JPS6146310B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method of laminating flexible substrates using organic solvent-free adhesives, and more particularly to a method for effectively laminating one flexible substrate to another flexible substrate. The present invention relates to a method which does not require long storage for the resulting laminate to develop the required bond strength. The field of the invention is that of flexible laminates, which are used in large numbers in a variety of applications. Laminates are useful in that they combine the advantageous features of two or more substrates in a single flexible material. For example, by laminating a polypropylene film and a K-cellophane (cellophane coated with vinylidene chloride) film together, the strength of the polypropylene film and the barrier properties of the K-cellophane film can be combined into a single flexible film. It can provide two properties: blocking and blocking properties. The present invention is an improved method for effectively laminating one flexible substrate to another flexible substrate, so that the resulting laminate quickly develops sufficient bonding strength and does not cause delamination. The present invention also relates to a method that does not require long-term storage so that sufficient bonding strength can be developed. Prior art lamination adhesives are generally organic solvent-containing materials. In view of the search for various ways to eliminate or reduce the use of organic solvents due to environmental, safety, and cost concerns, it would be desirable to provide a laminating adhesive that does not contain organic solvents. Although a number of organic solvent-free laminating adhesives are currently available, such as water-based and 100% solids systems, these adhesives have certain drawbacks. For example, water-based adhesives exhibit poor wetting properties when contacted with plastic films, tend to bead and do not flow uniformly over the substrate surface. Furthermore, sufficient energy is required to evaporate the water from the coated plastic film and metal foil. Additionally, water-based adhesives generally cannot provide sufficient bond strength and chemical and heat resistance required for plastic laminates. Regarding the 100% solids lamination adhesives currently used in the industry, one notable drawback is that the adhesives cannot be used at elevated temperatures to provide the fluidity necessary for coating onto substrates. It is something that must be done. However, the use of elevated temperatures requires precision weighing equipment to maintain appropriate temperature values so that the weight of the coating layer can be adjusted.
Furthermore, at elevated temperatures toxic fumes are sometimes generated which are hazardous to health and require special precautions. Finally, and perhaps most importantly, 100% solids adhesive systems cannot provide instant bond strength and rapid curing. As a result, special care must be taken to maintain accurate tension control when initially forming the laminate, otherwise one substrate may slide onto another. In the end, this gives a defective product. Without rapid curing, the laminate would need to be stored for an extended period of time before it is removed from the laminating machine so that sufficient bond strength can be developed. Therefore, an adhesive that does not contain organic solvents and has chemical resistance and heat resistance, and which can be obtained without the need for long-term storage of the laminate, can be applied to the laminate immediately after it comes out of the laminating machine. It would be desirable to provide a lamination method that utilizes adhesives that provide immediate bond strength. It is therefore an object of the present invention to provide a method for laminating one flexible substrate to another using an organic solvent-free adhesive. Another object of the invention is to bond one flexible substrate with an adhesive that provides instant bond strength so that the resulting laminate does not require long storage to develop the required bond strength. A method of laminating to another flexible substrate is provided. Yet another object of the present invention is to provide a method for laminating one flexible substrate to another using an adhesive with sufficient chemical and heat resistance. . These and other related objects of the present invention can be readily understood by reference to the following description. Generally, the present invention is a method of laminating one flexible substrate to another flexible substrate using an adhesive that does not contain an organic solvent, and the resulting laminate is suitable for industrial production of the laminate. In a method that has sufficient immediate bond strength and does not require long storage to develop bond strength, a reactant selected from the group consisting of polyether-based polyols and polyesters is reacted with a diisocyanate. A step (A) of coating the first base material with the initial polymer produced by the reaction, and supplying the base coated with the initial polymer to coat the uncoated second base material. (B) contact bonding; and (C) maintaining a supply of curing agent for the prepolymer in the contact zone between said first and second substrates; The curing agent is selected from the group consisting of primary amines, secondary amines, tertiary amines, and aqueous solutions of polyfunctional hydroxy-containing compounds and has the ability to combine with said initial polymer to form an adhesive. The present invention provides a method for laminating flexible substrates using an adhesive that does not contain an organic solvent. Alternatively, the method coats a first substrate with a prepolymer formed by reacting a diisocyanate with a reactant selected from the group consisting of polyether-based polyols and polyesters. (A), and adding a curing agent for the initial polymer selected from the group consisting of a primary amine, a secondary amine, a tertiary amine, and an aqueous solution of a polyfunctional hydroxy-containing compound to a second base material. step (B) of inducing the coated first and second substrates to contact and bond to each other, whereby the curing agent on the second substrate is Step (C) having the function of bonding with the initial polymer on the first substrate and thereby producing the adhesive;
