity does not become too high, and the viscosity of the polyisocyanate composition at 25 ° C. is preferably 5,000 mPa · s or less. It is more preferably 3,000 mPa · s or less.

<Adhesive composition>
The adhesive composition of the present invention can be obtained by mixing the polyisocyanate composition containing the isocyanate group-containing polymer (A) with the polyol component (B).

[Polyform component (B)]
The polyol component (B) may be any compound having two or more hydroxyl groups, and can be selected from known polyols.
Examples of the polyol component (B) include polyester polyols, polyether polyols, polyurethane polyols, polyesteramide polyols, acrylic polyols, polycarbonate polyols, polycaprolactone polyols, polyvalerolactone polyols, polyolefin polyols, polyhydroxyalkanes, castor oil or theirs. Besides the mixture
Ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-5-pentanediol, 1,6-hexanediol, neopentyl glycol, methylpentane glycol , Triethylene glycol, tetraethylene glycol, dipropylene glycol, bishydroxyethoxybenzene, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, triethylene glycol and other glycols; polys with a number average molecular weight of 200 to 3,000. An alkylene glycol; a trifunctional or tetrafunctional aliphatic alcohol such as glycerin, trimethylolpropane, or pentaerythritol; a polyol obtained by adding the glycol or a polyol to the above trifunctional or tetrafunctional aliphatic alcohol; can be used.

The polyol component (B) may be an acid-modified product in which a part of the hydroxyl group in the polyol is acid-modified, a product in which a carboxyl group is introduced by reacting with an acid anhydride, or a urethane by reacting with a diisocyanate. It may be one in which a bond is introduced.
One of these polyol components may be used alone, or two or more thereof may be used in combination.

The polyol component (B) preferably contains a polyester polyol or a polyether polyol from the viewpoint of adhesive performance and residual solvent.

(Polyester polyol)
Examples of polyester polyols include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, phthalic anhydride, adipic acid, azelaic acid, sebacic acid, succinic acid, glutaric acid, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, maleic anhydride, and anhydrous. Dibasic acids such as itaconic acid or dialkyl esters thereof or mixtures thereof (hereinafter, also referred to as carboxyl group components), ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, butylene glycol, neopentyl glycol, Gineopentyl glycol, trimethylolpropane, glycerin, 1,6-hexanediol, 1,4-butanediol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, 3,3'-di Diols such as methylol heptane, 1,9-nonanediol, polyoxyethylene glycol, polyoxypropylene glycol, polytetramethylene ether glycol, polyether polyol, polycarbonate polyol, polyolefin polyol, acrylic polyol, polyurethane polyol, etc. or mixtures thereof ( Hereinafter, it is also referred to as a hydroxyl group component) and a polyester polyol obtained by an esterification reaction; or lactones such as polycaprolactone, polyvalerolactone, and poly (β-methyl-γ-valerolactone) are ring-open polymerized. The resulting polyester polyol; may be mentioned.
Two or more kinds of the above-mentioned carboxyl group component and hydroxyl group component may be used in combination.

The polyester polyol may be a polyester polyurethane polyol further reacted with diisocyanate, or may be further reacted with an acid anhydride.
Examples of the diisocyanate include 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, 1,5-naphthalenedi isocyanate, hexamethylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Will be.
Examples of the acid anhydride include pyromellitic anhydride, melitric anhydride, trimellitic anhydride, and trimellitic acid ester anhydride. Examples of the trimellitic acid ester anhydride include ethylene glycol bisamhydrotrimellitic acid and propylene glycol bisamhydrotrimellitic acid.

The number average molecular weight of the polyester polyol is preferably 1,000 to 10,000, more preferably 1,500 to 5,000. When the number average molecular weight is 1,000 or more, the cohesive force of the polyol is increased and excellent adhesive strength is exhibited, which is preferable. When the number average molecular weight is 10,000 or less, the increase in viscosity after mixing with the curing agent becomes gradual, and the coatability does not deteriorate, which is preferable.
The number average molecular weight in the present specification can be determined as a standard polystyrene-equivalent value using, for example, GPC (gel permeation chromatography) "Shodex GPCSystem-21" manufactured by Showa Denko KK and Tetrohydrofuran as a solvent. ..
When the polyester polyol contains a plurality of polyester polyols, the number average molecular weight of each polyester polyol can be obtained from the number average molecular weight of each polyester polyol and its mass ratio.

(Polyether polyol)
Examples of the polyether polyol include those obtained by polymerizing an oxylan compound such as ethylene oxide, propylene oxide, butylene oxide and tetrahydrofuran using a bifunctional low molecular weight polyol such as ethylene glycol and propylene glycol as an initiator. The above-mentioned polyether polyol may be a polyether polyurethane polyol further reacted with diisocyanate.

