Sikafloor® -25N PurCem (CN) Medium Duty, Electrostatic Dissipative, Self-Levelling
发布时间：2023/05/15
Product Data Sheet
Edition 20/03/2012EN
Sikafloor® -25N PurCem (CN)
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Sikafloor® -25N PurCem (CN)
Sikafloor® -25N PurCem (CN)
Medium Duty, Electrostatic Dissipative, Self-Levelling
Polyurethane Screed
Product
Description
Sikafloor® -25N PurCem (CN) is self-levelling, medium duty, electrostatic dissipative,
solid colour, five-component, water dispersed polyurethane-based / cement and
aggregate screed designed to provide good resistance to abrasion, impact,
chemical attack and other physical aggression. Sikafloor ® 25N Purcem (CN) has
an aesthetic, easy to clean, smooth aggregate texture. The systems are typically
installed at 4 to 5 mm thickness.
Uses
Typically used in food processing plants, wet & dry process areas, freezers &
coolers, dairies, breweries, wineries, distilleries, laboratories, chemical process
plants, pulp and paper plants, warehouses and storage areas.
Characteristics /
Advantages
Resists a very wide range of organic and inorganic acids, alkalis, amines, salts
and solvents. Consult Sika Technical Sales for full details. Refer to the Sikafloor®
PurCem (CN) Chemical Resistance Chart.
Electrostatic Dissipative Properties
Similar coefficient of thermal expansion to concrete allowing movement with the
substrate through normal thermal cycling. It will perform and retain its physical
characteristics through a wide temperature range from -5ºC up to 65ºC.
Bond strength in excess of the tensile strength of concrete, concrete will fail first.
High abrasion qualities result from its pure silica aggregate structure.
Extra Expansion joints are not necessary; simply maintain and extend existing
expansion joints up through the Sikafloor® PurCem (CN) Flooring System.
Easily maintained.
Technical Data
Packaging
33.42 kg set.
Colour
Seven standard colours are available (all are approximate):
Beige, Maize Yellow, Oxide Red, Grass Green, Slate Grey, Dusty Grey, Traffic
Grey
Custom colours subject to minimum orders.
Yield
Approximately 4.32 m2 per unit at 4 mm
(These figures do not allow for surface porosity, profile or wastage)
Shelf Life
Components A+B: 1year in original unopened packaging.
Component C/D/E : 6 months in original unopened packaging.
Store dry between 10 ºC - 25 ºC. Protect from freezing.
Mix Ratio
Mix full units only.
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Sikafloor® -25N PurCem (CN)
Properties at 23°C and
50% R.H.
Density ASTM C 905
1.93 kg/L
Flow ASTM C230
320 mm
Service Temperature
-5ºC min. / 65ºC max.
The product is not designed to withstand thermal shock. Hot steam cleaning is not
recommended
Cure Time at
Usable pot life 15-20 min at 20ºC
Initial join up time 20-25 min at 20ºC / 4 mm
Cure to foot traffic 10-12 h at 20ºC / 4 mm
Cure to light traffic 14-16 h at 20ºC / 4 mm
Full cure 5 days at 20ºC / 4 mm
Compressive Strength
ASTM C579
24 h 27 MPa
7 days 37 MPa
28 days 40 MPa
Tensile Strength ASTM C
307
6.5 MPa
Flexural Strength ASTM
C 580
14.7 MPa
Bond Strength ASTM D
4541
> 1.75 MPa (substrate failure)
Hardness, Shore D
ASTM D 2240
80-85
Electrical Resistance
IEC 61340-4-1
Resistance To Earth / Surface to Surface < 109 Ω
Abrasion Resistance
ASTM D 4060
H-22/1000 cycles/1000 g
-2.26 g
Chemical Resistance
Consult Sika Technical Department
How to Use
Surface Quality and
Preparation
The concrete substrate must be sound and of sufficient compressive strength
(minimum 25 N/mm2 ) with a minimum pull off strength of 1.5 N/mm2 .
The substrate must be clean and dry, and free of all contaminants such as oil,
grease, coatings and surface treatments, etc.
Remove all dust, dirt, existing paint films, efflorescence, exudates, laitance, form
oils, hydraulic or fuel oils, brake fluid, grease, fungus, mildew, biological residues or
any other contaminants which may prohibit good bond. Prepare the surface by
appropriate mechanical means, approved by Sika to achieve (CSP 3-9). Repairs to
cementitious substrates, filling of blowholes, leveling of irregularities, etc. should be
carried out using an appropriate Sika profiling mortar.
