BINDER COMPOSITION COMPRISING AMINO ACID POLYMER(S) AS WELL AS CARBOHYDRATES FOR COMPOSITE ARTICLES

Abstract

The present invention relates to a binder composition comprising a) Component A comprising amino acid polymer(s) A1 and b) Component B comprising component B1 selected from the group consisting of pentoses, hexoses, disaccharides of pentoses and/or hexoses and mixtures thereof, wherein the amino acid polymer(s) A1 has(have) a total weight average molecular weight Mw, total of at least 800 g/mol and at most 10.000 g/mol and wherein the binder composition comprises at least 55 wt.-% amino acid polymer(s) A1 based on the total weight of the amino acid polymer(s) A1 and component B1.

Claims

1.-13. (canceled)

14. Use of a binder composition comprising a) Component A comprising amino acid polymer(s) A1 and b) Component B comprising component B1 selected from the group consisting of pentoses, hexoses, and disaccharides of pentoses and/or hexoses and mixtures thereof, wherein the amino acid polymer(s) A1 has(have) a total weight average molecular weight M.sub.w,total of at least 800 g/mol and at most 10,000 g/mol and wherein the binder composition comprises at least 55 wt.-% amino acid polymer(s) A1 based on the total weight of the amino acid polymer(s) A1 and component B1, for producing a multi-layer particle board comprising a core layer and at least one surface layer, wherein the surface layer comprises said binder composition, and the core layer comprises a binder selected from the group consisting of urea/formaldehyde binder, phenol/formaldehyde binder, melamine/urea/formaldehyde binder, PMDI binder and mixtures thereof.

15. Use according to claim 14, wherein the carbohydrates are selected from the group consisting of glucose, fructose, xylose, sucrose and mixtures thereof.

16. Use according to claim 1, wherein the amino acid polymer(s) A1 comprise polylysine(s).

17. Use according to claim 1, wherein the component A comprises as further component A2 and/or component B comprises as further component B2 urea and/or urea derivative(s).

18. Use of a reacted binder composition obtainable or obtained by reacting the binder components as defined in claim 14 for producing a multi-layer particle board comprising a core layer and at least one surface layer, wherein the surface layer comprises said binder composition, and the core layer comprises a binder selected from the group consisting of urea/formaldehyde binder, phenol/formaldehyde binder, melamine/urea/formaldehyde binder, PMDI binder and mixtures thereof.

19. Use of a composition kit comprising the binder composition as defined in claim 14 wherein Component(s) A and B are stored separately for producing a multi-layer particle board comprising a core layer and at least one surface layer, wherein the surface layer comprises said binder composition, and the core layer comprises a binder selected from the group consisting of urea/formaldehyde binder, phenol/formaldehyde binder, melamine/urea/formaldehyde binder, PMDI binder and mixtures thereof.

20. A multi-layer particle board comprising at least one core layer and at least one surface layer, wherein the surface layer comprises a binder composition as defined in claim 14 or a reacted binder composition obtained by reacting the binder components as defined in claim 14 and the core layer comprises a binder selected form the group consisting of urea/formaldehyde binder, phenol/formaldehyde binder, melamine/urea/formaldehyde binder, PMDI binder and mixtures thereof.

21. A multi-layer particle board according to claim 20, wherein the formaldehyde emission measured according to EN717-2 is lower than 2.0 mg/m.sup.2h.

22. A multi-layer particle board according to claim 20 wherein the lignocellulosic pieces are prepared from wood.

23. A process for the batchwise or continuous production of lignocellulosic composite articles which are multi-layered lignocellulose-based boards with a core and with at least one upper and one lower surface layer, comprising the following steps: a) mixing of the lignocellulosic pieces with a binder composition for each layer, wherein in the multi-layer boards at least one upper and one lower surface layer comprises a binder composition as defined in claim 14, and the core layer comprises a binder selected form the group consisting of urea/formaldehyde binder, phenol/formaldehyde binder, melamine/urea/formaldehyde binder, PMDI binder and mixtures thereof, b) layer-by-layer scattering of the mixtures of the individual layers to form a mat, and c) pressing the mat to a board at a temperature of 80 to 300 C. and at a pressure of 1 to 100 bar or c) pressing the mat to a board at a temperature of 80 to 200 C. and at a pressure of 0.1 to 100 bar, wherein a high-frequency electrical field is applied during pressing until 80 to 200 C. is reached in the center of the mat.