It can consist of. According to the present invention, one flexible substrate can be laminated to another flexible substrate using an organic solvent-free adhesive to create a laminate with instant bond strength sufficient for industrial production of laminates. a step (A) of preparing a prepolymer by reacting a diisocyanate with a reactant selected from the group consisting of polyether-based polyols and polyesters; A curing agent for the prepolymer selected from the group consisting of amines, secondary amines, tertiary amines, and aqueous solutions of multifunctional hydroxy-containing compounds is mixed with said prepolymer to form said adhesive. step (B) of coating a first substrate with the adhesive, and applying the coated substrate to a second substrate, which may be uncoated or coated with the adhesive; There is also a method for laminating flexible substrates using an adhesive that does not contain an organic solvent, characterized in that it consists of a step (C) of contact bonding with a material to form a laminate of two substrates. provided. According to the present invention, there is provided a method for laminating one flexible substrate to another flexible substrate using an adhesive that does not contain an organic solvent, and the resulting laminate is manufactured by the industry of the laminate. In a process which has sufficient immediate bond strength for production and does not require long storage periods to develop bond strength, a reactant selected from the group consisting of polyether-based polyols and polyesters is used as a diisocyanate. a step (A) of coating the first base material with the initial polymer produced by reacting with a primary amine, a secondary amine, a tertiary amine and a polyfunctional hydroxy-containing compound; a step (B) of coating the first substrate coated with the initial polymer with a curing agent for the initial polymer selected from the group consisting of an aqueous solution and having an adhesive-forming action; The first substrate coated with an adhesive formed from a prepolymer and a curing agent for the prepolymer is induced to contact bond with a second substrate, thereby providing a laminate with immediate bond strength. There is also provided a method for laminating flexible substrates using an adhesive that does not contain organic solvents, characterized in that it consists of a step (C) of producing a body. The method of the present invention provides that (1) the resulting laminate exhibits immediate bond strength, i.e., a moderate bond strength sufficient to maintain the cohesion of the laminate is achieved within minutes;
(2) the bond strength increases rapidly to substantially its maximum strength within a few hours; and (3) the adhesive system has a sufficiently low viscosity that no heating is required during application and lamination; It overcomes the aforementioned drawbacks of the prior art in that it completely avoids the problems encountered with heating. The prepolymer used in the present invention is formed by reacting either (i) a polyether-based polyol or (ii) a polyester or a mixture thereof with a diisocyanate. Any diisocyanate having a free NCO group can be utilized. That is, an aliphatic or aromatic diisocyanate can be used to react with a polyether-based polyol or polyester to produce the prepolymer of the present invention. Examples of such diisocyanates include, but are not limited to: diphenylmethane diisocyanate, toluene 2,4-diisocyanate, toluene 2,6-diisocyanate, hexamethylene diisocyanate, p-phenylene diisocyanate, Nylene diisocyanate, m-phenylene diisocyanate, isophorone diisocyanate, trimethylhexamethylene diisocyanate, tetramethylene diisocyanate, 4,4'-methylene di-o-
Tolyl diisocyanate, naphthalene 1,5-diisocyanate and xylene diisocyanate. Mixtures of the aforementioned diisocyanates can be used, and even partially reacted reaction products of diisocyanates with polyhydroxy compounds such as dipropylene glycol or ethylene glycol. The polyether-based polyol of the present invention is a polyol in which oxyethylene, oxypropylene and oxybutylene bonds are present, and has the following formula: (wherein R is H or an alkyl group having 1 to 4 carbon atoms, and n is an integer from 4 to 200). Examples of compounds having oxyethylene, oxypropylene and oxybutylene bonds are polyoxyethylene glycol polyoxypropylene glycol, polyoxypropylene glycol butyl ether and mixed polyoxyethylene-polyoxypropylene glycol ether condensates (however, the average molecular weight is approximately 200 ~10.000). Any polyester or mixture thereof formed by reacting an aromatic or aliphatic dibasic acid with a polyhydroxy compound and having free hydroxyl groups is useful in the adhesive of the present invention. Polyesters formed by reacting adipic acid with diethylene glycol or polyesters formed by reacting isophthalic acid with 1,6-hexanediol can be used. Examples of commercially available polyesters include Rucoflex S-1021-
110" (this is the trade name for the ester of adipic acid and isofluic acid mixed with 1,4-butanediol), "Desmophen 1100"
There are polyesters such as "Desmccoll 12" and "Desmccoll 22". Polyesters having hydroxyl numbers of about 20 to about 150 are generally preferred. The prepolymer as described above is prepared by mixing either (i) a polyether-based polyol or (ii) a polyester or a mixture of (i) and (ii), as described above, with a diisocyanate, and then mixing this mixture with a diisocyanate. It is prepared by heating to a temperature in the range of 70-90 ° C for several hours. The end of the reaction can be confirmed by reaching a certain NCO content, as determined by periodic analysis during the reaction. It is understood that the prepolymer described above may be formed from components having various hydroxyl numbers and molecular weights, and certain mixtures of polyether-based polyols or polyesters and certain diisocyanates may be formed at the indicated temperature. It is understood that lower or higher temperatures may be required and that the time to complete the reaction will vary depending on the composition of the mixture. Furthermore, the proportions of the reactions used depend on the value of NCO content desired in the initial polymer and can be varied to suit the particular preselected properties desired in the final cured adhesive. Curing agents useful in reacting with and curing the prepolymer of the present invention to form adhesives with instant bond strength include amines such as primary amines, secondary amines, tertiary amines, and It is a polyfunctional hydroxy-containing compound with active hydrogen atoms. The amines mentioned above include substituted amines such as monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine and tris-[(β-hydroxyethoxy)-
ethyl]amine, diamine e.g. [N, N,
N',N'-tetrakis(2-hydroxypropyl)ethylenediamine] and polyethyleneimine, and polyethyleneimine has the structural formula (In the formula, R ₁ to _{R 4} are each selected from the group consisting of hydrogen and a lower alkyl group, and R ₅ is selected from the group consisting of hydrogen, a lower alkyl group, a hydroxy-substituted lower alkyl group, and a lower alkyl alkoxy group,
n is an integer). Said polyfunctional hydroxy-containing compounds include glycols, polyhydric alcohols such as glycerin, ether polyglycols, polyesters with free hydroxyl groups, epoxies, hydroxy acids and hydroxy-celluloses. The curing agent is provided as an aqueous solution at a convenient concentration to react with the free NCO groups of the prepolymer.
