JP6703946B2 - Polyester resin, coating liquid and laminate - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polyester resin, a coating liquid containing the polyester resin, and a laminate formed by forming a coating film containing the polyester resin on a substrate.

Polyester resins such as polyethylene terephthalate and polybutylene terephthalate are widely used in various fields as materials for moldings such as fibers, films or sheets because of their excellent mechanical strength, thermal stability, hydrophobicity and chemical resistance. ing.

The polyester resin can have various structures and characteristics by appropriately selecting and polymerizing a combination of a dicarboxylic acid component and a glycol component as constituent components. A coating film formed by applying a polyester resin to various base materials has excellent adhesion to the base material, and this coating film also has excellent adhesion to other base materials. .. As described above, the formed coating film has excellent adhesion and adhesiveness, and thus the polyester resin is widely used in applications such as an adhesive, a coating agent, an ink binder, and a paint.

In recent years, when electronic parts are processed by roll-to-roll method, the adhesive is continuously applied on the plastic film unwound from the roll, and the film on which the adhesive coating film is formed is temporarily wound on the roll. While being unwound again, it is adhered to various adherends such as electronic parts. Thus, when the film having the adhesive coating formed thereon is once wound into a roll, the formed adhesive coating prevents contact with the coating and blocking of the wound film. There is a need. Usually, in order to prevent blocking, the adhesiveness of the adhesive is suppressed. However, in adhering to an adherend, it is necessary for the adhesive to sufficiently enhance the adhesiveness, and various measures have heretofore been made against such contradictory problems.

For example, in Patent Document 1, an adhesive containing a crystalline polyester resin having a glass transition temperature of −20° C. to 30° C., an amorphous polyester resin having a glass transition temperature of 40 to 90° C., and an organic solvent. Agent compositions are disclosed. This adhesive composition has excellent adhesiveness to a polyester film, tin-plated copper and electrolytic copper foil, and also has an excellent antiblocking effect, and is required to have adhesiveness to a metal such as a flexible flat cable. It is preferably used for various purposes.

However, the adhesive composition described in Patent Document 1 is intended to improve the adhesiveness and the anti-blocking effect as well as to improve the heat resistance, and therefore the coating film formed on the substrate is The bonding process with the adherend cannot be performed at a low temperature. That is, the adhesive composition described in Patent Document 1 is used for adhesion processing with an adherend at 130°C, and cannot be used for applications where adhesion processing is performed at a low temperature such as 70 to 100°C. It was

In recent years, cases in which electronic parts and the like having poor heat resistance are used as adherends are increasing, and it is necessary to perform bonding processing at a low temperature such as 70 to 100° C. on such adherends. .. Further, in order to reduce the cost at the time of bonding processing, there is an increasing demand for a polyester resin having excellent bonding processing properties at low temperatures. However, a polyester resin excellent in both antiblocking effect and adhesive processability at low temperature has not been proposed yet.

JP, 2009-84348, A

It is an object of the present invention to provide a polyester resin which has an excellent antiblocking effect as well as excellent adhesion processability at low temperatures, and a coating solution and a laminate obtained from the polyester resin.

As a result of intensive studies, the present inventor has found that a specific polyester resin can solve the above problems, and has reached the present invention.

That is, the gist of the present invention is as follows.
(1) A polyester resin (A) having a glass transition temperature of −10 to 40° C. and a heat of crystal fusion of less than 1 J/g,
A polyester resin (B) having a glass transition temperature of −40 to −10° C. and a melting point of 25 to 68° C.,
The weight ratio of both resins [(A) / (B)] is a 20 / 80-95 / 5 der Ru polyester resin,
The polyester resin contains at least three dicarboxylic acids selected from terephthalic acid, isophthalic acid, adipic acid, azelaic acid, and sebacic acid as dicarboxylic acid components, and ethylene glycol, butanediol, neopentyl glycol as glycol components. Containing at least three glycols selected from butyl ethyl propane diol, 2-methyl-1,3-propane diol, polyethylene glycol, polyoxyethylene bisphenol A ether, and polytetramethylene glycol,
The glass transition temperature of the polyester resin is −40 to 40° C.,
In the temperature-deformation amount curve measured by the softening temperature test method by thermomechanical analysis of JIS K7196, the number of inflection points is 2 to 7, and the maximum value of the temperature of the inflection point is 5 to 55°C. A polyester resin characterized by .
(2 ) A coating liquid comprising an organic solvent containing 5% by mass or more of the polyester resin described in (1 ) .
( 3 ) A laminate comprising a substrate and a coating film containing the polyester resin according to (1 ) formed on the substrate.
( 4 ) The laminated body according to ( 3 ), wherein the coating film on the base material is further laminated with another base material.

INDUSTRIAL APPLICABILITY The polyester resin of the present invention has an excellent anti-blocking effect, can be bonded to an adherend at a low temperature, and has excellent adhesive strength after bonding. For this reason, it can be used for an application in which an electronic component or the like having poor heat resistance is used as an adherend, and the cost at the time of bonding can be reduced.

It is a schematic diagram which shows the temperature-deformation amount curve measured by the softening temperature test method by thermomechanical analysis.

Hereinafter, the present invention will be described in detail.
The polyester resin of the present invention has a glass transition temperature of −40 to 40° C., and has a number of inflection points of 2 to 7 in the temperature-deformation amount curve measured by the softening temperature test method by thermomechanical analysis of JIS K7196. And the maximum value of the temperature at the inflection point is 5 to 55°C.

