JPS5841994A - Paper coating composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a coating composition for paper, and the purpose thereof is to improve ink transfer properties, have high P (1 hour water resistance), and coated paper with good water resistance. An offset rotary press f61.l with extremely low formaldehyde generation and poor coloring properties.
It is an object of the present invention to provide a coating composition for paper that provides excellent performance as a coated paper for printing, such as good blistering resistance.

It is conventionally known to manufacture coated paper by applying a paper coating composition containing an aqueous binder or one other auxiliary agent such as a pigment to a paper substrate and providing a coating layer on the paper surface.
At this time, various waterproofing agents are used for the purpose of imparting water resistance to the coating layer.

However, recent advances in paper coating technology and printing technology have been remarkable, and efforts are being made to increase the speed of coating and printing in order to save labor and streamline the process. Particularly in the field of coated paper, there has been a remarkable increase in the use of lesium carbonate as a pigment added to coating compositions in order to conserve energy and resources. With the spread of offset rotary printing and the diversification of coated paper, various performances have come to be required of coated paper, and many countermeasures have been proposed, such as modifying the aqueous binder component and improving auxiliary components. In other words, for coated paper, improvements in printing ink transferability, halftone dot reproducibility, water resistance, and blister resistance in off-wheel printing are more desired than ever.

Water resistance (wet strength) can be effectively improved by, for example, increasing the amount of aqueous binder component relative to the pigment, but on the other hand, there are drawbacks such as a decrease in ink transfer during printing, and there is no effective method. Currently, as a means to improve this problem, a method is currently being used that involves adding a water-resistant agent as an auxiliary component.A typical water-resistant agent in this case is a water-based binder. However, while all of the previously used or proposed water resistance agents have effective advantages, at the same time they do not have important deficiencies.

For example, melamine-formaldehyde initial condensates have insufficient transferability of printing ink on coated paper, and when the pH of the coating composition is high, the water resistance effect is insufficient, and free formaldehyde from coated paper There were problems such as the generation of a large amount of (unfavorable in terms of work hygiene).In addition, the reaction product of polyamide polyurea and formaldehyde alone has an excellent effect on improving the transferability of printing ink on coated paper, and has excellent water resistance. It has the advantage that the amount of free formaldehyde generated from the coated paper is small. It is inferior.

Further, dialdehydes such as glyoxal cause coloring of coated paper, deteriorate water resistance over time, and have poor effects on improving printing ink transferability. Polyvalent metal salts such as zirconium significantly increase the viscosity of the coating solution, resulting in poor workability. Furthermore, the r-ton-formaldehyde initial condensate is inferior in hydrodynamic effect and effect on improving transferability of printing ink.

For this reason, the present inventors have developed a paper that has excellent water resistance when the pH of the coating composition is high, is free from the various drawbacks mentioned above, and has an extremely excellent effect of improving ink transfer during printing. As a result of intensive studies to develop a coating composition for paper, a coating composition for paper containing an aqueous solution of a thermosetting resin produced by a specific method as a water-resistant agent satisfied the above objectives, and It was discovered that this method has excellent effects, leading to the present invention.

That is, in the paper coating composition 1ζ containing an aqueous binder and a water-resistant agent, urea and a polyalkylene polyamine are subjected to a deammonia reaction as a water-resistant agent, and then a dibasic carboxylic acid and a dehydrated A polyamide polyester obtained by condensation, dehydration condensation with dibasic carboxylic acid, and deammonia reaction with urea,
The present invention provides a paper coating composition using an aqueous thermosetting resin solution obtained by reacting shrimp 7N lohydrin and formaldehyde in an aqueous solution.

The polyalkylene polyamine used in the present invention has two primary amino groups and at least one secondary amino group in the molecule.
A polyalkylene polyamine having a class amino group,
For example, diethylenetriamine, triethylenetetramine, tetraethylene penne, fiminobisprobylamine, 8-azahexane-1,6-diamine, 4.7-
Examples include cyazadecane-1,10-diamine. These polyalkylene polyamines can be used not only alone but also as a mixture of two or more.