The number average molecular weight of the polyether polyol is preferably 400 or more and 4,000 or less, and more preferably 400 or more and 2,000 or less.

The acid value of the polyol component (B) is preferably 0 to 10 mgKOH / g, and the hydroxyl value of the polyol component (B) is preferably 0 to 100 mgKOH / g. When the polyol component (B) contains a plurality of polyols, the acid value and hydroxyl value of the polyol component (B) can be obtained from the acid value and hydroxyl group of each polyol and their mass ratio.
One of these polyol components (B) may be used alone, or two or more thereof may be used in combination.

[Other polyisocyanates]
The adhesive composition in the present invention may contain a polyisocyanate other than the isocyanate group-containing polymer (A) as the polyisocyanate composition as long as the effects of the present invention are not impaired. The content of the isocyanate group-containing polymer (A) in the polyisocyanate composition is preferably in the range of 50 to 95% by mass, more preferably in the range of 60 to 80% by mass, based on the polyisocyanate composition. Is.

Other polyisocyanates that may be included can be selected from known polyisocyanates, for example, aromatic polyisocyanates, aromatic aliphatic polyisocyanates, aliphatic polyisocyanates, alicyclic polyisocyanates, or modified products thereof. Can be mentioned.
These other polyisocyanates may be used alone or in combination of two or more.

Examples of the aromatic polyisocyanate include aromatic diisocyanates such as diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, phenylenediocyanate, tolylene diisocyanate, and naphthalene diisocyanate; and aromatic polyisocyanates such as polymethylene polyphenyl polyisocyanate. ..
Examples of the aromatic aliphatic polyisocyanate include 1,3- or 1,4-xylylene diisocyanate or a mixture thereof, ω, ω'-diisocyanate-1,4-diethylbenzene, 1,3- or 1,4-bis (1,3- or 1,4-bis). 1-Isocyanate-1-methylethyl) Aromatic aliphatic diisocyanates such as benzene or a mixture thereof;
Examples of the aliphatic polyisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, 1,2-propylene diisocyanis, 1,2-butyrenized isocyanate, 2,3-butyrenis diisocyanate, 1,3-butyrenis diisocyanate, and 2). , 4,4- or 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisamethylene methyl caproate, lysine diisocyanis, aliphatic diisocyanates such as dimerate diisocyanate;
Examples of the alicyclic polyisocyanate include 1,4-cyclohexanediisocyanate, 1,3-cyclohexanediisocyanate, isophorone diisocyanate, 4,4'-methylenebis (cyclohexylisocyanate), methyl2,4-cyclohexanediisocyanate, and methyl2,6. -Alicyclic diisocyanates such as cyclohexanediisocyanate, 1,4-bis (isocyanatemethyl) cyclohexane, 1,3-bis (isocyanatemethyl) cyclohexane, norbornendiisocyanate; can be mentioned.

Examples of the modified polyisocyanate include an allophanate-type modified product, an isocyanurate-type modified product, a biuret-type modified product, and an adduct-type modified product, and the above-mentioned polyisocyanate composition and a polyol are reacted under a condition of excess isocyanate group. Examples thereof include reaction products having an isocyanate group and a urethane bond. The polyol forming the modified product of the polyisocyanate is not particularly limited and can be selected from known polyols, for example, polyester polyol, polyester urethane polyol, polycarbonate polyol, polycaprolactone polyol, polyether polyol, polyether. Examples thereof include urethane polyols, polyolefin polyols, acrylic polyols, silicone polyols, castor oil-based polyols, and fluoropolyesters.

The blending ratio of the polyisocyanate composition containing the isocyanate group-containing polymer (A) and the polyol component (B) is the molar of all the isocyanate groups contained in the polyisocyanate composition and all the hydroxyl groups contained in the polyol (B). The equivalent ratio [NCO / OH] is preferably in the range of 2.0 to 7.0, more preferably in the range of 4.0 to 6.0. The blending amount of the polyisocyanate composition is preferably 30 to 70% by mass, more preferably 35 to 50% by mass, based on the polyol (B) from the viewpoint of adhesive performance.

[Other ingredients]
The adhesive composition in the present invention is a polyisocyanate composition containing an isocyanate group-containing polymer (A) and other components other than the polyol component (B) in order to satisfy various physical properties required for the adhesive composition or packaging material. May be contained. These other components may be added to either the polyisocyanate composition or the polyol component (B), or may be added when the polyisocyanate composition and the polyol component (B) are mixed. These other components may be used alone or in combination of two or more.