The amount of curing agent used is small compared to the amount of initial polymer and can vary depending on the desired properties of the adhesive. The hardeners described above are typically used in amounts up to 0.1 lb/ream. However, the amount of curing agent should not significantly exceed the stoichiometric amount required for the reaction. This is because the plasticizing effect of excess curing agent has a detrimental effect on the bond strength, and the bond strength is impaired in proportion to the excess amount. In one preferred embodiment of the invention, the prepolymer described above is reduced to a convenient coating weight, i.e. 3000
From about 0.5 to about 1.5 pounds per square foot series is coated onto a suitable substrate. The term "ream" as used herein refers to 3000 square feet of substrate. The prepolymer-coated substrate is fed to a conventional two-roller combination system consisting of a highly polished steel roller placed parallel to and spaced apart from the rubber roller. The spacing between said steel roller and rubber roller delimits a contact zone or nip into which an initial polymer coated substrate and a second uncoated substrate are provided; Make a contact bond. While feeding the prepolymer coated and uncoated substrates into the nip, the liquid hardener is in intimate and constant contact with each substrate. A small sphere is placed and maintained in the contact zone. The curing agent acts to instantaneously crosslink the initial polymer and impart the desired adhesive properties. As a result, when the two substrates exit the contact zone, they are immediately bonded and form a strongly bonded laminate within minutes, and the bond strength of the laminate reaches its maximum strength within a few hours. reach As noted above, the method of the present invention provides instant bond strength, and herein provides a bond strength of at least about 30 g within minutes as measured by the Amthor tensile tester described in Example 3 below. think it means. Achieving this instant bond strength means that the formed laminate can be rolled onto take-up rolls and transported without the need for long-term storage of the rolls to develop maximum bond strength. It is something that can be done. Laminates made in accordance with the present invention not only exhibit immediate bond strength, but in most cases exhibit maximum bond strength within only a few hours of lamination. The compound dibutyltin dilaurate is commonly used in the art as a curing catalyst to accelerate curing time and may be used in the present method. However, its use is not necessary to practice the invention.
This is because immediate and developed bond strength is achieved without the compound. In order to provide a thorough understanding of the present invention, the present invention is further illustrated by the following examples and comparative examples. Example 1 Preparation of initial polymer In a No. 3 flask equipped with a thermometer, a stirrer, and a reflux condenser, "Poly (Poly) G55-56" (this is
1500 g of a polyether-based polyol called polyoxypropylene-polyoxyethylene glycol condensate (trade name) having a hydroxyl number of 52.6 and an average molecular weight of 2000;
685.7 g of the reaction product of diphenylmethane diisocyanate and dipropylene glycol having an isocyanate equivalent weight of 152.1 (hereinafter referred to as "modified MDI") are charged. The mixture is heated to a temperature of 80-85°C for 4 hours under nitrogen atmosphere with constant stirring to complete the reaction. Completion of the reaction is indicated by reaching a certain NCO content. Each 3000 square feet of this initial polymer
“Mylar” up to 1.2 lb sheath weight
-92A” (trade name for a specific phthalate polyester film) onto a moving web. Lamination Method The Mylar (M) film coated with the prepolymer described above is fed into a conventional two roller bonding system.
The coupling system consists of a highly polished steel roller positioned parallel to and spaced apart from the rubber roller. The spacing between the steel roller and the rubber roller defines a contact zone or nip in which the prepolymer-coated mylar film and a second web of uncoated polyethylene (PE) film are disposed. supply and contact bond. While feeding the mylar and polyethylene webs into the nip, the liquid hardener consisting of a 10% aqueous solution of triethanolamine (TEA) is placed in intimate and constant contact with each web. of the microspheres are placed and maintained in the contact zone. When the mylar and polyethylene webs exit the nip, they are immediately bonded to form a tightly bonded laminate within minutes, and the bond strength of the laminate reaches its maximum strength within a few hours. . Comparative Example 1 As a control, the method of Example 1 is repeated except that no curing agent is used to form the Mylar and polyethylene laminate. Example 2 The method of Example 1 is repeated except that the curing agent is a 20% aqueous solution of TEA. Example 3 The method of Example 2 is repeated except that a web of K-cellophane (K-Cello) is used in place of the Mylar web. K-cello is cellophane coated on each side with polyvinylidene chloride. The bond strength of the adhesive used to form the laminates manufactured in Examples 1 to 3 and Comparative Example 1 was 1 to 2.
After hours, overnight, 2 days and after a storage period of 1 week, the measurements are made in a device called an Amthor tensile tester. The Asam-Tensile Tester is a device used in the packaging industry to measure bond strength. The device includes a pair of clamps or jaws, one of which is intended to grip the Mylar (or K-cello) portion of the laminate and the other intended to grip the PE portion of the laminate. Ru. A constant speed clamp separator driven by a motor is provided which separates and moves the clamps or jaws at a set speed. The motor is connected to a calibrated display that records the force, in grams, required to break the cohesion of a sample having a width of 2.54 cm. Table 1 shows the measurement results of lamination and bond strength of Examples 1 to 3 and Comparative Example 1. Atsumu - The force required to break the bond of the laminate when operating the tension tester at a speed of 25.4 cm (linear) per minute is 2.54 cm.
