JP5544724B2 - Aqueous polyurethane resin composition and molded film using the same - Google Patents

Description

  The present invention relates to an aqueous polyurethane resin composition and a film molding such as a glove produced using the same.

  From the viewpoints of flammability, work environment, and ease of handling, replacement of water-based polyurethane resins has been advanced with applications in which solvent-based polyurethane has been conventionally used, such as paints, adhesives, and film molded bodies.

  Among these, examples of applications that require a film thickness include film molded bodies such as thick paints, waterproof materials, and gloves (for example, Patent Document 1). Usually, in such applications, a production method in which an aqueous polyurethane resin having a high resin solid content concentration is used and dried at a high temperature after application or immersion is advantageous from the viewpoint of shortening the drying time.

  However, for example, when trying to obtain an appropriate film thickness (100 to 300 μm) as a glove, the film surface swells (peeling from the base material) or bubbles are caused by the influence of water that evaporates during drying, or the film surface becomes rough. There were problems and it was difficult to obtain a homogeneous product. In addition, in order to ensure the film thickness, there has been a problem that the production cost increases when a plurality of times of application and immersion are performed.

JP-A-2005-306893

  The present invention has been made in view of the above problems, and an object of the present invention is to use an aqueous polyurethane resin composition capable of obtaining a homogeneous film molded body free from blisters and bubbles even when molded at a high temperature, and the same. A molded film produced by the method is provided.

  As a result of intensive studies to solve the above problems, the present inventors have used a composition containing a specific aqueous polyurethane resin and a nonionic surfactant, so that even when dried at a high temperature. Thus, it has become possible to produce a homogeneous film molding, and has found a new fact that the obtained film has mechanical properties that can be used for, for example, gloves, and has completed the present invention. That is, the present invention is an aqueous polyurethane resin composition containing an aqueous polyurethane resin produced from a polyisocyanate and a polyhydroxy compound and a nonionic surfactant, and having a resin solid content concentration of 50% by weight or more, An aqueous polyurethane resin composition in which the aqueous polyurethane resin satisfies specific conditions, and a film molded product produced using the same.

  Hereinafter, the present invention will be described in detail.

  The aqueous polyurethane resin composition of the present invention comprises an aqueous polyurethane resin produced from a polyisocyanate and a polyhydroxy compound and a nonionic surfactant, and has a resin solid content concentration of 50% by weight or more. The aqueous polyurethane resin is an aqueous polyurethane resin composition that satisfies the following conditions.

(A) 50% by weight or more of the polyisocyanate is diphenylmethane diisocyanate (A) The hydrophilic group contained in the aqueous polyurethane resin is 0.03 to 0.30 mmol with respect to 1 g of resin solid content. The product contains an aqueous polyurethane resin produced from a polyisocyanate and a polyhydroxy compound and a nonionic surfactant.

  The aqueous polyurethane resin is obtained by reacting at least a polyisocyanate and a polyhydroxy compound to obtain a prepolymer, and then extending the chain before, during or after emulsification.

  The polyisocyanate used for producing the aqueous polyurethane resin needs to be 50% by weight or more of diphenylmethane diisocyanate. When diphenylmethane diisocyanate is less than 50% by weight, the physical properties of the film are lowered. The amount is preferably 60 to 95% by weight in order to prevent the generation of aggregates and to prevent deterioration of physical properties and appearance when a film is formed.

  The aqueous polyurethane resin contains a hydrophilic group. Here, the hydrophilic group is an anionic group such as a carboxylic acid group or a sulfonic acid group, and an anionic group obtained by neutralizing these with a basic compound such as sodium hydroxide or tertiary amine.

  The amount of the hydrophilic group contained in the aqueous polyurethane resin is required to be 0.03 to 0.30 mmol, preferably 0.05 to 0.15 mmol, with respect to 1 g of the resin solid content. When the hydrophilic group is less than 0.03 mmol, the dispersion stability of the aqueous polyurethane resin is insufficient and phase separation tends to proceed. On the other hand, if it exceeds 0.30 mmol, the average particle size becomes too small, the viscosity increases, it becomes difficult to sufficiently increase the resin solid content concentration, and the water resistance of the dried coating film may be further lowered. .