(Silane coupling agent)
The adhesive composition in the present invention may further contain a silane coupling agent in order to enhance the adhesion to the substrate. Examples of the silane coupling agent include trialkoxysilanes having vinyl such as vinyltrimethoxysilane and vinyltriethoxysilane; 3-aminopropyltriethoxysilane and N- (2-aminoethyl) 3-glycidoxypropyltri. Trialkoxysilanes having a glycidyl group such as methoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltriexitosisilane; 3-isocyanuspropyltrimethoxysilane, 3-isocyanuppropyltri Examples thereof include trialkoxysilanes having an isocyanate group such as ethoxysilane; alkoxysilanes having a mercapto group such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and organosilanes. The silane coupling agent may be used alone or in combination of two.
The content of the silane coupling agent is preferably 0.1 to 10% by mass, more preferably 0.1 to 5% by mass, and particularly preferably 0.5 to 5% by mass with respect to the solid content of the polyol component. %.

(Phosphoric acid, phosphoric acid epoxy, phosphorus oxygen acid or its derivative)
The adhesive composition in the present invention may further contain phosphoric acid, phosphoric acid epoxy, an oxygen acid of phosphorus or a derivative thereof in order to enhance the adhesive performance. Examples of the phosphoric acid epoxy include URAD-DD79 manufactured by DSM Resin Resin Co., Ltd. The content of the phosphoric acid epoxy is preferably 0.01 to 10% by mass, more preferably 0.1 to 1% by mass, based on the solid content of the adhesive.
Among the oxygen acids of phosphorus or derivatives thereof, the oxygen acid of phosphorus may be any one having at least one free oxygen acid, for example, hypophosphoric acid, phosphoric acid, orthophosphoric acid, the following. Examples thereof include phosphoric acids such as phosphoric acid, and condensed phosphoric acids such as metaphosphoric acid, pyrophosphoric acid, tripolyphosphoric acid, polyphosphoric acid, and ultraphosphoric acid.
Examples of the derivative of the oxygen acid of phosphorus include those obtained by partially esterifying the oxygen acid of phosphorus with alcohols in a state where at least one free oxygen acid is left. Examples of these alcohols include fatty alcohols such as methanol, ethanol, ethylene glycol and glycerin; aromatic alcohols such as phenol, xylenol, hydroquinone, catechol and fluoroglycinol; and the like. Oxygen acid of phosphorus or a derivative thereof may be used in combination of two or more. The content of oxygen acid or a derivative thereof of phosphorus is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, still more preferably 0.1 to 1 with respect to the solid content of the adhesive. It is mass%.

(Leveling agent or antifoaming agent)
The adhesive composition in the present invention may further contain a leveling agent or an antifoaming agent in order to improve the appearance of the laminate. Examples of the leveling agent include polyether-modified polydimethylsiloxane, polyester-modified polydimethylsiloxane, aralkyl-modified polymethylalkylsiloxane, polyester-modified hydroxyl group-containing polydimethylsiloxane, polyether ester-modified hydroxyl group-containing polydimethylsiloxane, and acrylic copolymer. , Methacrylic copolymers, polyether-modified polymethylalkylsiloxanes, acrylic acid alkyl ester copolymers, methacrylic acid alkyl ester copolymers, and lecithin.
Examples of the defoaming agent include a silicone resin, a silicone solution, and a copolymer of an alkyl vinyl ether, an acrylic acid alkyl ester, and a methacrylic acid alkyl ester.

(Reaction accelerator)
Since the adhesive composition in the present invention promotes the urethanization reaction, it can further contain a reaction accelerator. Examples of the reaction accelerator include metal-based catalysts such as dibutyltin diacetate, dibutyltin dilaurate, dioctyltin dilaurate, and dibutyltin dimarate; 1,8-diaza-bicyclo (5,4,0) undecene-7,1, Tertiary amines such as 5-diazabicyclo (4,3,0) nonen-5,6-dibutylamino-1,8-diazabicyclo (5,4,0) undecene-7; reactive tertiary amines such as triethanolamine. Amine;

(Stabilizer)
The adhesive composition in the present invention can further contain a stabilizer in order to stabilize the urethanization reaction and maintain stability over time during storage. Examples of the stabilizer include benzoyl chloride, propylene oxide, 1,2-butylene oxide, trimethyl orthostate, ethyl orthostate, -n-propyl orthostate, methyl orthoacetate, and ethyl orthoacetate.

(Additive)
The adhesive composition may contain various additives as long as the effects of the present invention are not impaired. Examples of the additive include inorganic fillers such as silica, alumina, mica, talc, aluminum flakes, and glass flakes, layered inorganic compounds, stabilizers (antioxidants, heat stabilizers, ultraviolet absorbers, hydrolysis inhibitors, etc.). ), Anti-rust agents, thickeners, plasticizers, antistatic agents, lubricants, anti-blocking agents, colorants, fillers, crystal nucleating agents, catalysts for adjusting the curing reaction.