Contact Sika Technical Sales for a recommendation.
Edge Terminations - All free edges of a Sikafloor® PurCem (CN), whether at the
perimeter, along gutters or at drains require extra anchorage to distribute
mechanical and thermal stresses. This is best achieved by forming or cutting
grooves in the concrete. Grooves should have a depth and width of 2 times
thickness of the Sikafloor® PurCem (CN) mortar. Refer to the edge details provided.
If necessary, protect all free edges with mechanically attached metal strips.
Never featheredge, always turn into an anchor groove.
Expansion Joints - Should be provided in the substrates at the intersection of
dissimilar materials. Isolate areas subject to thermal stresses, vibration movements
or around load-bearing columns and at vessel sealing rings. Refer to details. 3
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Sikafloor® -25N PurCem (CN)
Mixing of Sikafloor25N
Purcem (CN)
Mixing will be affected by temperature; condition materials for use from 18ºC to
25ºC. Premix components A separately, make sure all pigment is uniformly
distributed.
Start mixer; stir for 10 seconds component A, then add component B and mix for 30
seconds. Add component C (powder) and component D (pigment powder)
together, pouring slowly over a period of 15 seconds. DON’T DUMP!
Allow component C and D to further mix for 2 more minutes to ensure complete
mixing. Add Component E and mix for 1 minutes at low speed 300~400RPM.
During the operations, scrape down the sides and bottom of the container with a flat
or straight edge trowel at least once (Components A+B+C+D+E) to ensure
complete mixing. Mix full units only.
Note: Improve flowability on cool substrates can be achieved by removing a
maximum of 1 kg of Component C (powder) per unit.
Application Placing of earthing points:
See below “Notes on Application / Limits”.
Sikafloor® -25N PurCem (CN)
Priming – Apply a scratch coat of Sikafloor® -25N Purcem (CN), at application rate
of approx. 1.5 kg/m².
Sikafloor 25N Purcem (CN) - Mix and pour the Sikafloor®-25N PurCem (CN)
materials on the cured scratch coat. Spread to the desired thickness using a
notched trowel. Take care to spread newly mixed materials across the transition of
previous applied mixes before the surface begins to set. Immediately spiked roll the
surface to release trapped air in the matrix.
Respect curing times, prior to open Sikafloor 25N Purcem (CN) to traffic.
Clean Up
Clean all tools and equipment with Sika® Equipment Cleaner/Epoxy Thinner. Wash
soiled hands and skin thoroughly in hot soapy water or use Sika® Hand Cleaner.
Once hardened, product can only be removed mechanically.
Maintenance
Sikafloor® PurCem (CN) floors are easily cleaned using a stiff brushing action and
or high-pressure water, preferably hot, and even live steam. Degreasing agents and
detergents will assist, but do not use any compounds containing Phenol as the floor
colour may be damaged. Consult the cleaning compound manufacturer’s printing
directions before use.
Note on Application/
Limitations
■ Do not apply below 10ºC or above 30ºC / maximum relative humidity 85%.
■ Do not apply to un-reinforced sand cement screeds, asphaltic or bitumen
substrate, glazed tile or non-porous brick, tile and magnesite, copper, aluminium,
soft wood, or urethane composition, elastomeric membranes, fibre reinforced
polyester (FRP) composites.
■ Do not apply to wet or green concrete or polymer modified patches if the
moisture content > 10%.
■ Do not apply to concrete if air or substrate temperature is within 3ºC of dew
point.
■ Protect substrate during application from condensation from pipes or any
overhead leaks.
■ Do not apply to vertical or overhead surfaces / for vertical surfaces refer to
Sikafloor® 29N PurCem (CN).
■ Do not featheredge.
■ Do not mix Sikafloor® PurCem materials by hand / mechanical mix only.
■ Do not apply to cracked or unsound substrates.
■ Do not apply to surfaces where moisture vapour can condense and freeze.
■ Steam cleaning may lead to delamination due to thermal shock (Please consult
our technical department for further advice on our solution)
■ Colour uniformity cannot be completely guaranteed from batch to batch
(numbered). Take care when using Sikafloor® PurCem products to draw from
inventory in batch number sequence, do not mix batch numbers in a single floor
area.