  Examples of the nonionic surfactant contained in the aqueous polyurethane resin composition of the present invention include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene octyl phenyl ether, and polyoxyethylene nonyl phenyl ether. Polyoxyethylene alkyl phenyl ether, ethylene oxide adduct of acetylenic diol, polyoxyethylene derivative, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, fatty acid monoglyceride, polyethylene glycol fatty acid ester, polyoxyethylene alkyl such as polyoxyethylene laurylamine An amine etc. are mentioned.

  The content of the nonionic surfactant varies depending on the type of the surfactant and the hydrophobicity of the polymer, but is preferably 0.1 to 5% by weight, more preferably in the aqueous polyurethane resin composition of the present invention. 0.2 to 3% by weight. Moreover, as preferable HLB of a nonionic active agent, it is 12-20, More preferably, it is 14-17.

  The aqueous polyurethane resin composition of the present invention needs to have a resin solid content concentration of 50% by weight or more, preferably 55 to 80% by weight, more preferably 60 to 75%, from the viewpoint of shortening drying time and suppressing swelling. % By weight. When the resin solid content concentration is less than 50% by weight, a long drying time is required, and swelling is likely to occur due to evaporation of moisture, resulting in poor film appearance. Here, the resin solid content concentration is obtained by measuring the non-volatile content by volatilizing water or a solvent, obtained as a ratio to the original weight, and according to the test method of the synthetic resin emulsion defined in JIS K 6828-1. It can be measured.

  The average particle size of the aqueous polyurethane resin composition of the present invention is not particularly limited, but it is 0 in order to increase the resin solid content concentration to ensure an appropriate viscosity and to maintain the stability of the aqueous polyurethane resin composition. 0.05 to 5.0 μm is preferable, more preferably 0.1 to 3.0 μm, and still more preferably 0.2 to 1.5 μm.

  Examples of the method for producing the aqueous polyurethane resin composition of the present invention include: (a) Prepolymer obtained by reacting a polyisocyanate, a polyhydroxy compound and a polyhydroxy compound having a hydrophilic group with a nonionic surfactant. After emulsification, the chain is extended. (B) A prepolymer obtained by reacting a polyisocyanate and a polyhydroxy compound is chain-extended with a polyamine compound having a hydrophilic group, and then in the presence of a nonionic surfactant. Emulsification and the like.

  Among the polyisocyanates used in the present invention, examples of diphenylmethane diisocyanate include 2,4′-diphenylmethane diisocyanate, 4,4′-diphenylmethane diisocyanate, crude MDI, a mixture thereof, and the like.

  Examples of polyisocyanates other than diphenylmethane diisocyanate include aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates, and araliphatic polyisocyanates. Examples of the aliphatic polyisocyanate include 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, Examples of alicyclic polyisocyanates include 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanatomethyl) cyclohexane, 3-isocyanatomethyl-3, and the like. 3,5-trimethylcyclohexane (isophorone diisocyanate), bis- (4-isocyanatocyclohexyl) methane (hydrogenated MDI), norbornane diisocyanate and the like, and as aromatic polyisocyanate, For example, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 3,3′-dimethyl-4,4′-diisocyanatobiphenyl, 3,3′-dimethyl-4 , 4'-diisocyanatodiphenylmethane, 1,5-naphthylene diisocyanate and the like, and examples of the araliphatic polyisocyanate include 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, α, α , Α ′, α′-tetramethylxylylene diisocyanate and the like. Mixtures of these can also be used.

  The polyisocyanate used in the present invention needs to be 50% by weight or more of diphenylmethane diisocyanate. When diphenylmethane diisocyanate is less than 50% by weight, the physical properties of the film are lowered. The amount is preferably 60 to 95% by weight in order to prevent the generation of aggregates and to prevent deterioration of physical properties and appearance when a film is formed.

  The polyhydroxy compound used in the present invention is a compound containing two or more hydroxyl groups having reactivity with isocyanate groups.

  Examples of the polymer polyhydroxy compound having a molecular weight of 400 or more include polyester polyol (a), polyether polyol (b), and a mixture of two or more thereof.

  Examples of the polyester polyol (a) include condensed polyester polyol (a1), polycarbonate polyol (a2), polylactone polyol (a3) and the like.