The polyester resin of the present invention needs to have a glass transition temperature (Tg) of −40 to 40° C., preferably −35 to 30° C., and more preferably −35 to 20° C. It is preferably −35 to 0° C., most preferably.
When the Tg of the polyester resin is less than −40° C., the anti-blocking effect is inferior. On the other hand, when the Tg of the polyester resin exceeds 40° C., the bonding process cannot be performed at a low temperature, and the bonding process can be performed even if the bonding process is performed. It is less powerful.

The polyester resin of the present invention has a number of inflection points of 2 to 7 in the temperature-deformation amount curve when the softening point is measured using a thermomechanical analyzer, and the maximum value of the temperature of the inflection point is 5 It must be ~55°C. By satisfying such a characteristic value, it is possible to exert an effect that it is excellent in the blocking prevention effect, that the bonding process can be performed at a low temperature, and that the bonding strength after bonding is also excellent.

In the present invention, the characteristic values as described above are obtained by using a polyester resin with a thermomechanical analyzer (“TMA2940” manufactured by TA Instruments), a load of 500 mN, a heating rate of 5° C./min, and a tip probe diameter. It is determined from the temperature-deformation amount curve when measuring the softening point by penetration measurement under the conditions of 1 mm, sample thickness 200 μm, and measuring temperature 0° C.
Since the inflection point is displayed as a peak in the differential chart of the temperature-deformation amount curve, the number of inflection points and the temperature are equivalent to the number of peaks and the peak top temperature in the differential chart. May be obtained using.
This will be described with reference to FIG. The one showing the temperature-deformation amount curve is 1, and the inflection point is shown by 3. The temperature-deformation amount curve 1 shown in FIG. 1 has three inflection points. The respective temperatures at the inflection points 3 are shown at 5 to 7, and the maximum value of the temperature at the inflection point is the temperature shown at 5. The minimum value of the temperature at the inflection point is the temperature shown by 7. The one showing the differential chart of the temperature-deformation amount curve is 2, and the one showing these peaks is 4.

Among them, the number of inflection points is preferably 2 to 4, and more preferably 2 to 3. When the number of inflection points of the polyester resin is less than 2, the effect of the present invention cannot be exhibited, and one or both of the blocking prevention effect and the adhesion processability at low temperature is inferior. Becomes On the other hand, when the number of inflection points exceeds 7, the adhesive strength of the polyester resin is lowered.

The maximum temperature of the inflection point is preferably 10 to 45°C, more preferably 13 to 35°C, and most preferably 17 to 30°C. When the maximum value of the inflection point is less than 5°C, the polyester resin is inferior in the blocking prevention effect, while when the maximum value of the inflection point exceeds 55°C, the bonding process is performed at a low temperature. Difficult to do.
Furthermore, the minimum value of the temperature of the inflection point is preferably −20 to 5° C., and more preferably −15 to 0° C. When the minimum value of the temperature of the inflection point is less than -20°C, the polyester resin tends to be inferior in the blocking prevention effect, and when the minimum value of the temperature of the inflection point exceeds 5°C, it is bonded at a low temperature. It is difficult to process.

The polyester resin of the present invention contains, as a dicarboxylic acid component, at least three dicarboxylic acids selected from terephthalic acid, isophthalic acid, adipic acid, azelaic acid and sebacic acid, and as a glycol component, ethylene glycol, butanediol, It is preferable to contain at least three glycols selected from neopentyl glycol, butylethylpropanediol, 2-methyl-1,3-propanediol, polyethylene glycol, polyoxyethylene bisphenol A ether, and polytetramethylene glycol.

In order to obtain the polyester resin of the present invention having the above characteristic values and compositions, it is preferable to contain the following two types of polyester resin (A) and polyester resin (B).

First, the polyester resin (A) will be described.
The polyester resin (A) is preferably composed mainly of a polycarboxylic acid component and a glycol component.
Examples of the polycarboxylic acid component constituting the polyester resin (A) include terephthalic acid, isophthalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, and undecane dicarboxylic acid. Acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, octadecanedioic acid, nonadecanedioic acid, eicosanedioic acid, docosanedioic acid, phthalic acid, naphthalenedicarboxylic acid, 4 , 4'-dicarboxybiphenyl, 5-sodium sulfoisophthalic acid, 5-hydroxy-isophthalic acid, fumaric acid, maleic acid, itaconic acid, mesaconic acid, citraconic acid, pyromellitic acid, trimellitic acid, oxalic acid, 1, Examples thereof include 4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 2,5-norbornenedicarboxylic acid, dimer acid, hydrogenated dimer acid, and the like, and anhydrides thereof. These may be used alone or in combination of two or more.
Among them, from the viewpoint of durability and the like, it is preferable to contain terephthalic acid and isophthalic acid as the polyvalent carboxylic acid component.
Further, in order to improve the adhesion processability at low temperature, it is preferable to contain an aliphatic dicarboxylic acid having a main chain of 4 to 18 carbon atoms, among which adipic acid (6 carbon atoms), azelaic acid (carbon number). 9), sebacic acid (10 carbon atoms) and dodecanedioic acid (12 carbon atoms) are preferably contained. When the above aliphatic dicarboxylic acid is used, the aliphatic dicarboxylic acid having 4 to 6 carbon atoms is 25 to 50 mol% and the aliphatic dicarboxylic acid having 7 to 10 carbon atoms is contained in all the acid components constituting the polyester resin (A). Is preferably 20 to 45 mol %, and the aliphatic dicarboxylic acid having 11 to 18 carbon atoms is preferably 10 to 40 mol %.