Record the number of grams per hit.

[Table] Approximately 100 to 350 g in approximately 1 hour when there is no film tearing (FT) or when the bonding strength of the adhesive is not greater than the adhesion of the polyvinylidene chloride coating layer to the cellophane substrate (KF). The bonding strength is considered to be appropriate and exhibits a bonding strength that is satisfactory for industrial use. If tearing of the film or separation of the coating layer occurs during the Assumu test described above, the bonding strength of the adhesive is clearly excellent. This is because the bonding force is greater than the strength of the film or the bonding force of the covering layer. That is, when the bonding of Examples 1, 2, and 3 is compared with the results of Comparative Example 1, the bonding strength of the cured adhesive of the present invention is superior after 1 to 2 hours after lamination and after overnight storage. However, when only the prepolymer without curing agent is used, it is clear that there is virtually no bonding. In Comparative Example 1, the bond strength shown after 2 days of storage was
It shows a value of 600g which rapidly decreases to 200g. The initially high bond strength of 600 is due to the curing of the initial polymer caused by atmospheric moisture. It should be noted that even without this moisture curing agent, it becomes more pronounced after one week of storage, achieving a bond strength of 500 g. However, since successful manufacturing capabilities require immediate bond strength, it is not practical commercially possible to wait a week to achieve a given bond strength. Example 4 The polyether-based polyol used is "Pluracol P2010" (which has a molecular weight of 57.1
The prepolymer is prepared by the method of Example 1, except that it is the trade name for polyoxypropylene glycol having a hydroxyl number of 200 and an average molecular weight of 200. This polyol is reacted with 812.8 g of modified MDI to form the prepolymer. This prepolymer is coated onto a moving web of K-Cellofilm to a coating weight of 1.2 pounds per ream. K-cellofilm coated with the above initial polymer using a 20% aqueous solution of TEA as a liquid curing agent.
The lamination method of Example 1 was followed except that the PE film was laminated. Example 5 The method of Example 4 was followed except that the prepolymer of Example 4 was coated onto a moving web of Mylar film to a coating weight of 0.84 pounds per ream and the same curing agent as in Example 4 was used. Mylar film coated with an initial polymer is laminated to PE film. Example 6 The method of Example 5 was followed except that the initial polymer was
Coated onto a moving web of Mylar film at a coating weight of 1.1 lbs per ream, 100% as hardener.
Mylar coated with a prepolymer is laminated to PE using TEA. The bond strength of the adhesives used to make the laminates of Examples 4-6 is measured as in Example 3. Table 2 shows the results of lamination and bond strength measurements of Examples 4 to 6.
Shown below.

TABLE The lack of bond strength of the laminate of Example 6 is due to the excessive amount of TEA. In excess,
TEA acts more as a plasticizer than as a hardener. The optimum amount of TEA curing agent is about half or less of the stoichiometric amount required. Comparative Example 2 A prepolymer is prepared according to the method of Example 1, except that the mixture of polyether-based polyols used in the reaction with modified MDI is as follows: 750 g of Pluracol P2010; Poly G55
-56 to produce a blended polyether-based polyol with an average hydroxyl number of 54.1. This mixture is then reacted with 723 g of modified MDI to form the prepolymer. This initial polymer is coated onto a transfer mylar web to a coating weight of 1.37 pounds per ream and laminated to polyethylene film using the lamination method of Example 1, but without the use of a curing agent. The formed laminate therefore serves as a control example. Example 7 The method of Comparative Example 2 is followed, except that in the lamination method a 15% aqueous solution of TEA is used as the liquid curing agent. Example 8 The method of Comparative Example 2 is followed, except that in the lamination method, a 5% aqueous solution of TEA is used as the liquid curing agent. Example 9 The method of Comparative Example 2 is followed, except that in the lamination process a 7.5% aqueous solution of TEA and an amine called by the trade name "Quadrol" (which is N,N,N',N'-tetrakis) are used as liquid hardeners. (2-hydroxypropyl)ethylenediamine) 7.5%
It uses a mixture of the same amount as an aqueous solution. Example 10 The method of Comparative Example 2 is followed, except that in the lamination method a 15% aqueous solution of triisopropanolamine (TIPA) is used as the liquid hardener. Example 11 The method of Comparative Example 2 is followed, except that in the lamination method a 15% aqueous solution of Quadrol is used as the liquid hardener. Example 12 The method of Comparative Example 2 is followed except that the coating weight of the initial polymer on the Mylar web is 1.34 lb/ream and the lamination process uses a 15% aqueous solution of diethanolamine (DEA) as the liquid hardener. . Example 13 The method of Comparative Example 2 is followed except that the coating weight of the initial polymer on the Mylar web is 0.77 lb/ream and the lamination process uses a 15% aqueous solution of diethanolamine (DEA) as the liquid hardener. . Example 14 The method of Example 9 is followed except that the coating weight of the prepolymer on the Mylar web is 0.77 lb/ream. Example 15 The method of Example 11 is followed except that the coating weight of the prepolymer on the Mylar web is 0.77 lb/ream. Some "tunnel scratches" were encountered in the laminates of Examples 7 to 12. "Tunnel flaw" describes a situation where one film does not laminate completely flat to another due to the films having different stretching properties. When this condition is encountered, it can be alleviated by adjusting the tension of the film during the lamination process. The bonding strength of the adhesive used to form the laminates manufactured in Comparative Example 2 and Examples 7 to 15 was measured in Example 3.