<Laminated body>
The above-mentioned adhesive composition is applied to a first sheet-like substrate to form an adhesive layer, and a second sheet-like substrate is superposed on the adhesive layer, and between the two sheet-like substrates. By curing the located adhesive layer, the laminate of the present invention can be obtained. However, the structure of the laminated body is not limited to the above structure, and another layer may be further laminated via an adhesive layer or the like. The thickness of the laminate is preferably 10 μm or more from the viewpoint of strength and durability as a packaging material.

[Adhesive layer]
The adhesive layer is generally formed by applying an adhesive to one side of a first sheet-like substrate using a laminator to form an uncured adhesive layer, and then forming a coated surface and a second sheet-like substrate. It can be formed by laminating and curing at room temperature or heating. The amount of the adhesive applied is preferably about 1 to 5 g / m ² .

[Sheet-like base material]
The sheet-shaped base material is not particularly limited, and examples thereof include conventionally known plastic films, papers, and metal foils, and the two sheet-shaped base materials may be of the same type or different types.
As the plastic film, a film of a thermoplastic resin or a thermosetting resin can be used, and a film of a thermoplastic resin is preferable. Examples of the thermoplastic resin include polyolefins, polyesters, polyamides, polystyrenes, vinyl chloride resins, vinyl acetate resins, ABS resins, acrylic resins, acetal resins, polycarbonate resins, and fibrous plastics. The sheet-like base material may be provided with a barrier film such as a thin-film deposition layer, and examples of the vapor-deposited layer include a thin-film deposition layer such as aluminum, silica, and alumina.

The first sheet-like substrate is preferably a plastic film. Examples of the plastic film include those commonly used for packaging materials, and polyester resin films such as polyethylene terephthalate, polyethylene naphthalate (PEN), and polylactic acid (PLA); polyethylene (PE), polypropylene (PP). Polyolefin resin film such as; Polystyrene resin film; Nylon 6, Poly-p-xylylene adipamide (MXD6 nylon) such as Polyamide resin film; Polycarbonate resin film; Polyacrylic nitrile resin film; Polyimide resin film; Examples thereof include a multilayer film (for example, nylon 6 / MXD6 / nylon 6, nylon 6 / ethylene-vinyl alcohol copolymer / nylon 6) and a mixture. Among them, those having mechanical strength and dimensional stability are preferable.
The plastic film preferably has a thickness of 5 μm or more and 50 μm or less, and more preferably 10 μm or more and 30 μm or less.

When the second sheet-like base material is the outermost layer of the laminate, it is preferable that the second sheet-like base material is a sealant base material.
Examples of the sealant base material include low-density polyethylene (LDPE), polyethylene such as linear low-density polyethylene (LLDPE) and high-density polyethylene (HDPE), acid-modified polyethylene, unstretched polypropylene (CPP), and acid-modified polypropylene. Examples thereof include polyethylene copolymer, ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid ester copolymer, polyethylene- (meth) acrylic acid copolymer, and ionomer.
The thickness of the sealant base material is not particularly limited, and is preferably 10 to 150 μm, more preferably 20 to 70 μm, in consideration of processability to the packaging material, heat sealability, and the like. Further, by providing the sealant base material with irregularities having a height difference of about several μm, slipperiness and tearability of the packaging material can be imparted.
When the second sheet-like base material serves as an intermediate layer of the laminated body, the above-mentioned plastic film, paper, metal foil, or the like can be preferably used as the second sheet-like base material.

The sheet-like base material may have a printing layer on the base material. The print layer includes letters, numbers, patterns, figures, symbols, patterns, etc. for decoration, display of contents, display of expiration date, display of manufacturers, sellers, etc., and for the purpose of displaying other things and giving a sense of beauty. A layer that forms any desired print pattern, including a solid print layer. The print layer can be formed by using a conventionally known pigment or dye, and the method for forming the print layer is not particularly limited.

Generally, the printing layer is formed by using a printing ink containing a colorant such as a pigment or a dye. The method of applying the printing ink is not particularly limited, and the printing ink can be applied by a method such as a gravure coating method, a flexographic coating method, a roll coating method, a bar coating method, a die coating method, a curtain coating method, a spin coating method, and an inkjet method. .. The printed layer can be formed by leaving it as it is or, if necessary, by blowing air, heating, drying under reduced pressure, irradiating with ultraviolet rays, or the like.
The printed layer preferably has a thickness of 0.1 to 10 μm, more preferably 1 to 5 μm, and even more preferably 1 to 3 μm.

