CS244690B2 - Plates from lignocellulose materials and method of theier production - Google Patents

Description

The invention relates to sheets of lignocellulosic materials bonded with cured formaldehyde-based adhesives. The plates according to the invention comprise as a binder a formaldehyde-based adhesive cured in the presence of the formaldehyde-binding agent described below. The invention also relates to a process for the manufacture of these plates.

Boards such as particle boards, particle boards and the like are made of lignocellulosic materials using adhesives. Preferred adhesives or glues for this purpose are based on formaldehyde, for example urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and resorcinol-formaldehyde resins or mixtures thereof. It is a well known fact that boards made using these adhesives have a formaldehyde odor that is both harmful and unpleasant. Formaldehyde is released both in the manufacture of such plates and in their storage or final application.

Numerous methods have been proposed to avoid formaldehyde emissions, but all are either ineffective, or deteriorate in sheet performance, or require complicated application procedures.

Some of these processes include spraying or coating the warm plates coming from the press with various solutions, such as urea and / or ammonia or ammonium salt solutions. These types of methods are generally unsuitable for industrial applications because they require additional work steps and are not very effective anyway.

Other methods involve the use of very complicated mixtures of a large number of ingredients, some of which are natural glues. These products are not very effective either. One drawback is that the properties of natural products are not constant.

Another method of reducing the free formaldehyde content is to use an aqueous suspension of urea lumps coated with a special wax. This method also requires a separate metering line, since the product is not added to the adhesive formulation itself.

It is an object of the present invention to provide plates in which an additive effectively suppresses the formaldehyde odor without compromising the properties of the plates, without altering the reactivity of the adhesive formulations and without requiring additional production steps in the manufacture of particulate boards, plywoods or vines. .

SUMMARY OF THE INVENTION The present invention provides sheets of lignocellulosic materials bonded with cured formaldehyde-based adhesives which comprise as a binder a formaldehyde-based adhesive cured in the presence of an aqueous formaldehyde-binding agent.

(a) at least one organic hydroxy compound selected from divalent, trivalent and pentavalent alcohols containing up to 6 carbon atoms, monosaccharides containing up to 6 carbon atoms, disaccharides containing up to 12 carbon atoms and polysaccharides having an Ostwald viscosity of up to 200 mPa.s at 25 ° C and a concentration corresponding to a refraction of 37%, monovalent and polyvalent aromatic alcohols containing one benzene ring and monovalent and polyvalent phenols,

b) at least one amide selected from the group consisting of aliphatic amides containing up to 6 carbon atoms and aromatic amides with one benzene ring, and optionally

c) an aliphatic monovalent alcohol having 1 to 4 carbon atoms and / or optionally

d) a water-soluble salt of hydrohalic acid, wherein the weight ratio of component a) plus component c) plus component d), if components c) and d) are present, to component b) is in the range from 10: 100 to 400: 100.

The present invention further provides a process for the manufacture of these sheets by compression, wherein the formaldehyde-based adhesive used as a binder is cured. This method is characterized in that the curing of the adhesive takes place in the presence of the admixed formaldehyde-binding agent described above.

An aliphatic monovalent alcohol having 1 to 4 carbon atoms (component c)) acts as a solvent for components a) and b) and also reacts with formaldehyde. Even if the individual components are not water-soluble, they can dissolve in it when the mixture is heated to 70 ° C in water.

The organic hydroxy compounds (component a)) are preferably soluble in water or lower monovalent aliphatic alcohols.

Specific examples of suitable organic hydroxy compounds include monoethylene glycol, diethylene glycol, glycerin, pentaerythrite, fructose, mannose, sorbitol, dextrose, sucrose, maltose, lactose, dextrin, phenol, resorcinol, hydroquinone and the like.

The amides used in the formaldehyde binder (component b)) are preferably soluble in water or lower monovalent aliphatic alcohols.

Suitable examples of amides include urea, thiourea, formamide, acetamide, benzamide, oxamide, succinamide, malonamide and the like.

The formaldehyde-binding agent may optionally contain additives which are monovalent aliphatic alcohols containing 1 to 4 carbon atoms, such as methanol, ethanol, isopropyl alcohol and the like (component c)) to increase solubility.