The results are shown in Table 3 below.

Table: Example 16 The method of Comparative Example 2 was followed, except that the coating weight of the initial polymer on the moving mylar web was 0.7 lb/ream, and in the lamination process, a 1% aqueous solution of polyethylene (PEI) was used as the liquid hardener. It is used. Example 17 The method of Example 16 is followed except that the liquid hardener is
It is a 2.5% aqueous solution of PEI. The bond strengths of the adhesives used to form the laminates made in Examples 16 and 17 were measured as in Example 3 and are shown in Table 4 below.

EXAMPLE 18 A prepolymer is prepared according to the method of Example 1, except that polyester is used instead of the polyether-based polyol. Said polyester is a polyester designated by the trade name "Rucoflex S-1011", which is a saturated aliphatic linear hydroxyl terminated polyester having a hydroxyl number of 38.3. 500 g of Lucoflex S-1011 is reacted with 311.2 g of modified MDI as in Example 1 to form a prepolymer. 1.7 pounds of this initial polymer
A coating weight of 50% is applied onto a moving web of Mylar and laminated onto a polyethylene film using the lamination method of Example 1, except that a 15% aqueous solution of Quadrol is used as the liquid hardener. The adhesive strength of the formed laminate was tested as in Example 3 with the following results. Bond Strength After 1-5 hours After 1 day After 1 week 250 500z (FT) 600FH Example 19 An initial polymer was prepared by the method of Comparative Example 2 and transferred onto a Mylar web to a coating weight of 0.9 lb/ream. coated and then laminated to a polyethylene film by the method of Example 1.
In the lamination method, a 15% aqueous solution of glycerin is used as a liquid curing agent. The bond strength at various time intervals was measured as in Example 3 and is shown in Table 4, 2.

[Table] The laminate of Example 19 was aged for one week at ambient temperature,
Then, it is formed into a pouch. The sachet is filled with a mixture of equal parts vegetable oil, vinegar and ketchup and then boiled for 1 hour, after which the bond strength is measured again. The bond strength was found to be 460, demonstrating the strength, heat resistance, and chemical resistance of the laminate of the present invention. Example 20 The method of Example 19 is followed except that a 5% aqueous solution of tartaric acid is used as the curing agent. Example 21 Hydroxyethylcellulose 2 as a curing agent
The method of Example 19 is followed except that a % aqueous solution is used. The bond strengths of the laminates formed in Examples 20 and 21 were measured as in Example 3 and are shown in Table 5.

[Table] Xyethyl Cellulose Example 22 A laminating adhesive is prepared from components A and B in the following manner. Ingredients A: 712g of Pullulacol P2010 into Pullulacol P
-410 (same as P2010 except the molecular weight is 400)
to form a mixture having a hydroxyl number of 100. Add 45g of TEA to this with constant stirring. Ingredient B 110g of dipropylene glycol for 4 hours 80~
React with 1981.5 g of modified MDI at a temperature of 85°C.
Components A and B are combined in the ratio of 315 g A to 234 g B and thoroughly mixed to form the adhesive product. Lamination Method Mylar film is laminated to polyethylene film by coating the above adhesive product onto the film to a coating weight of 0.54 lb/ream. The adhesive-coated Mylar film and polyethylene film described above are individually fed into the nip of a conventional two-roller bonding system as described in Example 1, where they are contact bonded to form a Mylar (M)-polyethylene (PE) film. Form a laminate. Example 23 The method of Example 22 is followed except that the nylon 77 film is laminated to the polyethylene film. Example 24 The method of Example 22 is followed except that the aluminum foil is laminated to the polyethylene film. Example 25 The method of Example 22 is followed except that the K-cellofilm is laminated to the polypropylene (PP) film. Example 26 The method of Example 22 is followed except that K-cellofilm is laminated to K-cellofilm. The bond strengths of the laminates formed in Examples 22 to 26 were measured by the method described in Example 3, and the results shown in Table 6 below were obtained.

[Table] B Example 27 Example 22 except that 27 g of glycerin and 0.09 g of dibutyltin dilaurate (DBTDL) were used instead of 45 g of TEA in component A, and 309 g of component A was mixed with 234 g of component B. A lamination adhesive is manufactured using the composition described in . Lamination method: 0.46 lb/kg on one side of two sheets of K-cellofilm
K by coating the adhesive up to the coating weight of the reams.
- Laminated to cellophyl film. The adhesive coated K-cellofilm is laminated to the K-cellofilm by the method described in Example 22. Example 28 The method of Example 27 is followed except that the K-cellofilm is laminated to the polypropylene film. Example 29 The method of Example 27 is followed except that the aluminum foil is laminated to the polyethylene film. Example 30 The method of Example 27 is followed except that the nylon 77 film is laminated to the polyethylene film. Example 31 The method of Example 27 is followed except that the Mylar film is laminated to the polyethylene film. Example 32 Example except the coating weight is 0.69 lb/ream
Follow 31 methods. The bond strength of the laminates of Examples 27-32 is measured by the method described in Example 3. The results obtained are summarized in Table 7 below.

