SI9600092A

SI9600092A - Process for the preparation of the coating mixture for the improvement of the moistness of the surface of paper and cardboard

Info

Publication number: SI9600092A
Application number: SI9600092A
Authority: SI
Inventors: Gabrijela Novak; Zdenka Kampus-Penic
Original assignee: Inst Za Celulozo In Papir Ljub
Priority date: 1996-03-15
Filing date: 1996-03-15
Publication date: 1997-10-31

Abstract

Predmet izuma je postopek za pripravo premazne mešanice za izboljšanje omočljivosti površine papirja in kartona z vodo in vodnimi lepili. Postopek rešuje problem posebnega medsebojnega lepljenja papirjev in kartonov z lepili na osnovi vode, kot je na primer med drugim tudi lepljenje setov samokopirnega papirja in temelji na dodajanju in uporabi asociativne hidrofobno modificirane etoksilirane emulzije na bazi uretana, ki v alkalnem mediju nabreka. Dodajanje omogoča doseganje nižjih kotov omakanja in s tem boljše proniciranje lepila v papir ter boljše držanje papirjev v setu med seboj.The subject of the invention is a method for preparing a coating mixtures for improving surface wettability paper and cardboard with water and water adhesives. Process solves the problem of special bonding water - based paper and paperboard, such as na an example is the bonding of copier sets paper and is based on the addition and use of associative hydrophobically modified ethoxylated emulsions based on urethane which swells in the alkaline medium. Adding makes it possible to reach lower dipping angles and thus better penetration of adhesive into paper and better adhesion of papers in a set with each other.

Description

POSTOPEK ZA PRIPRAVO PREMAZNE MEŠANICE ZA IZBOLJŠANJE OMOČLJIVOSTI POVRŠINE PAPIRJA IN KARTONAPROCEDURE FOR PREPARATION OF COATING MIXTURE FOR IMPROVEMENT OF THE PAPER AND CARTON SURFACES

Predmet izuma je postopek za pripravo premazne mešanice za 20 izboljšanje omočljivosti površine papirja in kartona z vodo in vodnimi lepili. Postopek rešuje problem posebnega medsebojnega lepljenja papirjev in kartonov z lepili na osnovi vode, kot je na primer med drugim tudi lepljenje setov samokopirnega papirja. Izum spada v razred D 21 HThe subject of the invention is a process for the preparation of a coating mixture for improving the wettability of the surface of paper and paperboard with water and aqueous adhesives. The process solves the problem of special bonding of papers and cartons with water-based adhesives, such as, among other things, the bonding of sets of copier paper. The invention belongs to class D 21 H

01/10 mednarodne patentne klasifikacije.01/10 international patent classification.

Tehnični problem, ki ga predloženi postopek po izum uspešno rešuje, je priprava premazne mešanice, ki bo nanešena na papir ali karton izboljšala njuno omočljivost tako, da bo dosežen nižji kot omakanja z vodo (npr. kot omakanja od 50-60°), ki omogoča dobro vpijanje lepila v papir.A technical problem that is successfully solved by the present invention is the preparation of a coating mixture that will be applied to paper or paperboard to improve their wettability so as to achieve a lower wetting angle (e.g. 50-60 ° wetting angle) allows the adhesive to be well absorbed into the paper.

Tehnični problem je znan na primer pri proizvodnji setov samokopirnega papirja. V bloku samokopirnih papirjev so z lepilom pritrjeni posamezni seti, pri čemer je set ponavadi sestavljen iz prednjega lista, vmesnih listov in zadnjega lista. Pri odtrganju posameznega seta samokopirnih papirjev naj bi se set držal skupaj, posamezni seti pa naj io bodo med seboj zlepljeni tako, da jih bo mogoče enostavno ločiti.A technical problem is known, for example, in the production of copier sets. In the block of self-copy papers, individual sets are attached with glue, with the set usually consisting of a front sheet, intermediate sheets and a back sheet. When tearing off each set of copy paper, the set should be held together and the individual sets should be glued together so that they can be easily separated.

Pri uporabi lepil na vodni osnovi je v smislu dobrega prijemanja lepila zelo pomembna površinska energija, oziroma kot omakanja površine papirja z vodo. Le-ta mora biti visok (npr. 95-115°) na prednji površini prvega lista in na zadnji površini zadnjega lista v setu. Na površinah vseh is srednjih listov in na zadnji površini prvega lista in prednji površini zadnjega lista pa naj bo kot omakanja nižji. Z izpolnitvijo teh zahtev je dosežena primerna adhezija za lepilo, ki pri lepljenju setov, zaporedno zloženi v blok, pronica med liste v posameznem setu in jih zlepi. Lepilo pa ne sme pronicati in močno zlepiti sete med seboj - to je npr. zadnji list zgornjega in prvi list spodnjega seta, saj sicer setov med seboj ne moremo enostavno ločiti (oddvojiti).When using water-based adhesives, surface energy, or wetting of the paper surface with water, is very important in terms of good adhesion of the adhesive. It should be high (eg 95-115 °) on the front surface of the first leaf and on the back surface of the last leaf in the set. On the surfaces of all the middle leaves and on the back surface of the first leaf and the front surface of the last leaf, keep the dipping angle lower. By meeting these requirements, a suitable adhesive for adhesive is achieved which, when glued together, folded together in a block, seeps between the sheets in each set and glues them together. However, the adhesive must not penetrate and strongly adhere the set to each other - that is, e.g. the last sheet of the upper set and the first sheet of the lower set as otherwise the sets cannot be easily separated.