  Examples of the condensed polyester polyol (a1) include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1 , 6-hexanediol, neopentyl glycol, butyl ethyl propane diol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol and other diols and succinic acid, adipic acid, azelaic acid, sebacine Acid, dodecanedicarboxylic acid, maleic anhydride, fumaric acid, 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, naphthalene Examples include reactants with dicarboxylic acids such as rubonic acid, such as polyethylene adipate diol, polybutylene adipate diol, polyhexamethylene adipate diol, polyneopentylene adipate diol, polyethylene propylene adipate diol, polyethylene butylene adipate diol. Examples thereof include adipate condensation polyester diols such as polybutylene hexamethylene adipate diol and poly (polytetramethylene ether) adipate diol, and azelate condensation polyester diols such as polyethylene azelate diol and polybutylene azelate diol.

  Examples of the polycarbonate polyol (a2) include a reaction product of a dialkyl carbonate as typified by the above diols and dimethyl carbonate, and specific examples thereof include polytetramethylene carbonate diol, poly 3-methylpentamethylene. Examples thereof include carbonate diol and polyhexamethylene carbonate diol.

  Examples of the polylactone polyol (a3) include ε-caprolactone, γ-butyrolactone, γ-valerolactone, and a ring-opening polymer of a mixture of two or more thereof. Specific examples include polycaprolactone diol and the like. It can be illustrated.

  Examples of the polyether polyol (b) include ethylene glycol, propylene glycol, 1,3-butylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, neopentyl glycol, catechol, hydroquinone, and bisphenol A. 1 type or 2 types of monomers such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, tetrahydrofuran, cyclohexylene, etc., with one or more compounds having at least two active hydrogen atoms as initiators A reaction product obtained by addition polymerization of the above can be mentioned. In the case of a reaction product obtained by addition polymerization of two or more monomers, block addition, random addition, or a mixed system of both may be used. Specific examples include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol and the like.

  Among these polymer polyhydroxy compounds, polypropylene glycol and polytetramethylene ether glycol are preferable, and polytetramethylene ether glycol is more preferable from the viewpoint of water resistance of the molded film. In the case of a mixture of two or more, it is preferable that 30% by weight or more of the polyhydroxy compound is polytetramethylene ether glycol.

  The hydroxyl value of the polymer polyhydroxy compound is preferably 10 to 300 mgKOH / g, more preferably 20 to 250 mgKOH / g. The hydroxyl value is determined by the method specified in JIS-K0070, that is, the sample solution prepared by adding acetic anhydride and pyridine to the sample to dissolve, allowing to cool, and adding water and toluene after neutralization is neutralized with a KOH ethanol solution. It can be measured by titration. The hydroxyl value is represented by the number of mg of potassium hydroxide required to neutralize acetic acid consumed to acetylate the hydroxyl group contained in a 1 g sample.

  Examples of the low molecular weight polyhydroxy compound having a molecular weight of less than 400 include ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentanediol. 1,6-hexanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, tripropylene glycol and other aliphatic diols, glycerin, trimethylolpropane, pentaerythritol and other polyfunctional aliphatic polyols, 1,4-cyclohexane Diols, 1,4-cyclohexanedimethanol, alicyclic diols such as hydrogenated bisphenol A, aromatic diols such as bisphenol A, hydroquinone, bishydroxyethoxybenzene, and alkylene oxide adducts thereof Polyol, and the like.

  Examples of the polyhydroxy compound having a hydrophilic group used in the present invention include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2-dimethylolbutyric acid, and 2,2-dimethylolvaleric acid. Etc. Carboxylic acid group-containing polyester polyols produced using these as part of the raw material can also be suitably used. Further, a polyester polyol having a sulfonic acid group introduced by 5-sulfoisophthalic acid, sulfoterephthalic acid, 4-sulfophthalic acid, or the like may be used. These polyhydroxy compounds introduced with hydrophilic groups are neutralized with at least one selected from organic amines such as ammonia and triethylamine and metal bases such as Na, K, Li and Ca, and then used as raw materials for prepolymers. You can also.

  Examples of the polyamine compound having a hydrophilic group used in the present invention include sodium 2- (2-aminoethylamino) ethanesulfonate, sodium salt of addition reaction product of 2-acrylamido-2-methylpropanesulfonic acid and ethylenediamine. Lysine, 1,3-propylenediamine-β-ethylsulfonic acid, and the like. Chain extension with these polyamine compounds having hydrophilic groups is carried out before emulsification.