Further, dibasic carboxylic acids used in the present invention include aliphatic carboxylic acids such as succinic acid, glucuric acid, arepic acid, sebacic acid, maleic acid, and fumaric acid, isophthalic acid, and terephthalic acid. Mention may be made of aromatic carboxylic acids and mixtures thereof.

Epihalohydrin used in the present invention includes epichlorohydrin, ebibromohydrin, etc., and epichlorohydrin is particularly preferred.

The polyamide polyurea of the present invention 1 is a polyamide polyurea (hereinafter referred to as polyamide polyurea) obtained by subjecting urea and polyalkylene polyamine to a deammoniation reaction, followed by dehydration condensation with a dibasic carboxylic acid, and further deammoniation reaction with ζ-urea. It is a polyamide polyurea (hereinafter referred to as polyamide polyurea (B)) obtained by dehydration condensation of polyurea (referred to as -1) or polyalkylene polyamine and dibasic carboxylic acid, and then deammonia reaction with urea. .

In the polyamide polyurea (A) 1ζ, the molar ratio of urea and poly-, realkylene polyamine is preferably around 1:2.

The reaction temperature is 100-200℃, preferably 120-170℃
℃ is appropriate, and the reaction is allowed to proceed for 2 to 8 hours while removing the generated ammonia from the system. Next, 1 mole of polyalkylene polyamine is subjected to dehydration condensation with 0.8 to 1.2 moles of dibasic carboxylic acid. Reaction temperature 120~
The reaction is carried out at 250° C., preferably 140° C. to 200° C., for 2 to 10 hours while removing produced water from the system.

The condensation reaction product thus obtained is reacted with Saraba ζaxillary element. The amount of urea is 0.2 to 1.5 moles, preferably 0.5 to 1.1 moles, per mole of secondary amino groups in the raw material polyalkylene polyamine. The reaction temperature is 1
The reaction temperature is 00 to 180°C, preferably 120 to 150°C, and the reaction is carried out at this temperature for 1 to 5 hours while removing one portion of generated ammonia from the system. In this way, polyamide polyurea (A) is obtained.

In the polyamide polyurea CB), the reaction between the polyalkylene polyamine and the dibasic carboxylic acid is carried out at a temperature of 120
The reaction is carried out at a temperature of -250°C, preferably 140-200°C, for 2-10 hours while removing generated water from the system. The reaction is carried out at a molar ratio of 1.4 to 8.0 mol, preferably 1.8 to 2.5 mol, of the polyalkylene polyamine per 1 mol ζ of the dibasic carboxylic acid. The dehydration condensation reaction product thus obtained is then reacted with urea. The amount of urea used is 0.2 to 1.0 mol, preferably 0.4 to 1.0 mol, per 1 mol of amino groups in the raw material polyalkylene polyamine.
It is 0.8 mol. The reaction temperature is 100 to 180°C, preferably 120 to 150°C.

The reaction is carried out while removing the ammonia that is generated from the system for 1 to 5 hours at a temperature of 6. As a method of preparing 6-urea, it is possible to charge the required amount all at once and allow the reaction to take place, or to charge a part of the required amount and remove the ammonia. After the reaction is completed, it is also possible to charge the remaining wire elements and perform the deammonification reaction. In this way, polyamide polyurea CB)
is obtained.

The polyamide polyurea obtained by straining as described above is dissolved in water and reacted with epihalohydrin and formaldehyde. The reaction order is: 1. Polyamide polyurea and epihalohydrin are reacted, and then formaldehyde is reacted. 2. Polyamide polyurea and formaldehyde are reacted, and then epihalohydrin is reacted. (2) The object of the present invention can be achieved by any method in which shrimp 710 hydrin and formaldehyde are reacted simultaneously.

However, the reaction with formaldehyde is -
It is preferable to carry out the reaction under acidic conditions, or once under alkaline conditions, and then further under acidic conditions.

