CA1324704C - Paperboard and packing paper production process - Google Patents

Abstract

The invention relates to a process for manufacturing wrapping paper and cardboard in which, before the sheet is formed, is added to the suspension containing the cellulose fibers (a) between 0.5 and 5 parts of cationic starch. per 100 parts of fibers, (b) polychloride of aluminum and optionally (c) a bonding agent. This process makes it possible to obtain products having good mechanical properties. This process also makes it possible to reduce the suspended matter in the water collected under the filter cloth during the formation of the sheet and to obtain greater productivity of the paper machine and better internal cohesion.

Description

'. '' 132 ~ 704 ~

PROCESS FOR THE MANUFACTURE OF PACKAGING PAPER AND CARDBOARD

The present invention relates to a process for manufacturing the papler.
and more particularly the packaging papler and the carton. -.
The raw paper pulp consists es ~ entirely of flbres of cellulose is formed in the form of an aqueous suspension which is diluted brought into the head box of the paper machine from where it is distributed on a filtering sheet on which the sheet of papler. This leaf is then dried and pulsed dried. The qualltés and the properties of the paper obtained are determined in particular by:
operating conditions for the paper machine, the raw pulp, the different additive annuities that we have in the suspenslon before the formation of the sheet and also the products that we layer on the sheet of papler - ~
after the filtering tolle. ., The present invention relates more specifically to products that we have ~ out before the formation of the sheet. . "-,: -The main quallté sought for packaging is the stress, It can also be interesting to make the paper resistant to moisture.
dity. Cellulose fibers come from unpainted raw pulp often recycled paper or cardboard, perfumes mixed with s, ~:
raw dough.
British patent GB 2,015,614 describes a process for manufacturing the umballago paper and grooves in the cardboard in which we add. ~:
the su ~ fiber board, before the calsse de tête, of the amlon catlonl- ~
that and a basal polychlorosulphate of aluminlum, or sulphate of aluminum nlum. The amount of catalytic starch does not exceed 0.4% of the weight of cellulose fibers. We know that catlonic starch contrlbue à la -mechanical resilience of the papler and 11 would be useful to be able to put much more than 0.4 Z in the suspension and especially to retain this starch in the formed sheet. Starch is very hydrophilic and if we exceeds a quantity of 0.5 Z we can no longer form the sheet of. ~
papler on the filtering sheet otherwise by greatly reducing the producti- -of the paper machine. According to the present invention, we have found a new process that allows the use of quantities of a ~ ldon superior 0.5 Z rowers in the head of the machine.
The present lnventlon is a manufacturing process of the papler packing and cardboard caract ~ rise to this ~ u 'we add s ~ par ~ ment to the suspension ~,. . .
'.

~ 3247 04 containing cellulose fibers before the sheet is formed ~
a) more than 0.5 part of cationic starch per 100 part ~ of -cellulose fibers, - -b) poly aluminum chloride The suspension containing the cellulose fibers can be raw or blanched dough, or a mixture of raw dough and white dough -shits. Very often we have ~ used paper and cardboard at previous mixture.
The cationic starch is a mixture of one or more of their products marketed under the generic name of catlonic starch. These products ..
are for example those described in ~ IRK OT ~ MER, 3rd edition, Vol. 21 ~.
page 503. The quantity is advantageously between 0.5 and 5:
partles per 100 partles of flbres ~ of cellulose, and preferably between 0.7 and 2.
Al ~ nium polychloride disintegrates the so-called products usually "aluminum polychloride", "Basque polychloride aluminum "," basic polychlorosulfate tialuminlum "and preferably one or more of the following products ~
l / the salt of formula:: ~;

n () m 3n-m (I). ~
'',. '..:
in which n is any, 3n- ~ is posltlf, m ot n being no ~ bres cntlers posltifs; said salt may also contain.
polyvalent anion Y cholsl among the anlons of sulfuric acldes, phosphoric, polyphosphoric, slllclques, chromic, carbo ~ yliques and sulfonic, the molar ratio Y being preferably understood Al between 0.015 and 0.4. .