  The amount of the polyhydroxy compound having a hydrophilic group or the polyamine compound having a hydrophilic group is such that the amount of the hydrophilic group contained in the aqueous polyurethane resin is 0.03 to 0.30 mmol, preferably 0. It is necessary to adjust so that it may become 05-0.15 mmol. When the hydrophilic group is less than 0.03 mmol, the dispersion stability of the aqueous polyurethane resin is insufficient and phase separation tends to proceed. On the other hand, if it exceeds 0.30 mmol, the average particle size becomes too small, the viscosity increases, it becomes difficult to sufficiently increase the resin solid content concentration, and the water resistance of the dried coating film may be further lowered. .

  In the synthesis of the prepolymer, the molar ratio of the total isocyanate groups derived from the polyisocyanate and the total hydroxyl groups derived from the polyhydroxy compound: NCO / OH is not particularly limited, but prevents poor dispersion and extends the chain with the polyamine compound. In order to prevent gelation, the range of 1.03 to 1.5 is preferable, and 1.05 to 1.4 is more preferable.

  When synthesizing the prepolymer, an organic solvent inert to isocyanate groups such as acetone, methyl ethyl ketone, acetonitrile, ethyl acetate, dioxane, tetrahydrofuran, etc. is added during or after the reaction in order to make the reaction proceed uniformly. Also good.

  The temperature range for the synthesis of the prepolymer is not particularly limited, but is preferably 30 to 120 ° C., more preferably 40 to 100 ° C., particularly in order to prevent an increase in the viscosity of the prepolymer and to sufficiently promote urethanization. Preferably it is 45-90 degreeC.

  The appropriate reaction time for obtaining the prepolymer depends on conditions such as the reaction temperature, but the prepolymer can be usually obtained by reacting for 0.1 to 10 hours.

  In the case where the prepolymer contains a hydrophilic group capable of forming a salt such as a carboxylic acid group or a sulfonic acid group, it is desirable to make it hydrophilic (neutralized) using a neutralizing agent. Examples of basic compounds that can be used as the neutralizing agent include inorganic bases such as sodium hydroxide, potassium hydroxide, and sodium carbonate, and tertiary compounds such as trimethylamine, triethylamine, triethylenediamine, dimethylaminoethanol, and N-methylmorpholine. Examples include amines and aqueous ammonia.

  There are no particular restrictions on the method of hydrophilization (neutralization), but (a) reaction with a neutralizing agent before, during or after synthesis of the prepolymer, (b) neutralization with water used during emulsification It can be carried out by adding an agent.

  Examples of the nonionic surfactant that can be used in the method for producing the aqueous polyurethane resin composition of the present invention include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene octylphenyl ether, and polyoxyethylene nonylphenyl. Polyoxyethylene alkyl phenyl ethers such as ethers, ethylene oxide adducts of acetylenic diol, polyoxyethylene derivatives, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, fatty acid monoglycerides, polyethylene glycol fatty acid esters, polyoxyethylene laurylamine, etc. Examples include oxyethylene alkylamine.

  Although there is no restriction | limiting in particular about the addition method of a nonionic surfactant, For example, it can implement by methods, such as adding (a) adding before emulsification, (b) adding with the water used during emulsification.

  The amount of nonionic surfactant used varies depending on the type of surfactant and the degree of hydrophobicity of the polymer, but is preferably 0.1 to 5% by weight, more preferably in the aqueous polyurethane resin composition of the present invention. 0.2 to 3% by weight. Moreover, as preferable HLB of a nonionic active agent, it is 12-20, More preferably, it is 14-17.

  The amount of water used in the emulsification is not particularly limited, but is preferably 25 to 120 parts by weight, more preferably 40 to 90 parts by weight, based on 100 parts by weight of the resin solid content. If the amount of water is less than 25 parts by weight relative to 100 parts by weight of resin solids, stirring may be difficult due to thickening, and if it exceeds 120 parts by weight, an appropriate resin solids concentration should be set. In order to obtain, it is necessary to distill off a large amount of water.