A cheaper and more efficient formaldehyde-binding agent is added by adding component d) which is a salt of a hydrohalic acid, preferably an alkali metal or alkaline earth metal halide such as sodium chloride, potassium chloride and calcium chloride.

The weight ratio of the amount of the organic hydroxy compound (component a) plus the optional component c) / plus the amount of any inorganic compound present (component d) / to the amount of the amide (component b)) is in the range from 10: 100 to 400: 100. : 100 to 200: 100.

The formaldehyde binding agent may be added to conventional adhesive formulations in an amount ranging from 1 to 10%, preferably from 3 to 7%, said percentages being calculated on the solids content of the formaldehyde binding agent and based on the weight of the liquid resin containing 65% by weight of solid resin.

The formaldehyde-binding agent may comprise. 20 to 80% by weight, preferably 50 to 70% by weight of the active ingredients, ie component a) plus component b) and optionally component c) and / or component d). The water content of the formaldehyde binding agent depends on the solubility of the active ingredients and on the amount of water that can be tolerated in the adhesive formulations.

The formaldehyde-binding agent can simply be prepared by introducing the active ingredients and water into a mixer and mixing the mixture until the active ingredients are dissolved. Mixing is ^already e m ^{ade p} rov t ^{BC s} and the temperature as it indoors ^and not ^{b when} the increased ^{width of} the Ene ^T emperature, ^d 70 ° C.

The formaldehyde-binding agent can be used wherever boards of lignocellulosic materials are produced using formaldehyde-based adhesives such as urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde or resorcinol-formaldehyde resins or mixtures thereof.

Using a formaldehyde-binder, boards that actually contain less than 10 mg of free formaldehyde per 100 g of dry board can be produced as measured by F.E.

S. Y. P. (European Federation of Syndicats des Fabricants de Panneaux de Particules) by perforator method No EN 120.

The extent of free formaldehyde reduction depends on many factors and can therefore vary within wide limits. If the free formaldehyde emission is high (greater than 50 mg formaldehyde per 100 g dry plate), it can be as low as 60 or 85%. If the emission of free formaldehyde is relatively low, ie 20 to 50 mg of free formaldehyde per 100 g of dry plate, the maximum reduction is usually about 50 to 60%. The extent of the reduction achieved also depends on the formaldehyde binder used: the more formaldehyde binder used, the lower the amount of free formaldehyde.

Surprisingly, when the active ingredients of the formaldehyde binder are used in combination, the reduction in the free formaldehyde content is much higher than the sum of the effects of the individual components, and the combination does not favorably affect the reactivity of the adhesive formulation and the properties of the boards.

The following examples serve to illustrate the invention in greater detail. The examples are illustrative only and do not limit the scope of the invention in any way. All parts and percentages given in the examples are parts and percentages by weight.

He did

In this example, the hydroxyl group-containing organic compound is glycerin and the amide is urea. In the example, the synergistic behavior of the two compounds is illustrated. Various adhesive formulations are made and then used to produce particle boards.

The control sample does not contain any of the components of the formaldehyde binding agent. Sample I contains both glycerin and urea, sample 2 contains only glycerin and sample 3 contains only urea.

It can be seen from the tables below that glycerin used alone (Sample 2) is a very effective formaldehyde-binding agent, whereas urea (Sample 3) provides a lower level of formaldehyde reduction and, in addition, the plates have inferior mechanical properties and worse water resistance. However, when urea is used in combination with glycerin (sample 1), the same values are obtained as with glycerin alone.

Thus, a cheaper and less effective product (urea) can be used, which product is forced to react as efficiently as the more expensive and more efficient product (glycerin). Efficacy refers to the ability to absorb formaldehyde as well as to maintain good mechanical properties and good water resistance, which are achieved without changing the reactivity of the adhesive formulation and without the need to introduce any special equipment.

In particular, the reduction in formaldehyde content achieved is 46% in this case.