24. A process according to claim 23, wherein the board obtained in step c or c) has a formaldehyde emission measured according to EN717-2 lower than 2.0 mg/m.sup.2h.

25. The process according to claim 23, wherein both components A and B of the binder composition or both components A and B of a composition kit comprising the binder composition as wherein Component(s) A and B are stored separately, are added to the lignocellulosic pieces in step a) either a1) separately from one another or a2) as a mixture.

26. The process according to claim 23 wherein the lignocellulosic pieces are prepared from wood.

Description

EXAMPLES

Example 1a

Synthesis of Polylysine-2

[0417] 2200 g of L-lysine solution (50% in water, ADM) was heated under stirring in an oil bath (external temperature 140 C.). Water was distilled off and the oil bath temperature was increased by 10 C. per hour until a temperature of 180 C. was reached. The reaction mixture was stirred for an additional hour at 180 C. (oil bath temperature) and then pressure was slowly reduced to 200 mbar. After reaching the target pressure, distillation was continued for another 120 min. The product (Polylysine-2, M.sub.w 2010 g/mol) was hotly poured out of the reaction vessel, crushed after cooling and dissolved in water to give a 50 wt.-% solution.

Example 1b

[0418] Synthesis of Polylysine-3

[0419] 2200 g of L-lysine solution (50% in water, ADM) was heated under stirring in an oil bath (external temperature 140 C.). Water was distilled off and the oil bath temperature was increased by 10 C. per hour until a temperature of 180 C. was reached. The reaction mixture was stirred for an additional hour at 180 C. (oil bath temperature) and then pressure was slowly reduced to 200 mbar. After reaching the target pressure, distillation was continued for another 210 min. The product (Polylysine-3, M.sub.w 3360 g/mol) was hotly poured out of the reaction vessel, crushed after cooling and dissolved in water to give a 50 wt.-% solution.

Example 1c

[0420] Carbohydrate Solution CS

[0421] 165 g of glucose monohydrate and 150 g of fructose are mixed with 285 g of water and stirred to a solution.

Example 2

[0422] Three-Layered 16 mm Chipboards

Preparation of Resinated Core Layer Chips (Example 2-1 to 2-7)

[0423] In a mixer, a mixture of 748 g of Kaurit glue 350 (urea formaldehyde resin, 65% solid content) and 22.4 g of ammonium sulfate was sprayed onto 5.58 kg (5.40 kg dry weight) of spruce core layer chips (moisture content 3.4%) while mixing. Subsequently, 95 g of water was sprayed onto the mixture to adjust the final moisture of the resinated chips while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips Comparative (Example 2-1)

[0424] 42.1 g of HMDA, 155 g of glucose monohydrate and 141 g of fructose were mixed with in 310 g of water und stirred until all components were fully dissolved. After 5 min this solution was sprayed in a mixer onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 2-2)

[0425] In a mixer, 84.2 g of Polylysine-2 solution (50 wt.-% in water) was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Subsequently, 564 g of carbohydrate solution CS was sprayed onto the mixture while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 2-3)

[0426] In a mixer, 486 g of Polylysine-2 solution (50 wt.-% in water) was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Subsequently, 162 g carbohydrate solution CS was sprayed onto the mixture while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 2-4)

[0427] In a mixer, 389 g of Polylysine-2 solution (50 wt.-% in water) was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Subsequently, 259 g of carbohydrate solution CS was sprayed onto the mixture while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 2-5)

[0428] In a mixer, a mixture of 748 g of Kaurit glue 350 (65% solid content) and 22.4 g of ammonium sulfate, was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Subsequently, 62.0 g of water was sprayed onto the mixture to adjust the final moisture of the resinated chips while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 2-6)

[0429] In a mixer, 486 g of Polylysine-3 solution (50 wt.-% in water) was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Subsequently, 162 g of carbohydrate solution CS was sprayed onto the mixture while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 2-7)

[0430] In a mixer, 486 g of Polylysine-2 solution (50 wt.-% in water) was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Subsequently, 162 g of a xylose solution (50 wt.-% in water) was sprayed onto the mixture while mixing. Thereafter, mixing was continued for 3 min.