Examples of the glycol component constituting the polyester resin (A) include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polytetramethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6- Hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,4-cyclohexanedimethanol, 1,3- Cyclohexanedimethanol, tricyclodecanedimethanol, spiroglycol, dimerdiol, neopentylglycol, 2,2-butylethylpropanediol, 2-methyl-1,3-propanediol, 1,2-propanediol, polyoxyethylene Examples thereof include bisphenol A ether. These may be used alone or in combination of two or more.
Among them, ethylene glycol, neopentyl glycol and 1,2-propanediol are preferably contained as the glycol component from the viewpoint of solubility and the like.
In addition, since the same effect as that of the aliphatic dicarboxylic acid can be expected and the adhesion processability at low temperature can be improved, polyalkylene glycol such as polyethylene glycol, polytetramethylene glycol, polyoxyethylene bisphenol A ether, etc. It is preferable to contain 5 to 5 mol %.

As the polyester resin (A), those having the following constitutions can be preferably used.
-Terephthalic acid (20-60 mol%)/isophthalic acid (20-55 mol%)/sebacic acid or azelaic acid (20-45 mol%)/ethylene glycol (40-70 mol%)/neopentyl glycol (30-60 mol%)
-Terephthalic acid (20-55 mol%)/isophthalic acid (20-55 mol%)/adipic acid (20-50 mol%)/ethylene glycol (40-70 mol%)/neopentyl glycol (30-60 mol%)

The polyester resin (A) may contain, for example, a hydroxycarboxylic acid, an aliphatic lactone, a monocarboxylic acid other than the above-mentioned polyvalent carboxylic acid component and glycol component, as long as the effects of the present invention are not impaired. It may contain other monomer components such as monoalcohol. The copolymerization ratio of the other monomer components in the polyester resin (A) is preferably less than 50 mol% with respect to all the monomer components contained in the polyester resin (A).
As the hydroxycarboxylic acid, lactic acid, glycolic acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 2-hydroxyisobutyric acid, 2-hydroxy-2-methylbutyric acid, 2-hydroxyvaleric acid, 3-hydroxy Examples thereof include valeric acid, 4-hydroxyvaleric acid, 5-hydroxyvaleric acid, 6-hydroxycaproic acid, 10-hydroxystearic acid, 4-hydroxyphenylstearic acid and 4-(β-hydroxy)ethoxybenzoic acid.
Examples of the aliphatic lactone include β-propiolactone, β-butyrolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone and the like.
Examples of the monocarboxylic acid include lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, benzoic acid, p-tert-butylbenzoic acid and cyclohexanoic acid.
Examples of monoalcohols include octyl alcohol, decyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, and 2-phenoxyethanol.

The glass transition temperature of the polyester resin (A) is preferably −10 to 40° C., more preferably −5 to 30° C., and further preferably 0 to 20° C. When the glass transition temperature of the polyester resin (A) exceeds 40° C., it becomes difficult for the polyester resin composed of the polyester resin (A) and the polyester resin (B) to be bonded at low temperature. On the other hand, when the glass transition temperature of the polyester resin (A) is lower than −10° C., the polyester resin composed of the polyester resin (A) and the polyester resin (B) tends to be inferior in blocking prevention effect.

Further, the polyester resin (A) preferably has a heat of crystal fusion of less than 1 J/g. That is, the polyester resin (A) is preferably amorphous. When the polyester resin (A) has a crystal fusion heat amount of 1 J/g or more, the polyester resin composed of the polyester resin (A) and the polyester resin (B) has a crystallinity, so that the polyester resin (A) is bonded at a low temperature Is difficult to perform, and even if the bonding process can be performed, the bonding strength tends to be poor.

Next, the polyester resin (B) will be described.
In the polyester resin of the present invention, it is preferable that the polyester resin (B) contained together with the polyester resin (A) is also composed mainly of a polyvalent carboxylic acid component and a glycol component.

Examples of the polycarboxylic acid component constituting the polyester resin (B) include terephthalic acid, isophthalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, and undecane dicarboxylic acid. Acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, octadecanedioic acid, nonadecanedioic acid, eicosanedioic acid, docosanedioic acid, phthalic acid, naphthalenedicarboxylic acid, 4 , 4'-dicarboxybiphenyl, 5-sodium sulfoisophthalic acid, 5-hydroxy-isophthalic acid, fumaric acid, maleic acid, itaconic acid, mesaconic acid, citraconic acid, pyromellitic acid, trimellitic acid, oxalic acid, 1, Examples thereof include 4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 2,5-norbornenedicarboxylic acid, dimer acid, hydrogenated dimer acid, and the like, and anhydrides thereof. These may be used alone or in combination of two or more.
Among them, from the viewpoint of durability and the like, it is preferable to contain terephthalic acid and isophthalic acid as the polyvalent carboxylic acid component.
Further, in order to improve the adhesion processability at low temperature, it is preferable to contain an aliphatic dicarboxylic acid having a main chain having 6 to 12 carbon atoms, among which adipic acid (6 carbon atoms) and azelaic acid (carbon number). 9), sebacic acid (10 carbon atoms) and dodecanedioic acid (12 carbon atoms) are preferably contained. When using the said aliphatic dicarboxylic acid, it is preferable to contain 10-40 mol% of aliphatic dicarboxylic acid of carbon number 6-12 among all the acid components which comprise polyester resin (B), and carbon number 6-8. It is more preferable that the aliphatic dicarboxylic acid is contained in an amount of 20 to 40 mol %, and the aliphatic dicarboxylic acid having 9 to 12 carbon atoms is contained in an amount of 10 to 30 mol %.