The compositions used have the following composition;

Means 1 2 3

number 1 part weight 2 parts by weight 3 parts Glycerin (100%) 270 590 - urea (100%) 320 - 590 water 410 410 410 1 000 1 000 1 000 Solids content (%) 59 59 i 59

The following adhesive formulations were used:

Substance and Quantity (g) Control

Sample number of urea-formaldehyde resin 65% with a molar ratio of formaldehyde to urea

1.27: 1 30 077 3 077 3 077 3 077 hardener (chloride) ammonium) 15% 400 400 400 400 paraffin emulsion 50% 250 250 250 250 ammonia 25 ° Baumé 5 5 5 5

Continuation

Substance and its amount

Sample number

Italy (9) Checklist 1 2 3 Device No. 1 - 308 - - Device No. 2 - - 308 - Device 3 - - - 308 water 268 - - - total 4 000 4 040 4 040 4 040 gelation time (s) 68 68 71 62 Each of the above formulations is sprayed on 25 kg of wood chips and from these Chips made on a laboratory the device produces single-layer boards. The plates are pressed at 10, 9 and 8 s / mm. The plate thickness is 17.3 mm. The press temperature is ²⁰⁰ ° C and the pressing pressure is 3.5 MPa. Dimensions of produced boards are 40 x 56 cm. The results are shown in the following table. These are average values. Sample number Checklist 1 2 3 density (kg / m3) 683 669 663 657 bending strength (MPa) 19.9 18.1 17.3 16.3 tensile strength (MPa) 0.73 0.72 0.71 0.63 increase in thickness by swelling after 2 hours 5.2 4.9 4,5 ' 5.4 increase in thickness by swelling after 24 hours (%); 51.4 49.9 47.4 53.1 free formaldehyde (mg / 100 g dry plate) 15.8 8.5 8.7 11.7

r

la

This example also illustrates the synergistic behavior of a mixture of glycerin and urea in reducing the free formaldehyde content of the particle board while maintaining the mechanical properties of the plates and their water resistance.

The control sample contains no formaldehyde binding agent component. Sample 1 and Sample 2 contain only one more effective one.

it contains the two components of the formaldehyde-binding agent of them, the one of these two components providing a free formaldehyde content below 10 mg / 100 g dry plate (which is the desired level for the E1 class) and only this sample provides a plate with exactly the same mechanical properties and water resistance. The reduction of the free formaldehyde content in this particular case is 34%.

From the tabulated values it is apparent that only the sample

The samples used have the following composition:

Sample 1

Sample No. 2 Glycerin (100%) (parts by weight) Urea (dw) (100%)

128

128

424 water

Sample 1

448

000

Sample 2

872

000 solids content (%)

55.2

12.8

The adhesive formulation used has the following composition:

Substance Sample content (g) Control Sample No. 1 Sample 2

urea-formaldehyde resin (mole ratio) formaldehyde to urea blame 1,27: 1) 3 077 3 077 3 077 hardener (chloride) ammonium 15%) 400 400 400 paraffin emulsion (50%) 250 250 250 amon ⁱ ak ²⁵ ° Baum ^é 5 5 5 Device No. 1 - 268 - Device No. 2 - - 268 water 268 - - total 4 000 4 000 4 000 gelation time (s) 66 67 69

Each of the above formulations is sprayed onto 25 kg of wood chips, and the chips are made on a laboratory apparatus (monolayer). The plates are pressed ^{at 10,} 9 and ⁸ s / mm. ^ A thickness plates 1 ⁷ 3 mm. Te ^pl of the ^Hsu-200 DEG C. Mixing and ^{if d t} l and ^k is 3.5 MPa. Dimensions of produced boards are 40 x 56 cm.

The results are shown in the following table. These are average values.

Sample number Checklist 1. . 2 density (кд / щЗ) 685 684 687 bending strength (MPa) 20.7 20.6 '19.4 tensile strength (MPa) 0.74 0.73 0.67 increase in thickness by swelling after 2 hours (%) 11.0 7.9 8.6 increase in thickness by swelling after 24 hours (%) 23.4 23.2 23.7 free formaldehyde content (mg / 100 g dry plate) 14.3 9.5 12.3

Example 3

This example illustrates the effectiveness of a combination of monoethylene glycol and urea as a formaldehyde binding agent.

Two formulations were prepared, one control containing no component of the formaldehyde binder and the other containing both monoethylene glycol and urea (sample 1).

Using these two adhesive formulations a chipboard is produced, and it is shown that using a formaldehyde-binding agent in formaldehyde resin yields sheets that fall into the class of normal sheets falling into class E 2 (control sample).

boards. Even in this connection with ureaE 1 (sample 1), while

The reduction in the free formaldehyde content in this particular case is 37%.