Table Example 33 A laminating adhesive is prepared from components A and B as follows: Component A 754 g of Pluracol P2010 are mixed with 146 g of Pluracol P410 until homogeneous to form a mixture having a hydroxyl number of 90. Form. Add 30 g of TEA to this mixture with constant stirring. Component B A reaction product of diphenylmethane diisocyanate and dipropylene glycol with a dipropylene glycol content of approximately 10% by weight. Components A and B are combined in a ratio of 350 g A to 250 g B, or 7 parts A to 5 parts B, and mixed thoroughly to form the adhesive product. Lamination Method Mylar film is laminated to polyethylene film by coating the above adhesive onto the Mylar film to a coating weight of 0.53 lb/ream. The adhesive coated Mylar film is laminated to the polyethylene film by the method described in Example 22. Example 34 Nylon 77 film is bonded to polyethylene film using the adhesive of Example 33 and the lamination process described therein. Example 35 The method of Example 33 is followed except that 300 g of component A is combined with 300 g of component B (ratio of A and B is 1:1) to form an adhesive product. Example except coating weight is 0.50 lb/ream
Mylar film is laminated to polyethylene film by the method described in 33. Example 36 The method of Example 35 is followed except that the nylon 77 film is bonded to the polyethylene film. Example 37 Example 33 except that 400 g of component A is combined with 200 g of component B (ratio of A and B is 2:1).
Follow the method. Adhesive coverage weight is 0.52 lb/
The mylar film is bonded to the polyethylene film by the lamination method described in Example 33, except that the film is continuous. Example 38 The method of Example 37 is followed except that the nylon 77 film is bonded to the polyethylene. Example 39 A mixture of 15g TEA and 9g glycerin
The method of Example 33 is followed to form the adhesive, except that 30 g of TEA alone is used in component A. Example except coating weight is 0.69 lb/ream
The mylar film is bonded to the polyethylene film by the lamination method of 33. Example 40 The method of Example 39 is followed except that the aluminum foil (F) is bonded to the polyethylene film. Example 41 The method of Example 39 is followed except that the aluminum foil is bonded to the Mylar film. The bond strength of the laminates of Examples 33 to 41 is measured by the method of Example 3. The results are summarized in Table 8.

[Table] Example 42 The prepolymer was prepared by the method of Example 1 except that a polyether-based polyol-based polyol mixture was used in the reaction with diphenylmethane diisocyanate (DMI) as follows. Manufacture: 700g of Pluracol P2010 to 700g of Poly G55
-56 to produce a blended polyether-based polyol with an average hydroxyl number of 57.2. This mixture is reacted with 537.0 g of MDI to form the prepolymer. This prepolymer was coated onto a moving web of K-Cellofilm to a coating weight of 0.5 lb/ream;
The coated film is laminated to a polyethylene film by the method of Example 1, except that the curing agent is a 15% aqueous solution of Quadol. Example 43 The method of Example 42 is followed except that the curing agent is a 15% aqueous solution of triethanolamine. Example 44 The method of Example 43 is followed except that the prepolymer is coated onto a moving web of Mylar film and then laminated to polyethylene film. The bond strengths of the adhesive binders used to form the laminates of Examples 42-44 were measured as in Example 3 and are shown in Table 9.

[Table] Example 45 A prepolymer is prepared by the method of Example 1, except that 261.9 g of industrial grade polymer containing 1500 g of Pluracol P2010 (hydroxyl number 56.3) and 8% of toluene 2,4-diisocyanate is prepared. toluene diisocyanate to form an initial polymer. This prepolymer was coated onto a moving web of K-Cellofilm to a coating weight of 0.5 lb/ream;
The coated film is laminated to a polyethylene film by the method of Example 1, except that the curing agent is a 15% aqueous solution of Quadrol. Example 46 The method of Example 45 is followed except that the prepolymer described above is coated onto a moving web of Mylar film and then laminated to polyethylene film. Example 47 The method of Example 46 is followed except that the curing agent is a 15% aqueous solution of triethanolamine instead of Quadrol. Example 48 The procedure of Example 47 is followed except that the prepolymer described above is coated onto a transfer layer of K-cellofilm and then laminated to a polyethylene film. The bond strengths of the adhesives used to form the laminates of Examples 45-48 were measured as in Example 3 and are shown in Table 10.

EXAMPLE 49 The prepolymer of Comparative Example 2 is coated onto a moving web of Mylar film to a coating weight of 0.5 lb/ream. The coated Mylar film is laminated to a polyethylene film by the lamination method of Example 1, except that the curing agent used is a 15% aqueous solution of Quadrol. Example 50 The method of Example 49 is repeated except that the prepolymer is coated onto a moving web of nylon 77 film, which is then laminated to polyethylene film. The immediate (i.e., after 5 minutes) bond strength of the adhesives used to form the laminates of Examples 49 and 50 was determined in Example 1.
The results were measured as shown in Table 11 below.

[Table] The immediate bond strength, i.e. a bond strength of about 30 g within a few minutes, is quite sufficient to enable the resulting laminate to be fed onto a winding roll for transport or subsequent storage; is quite sufficient in view of the fact that the value increases rapidly to excellent values within about 15 minutes to 1 hour.