Pri proizvodnji samokopirnega papirja je bil doslej dosežen primeren kot omakanja površine papirjev s pripravo premazne mase različnih kombinacij, ki dajejo zadovoljive rezultate. Pomanjkljivost pa so precej velika nihanja pri istem papirju oziroma še bolj pri različnih proizvodnih serijah istega papirja in pri različnih osnovnih papirjih.In the production of self-copy paper, a suitable angle of wetting of the surface of the papers has been achieved so far by preparing a coating of various combinations that give satisfactory results. The drawbacks, however, are quite large fluctuations in the same paper, or even more so in different production batches of the same paper and in different underlying papers.

Reševanje zastavljenega problem poizkušajo reševati na različne načine, kar je mogoče zaslediti tudi iz literature (npr. Dobler, F. und Nink, G.: Spezifische Anforderungen fCir das Streichen von Selbstdurchschreibepapieren: Theoretische (Jberlegungen undThey try to solve the problem in various ways, which can also be traced from the literature (eg Dobler, F. und Nink, G.: Spezifische Anforderungen fCir das Streichen von Selbstdurchschreibepapieren: Theoretic (Jberlegungen und

Praxisergebnisse, PTS Streicherei-Symposium 1995, Munchen, 12,15.09.1995). Kot ena izmed možnih rešitev se kaže sintetizirani lateks, ki io bi - premazan na papirju - vplival na znižanje kota omakanja z vodo.Praxisergebnisse, PTS Streicherei-Symposium 1995, Munich, September 12, 1995). One of the possible solutions is synthesized latex, which, if coated on paper, would have the effect of lowering the angle of wetting.

Trenutno ta rešitev še ni komercialno dosegljiva.Currently, this solution is not yet commercially available.

Postopek za pripravo premazne mešanice za izboljšanje omočljivosti površine papirja in kartona z vodo po izumu temelji na dodajanju in uporabi asociativne hidrofobno modificirane etoksilirane emulzije na bazi is uretana, ki v alkalnem mediju nabreka, ter na ta način omogoča doseganje nižjih kotov omakanja in s tem boljše pronicanje lepila v papir ter boljše držanje papirjev v setu med seboj.The process for the preparation of a coating mixture for improving the wettability of the surface of paper and paperboard with water according to the invention is based on the addition and use of associative hydrophobically modified ethoxylated emulsion based on is urethane, which swells in alkaline medium, thereby achieving lower wetting angles and thus better penetration of the adhesive into the paper and better holding the papers in the set with each other.

Bistvo postopka po izumu temelji na pripravi premazne mešanice z dodatkom emulzije in sicer pri pigmentnih premaznih masah v količini 0,1The essence of the process according to the invention is based on the preparation of a coating mixture with the addition of emulsion, in the case of pigment coatings in an amount of 0.1

- 1,0 utežnih % emulzije a.s./pigment a.s. (a.s.= absolutno suh) oziroma pri nepigmentnih premaznih masah v količini 0,1 - 2,0 utežnih % emulzije a.s/premazno maso a.s.. Delež dodatka je priporočljivo prilagoditi željenemu kotu omakanja papirne površine. Emulzijo med mešanjem dodajamo že pripravljeni premazni masi in sicer na koncu postopka priprave premazne mase. Ker so običajno premazne mase pripravljene v alkalnem mediju (pH = 8,0 - 8,5) ni potrebno dodajanje alkalij. Po dodatku emulzije pride do povečanja viskoznosti premazne mase in to premo sorazmerno s količino dodatka. Ker se pri višjih strižnih hitrostih viskoznost zniža, premazovanje take premazne mase običajno na premaznem stroju ne dela težav.- 1.0 wt.% Emulsion a.s./pigment a.s. (a.s. = absolutely dry) or in the case of non-pigmented coatings in an amount of 0.1 - 2.0% by weight of a.s emulsion / a.s coating weight. It is advisable to adjust the proportion of the additive to the desired wetting angle of the paper surface. During mixing, the emulsion is added to the already prepared coating material at the end of the coating preparation process. Since the coatings are usually prepared in an alkaline medium (pH = 8.0 - 8.5), no addition of alkali is required. The addition of the emulsion results in an increase in the viscosity of the coating mass, which is proportional to the amount of additive. As the viscosity decreases at higher shear rates, the coating of such a coating mass is usually no problem on the coating machine.