An example of the structure of the laminated body in the present invention is given below, but the present invention is not limited thereto.
Biaxially stretched polypropylene (hereinafter, OPP) / printing layer / adhesive layer / unstretched polypropylene (hereinafter, CPP),
OPP / printing layer / adhesive layer / AL vapor deposition CPP,
OPP / printing layer / adhesive layer / PE,
Print layer / OPP / Adhesive layer / CPP,
NY / printing layer / adhesive layer / PE,
Print layer / NY / Adhesive layer / CPP
NY / Print layer / Adhesive layer / CPP,
PET / printing layer / adhesive layer / CPP,
Print layer / PET / Adhesive layer / CPP
PET / printing layer / adhesive layer / NY / adhesive layer / CPP,
Transparent vapor deposition PET / printing layer / adhesive layer / NY / adhesive layer / CPP,
PET / printing layer / adhesive layer / AL vapor deposition PET / adhesive layer / PE,
PET / printing layer / adhesive layer / AL / adhesive layer / CPP,
PET / printing layer / adhesive layer / AL / adhesive layer / PE,
PET / printing layer / adhesive layer / NY / adhesive layer / AL / adhesive layer / CPP,
PET / printing layer / adhesive layer / AL / adhesive layer / NY / adhesive layer / CPP

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. Unless otherwise specified, "parts" and "%" in Examples and Comparative Examples mean "parts by mass" and "% by mass".

<Measurement method of number average molecular weight (Mn)>
The number average molecular weight (Mn) was measured by using GPC (Gel Permeation Chromatography) "Shodex GPC System-21" manufactured by Showa Denko KK. GPC is a liquid chromatography in which substances dissolved in a solvent are separated and quantified according to the difference in their molecular sizes. The solvent is tetrohydrofuran, and the molecular weight is determined in terms of polystyrene.

<Measurement method of acid value>
Approximately 1 g of the sample was precisely weighed in a stoppered Erlenmeyer flask, and 100 ml of a toluene / ethanol (volume ratio: toluene / ethanol = 2/1) mixed solution was added and dissolved. Phenolphthalein test solution was added to this as an indicator and lasted for 30 seconds. Then, it was titrated with 0.1N alcoholic potassium hydroxide solution until the solution became pink. The acid value was determined by the following (Equation 1).
(Equation 1) Acid value (mgKOH / g) = [{(ba) × F × 28.25} / S]
However, S: sample collection amount (g)
a: Consumption of 0.1N alcoholic potassium hydroxide solution (ml)
b: Consumption (ml) of 0.1N alcoholic potassium hydroxide solution in the blank experiment
F: Potency of 0.1N alcoholic potassium hydroxide solution

<Measurement method of hydroxyl value>
Approximately 1 g of the sample was precisely weighed in a stoppered Erlenmeyer flask, and 100 ml of a toluene / ethanol (volume ratio: toluene / ethanol = 2/1) mixed solution was added and dissolved. Further, exactly 5 ml of an acetylating agent (a solution in which 25 g of acetic anhydride was dissolved in pyridine to make a volume of 100 ml) was added, and the mixture was stirred for about 1 hour. Phenolphthalein test solution is added to this as an indicator and lasts for 30 seconds. Then, it was titrated with 0.1N alcoholic potassium hydroxide solution until the solution became pink. The hydroxyl value was determined by the following (Equation 2). The hydroxyl value was taken as the value of the dry state of the resin.
(Equation 2) Hydroxy group value (mgKOH / g) = [{(ba) × F × 28.25} / S] / (nonvolatile content concentration / 100) + D
However, S: sample collection amount (g)
a: Consumption of 0.1N alcoholic potassium hydroxide solution (ml)
b: Consumption (ml) of 0.1N alcoholic potassium hydroxide solution in the blank experiment
F: Potency of 0.1N alcoholic potassium hydroxide solution
D: Acid value (mgKOH / g)

<Measurement method of NCO content (% by mass)>
About 1 g of the sample was weighed in a 200 mL Erlenmeyer flask, and 10 mL of a toluene solution of 0.5 N-n-butylamine and 10 mL of toluene were added and dissolved. Next, a phenolphthalein test solution was added as an indicator, held for 30 seconds, and then titrated with a 0.25N hydrochloric acid solution until the solution turned pink. The NCO content (% by mass) was determined by the following (Equation 3).
(Equation 3): NCO (mass%) = {(ba) × 4.202 × F × 0.25} / S
However, S: sample collection amount (g)
a: Consumption of 0.25N hydrochloric acid solution (ml)
b: Consumption (ml) of 0.25N hydrochloric acid solution in the blank experiment
F: Titer of 0.25N hydrochloric acid solution