2 / the salt of formula:

Aln (OH ~ mCl3n_m_2k (S04) k (II) where k, m and n are positive, 3n> m + 2k, the baslclté m / 3n is compressed between 0., 3 and 0.7 and k / n 8 0 ~ Ol to 0.3. This prodult can be prepared according to the process described in the patent - ~
US 3,929,666;

3 / the salt of formula:

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- 132 ~ 704 ~

[ln (H) 3n_m_2pClm (S4) p] z (III) in which (3n-m-2p) / 3n = 0.4 to 0.7; p = 0.04 to 0.25n; m / p = 8 at ~ -35; k, m, n and p are whole numbers and 2 is at molns 1. This ~ -prodult is described in patent GB 2,128,977;

4 / basic aluminum chlorosulfate of formula:: ~

AlnOHm (sO4) kcl3n- ~ -2k (IV) ~ `;
"'.', ''. ' in which the baslclté or the molar ratio m3 x l00 is understood between 40 Z approximately and 65 X approximately and in that it presents a report equl ~ nearly Al / éqùlvalent Cl comprls between 2.8 and 5, a ~ molecular asse ~ apparent -lalre ~ A measured by scattering of classlque light and apparent hydrotynamic diameters 0Z and 0W measured by diffuslon quasl-elastlque of the light of sulvantes values MA ~ 7000 _ 35000:
O:.
~ Z (A) 350 - 2500 A., ',''.,,.' ,.
0W (A) ~ 200 - l200 This product is certified in the French patent PR 2,584,699.
The quantity of polychloride t'aluminlum expressed as A12O3 at Use is advantageously a shareholder for 100 parts of cellulose and pr ~ erence flbres comprlse between 0.02 and 0.3 partle ~.
Blen that we pulsate to ~ outer products a and b in an order any place anywhere before the headbox of the macbine to papler, we prefer to ~ outer the polycbloride of aluminlum after cationic starch. It is also preferred that polyaluminum chloride ~ oit has ~ outed as close as possible to the headbox.
One can also a ~ outer in the suspension of cellulose fibers before the formation of the sheet and in addition to products a and b, other products such as dyes.
According to another embodiment of ~ ation of the invention, one can a ~ outer in addition to the cationic starch, one or more products chosen from polyacrylamides, polyethyleneimines, carboxymethylcellulose, urea-formaldehyde resins, melamine-formaldehyde resins, resins '.' `, ',.:` `,' .,:,.
: ~ ``:.

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132,470 ~ ~

amlnopolyamlde-épichlorhydrine, polyam resins ~ de-épichlorhydrine.
Advantageously we util ~ se these products in addition to catlonic starch and in the same quantities.
It is also possible according to another embodiment of the invention, in addition to products a and b or in addition to the products that we have with cationic starch such as polyacrylamides and others previously cited, a ~ outer bonding agent to make the paper a little hydro-phulph lul to resist humidity.
Although any bonding sgent is suitable, advantageously uses rosin or a mixture of one or more of their products chosen by ~ i the ketene timk slkyls and their derivatives, phospha-your fluorides, the anhydrides of fatty chain carboxylic acids, certain polyurethanes, styrene / maleic anhydride copolymers.
It is preferred to use the dimeric ketene alkyls and anhydrides carbosylic acids. ~ the amount to use depends on the pro-sought properties of paper or cardboard. Advantageously the quantity is less than 10 parts per 100 parts of cellulose fibers and preferably between 0.1 and 2 parts.
Preferably the bonding agent is a ~ outé before the polychloride of aluminum.
You can also add in the suspenslon, before the formation of the leaf; usual additives such as dyes, etc.
U ~ another advantage of lnventlon, ~ n plus two properties m ~ caDlquo ~ obte ~ uos, is a strong tlmlnutlon of ~ pending matters do ~ in le8 water ~ collected under the filtering sheet during the leaf foroat ~ on.
Another benefit of lnventlon is higher productivity ~ paper ~ achine and an internal cohesion mellleure; All these advantage ~ will appear ~ aans the examples. The following examples illu8 trent lnventlon.
~ '',.