The composition used in Sample 1 has the following composition:

monoethylene glycol 100% (parts by weight) 360 urea 100% (parts by weight) 365 water (parts by weight) 275 solids content (%)

000

72.5

The adhesive formulations used have the following composition:

Substance

Sample content (g) Control sample

Sample No. 1 urea-formaldehyde resin 65% (molar ratio

formaldehyde to urea 1.27: 1) 3 077 3 077 hardener (ammonium chloride 15%) 400 400 paraffin emulsion 50% 250 250 amon ⁱ and ^{k 25} ° Baumé 5 5 a formaldehyde-binding agent - 268 water 268 - total 4 000 4 000 gelation time (s) 66 60

Each of the above formulations is sprayed onto 25 kg of wood chips and made from these chips on a laboratory apparatus with single layer boards. The plates are pressed at

1 ^0, 9 and β s / mm. The thickness of the dese ^k is ^17.3 mra. Lota Te ^p l ⁱ are ²⁰⁰ ° C ^and al stamper ^{thickness d where}

3.5 MPa. Dimensions of produced boards are 40 x 56 cm.

The results are shown in the following table. These are average values.

Sample number

Control density (kg / m ³ ) 685 flexural strength (MPa) 20.7 tensile strength (MPa) 0.74 increase in thickness by swelling after hours (%) 11.0 increase in thickness by swelling after hours (%) 23.5 content free formaldehyde (rng / 100 g dry plate) 14.3

684

20.2

0.74

8.6

22.6

9.0

Example 4

This example illustrates the synergistic behavior of a combination of monoethylene glycol and urea.

Plates were made using three different formulations. The control sample contains no component of the formaldehyde binding agent of the invention, Sample No. 1 contains both components of the formaldehyde binding agent of the invention, and Sample No. 2 contains only one component.

From the results obtained below, it is clear that sample 1 containing both ingredients is much more effective than sample 2 containing only one ingredient (the one of both ingredients that is more effective).

The reduction in the free formaldehyde content achieved in this particular case is 32%.

The samples used have the following composition:

Substance The content of the substance in composition no. 1 2 monoethylene glycol 100% (parts by weight) 230 580 Urea 100% (parts by weight) 350 - clay water mass) 420 420 1 000 1 000 solids content (%) 58 58

Adhesive formulations have the following composition:

Substance content of the sample (g)

Control 1 2 urea - formaldehyde resin 65% (molar

ratio of formaldehyde to mo- 1.27: 1) 3 077 3 077 3 077 hardener (chloride) ammonium 15%) 400 400 400 paraffin emulsion 50% 250 250 250 ammonium ^{to 25} ° Baumé 5 5 5 Device No. 1 - 268 - Device No. 2 - - 268 water 268 '- - total 4 000 4 000 4 000 gelation time (s) 70 71 76

Each of the above formulations is sprayed onto 25 kg of wood chips and made from these chips in the laboratory to form single-layer boards. The plates are pressed at 10, 9 and 8 s / mn. ^The plate thickness is ^17.3 mm. Temperature ^l IS is ²⁰⁰ ° C and isovac ^{l s} t ^l and ^k is ^3, 5 MPa. R ^y dimension ^of the plates produced are 40 x 56 cm.

The results are shown in the following table. These are average values. Sample number Checklist 1 2 density (kg / m ³ ) 688 688 687 bending strength (MPa) 17.6 17.5 17.5 tensile strength (MPa) 0.55 0.60 0.56 increase in thickness by swelling after 2 hours (%) 6.7 4.9 4.7 increase the thickness after 24 hours absorption 20.1 20.1 19.5 free formaldehyde content (mg / 100 g dry plate) 15.0 10.3 12.3 Example 5 This example illustrates the use resins with a different molar ratio and use different concentrations of the formaldehyde binder. Formaldehyde binding agent used has the following composition: Substance Parts by weight glycerin 100% 270 urea 100% 318 water 412 1 000 content, solids (%) 58.8 Adhesive formulations used for manufacturing individual samples have the following composition: Substance Content of the substance in the sample (G) Checklist 1 2 3

urea-formaldehyde resin 65% (formaldehyde / urea molar ratio of 1.4: 1) hardener (ammonium chloride 15%) paraffin ammonium ^{i 25} composition aldehyde water emulsion 50% ° Baumé formula binding gelation time (s)

3 077 3 077 3 077 3 077 293 380 380 380 250 * 250 250 250 5 5 5 5 - 154 215 375 375 134 73 - 4 000 4 000 4 000 4 087 73 73 72 75

The boards are pressed at 10 ° c and the pressing ^pressure and ^k is 3.5 MPa.