<Measuring method of residual amount of aromatic polyisocyanate (a1)>
The residual amount of aromatic polyisocyanate (a1) was calculated using a high performance liquid chromatograph (HIGH PERFORMANCE LIQUID CHROMATOGRAPH) "Shimadzu HPLC Practice" manufactured by Shimadzu Corporation. Specifically, after diluting about 25 mg of the sample 25,000 times and performing the derivative treatment, the peak area derived from the residual aromatic polyisocyanate (a1) is measured by a high performance liquid chromatograph, and the peak area is measured in the sample. The residual amount of was calculated. The measurement conditions are shown below.
Column: GL Science ODS-3 (250 mm x 2.1 mmφ, particle diameter 5 μm)
Detector: Shimadzu UFLC 20A series PDA detector Mobile phase: Triethylamine 3% aqueous solution / acetonitrile = 20/80% by volume (adjusted to PH3.0 with phosphoric acid) Isocratic, flow velocity: 0.2 ml / min

<Manufacturing of polyisocyanate composition>
[Example 1] Polyisocyanate composition 1
In a reaction vessel equipped with a stirrer, a thermometer, a reflux cooling tube, a dropping tank and a nitrogen gas input tube, 25 parts of bifunctional polypropylene glycol having a number average molecular weight of 2,000 and 19 parts of bifunctional polypropylene glycol having a number average molecular weight of 400, Two parts of trimethylolpropane, one part of dipropylene glycol, and one part of tripropylene glycol were charged. While introducing nitrogen gas, 25 parts of 4,4-diphenylmethane diisocyanate was charged into a reaction vessel while stirring, and heated at 80 ° C. to 90 ° C. for 5 hours to carry out a urethanization reaction, and the isocyanate group-containing polymer (A-1) was subjected to a urethanization reaction. Got The molar equivalent ratio of the isocyanate group to the hydroxyl group in the urethanization reaction was 1.3.
Next, 7 parts of trimethylolpropane adduct of tolylene diisocyanate and 20 parts of ethyl acetate were added to obtain a polyisocyanate composition 1 having a solid content concentration of 80%.
The content of isocyanate groups in the polyisocyanate composition 1 was 4.20%, and the content of unreacted 4,4-diphenylmethane diisocyanate was 0.48%.

[Examples 2 to 5, Comparative Examples 1 to 3] Polyisocyanate compositions 2 to 8
The polyisocyanate group-containing polymer (A-2 to A-8) and the polyisocyanate composition containing the isocyanate group-containing polymer are the same as those of the polyisocyanate composition 1 except that the raw materials and the blending amounts shown in Table 1 are changed. Obtained 2-8.

The abbreviations in Table 1 are shown below.
PPG-2000: Polypropylene glycol with a number average molecular weight of about 2,000 PPG-400: Polypropylene glycol with a number average molecular weight of about 400 TMP: Trimethylol propane DPG: Dipropylene glycol TPG: Tripropylene glycol 4,4-MDI: 4,4 -Diphenylmethane diisocyanate TDI-TMP: Trimethylol propane adduct of toluene diisocyanate

<Manufacturing of polyol component>
(Polyester component (B-1))
In a reaction vessel equipped with a stirrer, a thermometer, a reflux cooling tube, a dropping tank and a nitrogen gas input tube, 8 parts of bifunctional polypropylene glycol having a number average molecular weight of 2,000 and 36 parts of bifunctional polypropylene glycol having a number average molecular weight of 400, Eight parts of trifunctional polypropylene glycol having a number average molecular weight of 400 was charged, and 17 parts of 4,4-diphenylmethane diisocyanate was charged into a reaction vessel while stirring while introducing nitrogen gas, and heated at 80 ° C. to 90 ° C. for 1 hour to urethane. A chemical reaction was carried out. Next, 0.05 part of phosphoric acid, 0.6 part of a silane coupling agent, and 30 parts of ethyl acetate were added to obtain a polyol component (B-1) which is a polyether urethane polyol.

(Polycarbonate component (B-2))
In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping tank and a nitrogen gas input tube, 6 parts of bifunctional polypropylene glycol having a number average molecular weight of 2,000 and 30 parts of bifunctional polypropylene glycol having a number average molecular weight of 400, 6 parts of trifunctional polypropylene glycol having a number average molecular weight of 400 were charged, and 10 parts of 4,4-diphenylmethane diisocyanate was charged into a reaction vessel while stirring while introducing nitrogen gas, and heated at 80 ° C. to 90 ° C. for 1 hour to urethane. A chemical reaction was carried out. Next, 0.05% phosphoric acid, 0.5% silane coupling agent, and 40 parts of ethyl acetate were added to obtain a polyol component (B-2) which is a polyether urethane polyol.