■ Always allow a minimum of 48 hours after product application prior to placing
into service in proximity with food stuffs. 4
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■ Products of the Sikafloor® - PurCem® (CN) product range are subject to yellowing
when exposed to UV radiation. There are no measurable losses of other properties
when this occurs and it is a purely aesthetical matter. Products can be used outside
provided the change in appearance is acceptable by the customer.
■ Before the application of an anti-static flooring system, a reference area has to
be applied. This reference area must be assessed and accepted from the
contractor/client. The desired result and method of conductivity measurement must
be stated in the Specification and Method Statement. The number of conductivity
measurements is strongly recommended to be as shown in the table below:
Applied floor area Number of measurements
< 10 m² 1 measurement / m²
10-100 m² 10 - 20 measurements
> 100 m² 10 measurements / 100m²
The measuring points must have a distance of at least 50 cm to the next
measuring point. In case of a measurement lower/higher than required, an
additional measurement has to be carried out within 50 cm of the point with the
insufficient result.
Placing of earthing points:
If the Sikafloor® Earthing Kit conductor system (system of anchored brass-plates
with stable earth connection) is applied, the instructions for use have to be followed
exactly. Every earthing point is able to conduct approx. 300 m². Ensure the longest
distance of each point in the area is max. 10 m to the next earthing point. Clean the
earthing spots carefully. For longer distances, additional earthing points have to be
placed. If site conditions do not allow placing of additional earthing points, longer
distances (>10 m) have to be bridged with copper tapes. The earthing spots have to
be connected to the ring-mains. This work must be executed and approved by an
electrical engineer and in accordance with any relevant regulations
Numbers of earth connections:
Per room al least 2 earthing points. The optimum number of earth connections
depends on the local conditions and should be specified with documents.
The incorrect assessment and treatment of cracks may lead to a reduced service
life and reflective cracking - reducing or breaking conductivity.
Caution Component A - Frequent or prolonged skin contact may cause some local short
term skin irritation. Avoid eyes contact, may cause slight transient irritation.
Component B - Harmful by inhalation. Irritating to eyes, respiratory system and
skin. May cause sensitization by inhalation and skin contact.
Component C and D- Risk of serious damage to eyes. In case of contact with
eyes, rinse immediately with plenty of water. May cause skin irritation. Avoid
breathing dusts. Respirable dusts could if inhaled over a prolonged period
constitute a health hazard.
Component E- Irritation accompanied by itching or dermatitis may occur from
exposure to broken filaments or loose particle of the fibres.
Consult product label for additional information.
First Aid
In case of skin contact, wash thoroughly with soap and water. For eye contact, flush
immediately with plenty of water for at least 15 minutes. Contact a physician
immediately. For respiratory problems, transport victim to fresh air.
For more information, consult Sika Material Safety Data Sheet.
Value Base
All technical data stated in this Product Data Sheet are based on laboratory tests.
Actual measured data may vary due to circumstances beyond our control.
Local Restrictions Please note that as a result of specific local regulations the performance of this
product may vary from country to country. Please consult the local Product Data
Sheet for the exact description of the application fields.
Health and Safety
Information
For information and advice on the safe handling, storage and disposal of chemical
products, users shall refer to the most recent Material Safety Data Sheet containing
physical, ecological, toxicological and other safety-related data.
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Notes:
The information, and, in particular, the recommendations relating to the application and end-use of Sika products, are given in
good faith based on Sika's current knowledge and experience of the products when properly stored, handled and applied
under normal conditions in accordance with Sika’s recommendations. In practice, the differences in materials, substrates and
actual site conditions are such that no warranty in respect of merchantability or of fitness for a particular purpose, nor any
liability arising out of any legal relationship whatsoever, can be inferred either from this information, or from any written
recommendations, or from any other advice offered. The user of the product must test the product’s suitability for the intended
application and purpose. Sika reserves the right to change the properties of its products. The proprietary rights of third parties
must be observed. All orders are accepted subject to our current terms of sale and delivery. Users must always refer to the
most recent issue of the local Product Data Sheet for the product concerned, copies of which will be supplied on request.
Sika (China) Ltd.
No.28 Jingdong Road, Suzhou Industrial Park,
JiangSu,P.R.China
Postal Code: 215121
ISO 9001: 2008 ISO 14001:2004
Certificate No.:CC3576 Certificate No.:CC3577
The product is manufactured under a HKQAA
ISO9001/ISO14001
certified quality/environmental management system.
Construction