EXEHPLE I (not in accordance with the invention) - Co ~ posltion in headbox 100 Z old paper Bonding agent: Alkyl ketene di ~ era 0.15 parts - Operating characteristics of the paper machine:
Flat table lalze utlle: 2.6 m "','' AT

i32 47 0 4: ~
~ `
Gram ~ age: 190 g / m2 Type of paper: cover for corrugated cardboard ~:
Treatment after format of the sheet: spraying ~
native starch on the surface. -:
We have ~ cationic starch, 1.4 parts per 100 parts of fibers.
Machine speed: 163 m / min ~ total coverage: 79%
Mullen burst rate: 2.75 (according to afnor standard N ~ Q 03053) p ~ (in headbox): 7.2 (EX ~ MPLE 2 (conforms to the invention) We operate as in Example 1, but we have ~ more in addition, before the calsse de tête, a polyvinyl chloride in proportlon of 0.15 partles expressed as Al2O3 per 100 parts of cellulose fibers.
We obtain:
Machine speed: 200 ~ / min Total ketentlon: 85%; :
Mulle ~: 3.09: ~
p ~ (in headbox): 7.2 _ E ~ eMPlE 3 ~ Confor ~ e à lnventlon) -r., 4 ~ p ~ 0 ~ operates as in example 2 mals a ~ outing 0.16 partle of. -:
aluminum polychloride ~ lnium com ~ e in Example 2 per 100 parts of ~ flbre of cellulose, we obtain:
Speed of delivery: 220 ~ / min Total retention: 85%
Mullen: 2.96 p ~ (in head): 7.2 .
In the whole of the descriptive memory and of the claims;
cations, the ~ partiesa to which reference is made; ~
are expressed by weight. ~ ~
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Claims (11)

1. Method of manufacturing wrapping paper and cardboard, characterized in that the suspension is added separately containing cellulose fibers before formation of the leaf:
a) more than 0.5 part by weight of cationic starch for 100 parts of cellulose fibers; and b) poly aluminum chloride. 2. Method according to claim 1, characterized in that we add, in addition to a and b, a bonding agent. 3. Method according to claim 1, characterized in that b is a basic aluminum polychlorosulfate. 4. Method according to claim 1, 2 or 3, characterized in that the amount of a is between 0.5 and 5 parts by weight per 100 parts of cellulose. 5. Method according to claim 1, 2 or 3, characterized in that the amount of a is between 0.7 and 2 parts by weight per 100 parts of cellulose. 6. Method according to claim 1, 2 or 3, characterized in that the amount of b expressed as Al2O3 is less than 1 part per 100 parts of cellulose. 7. Method according to claim 1, 2 or 3, characterized in that the amount of b expressed as Al2O3 is between 0.02 and 0.3 part by weight per 100 parts cellulose fibers. 8. Method according to claim 2, characterized in that the bonding agent is chosen from alkyls dimer ketenes and anhydrides of carboxylic acids. 9. Method according to claim 2 or 8, charac-terized in that the amount of bonding agent is less than 10 parts by weight per 100 parts of fiber cellulose. 10. The method of claim 2 or 8, charac-terized in that the amount of bonding agent is included between 0.1 and 2 parts per 100 parts of fibers cellulose. 11. Method according to claim 1, 2 or 3, characterized in that we add, in addition to a and b or in addition of a and b and of the bonding agent, at least one product chosen from the group consisting of polyacrylamides, polyethyleneimines, carboxymethylcellulose, resins urea-formaldehyde, melamine-formaldehyde resins, resins aminopolyamide-epichorhydrin and polyamide resins-epichlorohydrin.