(Polycarbonate component (B-3))
120 parts of isophthalic acid, 300 parts of adipic acid, 60 parts of ethylene glycol, and 400 parts of neopentyl glycol were charged in a reaction vessel and heated to 250 ° C. to 260 ° C. while stirring under a nitrogen gas stream to carry out an esterification reaction. When the acid value becomes 10.0 mgKOH / g or less, the reaction temperature is set to 200 ° C., the inside of the reaction vessel is gradually depressurized, and the reaction is carried out at 1.3 kPa or less. The acid value is 0.4 mgKOH / g and the hydroxyl value is 50 mgKOH / g. , A polyol component (B-3) which is a polyester polyol having a secondary hydroxyl group at the terminal and having a number average molecular weight of about 2,200 was obtained.

<Manufacturing of adhesive composition>
[Example 6] (Preparation of adhesive composition 1)
100 parts of the polyisocyanate composition 1, 100 parts of the polyol component (B-1), 0.5 part of 3-glycidoxypropyltrimethoxysilane, 0.05 part of phosphoric acid, and 200 parts of ethyl acetate are mixed. Adhesive composition 1 was obtained.

[Examples 7 to 12, Comparative Examples 4 to 8] (Preparation of Adhesive Compositions 2 to 12)
The same actions as in the adhesive composition 1 were performed except that the materials and blending amounts shown in Table 2 were used, to obtain adhesive compositions 2 to 12.

<Evaluation of adhesive composition>
[Content of aromatic polyisocyanate (a1) in adhesive composition part]
Using the obtained adhesive composition, the content (% by mass) of the aromatic polyisocyanate (a1) in the adhesive composition was measured.

[Evaluation of initial cohesive force]
Using a simple test coater, a polyethylene terephthalate film (hereinafter referred to as PET) (trade name: E5102, thickness: 12 μm, manufactured by Toyobo Co., Ltd.) and a steel plate having a width of 25 mm were bonded together with an adhesive composition. The amount of the adhesive composition applied after drying was 22.5 g / m ² . Then, it was dried at 80 ° C. for 2 minutes in a heat circulation dryer.
For the obtained laminate, the adhesive strength between the PET and the steel plate was measured using an Instron type tensile tester according to the T type peeling test (JIS K 6854). The measurement was performed 5 times under the conditions of a test piece width of 25 mm and a tensile speed of 300 mm / min in an environment of 60 ° C., and the average value was calculated. The average value of the obtained adhesive strength was evaluated according to the following criteria.
S: Adhesive strength is 50N / 25mm or more (very good)
A: Adhesive strength is 40N / 25mm or more and less than 50N / 25mm (good)
B: Adhesive strength is 30N / 25mm or more and less than 40N / 25mm (usable)
C: Adhesive strength is 20N / 25mm or more and less than 30N / 25mm (cannot be used)
D: Adhesive strength is less than 10N / 25mm (defective)

[Slipperiness]
Biaxially stretched polypropylene film (trade name: P-2161, thickness: 20 μm, manufactured by Toyobo Co., Ltd.) using a solvent laminator (manufactured by Fuji Kikai Kogyo Co., Ltd .: FL-2) and a linear low density treated with surface corona discharge treatment. A density polyethylene film (hereinafter, LLDPE) (trade name: TUX-FCD, thickness: 50 μm, manufactured by Mitsui Chemicals Tohcello Co., Ltd.) was bonded with an adhesive composition. The amount of the adhesive applied after drying was 2.5 g / m ² . After bonding, they were trained at 40 ° C. for 3 days to obtain a laminated body having a composition of OPP / LLDPE.
Using a slip tester (manufactured by Yasuda Seiki Seisakusho Co., Ltd.), the coefficient of friction between the LLDPE surfaces was measured according to JIS K7152. Then, the sample was stored at 40 ° C. for 1 month, and then the coefficient of friction was measured again in the same manner as before storage. The measurement was performed 5 times, and the average value was calculated. The rate of change of the coefficient of friction before and after storage was calculated and evaluated according to the following criteria.
S: The rate of change of the coefficient of friction is less than 20% (very good)
A: The rate of change in the coefficient of friction is 20% or more and less than 40% (good).
B: The rate of change of the coefficient of friction is 40% or more and less than 60% (usable)
C: The rate of change of the coefficient of friction is 60% or more and less than 80% (cannot be used)
D: The rate of change of the coefficient of friction is 80% or more (defective)

[Preparation of laminated body]
Biaxially stretched polypropylene film (trade name: P-2161, thickness: 20 μm, manufactured by Toyobo Co., Ltd.) and aluminum-deposited non-stretched polypropylene film (hereinafter, VMCPP) using a solvent laminator (manufactured by Fuji Kikai Kogyo Co., Ltd .: FL-2). ) (Product name: Dialaster H27, Thickness: 12 μm, manufactured by Reiko Co., Ltd.) was bonded together with an adhesive composition. The amount of the adhesive applied after drying was 2.5 g / m ² . After bonding, they were trained at 40 ° C. for 3 days to obtain a laminated body having a composition of OPP / VMCPP.