Examples of the glycol component constituting the polyester resin (B) include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polytetramethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6- Hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,4-cyclohexanedimethanol, 1,3- Cyclohexanedimethanol, tricyclodecanedimethanol, spiroglycol, dimerdiol, neopentylglycol, 2,2-butylethylpropanediol, 2-methyl-1,3-propanediol, 1,2-propanediol, polyoxyethylene Examples thereof include bisphenol A ether. These may be used alone or in combination of two or more.
Among them, from the viewpoint of crystallinity, it is preferable to contain 1,4-butanediol as a glycol component. When 1,4-butanediol is contained, its content is preferably 50 mol% or more, and more preferably 70 mol% or more in the total glycol component constituting the polyester resin (B).
Further, in order to improve the adhesion processability at low temperature, it is preferable to contain 0.5 to 5 mol% of polyalkylene glycol such as polyethylene glycol, polytetramethylene glycol, polyoxyethylene bisphenol A ether and the like.

As the polyester resin (B), those having the following configurations can be preferably used.
-Terephthalic acid (15-50 mol%)/isophthalic acid (20-50 mol%)/sebacic acid or azelaic acid (10-30 mol%)/1,4-butanediol (96 mol% or more)
-Terephthalic acid (15-50 mol%)/isophthalic acid (20-50 mol%)/adipic acid (20-50 mol%)/1,4-butanediol (96 mol% or more)

In the polyester resin (B), if necessary, for example, a hydroxycarboxylic acid, an aliphatic lactone, a monocarboxylic acid, other than the above-mentioned polyvalent carboxylic acid component and glycol component, as long as the effect of the present invention is not impaired, Other monomer components such as monoalcohol may be contained. The copolymerization ratio of the other monomer components in the polyester resin (B) is preferably less than 50 mol% with respect to all the monomer components contained in the polyester resin (B).
As the hydroxycarboxylic acid, lactic acid, glycolic acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 2-hydroxyisobutyric acid, 2-hydroxy-2-methylbutyric acid, 2-hydroxyvaleric acid, 3-hydroxy Examples thereof include valeric acid, 4-hydroxyvaleric acid, 5-hydroxyvaleric acid, 6-hydroxycaproic acid, 10-hydroxystearic acid, 4-hydroxyphenylstearic acid and 4-(β-hydroxy)ethoxybenzoic acid.
Examples of the aliphatic lactone include β-propiolactone, β-butyrolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone and the like.
Examples of the monocarboxylic acid include lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, benzoic acid, p-tert-butylbenzoic acid and cyclohexanoic acid.
Examples of monoalcohols include octyl alcohol, decyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, and 2-phenoxyethanol.

The glass transition temperature of the polyester resin (B) is preferably −40 to −10° C., more preferably −35 to −16° C., and further preferably −35 to −22° C. When the glass transition temperature of the polyester resin (B) exceeds −10° C., it becomes difficult for the polyester resin composed of the polyester resin (A) and the polyester resin (B) to perform bonding processing at low temperature. On the other hand, when the glass transition temperature of the polyester resin (B) is lower than −40° C., the polyester resin composed of the polyester resin (A) and the polyester resin (B) tends to be inferior in the blocking prevention effect.

The polyester resin (B) preferably has a heat of crystal fusion of 1 to 10 J/g. That is, the polyester resin (B) is preferably crystalline. When the amount of heat of crystal fusion of the polyester resin (B) exceeds 10 J/g, the crystallinity becomes high, so that the solubility in the organic solvent becomes low, or the polyester resin (A) and the polyester resin (B) are combined. Adhesiveness of the constituted polyester resin decreases. On the other hand, when the heat of crystal fusion of the polyester resin (B) is less than 1 J/g, the polyester resin composed of the polyester resin (A) and the polyester resin (B) tends to have a poor blocking prevention effect.

The polyester resin (B) preferably has a melting point of 25 to 68°C, more preferably 30 to 66°C. When the melting point of the polyester resin (B) exceeds 68° C., the polyester resin composed of the polyester resin (A) and the polyester resin (B) may have poor adhesiveness at low temperatures. On the other hand, when the melting point of the polyester resin (B) is less than 25° C., the polyester resin composed of the polyester resin (A) and the polyester resin (B) may be inferior in blocking prevention effect.

The polyester resin (A) and the polyester resin (B) each have a number average molecular weight of preferably 2,000 to 35,000, more preferably 4,000 to 30,000, and further preferably 6,000 to 25,000. If the number average molecular weight of the polyester resins (A) and (B) exceeds 35,000, the solution viscosity when dissolved in an organic solvent becomes high, and even if the respective solutions are mixed, it becomes difficult to mix them uniformly. The coating solution obtained by mixing the solution of A) and the solution of the polyester resin (B) may be inferior in the adhesion processability at low temperature and the blocking prevention effect. On the other hand, when the number average molecular weight of the polyester resins (A) and (B) is less than 2000, the polyester resin composed of the polyester resins (A) and (B) has low adhesiveness when formed into a coating film. May be.