V nadaljevanju bo podan primer uporabe emulzije pri proizvodnji samokopirnega papirja in sicer v premazni masi z mikrokapsulami. Po io običajni recepturi proizvajalca je bila sestavljena premazna masa A. Sestavljena je bila tudi premazna masa B in sicer tako, da se standardni premazni masi na koncu doda 0,4 utežnih % emulzije a.s./premazno maso a.s.. Obe premazni masi sta bili nato po standardnem postopku nanešeni na štiri različne osnovne papirje. Vsem premazanim papirjem je bil is določen kot omakanja.The following will give an example of the use of an emulsion in the production of self-copy paper, coated with microcapsules. Following the usual manufacturer's recipe, coating A was assembled. Coating B was also made up by adding 0.4% by weight of emulsion ace / coating ace to the standard coating mass. standard procedure applied to four different basic papers. All coated papers were designated as wetting.

Tabela 1 prikazuje rezultate določanja kota (po standardu TAPPI 458) na štirih različnih osnovnih papirjih, premazanih s premazno maso A brez dodatka in premazno maso B z dodatkom emulzije.Table 1 shows the results of the angle determination (according to TAPPI 458) on four different base papers coated with an uncoated coating A and coated emulsion coated B.

Vrsta papirja Kot omakanja Kot omakanja pri premazni masi A pri premazni masi BPaper Type Wetting Angle Wetting At Coating A At Coating B

Štev.1 Number 1 67 67 60 60 Štev. 2 Num. 2 68 68 54 54 Štev. 3 Num. 3 58 58 48 48 Štev. 4 Num. 4 69 69 57 57

Legenda:Legend:

A = premazna masa brez dodatkaA = coating mass without additive

B = premazna masa CB z dodatkom 0,4 utežnega % emulzije a.s./premazno masoB = coating mass of CB with the addition of 0.4 wt% emulsion a.s./coating mass

a.s. (CB - coated back premazna masa)a.s. (CB - coated back coating)

Nižji kot omakanja z vodo pomeni boljšo omočljivost. Rezultati v tabeli io kažejo znižanje kota omakanja, kar pomeni boljšo omočljivost z vodo in vodnimi lepili na površini vseh štirih papirjev, ki so bili premazani s premazno maso B, ki ji je bila dodana emulzija.A lower wetting angle means better wettability. The results in Table io show a decrease in the wetting angle, which means better wettability with water and water adhesives on the surface of all four coats of B-coated paper to which the emulsion was added.

S pričujočim postopkom po izumu je mogoče izboljšati lastnosti premazanega papirja in kartona za lepljenje z vodnimi lepili, kar je is uporabno tako za samokopirni papir, kot tudi za druge vrste papirjev in kartonov, ki jih je potrebno lepiti z vodnimi lepili. Dodatek emulzije je po izumu mogoče uporabljati kot regulator za doseganje boljše omočljivosti (nižjega kontaktnega kota) papirja.The present method of the invention can improve the properties of coated paper and paperboard for bonding with water adhesives, which is useful for self-copy paper as well as for other types of paper and cardboard to be bonded with water adhesives. The emulsion additive according to the invention can be used as a regulator to achieve better wetting (lower contact angle) of paper.

S tem izumom je poleg omenjenega izboljšanja omočljivosti papirne površine podana tudi razširjena uporabnost hidrofobno modificirane 5 etoksilirane emulzije na bazi uretana, ki v alkalnem mediju nabreka, kar doslej še ni bilo poznano in uporabljeno.In addition to the aforementioned improvement of the wettability of the paper surface, the present invention also extends the widespread usefulness of a hydrophobically modified urethane-based ethoxylated 5 ethoxylated emulsion which swells in the alkaline medium, which has not yet been known and used.

Claims

1. A process for preparing a coating mix for improvement

5 wettability of the surface of the paper and cardboard, characterized in that, during mixing, an associatively hydrophobically modified urethane-based ethoxylated emulsion, which swells in the alkaline medium, is added to the coating mass.

2. A process for preparing a coating mixture for improving the wettability of a paper and cardboard surface according to claim 1, characterized in that an emulsion is added to the coating mixture in pigment coatings and in an amount of 0.1 - 1.0% by weight of emulsion as / pigment as. , depending on the desired wetting angle.

3. A process for preparing a coating mixture for improving the wettability of a paper and paperboard surface according to claim 1,

2o, characterized in that an emulsion is added to the coating mix for non-pigmented coatings in an amount of 0.1 - 2.0% by weight of the emulsion a.s. / coating weight a.s., depending on the desired wetting angle.

4. A process for preparing a coating mixture for improving the wettability of a paper and cardboard surface according to claims 1 to 3, characterized in that, in the manufacture of the paper sets, the coating mass B affects the property of the 5 surface of the paper so that it can adhere individual sheets in an individual set. , while the sets are not stuck together.