The reaction of polyamide polyurea with epihalohydrin and formaldehyde is carried out in an aqueous solution with a concentration of 20 to 70% by weight, preferably 80 to 60%, at a reaction temperature of 80 to 80°C.
It will last for ~15 hours. The reaction with epihalohydrin is p
Although the reaction with formaldehyde can be carried out in a wide pH range such as H3 to H12, the reaction with formaldehyde is preferably carried out at a pH of 7 or below.
The reaction is carried out after adjusting the pH from 1 to 1 to 6.5, such as hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, etc., or the reaction is carried out under alkaline conditions such as pH 7 to 12, and then the pH is adjusted. 7 or less, preferably pH 8-6.5
The reaction is continued by adjusting the amount by 0.02 to 0.8 mol, preferably 0.04 to 0.2 mol, per mol of amino group in the amine. In addition, per mole of total urea used in the production of polyamide polyurea, 0.
(16-1 mol of formaldehyde, preferably 0.1-1 mol)
0.6 mol of formaldehyde are used.

In this way, an aqueous thermosetting resin solution that can be used in the present invention 1ζ can be obtained.

The paper coating composition of the present invention is prepared in exactly the same manner as the conventional method except for using the thermosetting resin aqueous solution specified by the present invention as a water-resistant agent, but the paper coating composition of the present invention can effectively exhibit its effects. Therefore, the thermosetting resin aqueous solution usually has a solid content of 0.8 to 2 parts by weight per 100 parts by weight of the aqueous binder (@type part).
Contains 0 heavy Tobu.

In addition, the aqueous solution used in the thermosetting agent 1 of the present invention is sufficiently effective as a water-resistant agent alone, but in some cases, it is also possible to replace a part of it with another water-resistant agent. be.

As the aqueous binder used in preparing the paper coating composition of the present invention, conventionally known aqueous binders can be used as they are.

Examples of such aqueous binders include water-soluble binders such as dekibun, oxidation hebun, modified starch, chilled cellulose, soybean protein, styresorbent resin, vinyl acetate resin, ethylene-vinyl acetate resin, methyl Examples include water emulsion and dispersion type binders such as methacrylate resins.

The paper coating composition of the present invention includes, in addition to the thermosetting resin aqueous solution and aqueous binder, pigments, dispersants, thickeners, thinners, antifoaming agents, foam suppressants, preservatives, antifungal agents, Flow control agents, release agents, coloring agents such as dyes and pigments, special performance imparting agents such as conductive agents, etc. may be added as necessary, and the effects of the present invention will not be hindered.

Examples of pigments include kaolin clay, talc, titanium dioxide, aluminum hydroxide, calcium carbonate,
Examples include inorganic pigments such as satin white and barium sulfate, and organic pigments whose main components are styrene and urea.
These may be used alone or in combination of two or more in any proportion.

Further, other conditions for adjusting the S degree e of the coating composition of the present invention can be adjusted by conventional methods in exactly the same manner as conventional methods, and there are no particular limitations. For example, the required amount of the thermosetting 1fi1411# aqueous solution of the present invention may be blended in advance with an adhesive component such as a water emulsion, a dispersion binder, a water-soluble binder, or a pigment slurry, or in any order other than e. It can be blended with

The thermosetting ml aqueous solution of the present invention was added to STIRESORB 5! Pre-blending a water emulsion or dispersion binder such as diene resin or methyl methacrylate resin allows the coating composition to be easily adjusted, and the stability of the coating composition is extremely excellent. This is the most preferable method in that it is easy to obtain coating results, and it is also possible to preferably obtain crushed paper, which is the object of the present invention.

The paper coating composition of the present invention can be prepared by conventionally known methods, such as blade coater, air dryer, roll coke, size press coat, cast coke, etc. Coating on a paper substrate, drying as required using normal methods,
Furthermore, coated paper can be produced by subjecting the paper to a super calender, machine calender, or other treatment, if necessary.

The paper coating composition of the present invention has excellent coating liquid stability without color shedding (significant thickening of the composition, agglomeration of pigments, etc.), and when coated on a paper substrate. The coated paper obtained by this process has excellent water resistance in the coated layer, produces significantly less formaldehyde, has excellent ink transfer properties, and has no coloration, and has excellent blister resistance in rotary offset printing. It has various excellent features that make it even more effective.

The present invention will be explained below with reference to Examples.