  The aqueous polyurethane resin in the present invention is desirably made high molecular weight by adding a chain extender before, during or after emulsification. The chain extender used in the present invention is water or a polyamine compound containing two or more primary or secondary amino groups, and has a high molecular weight by chain extension of the remaining isocyanate groups of the prepolymer. Can be achieved. Specific examples of the polyamine compound include ethylenediamine, diethylenetriamine, triethylenetetramine, hexamethylenediamine, xylylenediamine, metaphenylenediamine, piperazine, hydrazine, and adipic acid dihydrazide. The amount of polyamine used can be arbitrarily selected from 0.3 to 1.5 equivalents, preferably 0.4 to 1.2 equivalents, based on the terminal isocyanate group of the prepolymer.

  When the aqueous polyurethane resin composition contains a low-boiling organic solvent, it is desirable to distill off the solvent at 30 to 80 ° C. under reduced pressure. Moreover, it is also possible to adjust the resin solid content density | concentration in an aqueous polyurethane resin composition by adding or distilling water.

  The aqueous polyurethane resin composition of the present invention can also contain a crosslinking agent for the purpose of improving durability. Examples of the crosslinking agent include amino resins, epoxy compounds, aziridine compounds, carbodiimide compounds, oxazoline compounds, polyisocyanate compounds, and the like.

  Furthermore, the water-based polyurethane resin composition of the present invention contains additives that are usually used within a range that does not inhibit cohesion, such as plasticizers, tackifiers (rosin resin, rosin ester resin, terpene resin, terpene phenol resin petroleum Resin, coumarone resin, etc.), fillers, pigments, thickeners, antifoaming agents, antioxidants, ultraviolet absorbers, flame retardants, preservatives and the like.

  There is no restriction | limiting in particular as a manufacturing method of the film molding of this invention, Well-known techniques, for example, a salt coagulation method, a heat coagulation method, etc. can be mention | raise | lifted. As a substrate on which the aqueous polyurethane resin composition is applied or immersed, various conventionally known types such as porcelain, glass and metal can be used. It is also possible to dry after impregnating or applying to the fiber material substrate.

  The film thickness of the molded film of the present invention is not particularly limited because it varies depending on the application, but is preferably 10 to 1000 μm, more preferably 20 to 1000 μm, and particularly preferably 100 to 500 μm.

  The molded film of the present invention can be used, for example, as a glove, finger sack, condom, medical bag, leather-like sheet, catheter, O-ring and the like.

  The film molded product of the present invention exhibits excellent mechanical properties (elongation, tensile strength, low modulus) without using a crosslinking agent. The breaking strength is 25 MPa or more, preferably 30 MPa or more, the breaking elongation is 400% or more, preferably 500% or more, and the 300% modulus is 10 MPa or less, preferably 5 MPa or less (measurement conditions: distance between chucks 20 mm, pulling speed 100 mm / Min).

  In addition, the aqueous polyurethane resin composition of the present invention is less likely to swell when dried at room temperature or high temperature, and can form a smooth film. Therefore, it can be suitably used as a coating agent for various substrates. is there. As the coating method, for example, the coating can be performed by brushing, pouring, knife coating, spraying, spraying, spin coating, roll coating, or dipping, followed by drying by baking to room temperature or 200 ° C.

  The aqueous polyurethane resin composition of the present invention does not generate blisters or bubbles even when molded at a high temperature, so that a homogeneous film molded product can be obtained by a simple method.

  Hereinafter, the present invention will be described in detail with reference to examples, but the contents thereof do not particularly limit the scope of the present invention.

  Evaluation methods for the aqueous polyurethane resin composition of the present invention are as follows.

<Measurement method of average particle diameter>
The average particle size of the aqueous polyurethane resin composition was determined by measuring the particle size distribution using Microtrac UPA150 (manufactured by Nikkiso Co., Ltd.) to determine the volume average particle size.

<Method for preparing film>
An aqueous polyurethane resin composition is stretched on a PET film using a bar coater or an applicator, dried in an oven heated to a predetermined temperature (90 to 150 ° C.) for a predetermined time (5 to 15 minutes), and then the PET film. A film was prepared by peeling off the film.

<Evaluation of film properties>
A test piece was prepared from the film prepared above by punching with a JIS No. 3 dumbbell mold. Using the obtained test piece, the breaking strength, elongation at break, and 300% modulus of the film were measured with a tensile tester. The measurement conditions were a distance between marked lines of 20 mm and a pulling speed of 100 mm / min.

  The raw materials used in Examples and Comparative Examples are as follows.