Pressing the Resinated Chips to Chipboards (Example 2-1 to Example 2-7)

[0431] Immediately after resignation, 452 g of resinated surface layer chips, followed by 1807 g of resinated core layer chips, followed by 452 g of resinated surface layer chips, were scattered into a 56.544 cm mold and pre-pressed under ambient conditions (0.4 N/cm.sup.2). Subsequently, the pre-pressed chip mat thus obtained was removed from the mold, transferred into a hot press and pressed to a thickness of 16 mm to give a chipboard (temperature of the press plates 210 C., max pressure 4 N/mm.sup.2, presstime 96 s, 128 s or 160 s, board thickness was adjusted by two steel spacing strips which were inserted in the press).

TABLE-US-00002 TABLE 1 3-layered chipboards, 16 mm, binder in core layer: Kaurit glue 350 9 wt.-% (solid/dry wood), surface layers as given, binder amount in surface layers 6 wt.-% (solid/dry wood) press internal binder in surface layers time bond formaldehyde amine carbohydrate carbohydrate additional factor density strength emission example component component 1 component 2 component [s/mm] [kg/m.sup.3] [N/mm.sup.2] [mg/m.sup.2h] 2-1* 13% 43.5% 43.5% 6 655 0.34 4.2 HMDA Glucose Fructose 8 658 0.34 4.4 10 660 0.34 4.1 2-2* 13% 43.5% 43.5% 6 652 0.42 4.3 Polylysine-2 Glucose Fructose 8 656 0.43 4.3 10 659 0.45 3.7 2-3 75% 12.5% 12.5% 6 666 0.88 1.5 Polylysine-2 Glucose Fructose 8 668 0.84 1.6 10 663 0.78 1.3 2-4 60% 20% 20% 6 649 0.72 1.7 Polylysine-2 Glucose Fructose 8 660 0.74 1.6 10 658 0.74 1.6 2-5 Kaurit 8 690 0.87 2.7 350 ** 2-6 75% 12.5% 12.5% 8 672 0.85 1.5 Polylysine-3 Glucose Fructose 2-7 75% 25% 8 687 0.82 1.6 Polylysine-2 Xylose *Comparative Example ** binder amount 9 wt.-% (solid/dry wood), 3 wt.-% (solid/binder solid) ammonium sulfate as hardener

[0432] Surprisingly, boards according to the present invention having an excess of polylysine in the surface layer provide an excellent internal bond strength as well a very low formaldehyde emission.

Example 3

[0433] 10 mm Single-Layer Chipboards by Pressing in a High-Frequency Press

Preparation of the Resinated Chips for Comparative Example 3-1 (Glue Amount 6 wt.-%)

[0434] In a mixer, 32.0 g of water was sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. Subsequently, a mixture of 73.8 g of Kaurit glue 340 (65% solid content), 1.44 g of ammonium sulfate and 22.1 g of water was sprayed to this mixture within 1 min while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Comparative Example 3-1 (Glue Amount 10 wt.-%)

[0435] In a mixer, a mixture of 123 g of Kaurit glue 340 (65% solid content), 2.40 g of ammonium sulfate and 36.8 g of water sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Comparative Example 3-2 (Glue Amount 6 wt.-%)

[0436] In a mixer, 32.0 g of water was sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. Subsequently, a mixture of 37.0 g of L-lysine, 12.0 g of glucose monohydrate, and 47.0 g of water was sprayed to this mixture within 1 min while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Comparative Example 3-2 (Glue Amount 10 wt.-%)

[0437] In a mixer, a mixture of 61.6 g of L-lysine, 20.0 g of glucose monohydrate and 78.4 g of water sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Example 3-3 (Binder Amount 6 wt.-%)

[0438] In a mixer, 32.0 g of water was sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. Subsequently, a mixture of 74.0 g of Polylysine-2 solution (50 wt.-% in water), 12.0 g of glucose monohydrate, and 10.0 g of water was sprayed to this mixture within 1 min while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Example 3-3 (Binder Amount 10 wt.-%)

[0439] In a mixer, a mixture of 123 g of Polylysine-2 solution (50 wt.-% in water), 20.0 g of glucose monohydrate and 16.9 g of water sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Example 3-4 (Binder Amount 6 wt.-%)

[0440] In a mixer, 32.0 g of water was sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. Subsequently, a mixture of 74.0 g of Polylysine-3 solution (50 wt.-% in water), 12.0 g of glucose monohydrate, and 10.0 g of water was sprayed to this mixture within 1 min while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Example 3-4 (Binder Amount 10 wt.-%)