Each of the above formulations is sprayed onto 25 kg of chips and monolayer plates are made on a laboratory apparatus. 9 and 8 s / mm. The plate thickness is 17.3 mm. The temperature of the press is ²⁰⁰ ° <The dimensions of the produced boards are 40 x 56 cm.

The results are shown in the following table. These are average values.

Sample number Checklist 1 2 3 ^h usta.a (kg / m ² ) 680 687 685 688 bending strength (MPa) 22.0 22.5 22.3 21.6 tensile strength (MPa) 0.61 0.63 0.66 0.64 increase in thickness by swelling after 2 hours (%) 10.1 9.3 8.8 9.5 increase in thickness by swelling after 24 hours (%) 20.6 21.8 21.0 21.5 free formaldehyde content (mg / 100 g dry plate) 22.2 13.0 10.1 9.5

The tabulated results show that the mechanical properties of the produced boards are the same and their water resistance is the same, but the reduction in free formaldehyde content is 41% for Sample 1, 55% for Sample 2 and 3 for Sample 3. 57%.

Example 6

This example illustrates the use of six different types of polyalcohols, two different types of amides, and one optional additive. The weight ratio of alcohol to amide varies from 57.5: 100 to 385: 100.

The composition of the different types of formaldehyde binding agents is shown in the following table:

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sample δ. 3 - - - 307

The above results show that all test samples showed the same mechanical properties and water resistance values as the control, with a reduction in formaldehyde content ranging from 32 to 47%.

Example 7

Three different types of hydroxyl-containing organic compounds, dextrin, phenol and resorcinol, are used in this example.

Also illustrated is the use of one monovalent alcohol other than methanol as an optional additive, namely ethanol.

The phoniphaldehyde binding agents used have the following composition:

Sample number 1 2 3 4 monoethylene glycol 230 - - - dextrin - 140 - - phenol - · - ' 130 - resorcinol - - - - methanol - 140 130 130 ethanol 80 - - - urea 350 350 370 370 water 340 370 370 370 1 000 . 1 000 1 000 1 000 solids content 66 63 63 63

All the above values are given in parts by weight. The samples of formaldehyde binding agents are used in this example to replace a portion of the resin.

Adhesive formulations of the following composition are used:

Substance Content of substance in sample No (g) Checklist 1 2 '3 4 urea-formaldehyde Resins (solar measure aldehyde / urea to 1.27: 1) 3 077 2 770 2 770 2 770 2 770 hardener (15% solution) ammonium chloride) 400 500 400 450 400 paraffin emulsion 50% 1 250 250 250 250 250 amon ^even if ^two 5-aum 5 - - - - binding agent formaldehyde sample 1 - 307 - - - sample No. 2 - - 307 - - sample No. 3 - - - 307 - sample No. 4 - - - - 307 water 268 - - - - total 4 000 3 827 3 727 3 777 3 727 gelation time (s) 65 64 62 63 63

Each of the above formulations is sprayed onto 25 kg of wood chips and made from these chips in the laboratory to form single-layer boards. The plates are pressed at 10, 9 and 8 s / mm. Tl ^STARTUP ka plates ^{1 7} 3 mm. Te ^p lota ^When SU ²⁰⁰ ° C and Hsova ^.mu.l З and ^k is ⁵ MPa. R ^y dimension ^of the plates produced are 40 x 56 cm.

The results are shown in the following table. Acts the average values. Sample number Property Checklist 1 2 3 4 density (kg / m) 702 698 695 705 710 bending strength (MPa) 20.1 19.5 19.7 20.0 20.8 tensile strength (MPa) 0.75 0.70 0.75 0.73 0.72 width increase after swelling for 2 hours (%) 7.1 6.8 6.5 6.3 6.6 width increase after swelling for 24 hours (%) 20.3 21.5 21.3 21.8 21.3 free formaldehyde content (img / 100 g dry plate) 13.1 9.6 9.2 8.2 10 reduction of free formal content dehydu (%) - 27 Mar: 30 37 24

The above results show that all samples have mechanical properties and water resistance values consistent with a control sample containing no formaldehyde-binding agent, although this composition replaces the equivalent amount of urea-formaldehyde resin in the adhesive formulation in the test samples. The reduction in the free formaldehyde content in this example ranges from 24 to 37%.