PTMG1000: polytetramethylene ether glycol (PTG1000, manufactured by Hodogaya Chemical Co., Ltd., molecular weight 1000, OH value 112.8 mgKOH / g)
PTMG2000: Polytetramethylene ether glycol (PTG2000, manufactured by Hodogaya Chemical Co., Ltd., molecular weight 2000, OH value 56.5 mgKOH / g)
PPG2000: Polypropylene glycol (Sanix PP-2000, manufactured by Sanyo Chemical Industries, Ltd., molecular weight 2000, OH value 54.8 mgKOH / g)
2,2-dimethylolpropionic acid: manufactured by Tokyo Chemical Industry Co., Ltd. Neopentyl glycol: manufactured by Tokyo Chemical Industry Co., Ltd. trimethylolpropane: manufactured by Tokyo Chemical Industry Co., Ltd. 4,4′-diphenylmethane diisocyanate: Millionate MT, Nippon Polyurethane Industry Co., Ltd. Company-made isophorone diisocyanate: Tokyo Chemical Industry Co., Ltd. 1,6-hexamethylene diisocyanate: Tokyo Chemical Industry Co., Ltd. nonionic surfactant A: Polyoxyethylene lauryl ether (Nonion K-220, NOF Corporation make, HLB16.5)
Nonionic surfactant B: polyoxyethylene cetyl ether (Nonion P-210, manufactured by NOF Corporation, HLB 12.9)
<Synthesis of prepolymer>
PTMG2000, 300.0 parts by weight, was added to a reactor equipped with a stirring blade, a heating device and a reflux condenser, heated to 120 ° C., and dehydrated under reduced pressure for 60 minutes. After cooling to 80 ° C., 29.8 parts by weight of 1,6-hexamethylene diisocyanate was added and reacted for 3 hours. Subsequently, 5.3 parts by weight of 2,2-dimethylolpropionic acid, 22.5 parts by weight of neopentyl glycol, 82.3 parts by weight of 4,4′-diphenylmethane diisocyanate and 188.5 parts by weight of methyl ethyl ketone were added for 3 hours. The prepolymer no. 1 was synthesized. In the same manner, the prepolymer No. 1 was reacted with the formulation shown in Table 1. 2 to 13 were synthesized.

実施例１
表２に示すように、脱イオン水１４２．８重量部にトリエチルアミン２．１重量部、非イオン性界面活性剤Ａ３．２重量部を加え、この水溶液にＮｏ．１のプレポリマー３００．０重量部を攪拌しながら滴下し、乳化分散させた。続いて、１０％ピペラジン水溶液２０．０重量部（ピペラジンとして２．０重量部）を加えて、室温で３０分間攪拌することで鎖延長し、乳化液を得た。最後に、得られた乳化液を脱溶剤し、脱イオン水で調整して樹脂固形分濃度６０．０重量％の水性ポリウレタン樹脂組成物を得た。この水性ポリウレタン樹脂組成物の平均粒子径は０．６３μｍであった。

Example 1
As shown in Table 2, 2.1 parts by weight of triethylamine and 3.2 parts by weight of the nonionic surfactant A were added to 142.8 parts by weight of deionized water. 300.0 parts by weight of the prepolymer 1 was added dropwise with stirring and emulsified and dispersed. Subsequently, 20.0 parts by weight of a 10% piperazine aqueous solution (2.0 parts by weight as piperazine) was added, and the chain was extended by stirring at room temperature for 30 minutes to obtain an emulsion. Finally, the obtained emulsion was desolvated and adjusted with deionized water to obtain an aqueous polyurethane resin composition having a resin solid content concentration of 60.0% by weight. The average particle size of this aqueous polyurethane resin composition was 0.63 μm.

実施例１
＜フィルムの調製および評価＞
ＰＥＴフィルム上にアプリケータを用いて水性ポリウレタン樹脂組成物を延伸し、１３０℃に加熱したオーブン中で１０分間乾燥させた後、ＰＥＴフィルムからはく離することでフィルムＮｏ．１を調製した。得られたフィルムは表面が平滑であり、膜厚は１５０μｍであった。このフィルムの破断強度、破断時伸び率、３００％モジュラスはそれぞれ３２ＭＰａ、７００％、２．５ＭＰａであった。表３にフィルム調製条件、膜厚およびフィルム物性をまとめた。

Example 1
<Preparation and evaluation of film>
An aqueous polyurethane resin composition is stretched on an PET film using an applicator, dried in an oven heated to 130 ° C. for 10 minutes, and then peeled off from the PET film to remove film No. 1 was prepared. The obtained film had a smooth surface and a film thickness of 150 μm. The breaking strength, elongation at break, and 300% modulus of this film were 32 MPa, 700%, and 2.5 MPa, respectively. Table 3 summarizes the film preparation conditions, film thickness, and film properties.