[0441] In a mixer, a mixture of 123 g of Polylysine-3 solution (50 wt.-% in water), 20.0 g of glucose monohydrate and 16.9 g of water sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Example 3-5 (Binder Amount 6 wt.-%)

[0442] In a mixer, 32.0 g of water was sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. Subsequently, a mixture of 74.0 g of Polylysine-2 solution (50 wt.-% in water), 11.0 g of fructose, and 11.0 g of water was sprayed to this mixture within 1 min while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Example 3-5 (Binder Amount 10 wt.-%)

[0443] In a mixer, a mixture of 123 g of Polylysine-2 solution (50 wt.-% in water), 18.4 g of fructose and 18.5 g of water sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Example 3-6 (Binder Amount 10 wt.-%)

[0444] In a mixer, a mixture of 88.0 g of Polylysine-2 solution (50 wt.-% in water), 19.6 g of glucose monohydrate, 18.0 g of fructose and 34.4 g of water sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Example 3-7 (Binder Amount 10 wt.-%)

[0445] In a mixer, a mixture of 96.0 g of Polylysine-2 solution (50 wt.-% in water), 17.4 g of glucose monohydrate, 16.0 g of fructose and 30.6 g of water sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

Preparation of the Resinated Chips for Example 3-8 (Binder Amount 10 wt.-%)

[0446] In a mixer, a mixture of 120 g of Polylysine-2 solution (50 wt.-% in water), 10.9 g of glucose monohydrate, 10.0 g of fructose and 19.1 g of water sprayed within 1 min to 816 g (800 g dry weight) of spruce core layer chips (moisture content 2.0%) while mixing. After completion of the spraying, mixing in the mixer was continued for 15 sec.

[0447] Pressing the resinated chips to chipboards in a high-frequency press (Examples 3-1* to 3-8) Immediately after resignation, 610 g of the resinated were scattered into a 3030 cm mold and pre-pressed under ambient conditions (0.4 N/mm.sup.2). Subsequently, the pre-pressed chip mat thus obtained was removed from the mold. For monitoring a temperature sensor (GaAs chip) was introduced into the center of said pre-pressed chip mat. Nonwoven separators were then provided to the upper and lower side of the pre-pressed chip mat. The pre-pressed chip mat was inserted in a HLOP 170 press from Hoefer Presstechnik GmbH, whereby a birch plywood (thickness 6 mm) was placed between the nonwoven separator and the press plate on each side of the mat. The pre-pressed chip mat was then compacted to 10 mm thickness in the press within a period of 2 s, and then heated by applying a high-frequency electrical field (27.12 MHz, anode current 2.5 A) while the press was remaining closed. When the target temperature 130 C. or 150 C. (HF temperature) was reached in the center of the pressed mat, the press was opened.

TABLE-US-00003 TABLE 2 single-layer chipboards, 10 mm, pressed in high-frequency press binder in surface layers internal binder HF bond amine carbohydrate carbohydrate additional amount temperature density strength example component component 1 component 2 component [wt.-%]** [ C.] [kg/m.sup.3] [N/mm.sup.2] 3-1* Kaurit 10 130 662 0.80 340*** 6 130 648 0.52 10 150 659 0.80 3-2* 77% 23% 10 130 no board**** Lysine Glucose 6 130 no board**** 10 150 no board**** 3-3 77% 23% 10 130 652 1.09 Polylysine-2 Glucose 6 130 649 0.76 10 150 658 1.19 3-4 77% 23% 10 130 652 1.07 Polylysine-3 Glucose 6 130 649 0.73 10 150 658 1.15 3-5 77% 23% 10 130 655 1.05 Polylysine-2 Fructose 6 130 651 0.66 10 150 657 1.10 3-6 55% 22.5% 22.5% 10 150 650 1.01 Polylysine-2 Glucose Fructose 3-7 60% 20% 20% 10 150 648 1.20 Polylysine-2 Glucose Fructose 3-8 75% 12.5% 12.5% 10 150 653 1.25 Polylysine-2 Glucose Fructose *Comparative Example **solid/dry wood ***3 wt.-% (solid/binder solid) ammonium sulfate as hardener ****no board means that the resulting material after pressing was not a sound chipboard and showed fractures, blows and/or bursts