The mass ratio [(A)/(B)] of the polyester resin (A) and the polyester resin (B) is preferably 20/80 to 95/5, and more preferably 40/60 to 80/20. It is more preferably 40/60 to 60/40. If the mass ratio of the polyester resin (A) exceeds 95%, the adhesion processability at low temperatures may be poor. On the other hand, when the mass ratio of the polyester resin (A) is less than 20%, the antiblocking effect tends to be poor.

An important feature of the polyester resin of the present invention is that it has excellent adhesive processability at low temperatures. Usually, a polyester resin having a low glass transition temperature is used in order to obtain a polyester resin having excellent adhesion processability at a low temperature. However, the effects of the present invention cannot be obtained by simply using a polyester resin having a low glass transition temperature. That is, the polyester resin (A) and the polyester resin (B) having the above-mentioned properties are blended in a specific amount, and the characteristic value of the obtained polyester resin is set within the range specified in the present invention. It is possible to simultaneously satisfy the contradictory performances such as the blocking prevention effect and the adhesion processability at low temperature (70 to 100° C.).

In order to obtain the polyester resin (A) or the polyester resin (B) as described above, for example, the following method can be used. That is, after the raw material monomers such as polyvalent carboxylic acid and glycol are charged into the reaction can, the esterification reaction is carried out. Then, a polyester resin can be produced by polycondensation by a known method until the desired molecular weight is reached.
The esterification reaction is performed, for example, at a temperature of 180° C. or higher for 4 hours or longer.
The polycondensation reaction is generally carried out under reduced pressure of 130 Pa or less at 220 to 280° C. using a polymerization catalyst. Examples of the polymerization catalyst include titanium compounds such as tetrabutyl titanate, zinc acetate, magnesium acetate, metal acetates such as zinc acetate, antimony trioxide, hydroxybutyltin oxide, and organic tin compounds such as tin octylate. Be done. If the amount of the polymerization catalyst used is too small, the polymerization reaction may be delayed, while if it is too large, the color tone of the obtained polyester resin may be deteriorated. Therefore, the amount of the polymerization catalyst used is preferably 0.1 to 20×10 ⁻⁴ mol with respect to 1 mol of the acid component.
Then, in order to adjust the acid value of the polyester resin, it is possible to further add a polyvalent carboxylic acid after the polycondensation reaction and carry out the depolymerization reaction in an inert atmosphere.

The polyester resin of the present invention is a curing agent, a curing aid, a flame retardant, a heat stabilizer, an antioxidant, a lubricant, a pigment, a filler, a tackifier, another resin, within a range that does not impair the effects of the present invention. You may contain additives, such as an acid anhydride, an antistatic agent, and a foaming agent.

As the curing agent, epoxy resins, acid anhydrides, hexamethylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, xylylene diisocyanate, isocyanates such as dicyclohexylmethane diisocyanate and its blocked isocyanate, uretdiones, β-hydroxyalkylamide and the like can be mentioned. Examples of the curing catalyst include octyltin, triethylenediamine, triethylamine and the like.
Examples of the heat stabilizer include phosphoric acid and phosphoric acid ester. Examples of the antioxidant include hindered phenol compounds, hindered amine compounds, thioether compounds and the like.
Examples of the lubricant include talc, silica, polyethylene wax, paraffin wax and the like. Examples of the pigment include titanium dioxide, calcium carbonate, zinc oxide and the like. The tackifier may, for example, be a tackifier.
Examples of the flame retardant include halides such as decabromodiphenyl ether, bis(pentabromophenyl)ethane, tetrabromobisphenol, hexabromocyclododecane and hexabromobenzene, triphenyl phosphate, tricresyl phosphate, 1,3-phenylene bis( Diphenyl phosphate), ammonium polyphosphate, polyphosphoric acid amide, phosphorus compounds such as guanidine phosphate, halogen-containing phosphates such as tris(chloroethyl)phosphate, tris(dichloropropyl)phosphate, red phosphorus, triazine, melamine isocyanurate, ethylene dimelamine And nitrogen-based flame retardants such as tin dioxide, antimony pentoxide, antimony trioxide, aluminum hydroxide, magnesium hydroxide, and other inorganic flame retardant aids, and silicone powder.

The coating liquid of the present invention contains the polyester resin of the present invention in an organic solvent in an amount of 5% by mass or more.
As the organic solvent, toluene, xylene, solvent naphtha, aromatic solvents such as Solvesso, methyl ethyl ketone, methyl isobutyl ketone, ketone solvents such as cyclohexanone, methyl alcohol, ethyl alcohol, isopropyl alcohol, alcohol solvents such as isobutyl alcohol, Examples thereof include ester solvents such as ethyl acetate and normal butyl acetate, and acetate solvents such as cellosolve acetate and methoxyacetate. These may be used alone or in combination of two or more.
The content of the polyester resin in the coating liquid is preferably adjusted appropriately according to the application, and is preferably 20% by mass or more, and more preferably 30% by mass or more.