[Laminate strength]
For the obtained laminate, the adhesive strength (N / 15 mm) between OPP and VMCPP was measured according to the T-type peeling test (JIS K 6854). The measurement was carried out in an environment of 20 ° C. using an Instron type tensile tester under the conditions of a test piece width of 15 mm and a tensile speed of 300 mm / min. The measurement was performed 5 times, and the average value was used for evaluation according to the following criteria.
S: Adhesive strength is 2N / 15mm or more (very good)
A: Adhesive strength is 1N / 15mm or more and less than 2N / 15mm (good)
B: Adhesive strength is 0.5N / 15m or more and less than 1N / 15mm (usable)
C: Adhesive strength is 0.1N / 15m or more and less than 0.5N / 15mm (cannot be used)
D: Adhesive strength is less than 0.1N / 15mm (defective)

[Evaluation of residual solvent]
A sample of 0.2 m ² was collected from the obtained laminate, shredded to a width of about 5 mm, and sealed in a 605 ml flask. After heating the flask at 80 ° C. for 30 minutes, 1 ml of the gas generated inside the flask was collected with a syringe, and the solvent concentration in the sample was measured using gas chromatography (manufactured by Shimadzu Corporation: GC-8A). The residual solvent amount (mg / m ² ) was calculated from the solvent concentration and evaluated according to the following criteria.
S: The amount of residual solvent is less than 2 mg / m ² (very good)
A: The amount of residual solvent is 2 mg / m ² or more and less than 5 mg / m ² (good).
B: The amount of residual solvent is 5 mg / m ² or more and less than 10 mg / m ² (usable)
C: The amount of residual solvent is 10 mg / m ² or more and less than 20 mg / m ² (cannot be used).
D: The amount of residual solvent is 20 mg / m ² or more (defective)

The abbreviations in Table 2 are shown below.
Silane coupling agent: 3-glycidoxypropyltrimethoxysilane MDI: diphenylmethane diisocyanate

From the results in Table 1, the polyisocyanate compositions of the present invention having a molar equivalent ratio during the urethane reaction in the range of 1.1 to 1.5 all have a diphenylmethane diisocyanate content of 1% by mass in the polyisocyanate composition. It showed a low value. On the other hand, the comparative example outside the above range greatly exceeded 1% by mass.

Further, from the results in Table 2, the adhesive composition using the polyisocyanate composition of the present invention not only has a small amount of diphenylmethane diisocyanate after blending the polyol component, but also has initial cohesive force, slipperiness, laminating strength, and residual solvent. Excellent results were also shown in the evaluation items of. In particular, Examples 6 to 9, 11 and 12 using the polyisocyanate composition reacted in the molar equivalent ratio range of 1.1 to 1.4 showed very excellent residual solvent and slipperiness. Further, Example 10 using the polyisocyanate composition reacted at a molar equivalent ratio of 1.5 showed very excellent initial cohesive force and laminating strength.
On the other hand, the adhesive compositions using the polyisocyanate compositions of the comparative examples all have a large amount of diphenylmethane diisocyanate, and the content in the adhesive composition exceeds 0.5% by mass, and further, the initial cohesive force and slippage. It was inferior in terms of properties and residual solvent.

Claims (7)

The molar equivalent ratio of the isocyanate group containing the aromatic polyisocyanate (a1) and the polyol containing the polyether polyol (a2) to the hydroxyl group in the polyol (number of moles of isocyanate group / hydroxyl group). A method for producing a polyisocyanate composition, which comprises reacting in a range where the number of moles) is 1.1 to 1.5. The method for producing a polyisocyanate composition according to claim 1, wherein the aromatic polyisocyanate (a1) is diphenylmethane diisocyanate or a derivative thereof. The method for producing a polyisocyanate composition according to claim 1 or 2, wherein the polyether polyol (a2) is polypropylene glycol. The method for producing a polyisocyanate composition according to claim 2 or 3, wherein the content of diphenylmethane diisocyanate or a derivative thereof in the polyisocyanate composition is 1% by mass or less. A method for producing an adhesive composition, which comprises a step of mixing the polyisocyanate composition produced by the method according to any one of claims 1 to 4 with the polyol component (B). The method for producing an adhesive composition according to claim 5, wherein the adhesive composition is a laminated adhesive for forming a packaging material. The adhesive composition produced by the method according to claim 5 or 6 is applied to a first sheet-like substrate to form an adhesive layer, and the second sheet-like substrate is laminated on the adhesive layer. A method for producing a laminated body, which comprises a step of curing the adhesive layer together.