Example 8

In this example, one type of formaldehyde-binding agent is used and phenol-melamine-urea-formaldehyde resin is used as the resin.

The formaldehyde-binding agent used has the following composition:

Substance Parts Monoethylene Glycol Urea Water

300

330

370

000

The adhesive formulation used has the following composition:

Substance

Sample content (g)

Control 1 phenol-melamine-urea-formaldehyde resin

53 (53% 5 600 5 600 hardener (15.5% solution ammonium chloride) 840 840 paraffin emulsion 50% 150 150 binding agent formaldehyde - 560 6 590 7 150 gelation time (s) 73 79

Each of the above formulations is sprayed onto and from 25 kg of wood chips. The plates are pressed at 10, 9 and 8 s / mm.

Te ^pl of ^T, and ^if SU ²⁰⁰ ° C and ^{if the} stamper and ^{the thickness d} is ^3.5 MPa. R ^y dimension ^of 56 cm.

chips in the laboratory prepared boards monolayer Thickness Esek ^bt k ^d is ^17.3 mm.

produced boards are 40 x

The results are shown in the following table. These are average values.

Properties density (kg / m) flexural strength (MPa) tensile strength (MPa) tensile strength V 100 (MPa) increase in thickness by swelling after 2 hours (%) increase in thickness by swelling after 24 hours (%) free formaldehyde content (mg / 100 g boards dry) Free formaldehyde reduction (%)

Sample number

Checklist

705

26.2

0.27

2.7

7.1

12.0

12.8

695

25.9

0.26

2.6

6.2

11.3

The above results show that the formaldehyde-binder can also be used with phenol-melamine-urea-formaldehyde resins and, in this case, significantly reduces the free formaldehyde emission without adversely affecting the properties of the sheets produced. ·

Example 9

In this example, the formaldehyde binding agent comprises an inorganic component (component (d)), which in this case is illustrated by sodium chloride.

The binding agent used. formaldehyde has the following composition:

Substance

Parts by weight monoethylene glycol 100% urea 100% sodium chloride 100% water total solids content (%)

270

318

362

000

63.8

The adhesive formulations used in each sample have the following composition:

Substance Sample content (g) Checklist 1 urea-formaldehyde resin (molar ratio forrnaldehyde / urea 1.27: 1) 3 077 2 770 hardener (15% solution) ammonium chloride) 400 450 paraffin emulsion 50% 250 250 ammonium ^to 25 ° Baumé 5 - a formaldehyde-binding agent - 307 water 268 - total 4 000 3 777 gelation time (s) 65 64

Each of the above formulations is sprayed onto 25 kg of wood chips and made from these chips in the laboratory to form single-layer boards. The plates are pressed at 10, 9 and 8 s / mm. ^STL thickness and terror ^to 17.3 mm. Melting ^l IS Ж ° C is compressed and pressure is ^3, 5 MPa. Ro me ^{of hole} plates are made of 40 x 56 cm.

The results are shown in the following table. These are average values.

Property Sample number Checklist 1 density (kg / m ³ ) 695 699 bending strength (MPa) 19.9 19.5 tensile strength (MPa) 0.71 0.73 increase in thickness by swelling after 2 hours (%) 7.0 6.6 increase in thickness by swelling after 24 hours (%) 20.5 20.8 free formaldehyde content (mg / 100 g dry plate) 17 9.5 reduction of formaldehyde content - 44

The results show that the sample containing the formaldehyde-binding agent has the same values as the control sample, although a portion of the urea-formaldehyde resin in the adhesive formulation has been replaced by the formaldehyde-binding agent. The free formaldehyde reduction is 44%.