The laminate of the present invention has a coating film containing the polyester resin of the present invention described above formed on a substrate. In order to form a coating film on the surface of the base material, it is preferable to apply the coating liquid of the present invention.
In the laminate of the present invention, it is preferable that the coating film is uniformly formed over the entire surface of the substrate, but when the coating film is formed on a part of the surface of the substrate, for example, a dot-shaped or strip-shaped coating is applied. It is preferable to form the film on the surface of the base material substantially uniformly.
In the laminate of the present invention, the ratio of the coating film area to the substrate area can be appropriately adjusted according to the application. The smaller the proportion of the coating film area, the higher the blocking prevention effect of the laminate, but the adhesiveness tends to decrease. Therefore, considering adhesiveness, the ratio of the coating film area to the substrate area is preferably 20% or more, and more preferably 50% or more.
The coating film formed on the substrate preferably contains the polyester resin of the present invention in an amount of 70% by mass or more, and more preferably 80% by mass or more.
Examples of the substrate that constitutes the laminate of the present invention include a film or sheet made of a resin such as a polyester resin, a polycarbonate resin, or a polyvinyl chloride resin, or a metal foil such as an aluminum foil or a copper foil. As the base material, a material using a plurality of kinds of these films, sheets, metal foils and the like may be used.

The laminated body of the present invention may further have another base material laminated on the coating film formed on the base material. The coating film formed on the base material and the other base material can be adhered by heating or pressurizing as necessary.
The other substrate is not limited, and may be the same substrate as the substrate on which the coating film is formed or a different substrate.
Other substrates include polyethylene terephthalate, 1,4-polycyclohexylene dimethylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, polystyrene, polypropylene, polysulfone, aramid, polycarbonate, polyvinyl alcohol, cellophane, cellulose derivatives such as cellulose acetate. , Resin films and molded products such as polyethylene, polyvinyl chloride, nylon, polyimide, ionomers; woven and knitted fabrics, non-woven fabrics, glass cloth, condenser paper, paraffin paper, papers such as synthetic papers, composite materials including papers and non-woven fabrics, etc. A porous substrate having a gap of; a metal or the like. The other base material may be a material using a plurality of kinds of various materials as described above.

The method for producing the polyester resin and the coating liquid of the present invention will be described.
The polyester resin of the present invention can be produced by polymerizing the above-mentioned polyester resin (A) and polyester resin (B) and then melt-kneading them in a polymerization kettle or using an extruder. Further, it can be produced by dissolving each of the polyester resin (A) and the polyester resin (B) in an organic solvent and then mixing these solutions. As the organic solvent, those similar to the organic solvent forming the coating liquid can be used. Since the coating liquid of the present invention contains a polyester resin and an organic solvent, it is preferable to adopt the latter manufacturing method.
In addition, the coating liquid of the present invention is obtained by simultaneously adding and dissolving the polyester resin (A) and the polyester resin (B) in an organic solvent, or by melt-kneading the polyester resin (A) and the polyester resin (B). It can be produced by a method of dissolving the obtained polyester resin of the present invention in an organic solvent.

In the laminate of the present invention, a coating film can be formed on a base material by applying the coating liquid of the present invention on a base material and drying it as necessary to remove the organic solvent.
The method of applying the coating liquid onto the substrate is not particularly limited, and known methods such as reverse roll coating method, gravure coating method, die coating method, comma coating method or spray coating method can be used. ..

The coating film containing the polyester resin of the present invention has an excellent antiblocking effect. Therefore, a laminate in which a coating film formed by the coating liquid of the present invention is laminated on a base film, even if it is in a roll form, the coating film on the base film has a base material laminated thereon. It can be stored in roll form for a long period of time without adhering to the film.

Hereinafter, the present invention will be described more specifically by way of examples. The invention is not limited by these examples.

1. Measuring Method (1) Composition of Polyester Resin ¹ H-NMR measurement was carried out using an NMR measuring device (JNM-LA400 manufactured by JEOL Ltd.), and the composition of the polyester resin was determined from the peak intensity of each monomer component. Deuterated trifluoroacetic acid was used as the measurement solvent.

(2) Glass transition temperature (Tg), melting point (Tm), and heat of crystal fusion of polyester resin After aging polyester resin for 1 week at 25° C. or higher, according to JIS-K 7121, an input compensation type differential scanning calorimeter (Perkin Using a diamond DSC type manufactured by Elmer Co., Ltd., from a chart obtained by raising the temperature from −50° C. to 200° C. at 10° C./min, the midpoint between the two bending point temperatures derived from the glass transition is taken as the glass transition temperature (Tg). ) And the peak of the melting temperature at the time of temperature rise was taken as the melting point (Tm) of the polyester resin. Also, the heat of crystal fusion was calculated from the peak area of the melting temperature.

(3) Number average molecular weight of polyester resin Polyester in terms of polystyrene by GPC analysis using a liquid sending unit (LC-10ADvp type manufactured by Shimadzu Corporation) and an ultraviolet-visible spectrophotometer (SPD-6AV type manufactured by Shimadzu Corporation). The number average molecular weight of the resin was determined. As the GPC analysis conditions, the detection wavelength was 254 nm, and tetrahydrofuran was used as the solvent.