実施例２
表２に示すように、Ｎｏ．２のプレポリマーおよびその他の化合物を使用した以外は、実施例１と同様にして水性ポリウレタン樹脂組成物を製造した。

Example 2
As shown in Table 2, no. An aqueous polyurethane resin composition was produced in the same manner as in Example 1 except that the prepolymer 2 and other compounds were used.

  According to the drying temperature, drying time and film thickness shown in Table 3, film No. 2-4 were prepared.

As shown in Example 3 to Example 13 and Reference Example Table 2, An aqueous polyurethane resin composition was produced in the same manner as in Example 1 except that 2 to 9 prepolymers and other compounds were used.

  According to the drying temperature, drying time and film thickness shown in Table 3, film No. 5-16 were prepared.

Comparative Examples 1-6
As shown in Table 2, Comparative Examples 1 and 2 are No. No. 2 prepolymer, Comparative Examples 3 to 6, An aqueous polyurethane resin composition was produced in the same manner as in Example 1 except that 10 to 13 prepolymers and other compounds were used. Among these, since the nonionic surfactant was not used in Comparative Example 1, the emulsion stability was low, and an aqueous polyurethane resin composition could not be obtained due to thickening. In Comparative Example 6, the amount of 2,2-dimethylolpropionic acid used in the prepolymer synthesis is as large as 19.5 parts by weight, so that the hydrophilic group contained in the aqueous polyurethane resin is 0.32 mmol with respect to 1 g of the resin solid content. As a result, since the average particle size of the emulsion was small, the viscosity was remarkably increased during emulsification, and an aqueous polyurethane resin composition could not be obtained. In Comparative Example 5, the amount of 2,2-dimethylolpropionic acid used during the synthesis of the prepolymer is as low as 1.2 parts by weight, so that the hydrophilic group contained in the aqueous polyurethane resin is 0. As a result, the emulsification stability was inferior because the hydrophilic group concentration was too low, and the resin solids settled.

  According to the drying temperature, drying time and film thickness shown in Table 3, film No. 17-19 were prepared. In Comparative Example 2, 125 parts by weight of deionized water was used for 100 parts by weight of resin solids during emulsification, so the resin solids concentration after desolvation was as low as 45.0% by weight. During film molding, blistering and bubble generation due to water evaporation are remarkable, and the appearance is remarkably inferior. In Comparative Example 3, the weight of diphenylmethane diisocyanate (4,4′-diphenylmethane diisocyanate) relative to the total polyisocyanate Since the ratio was low, diphenylmethane diisocyanate (4,4′-diphenylmethane diisocyanate) was not used in Comparative Example 4, so all the films prepared from these aqueous polyurethane resin compositions had noticeable blisters and bubbles and had an appearance. It was extremely inferior. Film No. Since the blisters and air bubbles of Nos. 17 to 19 were remarkable, the film physical properties could not be measured.

Claims (4)

An aqueous polyurethane resin composition comprising an aqueous polyurethane resin produced from a polyisocyanate and a polyhydroxy compound and a nonionic surfactant and having a resin solid content concentration of 50% by weight or more, wherein the aqueous polyurethane resin is An aqueous polyurethane resin composition characterized by satisfying the following conditions.
(A) 60 to 95% by weight of the polyisocyanate is diphenylmethane diisocyanate, and the remainder is aliphatic polyisocyanate or alicyclic polyisocyanate. (A) Anionic groups contained in the aqueous polyurethane resin are based on 1 g of resin solids. 0.03 to 0.30 mmol The aqueous polyurethane resin composition according to claim 1, wherein 30% by weight or more of the polyhydroxy compound is polytetramethylene ether glycol. A film molded article formed from the aqueous polyurethane resin composition according to claim 1 or 2. The film molding according to claim 3, wherein the film thickness is 10 to 1000 µm.