Example 4

[0448] Three-Layered 16 mm Chipboards by Pressing in a High-Frequency Press

Preparation of Resinated Core Layer Chips (Example 4-1 to 4-4)

[0449] In a mixer, a mixture of 486 g of Polylysine-2 (50 wt.-% in water), 40.5 g of fructose, 44.2 g of glucose monohydrate and 77.3 g of water was sprayed onto 5.58 kg (5.40 kg dry weight) of spruce core layer chips (moisture content 3.4%) while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 4-1)

[0450] In a mixer, 486 g of Polylysine-2 solution (50 wt.-% in water) was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Subsequently, 162 g carbohydrate solution CS was sprayed onto the mixture while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 4-2)

[0451] In a mixer, 389 g of Polylysine-2 solution (50 wt.-% in water) was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Subsequently, 259 g of carbohydrate solution CS was sprayed onto the mixture while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 4-3)

[0452] In a mixer, 486 g of Polylysine-3 solution (50 wt.-% in water) was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Subsequently, 162 g of carbohydrate solution CS was sprayed onto the mixture while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 4-4)

[0453] In a mixer, 486 g of Polylysine-2 solution (50 wt.-% in water) was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Subsequently, 162 g of a xylose solution (50 wt.-% in water) was sprayed onto the mixture while mixing. Thereafter, mixing was continued for 3 min.

[0454] Pressing the resinated chips to chipboards (example 4-1 to 4-4) Immediately after resignation, 452 g of resinated surface layer chips, followed by 1780 g of resinated core layer chips, followed by 452 g of resinated surface layer chips, were scattered into a 56.544 cm mold and pre-pressed under ambient conditions (0.4 N/cm.sup.2). Subsequently, the pre-pressed chip mat thus obtained was removed from the mold. For monitoring a temperature sensor (GaAs chip) was introduced into the center of said pre-pressed chip mat. Nonwoven separators were then provided to the upper and lower side of the pre-pressed chip mat. The pre-pressed chip mat was inserted in a HLOP 170 press from Hoefer Presstechnik GmbH, whereby a birch plywood (thickness 6 mm) was placed between the nonwoven separator and the press plate on each side of the mat. The pre-pressed chip mat was then compacted to 16 mm thickness in the press within a period of 2 s, and then heated by applying a high-frequency electrical field (27.12 MHz, anode current 2.7 A) while the press was remaining closed. When the target temperature 130 C. or 150 C. (HF temperature) was reached in the center of the pressed mat, the press was opened.

TABLE-US-00004 TABLE 3 3-layered chipboards, 16 mm, binder in core layer: Polylysine-2/glucose/fructose 75:12.5:12.5, binder amount in core layer 6 wt.-% (solid/dry wood), surface layers as given, binder amount in surface layers 6 wt.-% (solid/dry wood), pressed in high-frequency press internal binder in surface layers HF bond amine carbohydrate carbohydrate temperature density strength example component component 1 component 2 [ C.] [kg/m.sup.3] [N/mm.sup.2] 4-1 75% 12.5% 12.5% 130 659 0.89 Polylysine-2 Glucose Fructose 150 666 0.92 4-2 60% 20% 20% 130 651 0.85 Polylysine-2 Glucose Fructose 150 657 0.89 4-3 75% 12.5% 12.5% 130 669 0.91 Polylysine-3 Glucose Fructose 4-4 75% 25.0% 130 690 0.88 Polylysine-2 Xylose

Example 5

[0455] Three-Layered 16 mm Chipboards with Additional Urea

Preparation of Resinated Core Layer Chips (for Examples 5-1 to 5-8)

[0456] In a mixer, a mixture of 748 g of Kaurit glue 350 (65% solid content) and 22.4 g of ammonium sulfate was sprayed onto 5.58 kg (5.40 kg dry weight) of spruce core layer chips (moisture content 3.4%) while mixing. Subsequently, 95.0 g of water was sprayed onto the mixture to adjust the final moisture of the resinated chips while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 5-1)

[0457] In a mixer, a mixture of 486 g of Polylysine-2 solution (50 wt.-% in water), 81.0 g of fructose and 81.0 g of water was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 5-2)

[0458] In a mixer, a mixture of 486 g of Polylysine-2 solution (50 wt.-% in water), 162 g of urea, 81.0 g of fructose and 81.0 g of water was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 5-3)

