Product Introduction
Boric acid is a monobasic acid that exhibits extremely weak acidity (Ka = 5.8 × 10⁻¹⁰), similar to silicic acid (K₁ = 2 × 10⁻¹⁰). Upon ionisation in water, it does not donate protons directly but instead forms a complex with hydroxide ions present in the solution:
H3BO3 + 2H2O-- H3O^+ + B(OH)_4^-
This behaviour is related to the electron-deficient nature characteristic of boron compounds. In boric acid, the boron atom acts as an electron pair acceptor by bonding with a hydroxide ion, where the oxygen atom serves as the electron pair donor. Thus, boric acid is considered a typical Lewis acid.
When glycerol or mannitol [CH₂(OH)(CHOH)₄CH₂OH] is added to a boric acid solution, its acidity increases. This is because boric acid forms a coordination complex (anion) with glycerol, which facilitates the release of H⁺ ions, thereby enhancing ionisation.
Boric acid appears as fine white crystalline powder, with CAS number 10043-35-3 and molecular formula H₃BO₃. Our supplied boric acid reaches 99.8% purity, available in reagent grade and photographic grade specifications, stable chemical property and low impurity content to meet strict industrial and laboratory standards.
Core Product Specifications
CAS Number: 10043-35-3
Chemical Formula: H₃BO₃
Purity: 99.8% min
Appearance: White fine crystalline powder
Synonyms: Reagent grade boric acid powder, photographic grade boric acid
MOQ: 1 FCL (Full Container Load)
Key Chemical Properties
Beyond its weak Lewis acid characteristics, boric acid features low volatility under normal temperature and pressure. It is slightly soluble in cold water and soluble in hot water, ethanol and glycerin. When heated stepwise, it undergoes dehydration reaction: losing water at around 100℃ to generate metaboric acid, and further decomposing at high temperature to form tetraborate and boron trioxide.
It has good corrosion inhibition, flame retardant and antiseptic properties, and will not react violently with most neutral organic raw materials under regular operating conditions.
Main Application Scenarios
Photographic Industry
As a key pH buffer for photographic developing solutions, it stabilizes the pH value of developer liquid to guarantee consistent exposure and imaging quality of photographic films and papers.
Laboratory & Reagent Field
Used as analytical reagent, buffer solution preparation raw material. It is widely applied in titration experiments and inorganic chemistry research for studying weak acid coordination reaction.
| Boric acid Chemical Properties |
| Melting point | 160 °C (dec.) (lit.) |
| Boiling point | 219-220 °C (9.7513 mmHg) |
| bulk density | 400-600kg/m3 |
| density | 1.440 g/cm3 |
| vapor pressure | 2.6 mm Hg ( 20 °C) |
| refractive index | n20/D 1.330-1.340 |
| storage temp. | Store at +5°C to +30°C. |
| solubility | H2O: soluble |
| pka | 8.91±0.43(Predicted) |
| form | working solution |
| color | ≤10(APHA) |
| Specific Gravity | 1.435 |
| Odor | Odorless |
| PH | 3.6-4.4 (25℃, saturated solution in H2O) |
| PH Range | 3.8 - 4.8 |
| Water Solubility | 49.5 g/L (20 ºC) |
| λmax | λ: 260 nm Amax: 0.05 λ: 280 nm Amax: 0.05 |
| Sensitive | Hygroscopic |
| Merck | 14,1336 |
| BRN | 1697939 |
| Exposure limits | ACGIH: TWA 2 mg/m3; STEL 6 mg/m3 |
| Cosmetics Ingredients Functions | BUFFERING DENATURANT ANTIMICROBIAL |
| Cosmetic Ingredient Review (CIR) | Boric acid (10043-35-3) |
| InChI | 1S/BH3O3/c2-1(3)4/h2-4H |
| InChIKey | KGBXLFKZBHKPEV-UHFFFAOYSA-N |
| SMILES | OB(O)O |
| LogP | -1.09 at 22℃ |
| CAS DataBase Reference | 10043-35-3(CAS DataBase Reference) |
| NIST Chemistry Reference | B(OH)3(10043-35-3) |
| EPA Substance Registry System | Orthoboric acid (10043-35-3) |
| Absorption | ≤0.05 at 260 in H2O at 1M ≤0.05 at 280 in H2O at 1M |
| Safety Information |
| Hazard Codes | Xi,T,Xn |
| Risk Statements | 36/37/38-60-63-62-61 |
| Safety Statements | 26-36-53-45-37/39-36/37/39-22-24/25-23 |
| WGK Germany | 2 |
| RTECS | ED4550000 |
| F | 3 |
| TSCA | TSCA listed |
| HS Code | 28100090 |
| Storage Class | 6.1C - Combustible acute toxic Cat.3 toxic compounds or compounds which causing chronic effects |
| Hazard Classifications | Repr. 1B |
| Hazardous Substances Data | 10043-35-3(Hazardous Substances Data) |
| Toxicity | LD50 orally in rats: 5.14 g/kg (Smyth). |
Industrial Manufacturing
Glass & Ceramic: Used in borosilicate glass, enamel and ceramic glaze production, improving heat resistance, transparency and surface gloss of finished products.