(4) Number of inflection points and temperature The obtained coating solution was coated on a Teflon (registered trademark) sheet, heat-treated at 60°C for 30 minutes to remove the mixed solvent, and then vacuum dried at 80°C for 24 hours. Then, a 200 μm thick coating film was formed on the Teflon sheet.
The formed coating film was peeled from the Teflon sheet, and using the coating film as a sample, a temperature-deformation amount curve was measured by a softening temperature test method by thermomechanical analysis of JIS K7196 (a schematic diagram of the temperature-deformation amount curve is shown in FIG. Shown in). The measurement was performed using a thermomechanical analyzer ("TAMA2940" manufactured by TA Instruments) with a load of 500 mN, a heating rate of 5°C/min, a tip probe diameter of 1 mm, a measuring temperature of 0°C, and a sample thickness of 200 µm. It was done under the conditions.
Then, the number of inflection points of the measured temperature-deformation amount curve and the temperature at the inflection point were read.

(5) Blocking prevention performance Using the obtained coating liquid, a polyester film (S-50 manufactured by Unitika Ltd., thickness 50 μm, inner surface corona treatment, outer surface non-corona treatment) was used, and 50% of the coating area was applied to the inner surface corona treated surface. After stacking the polyester films with holes formed in a grid pattern so that the resulting coating solution is obtained, a desktop coating device (Yasuda Seiki Co., Ltd. bar coater device, film applicator No. 542-AB type) is used. Applied. Then, the laminated polyester films were removed, heat treatment was performed at 100° C. for 30 seconds, and the mixed solvent was dried to obtain a laminate 1 in which a coating film having a thickness of 10 μm was formed on the substrate.
Then, on the coating film of the obtained laminated body 1, the outer surface non-corona-treated surface of a polyester film (S-50 manufactured by Unitika Ltd., thickness 50 μm, inner surface corona-treated, outer surface non-corona-treated) as another substrate was applied. Using a hot press machine (manufactured by Hayashi Kikai Seisakusho Co., Ltd.), a load of 0.1 MPa was applied in an atmosphere of 30° C. and 70% RH to bond them to obtain a laminate 2.
The laminate 2 was left standing in an atmosphere of 23° C.×50% RH for 24 hours, then cut into a length of 10 cm and a width of 25 mm, and a tensile strength tester (manufactured by Shimadzu Corporation Autograph AG100B type) was used to obtain a temperature of 23° C. A 180 degree peel test was performed in a constant temperature bath, the peel strength was measured, and an average value of 5 samples was calculated.
The antiblocking performance was evaluated according to the following four grades based on the peel strength value.
◎: Less than 0.1 N/25 mm ○: 0.1 N/25 mm or more, less than 1.0 N/25 mm △: 1.0 N/25 mm or more, less than 2.0 N/25 mm ×: 2.0 N/25 mm or more

(6) Adhesion workability at low temperature The laminate 1 having a coating film formed on the base material and the other base material produced in Examples and Comparative Examples were treated at temperatures of 70, 85, 100 and 120°C. The laminate 2 produced by pressing at a pressure of 0.2 MPa for 10 seconds under conditions of 24 hours left in an atmosphere of 23° C.×50% RH, and then cut into a length of 10 cm and a width of 25 mm, and a tensile strength tester. (Shimadzu Corporation Autograph AG100B type) was used to perform a 180 degree peel test in a constant temperature bath at 23° C., peel strength was measured, and an average value of 5 samples was calculated.
The peeling strength value was used to evaluate the adhesion processability at low temperature in the following four stages.
⊚: 20 N/25 mm or more ◯: 10 N/25 mm or more, less than 20 N/25 mm Δ: 5 N/25 mm or more, less than 10 N/25 mm ×: less than 5 N/cm In the present invention, the evaluation of Δ or more indicates practicality. It was judged that the product had the product, and the product having a cross was judged to have no practicality.
In each of the peeling tests at the pressing temperatures of 70° C. and 85° C., the evaluation of the adhesiveness being ⊚ or ◯ was judged to be sufficiently excellent in the adhesion processability at low temperature.

2. Preparation Example 1 of polyester resin
58 g (35 mol%) of terephthalic acid, 58 g (35 mol%) of isophthalic acid, 61 g (30 mol%) of sebacic acid, 42 g (67 mol%) of ethylene glycol, 71 g (68 mol%) of neopentyl glycol, and 0.4 g of tetrabutyl titanate as a polymerization catalyst. 1 g was charged into the reactor, and the inside of the system was replaced with nitrogen. Then, while stirring these raw materials at 1000 rpm, the reactor was heated at 245° C. to be melted. After the temperature inside the reactor reached 245° C., the esterification reaction was allowed to proceed for 3 hours. After 3 hours, the temperature inside the system was set to 250° C. and the inside pressure was reduced. After the inside of the system reached a high vacuum (pressure: 0.1 to 10 ⁻⁵ Pa), a polymerization reaction was further performed for 3.0 hours to obtain a polyester resin (A1).

Preparation Examples 2 to 26
The same operations as in Preparation Example 1 were performed except that the charging composition of the polyester resin was changed as shown in Tables 1 and 2 to obtain polyester resins (A2) to (A15) and polyester resins (B1) to (B11). .. Tables 1 and 2 show the charged composition of monomers, the final composition, and the resin properties of the polyester resins obtained in Preparation Examples 1-26.