Example 1 (Preparation of 11 thermosetting resin aqueous solution In a four-eye flask equipped with a thermometer, reflux condenser, and stirring bar, 292 fc2 moles of triethylenetetramine) and 60 ml of urea were added.
F (1 mol) was charged and the reaction was carried out at 145-150°C for 4 hours while removing the generated ammonia from the system. Then, adipic acid 1465' (1 mol) was added and 15
Linearization reaction was carried out at 0 to 155°C for 5 hours. After cooling to 120°C, 24 Of (4 moles) of urea was added, and ammonia removal reaction was carried out at 125 to 180°C for 2 hours.

After step e, 180 t of water was gradually added to obtain an aqueous solution of polyamide polyurea.

After adding 87% formalin (202.5 tc 2.5 mol) and adjusting the pH by 5 I with concentrated hydrochloric acid, it was heated to 65°C.
The mixture was stirred and kept warm for 4 hours.

Next, 87j' (0.4 mol) of epichlorohydrin and 86 t of water were added, and the mixture was stirred at 60° C. for 8 hours. After e, the mixture was cooled to 25C to obtain a thermosetting resin aqueous solution with a solid content of 80%.

Example 2 Four solo flasks equipped with a thermometer, reflux condenser, and stirring bar.
diethylenetriamine (206 tc2 mol), water 10
F and adipic acid 146f (1 mol) were charged, and 150
The temperature was raised to ℃. Then, while distilling off the water produced,
After incubating at 150-155℃ for 6 hours, cooled to 180C, charged with 240fC4 mol of urea,
Nine 8-hour flash ammonia reactions were carried out while removing 1ζ of ammonia generated at 0C from the system. After 7, water 48゜t
was gradually added to obtain an aqueous solution of polyamide polyurea.

To the obtained polyamide polyurea aqueous solution, 55.5 f (0.6 mol) of epichlorohydrin and 800 f of water were added, and the mixture was stirred at 65° C. for 5 hours while keeping it warm. Next, 129.6f (1.6 mol) of 87% formalin was added and diluted with concentrated hydrochloric acid (
After adjusting the pH to 4, the mixture was stirred at 70° C. for 8 hours using a trowel. After cooling to 80°C, 30% caustic soda aqueous solution -
The pH was adjusted to 6+C to obtain an aqueous thermosetting resin solution with a solid content of 40%.

(2) Preparation of coating composition for paper Adding a pre-gelatinized oxidized starch aqueous solution and styrene-butydiene latex to a pre-dispersed pigment slurry, and further adding the thermosetting resin aqueous solution as a water resistant agent, A paper coating composition was prepared by mixing well.

The blending ratio (solid content weight) is as shown in Table 1, and the composition is
The solid content was adjusted to 1 so that it became 9.5 in H, and the solid content was adjusted to 55%.

The obtained paper coating composition exhibited smooth fluidity without any color sheak upon addition of the thermosetting 11Hj aqueous solution.

The viscosity and pH of the coating composition and the viscosity after being left for one day were
Shown in the table.

Table 1 These compositions were prepared using coach-in-blond, 86Y
One coat of base paper was coated on both sides with a dry solid content of 15 f/m on one side, and then dried with hot air at 120°C for 2 seconds.

After conditioning the humidity (20°C, 65% RH), apply one coat of this coated paper to a super calender (60'C160kQ/cm, 2 passes) to create a test sample, and apply various test methods 1.
The evaluation was made based on this. The results are shown in Table 2.

Comparative Example 1 Using the same apparatus as Example 1, triethylenetetra:/
292f (2 mol) and urea 60f (1 mol) were charged at 145 to 150°C, and the generated ammonia was removed from the system.
The reaction was carried out for 4 hours while removing ζ, and then adipic acid 146F (1%) was added and a 54-pass condensation reaction was carried out at 150-155°C. After cooling to 120C, urea 24
Add 0t (4v-le) and heat to 125-180℃ for 2 hours and 1f.
A fl deammonification reaction was performed. After that, water 1850
I got 1F.

Next, add 202.5 t (2.5 mol) of 87% formalin and adjust the pH with a trowel with concentrated hydrochloric acid.
The mixture was stirred and kept warm at ℃ for 4 hours. Then cool to 30℃,
The pH was adjusted to 81 using a 30% caustic soda aqueous solution S to obtain a thermosetting resin aqueous solution with a solid content of 30%.