OBJECT OF THE INVENTION

Claims (14)

Plates of lignocellulosic materials bonded with cured formaldehyde-based adhesives, characterized in that they comprise as a binder a formaldehyde-based adhesive cured in the presence of an aqueous formaldehyde-binding agent. a) at least one organic hydroxy compound selected from divalent, trivalent and pentavalent alcohols containing up to 6 carbon atoms, monosaccharides containing up to 6 carbon atoms, disaccharides containing up to 12 carbon atoms and poly sa.charidy s ^o s ^{t d} wal verifies viscosity ^{of d p} of 200 m and ^p s 25 ° C and a concentration equal ^to or Refr 37%, monovalent and polyvalent aromatic alcohols containing one benzene nucleus and monovalent and polyvalent phenols; (b) up to at least one amide selected from the group consisting of aliphatic amides containing 6 to 6 carbon atoms and aromatic amides containing one benzene ring; and optionally) an aliphatic monovalent alcohol containing 1 to 4 carbon atoms and / or optionally d) a water-soluble salt of hydrohalic acid, wherein the weight ratio of a) plus component c) plus component d), if components c) and d) are present, to component b) in the range from 10: 100 to 400: 100. folder is' 2. Plates according to claim 1, characterized in that the formaldehyde-binding agent consists of a solution of components a), b) and optionally c) in water. is an alkali metal or alkaline earth metal halide, preferably sodium chloride, potassium chloride or calcium chloride. 3. Plates according to claim 1, characterized in that component d) is water-soluble 4. A water-permeable plate according to any one of claims 1 to 3, wherein component (a) is a monovalent aliphatic alcohol containing from 1 to 4 carbon atoms. 5. A water-permeable board according to any one of Claims 1 to 4 wherein component (b) is a monovalent aliphatic alcohol containing from 1 to 4 carbon atoms. 6. A plate according to claim 20, comprising from 20 to 80% by weight of any one of items 1 to 5, characterized in that the additives. The composition content of the composition wherein said up to 6, wherein the formaldehyde binding agent is 1 to 10 4, preferably 3 to 7 8% by weight, the percentages are based on the solids content of the formaldehyde binding agent and are based on the weight of the liquid resin containing 65% by weight of solid resin. 7. Boards according to any one of items 1 8. A process for producing boards of lignocellulosic materials according to any one of items 1 to 4 7. A curing process comprising the step of curing a formaldehyde-based adhesive used in a formaldehyde-based solution-containing adhesive composition comprising at least one organic hydroxy compound selected from the group consisting of divalent, trivalent and pentavalent alcohols. containing up to 6 carbon atoms, monosaccharides to 6 carbon atoms, disaccharides containing up to 12 carbon atoms and polysaccharides having an Ostwald in skoz ^{and also} to the ^two 00 mPa.s ^at 25 ° C and concentration of ^{dp i} s ^{s s} refraction ^and mar gin ^{3 7%, d} is nomocn ^s and polyhydric aromatic alcohols containing one benzene ring and monohydric and polyhydric phenols. and) b) up to 6 of at least one amide selected from the group consisting of carbon atoms and aromatic amides comprising one of aliphatic amides containing one benzene ring, and optionally c) an aliphatic monovalent alcohol having 1 to 4 carbon atoms and / or optionally (d) a water-soluble salt of hydrohalic acid in water, wherein the weight ratio of component (a) plus component (c) plus component (d), if present, components (c) and (d) to component (b) is in the range of 10: 100 to 400: 100 ALIGN! 9. The method of claim 8, wherein the formaldehyde-binding agent is a solution of components a), b) and optionally c) in water. Process according to claim 8, characterized in that component d) is a water-soluble alkali metal or alkaline earth metal halide, preferably sodium chloride, potassium chloride or calcium chloride. 11. A process according to any one of Claims 8 to 10 wherein component (a) is soluble in water or a monovalent aliphatic alcohol containing from 1 to 4 carbon atoms. 12. A process according to any one of Claims 8 to 11 wherein component (b) is soluble in water or a monovalent aliphatic alcohol containing from 1 to 4 carbon atoms. 13. A process according to any one of Claims 8 to 12 wherein the composition comprises 20 to 80% by weight of the active ingredients. 14. A method according to any one of claims 8 to 13, wherein the content of the formaldehyde-binder is 1 to 10%, preferably 3 to 7% by weight, said percentages being calculated on the solids content of the formaldehyde-binder and based on the weight of the liquid resin containing 65% by weight of solid resin.