Flame Retardant: Serves as additive for wood, textile and paper flame retardant treatment, suppressing combustion and smoke generation.
Metal Surface Treatment: Functions as corrosion inhibitor for steel and non-ferrous metal surface passivation and pickling auxiliary agent.
Other Uses
Can be applied in cosmetics raw material, agricultural trace element fertilizer and preservative formulation under corresponding regulatory restrictions.
Packaging & Transportation
Packaging Option: 25kg woven bag with inner PE plastic liner. Customized packaging labels with company logo and product marks are available upon customer request.
Shipping Method: Full container sea shipment (FCL). We arrange container loading, container inspection and palletizing service.
Transport Notes: Boric acid is non-explosive ordinary chemical goods. Keep away from strong alkali, strong oxidizers during storage and transit. Store in dry, cool and ventilated warehouse, avoid moisture absorption.
Document Supply: We can provide commercial invoice, packing list, CO, COA, MSDS and other customs clearance documents required for import declaration.
Our Quality Control System
We implement full-process quality inspection from raw material incoming check to finished product delivery. Each batch will be sampled and tested before shipment. The issued COA covers purity, moisture, heavy metal impurities and physical indicators. Third-party inspection such as CCIC can be accepted according to customer’s requirement. Any deviation against agreed specification will be handled before loading.
After-sales Service
Pre-shipment: Provide technical data sheet, MSDS and professional chemical consultation for formulation and usage guidance.
Shipment tracking: Offer bill of lading copy, container loading photos and real-time logistics update after vessel departure.
After arrival support: Respond to product quality inquiry within 24 working hours. If confirmed quality problem caused by our side, we will negotiate compensation solution based on contract terms.
Technical team support: Our chemist team can help solve technical questions about dissolution, pH adjustment and formula matching.
Customer Cases
We have long-term cooperation with photographic chemical factories, glass ceramic manufacturers and laboratory reagent distributors across Southeast Asia, Middle East and Latin America. Our 99.8% photographic grade boric acid has been stably supplied for multiple container orders, with stable quality and smooth customs clearance records. We support long-term framework contracts for regular bulk buyers.
FAQ
Q1: Can I order LCL less than one full container?
A: Our MOQ for this product is 1 FCL. At present we only accept full-container orders to control unit cost and avoid product moisture risk during LCL transit.
Q2: What documents can you provide for customs clearance?
A: We can supply Commercial Invoice, Packing List, Certificate of Origin, COA, MSDS. Extra certification can be discussed according to your destination country import requirement.
Q3: Is this boric acid photographic grade?
A: Yes. We supply photographic grade boric acid powder with 99.8% purity, suitable for photo developing liquid formulation, and also provide reagent grade option.
Q4: What is the storage life of boric acid?
A: Under dry and sealed storage condition, the shelf life is 24 months. Keep packages sealed to prevent absorbing moisture from air.
Q5: What is the payment term available?
A: We support multiple payment terms such as T/T. Payment terms can be further negotiated for long-term bulk cooperation.
Why Choose Us
We are professional chemical raw material supplier with rich export experience. We strictly control batch stability, provide complete customs documents and one-stop logistics coordination service. Our team is familiar with international chemical import regulations of different countries, helping you reduce clearance risks. We maintain transparent communication throughout order production, loading and sea freight.