The abbreviations in Table 1 and Table 2 are as follows.
TPA: terephthalic acid IPA: isophthalic acid ADA: adipic acid AZA: azelaic acid SEA: sebacic acid EG: ethylene glycol BD: 1,4-butanediol NPG: neopentyl glycol BEPG: 2,2-butylethylpropane propane MPD: 2 -Methyl-1,3-propanediol PEG1000: polyethylene glycol NEE: polyoxyethylene bisphenol A ether PTMG1000: polytetramethylene glycol

Example 1
A polyester resin composed of 60 parts by mass of the polyester resin (A1) and 40 parts by mass of the polyester resin (B1) was added to a mixed solvent of toluene and methyl ethyl ketone (toluene/methyl ethyl ketone=8/2 (mass ratio)), and a paint shaker was used. By shaking, a coating liquid containing 30% by mass of the polyester resin in the mixed solvent was prepared.
A polyester film (Unitika's S-50, thickness 50 μm, inner surface corona treated, outer surface non-corona treated) was used as a substrate, and a tabletop coating device (Yasuda The coating liquid was applied using a bar coater device manufactured by Seiki Co., Ltd., film applicator No. 542-AB type). Then, it heat-processed at 100 degreeC for 30 second(s), and dried the mixed solvent, and produced the laminated body 1 in which the 10-micrometer-thick coating film was formed on the base material.
Then, on the coating film of the obtained laminate 1, an inner corona-treated surface of a polyester film (S-50 manufactured by Unitika Ltd., thickness 50 μm, inner surface corona treatment, outer surface non-corona treatment) as another substrate was formed. Using a hot press machine (manufactured by Hayashi Kikai Seisakusho), the laminated body 2 in which other base materials were laminated was pressed under a pressure of 0.2 MPa for 10 seconds under each temperature condition of 70, 85, 100 and 120°C. It was made.

Examples 2-12, 14-24, 26, Comparative Examples 1-8 , Reference Examples 1-2
As shown in Tables 3 to 5, the same operation as in Example 1 was performed except that the types and contents of the polyester resins (A) and (B) were changed, and a coating liquid containing the polyester resin and a laminate were obtained. A laminate 2 in which 1 and other base materials were laminated was produced.

Examples 27-29
In Example 27, when the coating liquid is applied to the surface of the base material, a polyester film having holes in a lattice pattern is superposed on the base material to give a coating area of 20% of the area of the surface of the base material. As described above, a laminate 1 and a laminate 2 in which other base materials were laminated were produced in the same manner as in Example 1 except that the polyester film having holes in a lattice pattern was removed after the application. .. A laminate was prepared in the same manner as in Example 27, except that a polyester film having holes in a grid pattern was used so that the coating area was 50% in Example 28 and the coating area was 80% in Example 29. 1. A laminate 2 in which other base materials were laminated was produced.

Tables 3 to 5 show the characteristic values of the polyester resins produced in Examples, Comparative Examples , and Reference Examples , and the results of evaluating various characteristics using the laminate 2 in which other base materials are laminated.

The polyester resins of Examples 1 to 12, 14 to 24, and 26 to 29 have a glass transition temperature of -40 to 40°C, an inflection point number of 2 to 7, and a maximum inflection point temperature. Of 5 to 55° C., the blocking resistance was excellent and the adhesion processability at low temperature was excellent.
The polyester resin of Comparative Example 1 had a maximum inflection point temperature of less than 5° C., and thus was inferior in blocking prevention effect. In the polyester resins of Comparative Examples 2 to 5, the maximum value of the temperature of the inflection point exceeded 55°C, and in Comparative Example 5, the glass transition temperature also exceeded 40°C, so that the adhesion processability at low temperatures was poor. It was
The polyester resin of Comparative Example 6 had a glass transition temperature of less than −40° C., and thus was inferior in blocking prevention effect.
The polyester resins of Comparative Examples 7 and 8 had one inflection point, Comparative Example 7 was inferior in blocking prevention effect, and Comparative Example 8 was inferior in adhesive workability at low temperature.

1 temperature-deformation amount curve 2 derivative chart 3 inflection point 4 peak 5 maximum value of inflection point temperature 6 intermediate value of inflection point temperature 7 minimum value of inflection point temperature

Claims (4)

A polyester resin (A) having a glass transition temperature of -10 to 40°C and a heat of crystal fusion of less than 1 J/g;
A polyester resin (B) having a glass transition temperature of −40 to −10° C. and a melting point of 25 to 68° C.,
The weight ratio of both resins [(A) / (B)] is a 20 / 80-95 / 5 der Ru polyester resin,
The polyester resin contains at least three dicarboxylic acids selected from terephthalic acid, isophthalic acid, adipic acid, azelaic acid, and sebacic acid as dicarboxylic acid components, and ethylene glycol, butanediol, neopentyl glycol as glycol components. Containing at least three glycols selected from butyl ethyl propane diol, 2-methyl-1,3-propane diol, polyethylene glycol, polyoxyethylene bisphenol A ether, and polytetramethylene glycol,
The glass transition temperature of the polyester resin is −40 to 40° C.,
In the temperature-deformation amount curve measured by the softening temperature test method by thermomechanical analysis of JIS K7196, the number of inflection points is 2 to 7, and the maximum value of the temperature of the inflection point is 5 to 55°C. A polyester resin characterized by. A coating liquid containing the polyester resin according to claim 1 in an amount of 5% by mass or more in an organic solvent. On a substrate, a laminate characterized by comprising formed coating film containing a polyester resin according to claim 1. The laminated body according to claim 3 , wherein the coating film on the base material is further laminated with another base material.

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