[0459] In a mixer, a mixture of 486 g of Polylysine-2 solution (50 wt.-% in water), 81 g of urea, 81.0 g of fructose and 81.0 g of water was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 5-4)

[0460] In a mixer, a mixture of 564 g of Polylysine-2 solution (50 wt.-% in water), 162 g of urea, 42.1 g of fructose and 42.1 g of water was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 5-5)

[0461] In a mixer, a mixture of 564 g of Polylysine-2 solution (50 wt.-% in water), 81 g of urea, 42.1 g of fructose and 42.1 g of water was sprayed onto 5.67 g (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 5-6)

[0462] In a mixer, a mixture of 356 g of Polylysine-2 solution (50 wt.-% in water), 162 g of urea, 146 g of a fructose and 146 g of water was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Example 5-7)

[0463] In a mixer, a mixture of 356 g of Polylysine-2 solution (50 wt.-% in water), 81 g of urea, 146 g of fructose and 146 g of water was sprayed onto 5.67 g (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Thereafter, mixing was continued for 3 min.

Preparation of the Resinated Surface Layer Chips (Comparative Example 5-8*)

[0464] In a mixer, a mixture of 748 g of Kaurit glue 350 (65% solid content), 14.6 g of ammonium sulfate and 80.0 g of water was sprayed onto 5.67 kg (5.40 kg dry weight) of spruce surface layer chips (moisture content 5.0%) while mixing. Thereafter, mixing was continued for 3 min.

Pressing the Resinated Chips to Chipboards (Examples 5-1 to 5-8*)

[0465] Immediately after resignation, 452 g of resinated surface layer chips, followed by 1807 g of resinated core layer chips, followed by 452 g of resinated surface layer chips, were scattered into a 56.544 cm mold and pre-pressed under ambient conditions (0.4 N/cm.sup.2). Subsequently, the pre-pressed chip mat thus obtained was removed from the mold, transferred into a hot press and pressed to a thickness of 16 mm to give a chipboard (temperature of the press plates 210 C., max pressure 4 N/mm.sup.2, 96 s or 128 s corresponding to a press time factor of 6 s/mm or 8 s/mm (board thickness was adjusted by two steel spacing strips which were inserted in the press).

TABLE-US-00005 TABLE 4 3-layered chipboards, 16 mm, binder in core layer: Kaurit glue 350 9 wt.-% (solid/dry wood), binder in surface layer as given, binder amount in surface layer (components A1 + B1): 6 wt.-%, Polymer(s) press A1 or Weight Weight time Internal Formaldehyde comparative ratio ratio factor Density bond emission Example component A2 B1 A1:B1 A2:(A1 + B1) [s/mm] [kg/m.sup.3] [N/mm.sup.2] [mg/m.sup.2h] 5-1 Polylysine-2 Fru 75:25 6 665 0.81 1.8 8 674 0.82 1.8 5-2 Polylysine-2 Urea Fru 75:25 50:100.sup.1) 6 665 0.87 1.5 8 669 0.92 1.4 5-3 Polylysine-2 Urea Fru 75:25 25:100.sup.2) 6 665 0.87 1.5 8 670 0.88 1.4 5-4 Polylysine-2 Urea Fru 87:13 50:100.sup.3) 6 664 0.82 1.2 8 665 0.83 1.0 5-5 Polylysine-2 Urea Fru 87:13 25:100.sup.4) 6 663 0.80 1.2 8 671 0.83 1.1 5-6 Polylysine-2 Urea Fru 55:45 50:100.sup.5) 6 669 0.73 1.5 8 660 0.74 1.2 5-7 Polylysine-2 Urea Fru 55:45 25:100.sup.6) 6 665 0.70 1.6 8 662 0.72 1.3 5-8* UF resin (Kaurit glue 350) 8 678 0.85 2.9 9.0 wt.-% (solid/dry wood) *Comparative Examples .sup.1) weight ratio of Urea to Polylysine-2 = 40:60 .sup.2) weight ratio of Urea to Polylysine-2 = 25:75 .sup.3) weight ratio of Urea to Polylysine-2 = 36:64 .sup.4) weight ratio of Urea to Polylysine-2 = 22:78 .sup.5) weight ratio of Urea to Polylysine-2 = 48:52 .sup.6) weight ratio of Urea to Polylysine-2 = 31:69 The addition of urea as component A2 further reduces formaldehyde emission.