Claims (1)

[Claims] 1. Lamination of one flexible substrate to another using an organic solvent-free adhesive to provide instant bond strength sufficient for industrial production of laminates. In a method for producing a laminate having a polyester base, an initial polymer produced by reacting a diisocyanate with a reactant selected from the group consisting of a polyether-based polyol and a polyester is placed on a first substrate. coating step (A), and supplying the substrate coated with the initial polymer to coat the uncoated second substrate.
and step C of maintaining a supply of curing agent for the initial polymer in the contact zone between said first and second substrates,
Said curing agent is selected from the group consisting of primary amines, secondary amines, tertiary amines, and aqueous solutions of multifunctional hydroxy-containing compounds and combines with said prepolymer to form an adhesive. 1. A method for laminating flexible substrates using an adhesive that does not contain an organic solvent, characterized in that the adhesive has the following properties: 2 said prepolymer is produced from the reaction between a diisocyanate and a polyether-based polyol, said diisocyanate being the reaction product of diphenylmethane diisocyanate and dipropylene glycol; A method according to claim 1, wherein the polyol based on polyoxypropylene-polyoxyethylene condensate. 3. The method according to claim 1, wherein the curing agent is an aqueous solution of triethanolamine. 4. The method according to claim 1, wherein the curing agent is an aqueous solution of diethanolamine. 5. The method according to claim 1, wherein the curing agent is an aqueous solution of triisopropanolamine. 6 The curing agent is N, N, N', N'-tetrakis (2
2. The method according to claim 1, which is an aqueous solution of ethylene diamine (hydroxypropyl). 7. The method according to claim 1, wherein the curing agent is an aqueous solution of polyethyleneimine. 8. The method according to claim 1, wherein the curing agent is an aqueous solution of glycerin. 9. The method of claim 1, wherein the curing agent is an aqueous solution of tartaric acid. 10. The method according to claim 1, wherein the curing agent is an aqueous solution of hydroxyethyl cellulose. 11. Claims in which the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of triethanolamine. The method described in paragraph 1. 12. Claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of diethanolamine. Method described. 13 The diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of triisopropanolamine. The method described in Section 1. 14. Claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of polyethyleneimine. The method described in section. 15 The diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is N,N,N',N'-tetrakis ( 2-Hydroxypropyl) ethylenediamine in an aqueous solution. 16. Claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of glycerin. Method described. 17. Claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of tartaric acid. Method described. 18 Claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of hydroxyethyl cellulose. The method described in section. 19. The method of claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of triethanolamine. 20. The method of claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of diethanolamine. 21. The method of claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of triisopropanolamine. 22. The method of claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of polyethyleneimine. 23. Claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is polyester, and the curing agent is an aqueous solution of N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine. The method described in section. 24. The method of claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of glycerin. 25. The method of claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of tartaric acid. 26. The method of claim 1, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of hydroxyethyl cellulose. 27. The method according to claim 1, wherein the diisocyanate is toluene diisocyanate, the polyether-based polyol is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of triethanolamine. Method. 28. The method according to claim 1, wherein the diisocyanate is toluene diisocyanate, the polyether-based polyol is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of diphenolamine. Method. 29. The method according to claim 1, wherein the diisocyanate is toluene diisocyanate, the polyether-based polyol is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of triisopropanolamine. Method. 30. The method of claim 1, wherein the diisocyanate is toluene diisocyanate, the polyether-based polyol is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of polyethyleneimine. . 31 The diisocyanate is toluene diisocyanate, the polyether-based polyol is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is N, N, N',
The method according to claim 1, which is an aqueous solution of N'-tetrakis(2-hydroxypropyl)ethylenediamine. 32. The method of claim 1, wherein the diisocyanate is toluene diisocyanate, the polyether-based polyol is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of glycerin. 33. The method of claim 1, wherein the diisocyanate is toluene diisocyanate, the polyether-based polyol is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of tartaric acid. 34. The method of claim 1, wherein the diisocyanate is toluene diisocyanate, the polyether-based polyol is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of hydroxyethyl cellulose. . 35 Laminating one flexible substrate to another using an organic solvent-free adhesive to produce a laminate with sufficient immediate bond strength for industrial production of laminates In the method, an initial polymer formed by reacting a diisocyanate with a reactant selected from the group consisting of polyether-based polyols and polyesters is first
A step (A) of coating the base material with a primary amine,
(B) coating the second substrate with a curing agent for the prepolymer selected from the group consisting of secondary amines, tertiary amines, and aqueous solutions of polyfunctional hydroxy-containing compounds; The coated first and second substrates are induced to contact bond with each other such that the curing agent on said second substrate is bonded to the initial polymer on said first substrate. a process which has the function of combining with and thereby producing said adhesive.