Using this aqueous thermosetting resin solution, a coating composition for paper was strained in the same manner as in Example 1.2, and coated paper was produced in the same manner.

The resulting coated paper was tested for performance in the same manner as in Example 1.2, and the results shown in Table 2 were obtained.

Comparative Example 2 Substitute for thermosetting resin aqueous solution 1) + this violet resin 6
A coating composition for i-Koshi C paper was prepared in the same manner as in Example 1.2, except that 18 (melamine-formaldehyde Ff14 fat, manufactured by Seitomo Kagaku Kogyo Co., Ltd.) was used, and a coated paper was prepared in the same manner.

Comparative Example 8 A paper coating composition was prepared in the same manner as in Example 1.2 except that glyoxazine was used instead of the thermosetting resin aqueous solution, and a thin coated paper was prepared in the same manner.

Comparative Example 4 A paper coating composition was prepared in the same manner as Example 1.2 except that no water-resisting agent was used, and coated paper was prepared in the same manner.

For the coated papers obtained in Comparative Examples 2 to 4, Example 1.2
Similar performance tests were conducted and the results shown in Table 2 were obtained.

(8) Test Spraying Method The coated paper was conditioned for 48 hours at a temperature of 20° C. and a humidity of 65% (R) 1, and then subjected to measurement test spraying.

0 pH of the coating liquid using a glass electrode 1ilj pH meter, measurement temperature 20O Viscosity of the coating liquid using a B-type viscometer, rotation speed 6Q rpm, measurement.

Water resistance of 0 coating at a degree of 20℃ (a) Wet 'Rub method: Pour ion exchange water of about 0.1 MIM onto the coated surface,
The amount of elution was determined with the naked eye by rubbing it with a fingertip 7 times and transferring the amount of elution onto a sheet of black paper.

The evaluation criteria bottle was subjected to the following steps.

Water resistance (poor) 1 to 5 (excellent) (o) Using a Wet Pick method RI test 1 tester (Mei Seisakusho #), wet the coated surface with a water supply roll 1 and then print. The falling off and damage state was visually observed and judged. The criteria is Wet
This is the same as the R11b method.

Constant spray of formaldehyde from 0-corrupt paper J18L-10
41 Liquid phase extraction method (2) Acetyl acetone method (1) For formaldehyde measurement, measure by sealing a polyethylene bag to prevent migration and dispersion from other sources.
C provided.

Printing was performed in the following manner using the ink transferability RI test method for Ot paper, and the ink transferability was observed and determined with the naked eye.

The evaluation criteria were (1) 5-1 (poor).

(b)　　　　A　Method Print after adding a drop of water to the ink being mixed.

(C2) Method After moistening the surface to be coated with a water supply roll, print. (c) C method A combination of methods A and A above will also be printed.

White discoloration and heat-resistant white discoloration of coated paper The white discoloration of coated paper before and after heating in a hot air dryer at 150°C for 80 minutes was determined by measuring the B value using a Hunter reflectance meter in accordance with JI8P-8128+. It was tested by

The higher the number, the better the Murakuro discoloration.

0iIff4 Print on both sides of coated paper using off-circle ink using a blister property R1 tester, and after adjusting the humidity, soak in a heated silicone oil bath to determine the lowest temperature at which blistering occurs. shows.

Example 8 (1) Production of thermosetting resin aqueous solution Reactor similar to Example 2 - ζ, diethylenetriamine 108fT1 mol), triethylenetetramine 146f
(1 mol), water 2Of and mixed dibasic carboxylic acid 100f (0.77 mol as dibasic carboxylic acid) consisting of 122% succinic acid, 64% lucidic acid, and 14% adipic acid. , dehydration condensation was carried out at 160 to 165°C for 8 hours. Next, urea 240F (4 mol) was charged and deammonization was carried out at 145 to 150'C for 4 hours, after which water 410F was gradually added to obtain a polyamide polyurea aqueous solution.To this, 87% formalin 97 was added.
．． 2 f (1,2 mol), epicro? Rehydrin 129
．． Prepare 5F (1.4 mol) and water 960f to 30%
After adjusting the pH to lO with aqueous caustic soda solution, 6
After stirring while keeping warm at 5°C for 8 hours, the pH was adjusted to 4 with one trowel of 85% hydrochloric acid, and the mixture was stirred while keeping warm at 50°C for 4 hours. After the reaction was completed, the mixture was cooled to 80° C., and the pit was adjusted to 5.51ζ using an 80% caustic soda aqueous solution to obtain a thermosetting resin aqueous solution with a solid content of 80%.