(C) A method for laminating flexible substrates using an adhesive that does not contain an organic solvent. 36. The method of claim 35, wherein the curing agent is an aqueous solution of triethanolamine. 37. The method of claim 35, wherein the curing agent is an aqueous solution of diethanolamine. 38. The method of claim 35, wherein the curing agent is an aqueous solution of triisopropanolamine. 39. The method of claim 35, wherein the curing agent is an aqueous solution of N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine. 40. The method of claim 35, wherein the curing agent is an aqueous solution of polyethyleneimine. 41. The method of claim 35, wherein the curing agent is an aqueous solution of glycerin. 42. The method of claim 35, wherein the curing agent is an aqueous solution of tartaric acid. 43. The method according to claim 35, wherein the curing agent is an aqueous solution of hydroxyethyl cellulose. 44 The diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of triethanolamine. The method according to item 35. 45. Claim 35, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of diethanolamine. Method described. 46 The diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of triisopropanolamine. The method according to item 35. 47 The diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is N,N,N',N'-tetrakis ( 36. The method according to claim 35, which is an aqueous solution of 2-hydroxypropyl)ethylenediamine. 48 Claim 35, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of polyethyleneimide. The method described in section. 49. Claim 35, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of glycerin. Method described. 50 The diisocyanate is diphenylmethane diisocyanate, and the polyether-based polyol reactant is polyoxypropylene-
36. The method of claim 35, wherein the polyoxyethylene condensate is a polyoxyethylene condensate and the curing agent is an aqueous solution of tartaric acid. 51. Claim 35, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of hydroxyethyl cellulose. The method described in section. 52 Laminating one flexible substrate to another using an organic solvent-free adhesive to produce a laminate with sufficient immediate bond strength for industrial production of laminates in a method, preparing a prepolymer by reacting a diisocyanate with a reactant selected from the group consisting of polyether-based polyols and polyesters;
(A) and a curing agent for the prepolymer selected from the group consisting of a primary amine, a secondary amine, a tertiary amine, and an aqueous solution of a polyfunctional hydroxy-containing compound, mixed with said prepolymer. step (B) of coating the adhesive on a first substrate and contact bonding the coated substrate with a second substrate to form the two substrates; A method for laminating flexible substrates using an adhesive that does not contain an organic solvent, the method comprising the step of (C) producing a laminate. 53 The diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of triethanolamine. The method according to item 52. 54. Claim 52, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of diethanolamine. Method described. 55 Claim No. 5, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of triisopropanolamine. The method according to item 52. 56 The diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is N,N,N',N'-tetrakis ( 53. The method of claim 52, wherein the aqueous solution is 2-hydroxypropyl)ethylenediamine. 57. Claim 52, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of polyethyleneimine. The method described in section. 58. Claim 52, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of glycerin. Method described. 59 Claim 52, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of hydroxyethylcellulose. The method described in section. 60 A method of laminating one flexible substrate to another flexible substrate using an adhesive that does not contain an organic solvent, and the resulting laminate is sufficient for industrial production of the laminate. Reacting a diisocyanate with a reactant selected from the group consisting of polyether-based polyols and polyesters in a process that has immediate bond strength and does not require long storage periods to develop bond strength. Step (A) of coating the first base material with the initial polymer produced by
and a curing agent for the prepolymer selected from the group consisting of primary amines, secondary amines, tertiary amines, and aqueous solutions of polyfunctional hydroxy-containing compounds and having adhesive-forming properties. Step (B) of coating the first substrate coated with the initial polymer of
and directing said first substrate coated with an adhesive formed from said prepolymer and a curing agent for said prepolymer to contact bond with a second substrate, thereby immediately bonding. Process of producing a laminate with strength (C)
A method for laminating flexible substrates using an adhesive that does not contain an organic solvent, characterized in that the method comprises: 61 Said prepolymer is produced from the reaction between a diisocyanate and a polyether-based polyol, said diisocyanate being the reaction product of diphenylmethane diisocyanate and dipropylene glycol, said polyether 61. The method of claim 60, wherein the polyol based on polyoxypropylene-polyoxyethylene condensate. 62. The method of claim 60, wherein the curing agent is an aqueous solution of triethanolamine. 63. The method of claim 60, wherein the curing agent is an aqueous solution of diethanolamine. 64. The method according to claim 60, wherein the curing agent is an aqueous solution of triisopropanolamine. 65. The method of claim 60, wherein the curing agent is an aqueous solution of N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine. 66. The method of claim 60, wherein the curing agent is an aqueous solution of polyethyleneimine. 67. The method of claim 60, wherein the curing agent is an aqueous solution of glycerin. 68. The method of claim 60, wherein the curing agent is an aqueous solution of tartaric acid. 69. The method of claim 60, wherein the curing agent is an aqueous solution of hydroxyethyl cellulose. 70 The diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of triethanolamine. The method according to item 60. 71 Claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of diethanolamine. Method described. 72 The diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of triisopropanolamine. The method according to item 60. 73. Claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of polyethyleneimine. The method described in section. 74 The diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is N,N,N',N'-tetrakis ( 61. The method of claim 60, wherein the aqueous solution is 2-hydroxypropyl)ethylenediamine. 75 Claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of glycerin. Method described. 76 Claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of tartaric acid. Method described. 77 Claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the polyether-based polyol reactant is a polyoxypropylene-polyoxyethylene condensate, and the curing agent is an aqueous solution of hydroxyethyl cellulose. The method described in section. 78. The method of claim 60, wherein the diisocyanate is diphenylmemon diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of triethanolamine. 79. The method of claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of diethanolamine. 80. The method of claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of triisopropanolamine. 81. The method of claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of polyethyleneimine. 82 Claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine. The method described in section. 83. The method of claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of glycerin. 84. The method of claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of tartaric acid. 85. The method of claim 60, wherein the diisocyanate is diphenylmethane diisocyanate, the reactant is a polyester, and the curing agent is an aqueous solution of hydroxyethyl cellulose.