(2) Preparation of coating composition for paper A pre-gelatinized oxidized starch aqueous solution; Add the above thermosetting @ fat aqueous solution as a water resistant agent;
Paper coating compositions having the blending ratios shown in Table 1 were prepared. still,
The composition was adjusted by adding electric water so that the solid content concentration was 11% by weight.

Table 8 Comparative Example 5 1 Violet Resin 61 instead of thermosetting resin aqueous solution
A coating composition for paper was prepared in the same manner as in Example 8 except that B was used.

Comparative Example 6 A paper coating composition was prepared in the same manner as in Example 8 except that glyoxal was used instead of the thermosetting resin aqueous solution.

Comparative Example 7 A paper coating composition was prepared in the same manner as in Example 8, using an aqueous solution of oxidized starch at 10% by weight as a paper coating composition.

(8) Preparation of coated paper These paper coating compositions were coated with size press coke.
The coated paper was coated with high quality paper of 185 F/Wl using ζ, air-dried, and then cured (hot plate) at 110° C. for 1 minute to obtain a coated paper.

Humidify this coated paper (temperature 20℃, humidity 65% Ru, 48℃)
After that time, measurement test 1 was carried out.

The results are shown in Table 4.

(4) Test Method O Stability of Coating Solution The coating solution was stored at a total temperature of 50° C. for 20 hours, and changes in the coating solution were observed.

O-blocking test paper was moistened with a trowel for 24 hours at 40°C and 80% IL H, then overlapped, and the pressure machine 1ζC temperature was 50°C.
, and a pressure of 1 kq/-·ζ for 2 hours, and the state of adhesion and the state of damage to the paper surface when peeled off were visually observed and judged.

Blocking property IF) 5-1 (poor) O Water resistance Ion exchange main fishing 0.1 st was dropped on the surface of the coated paper, rubbed 7 times with a fingertip, and the dissolution state of the coating composition was measured by the touch of the fingertip and the dissolution. Judging from the thing, \'s black paper, and \'s transition party.

Water resistance (f) 5-1 (poor) Quantification of formaldehyde from O-coated paper Same as Example 1.2.

Whitening and heat resistance of O-coated paper Same as Example 1.2.

Before procedural amendments (voluntary) July 2, 1980 Commissioner of the Japan Patent Office Shima 1) Haruki Tono1, Indication of the case 1981 Patent order No. 13grz6 No. 2, Title of invention Coating composition for paper 3, Amendment Relationship with the case of a person who does
209) Sumitomo Chemical Co., Ltd. Representative Sat
Takeshi 4, Agent Address: 5-15 Kitahama, Higashi-ku, Osaka, Showa
Month/Day (→Prior to procedural amendment (spontaneous) 6 February 1980 Ashiya, Commissioner of the Patent Office Shima 1) Haruki ■, Indication of the case 1982 Patent application No. H3872f No. 2, Name of the invention Togo### ＠φ Medical Treatment Coating Seiyamono 3, Relationship with the case of the person making the amendment Address of M person for patent purposes 5-15 Kitahama, Higashi-ku, Osaka Name (
209) Sumitomo Chemical Co., Ltd. Representative Hijikata
Formula % Formula % 5, Column 6 of the detailed description of the invention in the specification subject to amendment, Contents of the amendment (1) "0. 8 to 1.2 mole” is replaced with “0
．． 8 to 0.7 mol".

that's all

Claims (1)

[Claims] In a paper coating composition containing an aqueous binder and a water-resistant agent, urea and a polyalkylene polyamine are subjected to an ammonia reaction as the water-resistant agent, and then dehydrated and condensed with a dibasic carboxylic acid. A polyamide polyurea obtained by further reacting urea with ammonia. This patented paper coating composition uses a thermosetting aqueous solution obtained by reacting ene-4'hydrin and formaldehyde in an aqueous solution.